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Sample records for rat forced swimming

  1. B-type natriuretic peptide (BNP serum levels in rats after forced repeated swimming stress

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    Almira Hadžovic-Džuvo

    2011-02-01

    Full Text Available Aim To estimate the effects of forced repeated swimming stress on BNP serum levels in rats. Methods Adult male Wistar rats weighting between 280-330 g were divided into two groups: control group (n =8 and stress group (n =8. Rats in the stress group were exposed to forced swimming stress daily, for 7 days. The rats were forced to swim in plastic tanks (90 cm wide, 120 cm deep containing tap water (temperature ca. 25°C. The depth of water was 40 cm. Duration of each swimming session progressively increased from 10 minutes on the irst day to 40 minutes on days 6 and 7. Rats were sacriiced and blood was drawn from abdominal aorta for BNP analysis immediately after the last swimming session. B-type natriuretic serum level was determined by ELISA method using RAT BNP-32 kit (Phoenix Pharmaceutical Inc.. Results There was no statistically signiicant difference between mean BNP serum level in the stress group after the swimming period (0.81±0.14 ng/ml as compared to the unstressed group of rats (0.8 ±0.08ng/ml. After the swimming period mean body weight slightly decreased in the stress group in comparison with values before stress period (296.3 g vs.272.8 g, but this difference was not statistically signiicant. The stress period had no inluence on food intake in the stress rat group. Conclusion The workload consisting of 40-minutes long swimming session is not suficient to provoke BNP release from myocardium in rats.

  2. B-type natriuretic peptide (BNP) serum levels in rats after forced repeated swimming stress.

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    Hadzovic-Dzuvo, Almira; Valjevac, Amina; Avdagić, Nesina; Lepara, Orhan; Zaćiragić, Asija; Jadrić, Radivoj; Alajbegović, Jasmin; Prnjavorac, Besim

    2011-02-01

    To estimate the effects of forced repeated swimming stress on BNP serum levels in rats. Adult male Wistar rats weighting between 280-330 g were divided into two groups: control group (n = 8) and stress group (n = 8). Rats in the stress group were exposed to forced swimming stress daily, for 7 days. The rats were forced to swim in plastic tanks (90 cm wide, 120 cm deep) containing tap water (temperature ca. 25 degrees C). The depth of water was 40 cm. Duration of each swimming session progressively increased from 10 minutes on the first day to 40 minutes on days 6 and 7. Rats were sacrificed and blood was drawn from abdominal aorta for BNP analysis immediately after the last swimming session. B-type natriuretic serum level was determined by ELISA method using RAT BNP-32 kit (Phoenix Pharmaceutical Inc.). There was no statistically significant difference between mean BNP serum level in the stress group after the swimming period (0.81 +/- 0.14 ng/ml) as compared to the unstressed group of rats (0.8 +/- 0.08 ng/ml). After the swimming period mean body weight slightly decreased in the stress group in comparison with values before stress period (296.3 g vs. 272.8 g), but this difference was not statistically significant. The stress period had no influence on food intake in the stress rat group. The workload consisting of 40-minutes long swimming session is not sufficient to provoke BNP release from myocardium in rats.

  3. Effect of forced swim stress on wistar albino rats in various behavioral parameters

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    Ambareesha Kondam, Nilesh N Kate, Gaja Lakshmi, Suresh M, Chandrashekar M.

    2012-09-01

    Full Text Available Introduction: Stress is an important factor of depression that causes the changes in various body systems. The forced swim test is a commonly used stressor test where rats are forced to swim in specially constructed tanks for a particular period where there is behavioral activation characterized by vigorous swimming and diving to search for alternate routes of escape. Animal health including human has been shown to be affected by the stressful events of life inducing situation which alters cognition, learning memory and emotional responses, causing mental disorders like depression and anxiety and stress in rats. Methods: The experiment was carried out with 12 healthy albino Wistar female rats weighing about 150-180gms. The animals were randomly divided into two groups of six animals each. Group – I (control, Group – II (Stressed Group. Group –II rats are placed in plastic tanks for 45minutes for15 days. Temperature of water was maintained at 20˚C. During stress phase, the animals will be trained for forced swim test, behavioral changes observed by open field apparatus for emotions, and eight arm maze for memory & leaning, elevated plus maze for anxiety. Results: Forced swim stress causes to a significant change (p<0.05 on cognitive functions: motivation, learning and memory. Forced swim stress is the factor damaging the hippocampus causes repeated immobilization and produce atrophy of dendrites of pyramidal neurons and neuroendocrinological disturbances, controlled by the hypothalamo-pituitary-adrenal axis (HPA. Repeated stress in the form of forced swimming activates the free radical processes leading to an increase in lipid peroxidation in many tissues. Conclusion: This study reveals the effect of repeated forced swim stress causes wide range of adaptive changes in the central nervous system including the elevation of serotonin (5-HT metabolism and an increased susceptibility to affective disorders. The earlier findings have reported

  4. Forced swimming stress does not affect monoamine levels and neurodegeneration in rats.

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    Abbas, Ghulam; Naqvi, Sabira; Mehmood, Shahab; Kabir, Nurul; Dar, Ahsana

    2011-10-01

    The current study was aimed to investigate the correlations between immobility time in the forced swimming test (FST, a behavioral indicator of stress level) and hippocampal monoamine levels (markers of depression), plasma adrenalin level (a peripheral marker of stress) as well as fluoro-jade C staining (a marker of neurodegeneration). Male Sprague-Dawley rats were subjected to acute, sub-chronic (7 d) or chronic (14 d) FSTs and immobility time was recorded. Levels of noradrenalin, serotonin and dopamine in the hippocampus, and adrenalin level in the plasma were quantified by high-performance liquid chromatography with electrochemical detection. Brain sections from rats after chronic forced swimming or rotenone treatment (3 mg/kg subcutaneously for 4 d) were stained with fluoro-jade C. The rats subjected to swimming stress (acute, sub-chronic and chronic) showed long immobility times [(214 +/- 5), (220 +/- 4) and (231 +/- 7) s, respectively], indicating that the animals were under stress. However, the rats did not exhibit significant declines in hippocampal monoamine levels, and the plasma adrenalin level was not significantly increased compared to that in unstressed rats. The rats that underwent chronic swimming stress did not manifest fluoro-jade C staining in brain sections, while degenerating neurons were evident after rotenone treatment. The immobility time in the FST does not correlate with markers of depression (monoamine levels) and internal stress (adrenalin levels and neurodegeneration), hence this parameter may not be a true indicator of stress level.

  5. Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test

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    Ciulla,Leandro; Menezes,Honório Sampaio; Bueno,Bárbara Beatriz Moreira; Schuh,Alexandre; Alves,Rafael José Vargas; Abegg,Milena Pacheco

    2007-01-01

    PURPOSE: To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. METHODS: Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST). Immobility and number of stops were measured. RESULTS: Rats given injections of fluoxetine displayed significantly less immobility (p = 0.02) and fewer stops than the control group (p = 0.003). Duloxetine significanlty reduced the nu...

  6. Effect of Eight Weeks Forced Swimming Training with Methadone Supplementation on Aspartate Aminotransferase, Alanine Aminotransferase, and Alkaline Phosphatase of Rats

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    Seyed Ali Hoseini

    2016-12-01

    Full Text Available Background & Objective: Narcotics abuse can induce liver disorders; nevertheless, exercises improve liver disorders. The present research aimed to review the effect of eight weeks forced swimming training with methadone supplementation on liver enzymes of rats. Material & Method: In this experimental research, 48 rats were selected, and after one week adaptation to lab environment, they were randomly divided into four groups of 12 rats including (1 forced swimming training, (2 methadone supplementation, (3 forced swimming training with methadone supplementation, and (4 control. Groups 2 and 3 used 2 mg/kg methadone daily for 8 weeks. Also, groups 1 and 3 swam for 8 weeks, three sessions per week and each session for 30 minutes. For statistical analysis of data, one way ANOVA and Tukey post hoc tests were used (α≤0.05. Results: Findings showed that forced swimming training, methadone supplementation, and forced swimming training with methadone supplementation had no significant effect on AST (P=0.90 and ALT (P=0.99 enzymes; forced swimming training had significant effect on increase of ALP (P=0.001; also, forced swimming training, compared with methadone supplementation and combination of forced swimming training with methadone supplementation, had significant effect on increase of ALP (P=0.001. Conclusion: Accordingly, 8 weeks of forced swimming training with methadone has possibly no significant effect on liver enzymes.

  7. Omega-3 fatty acids have antidepressant activity in forced swimming test in Wistar rats.

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    Lakhwani, Lalit; Tongia, Sudheer K; Pal, Veerendra S; Agrawal, Rajendra P; Nyati, Prem; Phadnis, Pradeep

    2007-01-01

    Forced swimming test is used to induce a characteristic behavior of immobility in rats, which resembles depression in humans to some extent. We evaluated the effect of omega-3 fatty acids alone as well as compared it with the standard antidepressant therapy with fluoxetine in both acute and chronic studies. In both the studies, rats were divided into 4 groups and subjected to the following drug interventions - Group 1- control: Group 2- fluoxetine in dose of 10 mg/kg subcutaneously 23.5, 5 and 1 h before the test: Group 3- omega-3 fatty acids in dose of 500 mg/kg orally; Group 4- fluoxetine plus omega-3 fatty acids both. In acute study, omega-3 fatty acids were given in single dose 2 h prior to the test while in chronic study omega-3 fatty acids were given daily for a period of 28 days. All animals were subjected to a 15-min pretest followed 24 h later by a 5-min test. A time sampling method was used to score the behavioral activity in each group. The results revealed that in acute study, omega-3 fatty acids do not have any significant effect in forced swimming test. However, in chronic study, omega-3 fatty acids affect the immobility and swimming behavior significantly when compared with control (p fluoxetine is significantly more than that of fluoxetine alone in changing the behavioral activity of rats in forced swimming test. It leads to the conclusion that omega-3 fatty acids have antidepressant activity per se, and the combination of fluoxetine and omega-3 fatty acids has more antidepressant efficacy than fluoxetine alone in forced swimming test in Wistar rats.

  8. Serotonergic mediation of the effects of fluoxetine, but not desipramine, in the rat forced swimming test.

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    Page, M E; Detke, M J; Dalvi, A; Kirby, L G; Lucki, I

    1999-11-01

    The forced swimming test (FST) is a behavioral test in rodents that predicts the clinical efficacy of many types of antidepressant treatments. Recently, a behavior sampling technique was developed that scores individual response categories, including swimming, climbing and immobility. Although all antidepressant drugs reduce immobility in the FST, at least two distinct active behavioral patterns are produced by pharmacologically selective antidepressant drugs. Serotonin-selective reuptake inhibitors increase swimming behavior, while drugs acting primarily to increase extracellular levels of norepinephrine or dopamine increase climbing behavior. Distinct patterns of active behaviors in the FST may be mediated by distinct neurotransmitters, but this has not been shown directly. The present study examined the role of serotonin in mediating active behaviors in the forced swimming test after treatment with two antidepressant drugs, the selective serotonin reuptake inhibitor, fluoxetine and the selective norepinephrine reuptake inhibitor, desipramine. Endogenous serotonin was depleted by administering para-cholorophenylalanine (PCPA, 150 mg/kg, IP.) to rats 72 h and 48 h prior to the swim test. Fluoxetine (10 mg/kg, SC) or desipramine (10 mg/kg, SC) was given three times over a 24-h period prior to the FST. Behavioral responses, including immobility, swimming and climbing, were counted during the 5-min test. Pretreatment with PCPA blocked fluoxetine-induced reduction in immobility and increase in swimming behavior during the FST. In contrast, PCPA pretreatment did not interfere with the ability of desipramine to reduce immobility and increase climbing behavior. Depletion of serotonin prevented the behavioral effects of the selective serotonin reuptake inhibitor fluoxetine in the rat FST. Furthermore, depletion of serotonin had no impact on the behavioral effects induced by the selective norepinephrine reuptake inhibitor, desipramine. The effects of antidepressant drugs

  9. Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test.

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    Ciulla, Leandro; Menezes, Honório Sampaio; Bueno, Bárbara Beatriz Moreira; Schuh, Alexandre; Alves, Rafael José Vargas; Abegg, Milena Pacheco

    2007-01-01

    To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST). Immobility and number of stops were measured. Rats given injections of fluoxetine displayed significantly less immobility (p = 0.02) and fewer stops than the control group (p = 0.003). Duloxetine significantly reduced the number of stops (p = 0.003), but did not effect immobility (p = 0.48). Duloxetine and fluoxetine reduced depressive behaviors in the Forced FST. However, our findings suggest that fluoxetine is more effective than duloxetine.

  10. [A comparative study on behaviors of two depression models in rats induced by chronic forced swimming stress].

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    Han, Ming-Fei; Gao, Dong; Sun, Xue-Li

    2010-01-01

    To compare the behaviors of rats with depressions induced by chronic forced swimming stress under two different conditions. Eighteen male rats were randomly divided into 3 groups, with 6 rats in each group. The rats in the control group (C group) were not forced into swimming, while the rats in the stress groups (S1 and S2) were forced to swim for 14 consecutive days. The rats in S1 group and S2 group swam for five minutes every morning, in water with (23 +/- 1) degree C, and (10 +/- 0.5) degree C in temperature, respectively. The weight gain, food intake, open-field test and saccharin solution test were observed on the seventh day and fourteenth day. On the seventh day following chronic swim stress, the rats in the S2 group had significant lower ratio in weight gain and food intake than the controls (P forced swimming. On the fourteenth day, the rats in the S1 group still had lower ratio in weight gain, but had higher ratio in food intake and preference for saccharin solution, and greater number of crossing than the controls. Chronic forced swimming at a lower temperature could induce depression better than at a higher temperature.

  11. Sex-dependent effects of fluoxetine and triiodothyronine in the forced swim test in rats.

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    Lifschytz, Tzuri; Shalom, Galit; Lerer, Bernard; Newman, Michael E

    2006-02-01

    The effects of triiodothyronine (T3) and fluoxetine, administered separately and combined, on behavior of male and female rats in the forced swim test, a procedure for screening antidepressant-like activity, were determined. There were no consistent effects of low doses of fluoxetine (5 mg/kg) or T3 (20 microg/kg), administered daily for 2 weeks. Fluoxetine administered daily at 10 mg/kg for 7 days reduced immobility and increased active behaviors in male rats, but had no effects in female rats. The effects of fluoxetine in male rats were not potentiated by T3. In female rats, T3 at 100 microg/kg given daily for 7 days decreased immobility and increased swimming when these were measured 72 h after the last injection, but not when measurements were performed at an earlier time point. These results provide some support from an animal model for the efficacy of T3 as antidepressant therapy in female patients, but do not provide support for the augmentation and acceleration effects seen clinically when T3 is used in conjunction with established antidepressants such as fluoxetine.

  12. Postnatal cocaine exposure: effects on behavior of rats in forced swim test.

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    Magalhães, Ana; Tavares, Maria Amélia; de Sousa, Liliana

    2002-06-01

    Exposure to cocaine in early periods of postnatal life has adverse effects on behavior, namely, it induces the display of anxiety and fear-like behaviors that are associated with stress and depression. This study examined the effects of early developmental cocaine exposure in several categories of behavior observed in forced swim test. Male and female Wistar rats were given 15 mg/kg of cocaine hydrochloride/body weight/day, subcutaneously, in two daily doses, from postnatal day (PND) 1 to PND27. Controls were saline injected in the same protocol. In PND26-PND27, rats were placed in a swimming pool during 5 min in two sessions. The categories of behavior studied in this work included horizontal and vertical rotation, vibrissae clean, head clean, fast and slow swim, struggling, floating, sliding, diving, head-diving, and wagging head. Results showed differences in the frequencies of several behavioral categories that allowed the discrimination of the behaviors that may constitute "behavioral despair" indicators, as well as which behaviors are most affected by cocaine exposure. Cocaine groups were less active and more immobile than controls. These results suggest that postnatal exposure to cocaine can produce depression-like effects and affect the ability of these animals to cope with stress situations.

  13. Impact of melatonin supplementation in the rat spermatogenesis subjected to forced swimming exercise.

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    Moayeri, A; Mokhtari, T; Hedayatpour, A; Abbaszadeh, H-A; Mohammadpour, S; Ramezanikhah, H; Shokri, S

    2018-04-01

    Oxygen consumption increases many times during exercise, which can increase reactive oxygen species. It negatively affects fertility in male athletes. Melatonin is exerting a regulatory role at different levels of the hypothalamic-pituitary-gonadal axis. However, there is no evidence that the protective effects of melatonin persist after long duration exercise on the spermatogenesis. Therefore, this study was conducted to examine the impacts of melatonin on the testis following the administration of swimming exercise. Rats were separated into five different groups, including Control, sham M: received the solvent of melatonin, M: received melatonin, S: the exercise protocol, MS: received melatonin and the exercise protocol. After 8 weeks, animals were scarified and antioxidant enzymes levels of testes, spermatogenic cells apoptosis and sperm quality were measured. Swimming decreased all parameters of spermatozoa. Nevertheless, melatonin could significantly improve the progressive motility of spermatozoa in MS rats. Swimming caused an increased apoptosis of S group and decreased all antioxidant enzymes. Melatonin could drastically reduce apoptosis and increased these enzymes. Therefore, melatonin seems to induce the production of antioxidant enzymes of testicular tissues and diminish the extent of apoptotic changes caused by forced exercise on the testis, which can, in turn, ameliorate the sperm parameters. © 2017 Blackwell Verlag GmbH.

  14. Antithrombotic Protective Effects of Arg-Pro-Gly-Pro Peptide during Emotional Stress Provoked by Forced Swimming Test in Rats.

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    Grigor'eva, M E; Lyapina, L A

    2017-01-01

    Blood coagulation was enhanced and all factors (total, enzyme, and non-enzyme) of the fibrinolytic system were suppressed in rats in 60 min after forced swimming test. Argininecontaining tetrapeptide glyproline Arg-Pro-Gly-Pro administered prior to this test activated fibrinolysis and prevented hypercoagulation. Administration of this peptide in 5 min after swimming test also enhanced anticoagulant, fibrinolytic, and antithrombotic activity of the blood. Therefore, glyproline Arg-Pro-Gly-Pro exerted both preventive and curative effects on the hemostasis system and prevented enhancement of blood coagulation provoked by emotional stress modeled by forced swimming test.

  15. [Behavior in the forced-swimming test and expression of BDNF and Bcl-xl genes in the rat brain].

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    Berezova, I V; Shishkina, G T; Kalinina, T S; Dygalo, N N

    2011-01-01

    A single exposure of rats to the forced-swimming stress decreased BDNF mRNA levels in the cortex and increased Bcl-xl gene expression in the hippocampus and amygdala 24 h after the stress. The animals demonstrated a depressive-like behavior and elevated blood corticosterone level. There was a significant negative correlation between BDNF mRNA level in the cortex and immobility time during swimming. Repeated exposure to swimming stress caused the elevation of the hippocampal BDNF mRNA level assessed 24 h after the second swimming session. The data suggest that stress-induced down-regulation of cortical BDNF gene expression and behavioral despair in the forced-swimming test may be interrelated. The increase in the BDNF and Bcl-xl mRNA levels may contribute to the mechanisms protecting the brain against negative effects of stress.

  16. Adaptation of the pituitary-adrenal axis to daily repeated forced swim exposure in rats is dependent on the temperature of water.

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    Rabasa, Cristina; Delgado-Morales, Raúl; Gómez-Román, Almudena; Nadal, Roser; Armario, Antonio

    2013-11-01

    Comparison of exposure to certain predominantly emotional stressors reveals a qualitatively similar neuroendocrine response profile as well as a reduction of physiological responses after daily repeated exposure (adaptation). However, particular physical components of the stressor may interfere with adaptation. As defective adaptation to stress can enhance the probability to develop pathologies, we studied in adult male rats (n = 10/group) swimming behavior (struggling, immobility and mild swim) and physiological responses (ACTH, corticosterone and rectal temperature) to daily repeated exposure to forced swim (20 min, 13 d) at 25 or 36 °C (swim25 or swim36). Rats were repeatedly blood-sampled by tail-nick and hormones measured by radioimmunoassay. Some differences were observed between the two swim temperature groups after the first exposure to forced swim: (a) active behaviors were greater in swim25 than swim36 groups; (b) swim25 but not swim36 caused hypothermia; and (c) swim36 elicited the same ACTH response as swim25, but plasma corticosterone concentration was lower for swim36 at 30 min post-swim. After daily repeated exposure, adaptation in ACTH secretion was observed with swim36 already on day 4, whereas with swim25 adaptation was not observed until day 13 and was of lower magnitude. Nevertheless, after repeated exposure to swim25 a partial protection from hypothermia was observed and the two swim conditions resulted in progressive reduction of active behaviors. Thus, daily repeated swim at 25 °C impairs adaptation of the hypothalamic-pituitary-adrenal axis as compared to swim at 36 °C, supporting the hypothesis that certain physical components of predominantly emotional stressors can interfere with the process of adaptation.

  17. Orally administered whole egg demonstrates antidepressant-like effects in the forced swimming test on rats.

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    Nagasawa, Mao; Otsuka, Tsuyoshi; Ogino, Yumi; Yoshida, Junki; Tomonaga, Shozo; Yasuo, Shinobu; Furuse, Mitsuhiro

    2014-08-01

    Several studies have reported that vegetarian diets are associated with a higher prevalence of major depression. Therefore, we hypothesised that the consumption of animal products, especially eggs, may have positive effects on mental health, especially on major depression, because a previous study reported that egg consumption produces numerous beneficial effects in humans. The purpose of the present study was to evaluate the effects of chronic whole-egg treatment on depression-like behaviours in Wistar rats, a control strain, and Wistar Kyoto rats, an animal model of depression. In both the rats, either whole-egg solution (5 ml/kg) or distilled water (5 ml/kg) was orally administrated for 35 days. During these periods, the open-field test (OFT) was conducted on the 21st day, and a forced swimming test (FST) was enforced on the 27th and 28th days. On the 36th day, the plasma and brain were collected. Chronic whole-egg treatment did not affect line crossing in the OFT, whereas it reduced the total duration of immobility in the FST on both strains. Furthermore, interestingly, the results indicated the possibility that whole-egg treatment elevated the incorporation of tryptophan into the brain, and the tryptophan concentration in the prefrontal cortex was actually increased by the treatment. This study demonstrated that whole-egg treatment exerts an antidepressant-like effect in the FST. It is suggested that whole egg may be an excellent food for preventing and alleviating the conditions of major depression.

  18. Antioxidant and Antifatigue Properties of the Aqueous Extract of Moringa oleifera in Rats Subjected to Forced Swimming Endurance Test

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    Lamou, Bonoy; Taiwe, Germain Sotoing; Hamadou, André; Abene; Houlray, Justin; Atour, Mahamat Mey; Tan, Paul Vernyuy

    2016-01-01

    The effects of the aqueous extract of Moringa oleifera on swimming performance and related biochemical parameters were investigated in male Wistar rats (130–132 g). Four groups of rats (16 per group) were fed a standard laboratory diet and given distilled water, 100, 200, or 400 mg/kg of extract, respectively, for 28 days. On day 28, 8 rats from each group were subjected to the forced swimming test with tail load (10% of body weight). The remaining 8 rats per group were subjected to the 90-minute free swim. Maximum swimming time, glycemia, lactamia, uremia, triglyceridemia, hepatic and muscle glycogen, hematological parameters, and oxidative stress parameters (superoxide dismutase, catalase, reduced glutathione, and malondialdehyde) were measured. Results. M. oleifera extract increased maximum swimming time, blood hemoglobin, blood glucose, and hepatic and muscle glycogen reserves. The extract also increased the activity of antioxidant enzymes and decreased the blood concentrations of malondialdehyde. Furthermore, it decreased blood concentrations of lactate, triglycerides, and urea. In conclusion, the antifatigue properties of M. oleifera extract are demonstrated by its ability to improve body energy stores and tissue antioxidant capacity and to reduce the tissue build-up of lactic acid. PMID:26904162

  19. Antioxidant and Antifatigue Properties of the Aqueous Extract of Moringa oleifera in Rats Subjected to Forced Swimming Endurance Test.

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    Lamou, Bonoy; Taiwe, Germain Sotoing; Hamadou, André; Abene; Houlray, Justin; Atour, Mahamat Mey; Tan, Paul Vernyuy

    2016-01-01

    The effects of the aqueous extract of Moringa oleifera on swimming performance and related biochemical parameters were investigated in male Wistar rats (130-132 g). Four groups of rats (16 per group) were fed a standard laboratory diet and given distilled water, 100, 200, or 400 mg/kg of extract, respectively, for 28 days. On day 28, 8 rats from each group were subjected to the forced swimming test with tail load (10% of body weight). The remaining 8 rats per group were subjected to the 90-minute free swim. Maximum swimming time, glycemia, lactamia, uremia, triglyceridemia, hepatic and muscle glycogen, hematological parameters, and oxidative stress parameters (superoxide dismutase, catalase, reduced glutathione, and malondialdehyde) were measured. Results. M. oleifera extract increased maximum swimming time, blood hemoglobin, blood glucose, and hepatic and muscle glycogen reserves. The extract also increased the activity of antioxidant enzymes and decreased the blood concentrations of malondialdehyde. Furthermore, it decreased blood concentrations of lactate, triglycerides, and urea. In conclusion, the antifatigue properties of M. oleifera extract are demonstrated by its ability to improve body energy stores and tissue antioxidant capacity and to reduce the tissue build-up of lactic acid.

  20. Individual differences in the forced swimming test and neurochemical kinetics in the rat brain.

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    Sequeira-Cordero, Andrey; Mora-Gallegos, Andrea; Cuenca-Berger, Patricia; Fornaguera-Trías, Jaime

    2014-04-10

    Individual differences in the forced swimming test (FST) could be associated with differential temporal dynamics of gene expression and neurotransmitter activity. We tested juvenile male rats in the FST and classified the animals into those with low and high immobility according to the amount of immobility time recorded in FST. These groups and a control group which did not undergo the FST were sacrificed either 1, 6 or 24 h after the test. We analyzed the expression of the CRF, CRFR1, BDNF and TrkB in the prefrontal cortex, hippocampus and nucleus accumbens as well as norepinephrine, dopamine, serotonin, glutamate, GABA and glutamine in the hippocampus and nucleus accumbens. Animals with low immobility showed significant reductions of BDNF expression across time points in both the prefrontal cortex and the nucleus accumbens when compared with non-swim control. Moreover, rats with high immobility only showed a significant decrease of BDNF expression in the prefrontal cortex 6h after the FST. Regarding neurotransmitters, only accumbal dopamine turnover and hippocampal glutamate content showed an effect of individual differences (i.e. animals with low and high immobility), whereas nearly all parameters showed significant differences across time points. Correlational analyses suggest that immobility in the FST, probably reflecting despair, is related to prefrontal cortical BDNF and to the kinetics observed in several other neurochemical parameters. Taken together, our results suggest that individual differences observed in depression-like behavior can be associated not only with changes in the concentrations of key neurochemical factors but also with differential time courses of such factors. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Effect of forced swimming stress on count, motility and fertilization capacity of the sperm in adult rats

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    Ghasem Saki

    2009-01-01

    Full Text Available Aims: The purpose of this study was to determine whether 50 days of forced swimming stress applied to adult male rats affects count, motility and fertilization capacity of sperm. Settings and Design: It is a prospective study designed in vitro. Materials and Methods: A total 30 adult male wistar rats were used in this study. All rats were divided into two equal groups (n = 15: (1 control group and (2 experimental group. Animals of the experimental group were submitted to force swimming stress for 3 min in water at 32°C daily for 50 days. Then, all male rats were sacrificed, the right epididymides were removed and sperm concentration and motility were determined. The sperm suspension was added to the ova. Fertilization capacity was assessed by counting two-cell embryos 24-26 h after completion of fertilization in vitro. Statistical Analysis Used: Data are reported as mean ± SD and percentage. The difference between the control and experimental groups was determined by the unpaired t-test. Results: The mean and standard deviation of sperm concentration in the control and experimental groups were 60.8 ± 9.3 10 6 /ml and 20.4 ± 5.3 10 6 /ml, respectively. There was a statistical difference of P < 0.05 between the two groups in terms of sperm concentration. The percentage of motility in the experimental group was significantly different ( P < 0.05. The same results were obtained in case of fertility ( P < 0.05. Stress caused by forced swimming was observed by a significant increase in the latency of the pain response in the hot-plate test ( P < 0.05. Conclusions: These results suggest that forced swimming stress in time course equal or more than spermatogenesis period, i.e. 48-50 days in the rat will be significantly effective to reduce the number and motility of sperms as well as the fertilization capacity.

  2. Glucometabolic effects of single and repeated exposure to forced-swimming stressor in Sprague-Dawley rats.

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    Morakinyo, Ayodele Olufemi; Iranloye, Bolanle Olubusola; Ogunsola, Oluseyi Abimbola

    2018-04-01

    We aimed to evaluate the effects of a single (acute) and repeated (chronic) exposure to forced-swimming stressor on glucose tolerance, insulin sensitivity, lipid profile and glycogen content in male rats. Thirty adult male Sprague-Dawley rats (12 weeks old) were divided randomly into five groups: control group, single exposure (SE) to forced-swim stressor, repeated exposure to forced-swim stressor for 7 days (RE7), 14 days (RE14) and 28 days (RE28). Glucose tolerance test and Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) were undertaken on fasting rats to obtain glucose and insulin profiles. ELISA was performed to assess plasma insulin and corticosterone levels. Total cholesterol, triglyceride, high- and low-density lipoproteins, hepatic and skeletal glycogen content were also determined. Repeated exposure to stressor induced glucose intolerance and insulin resistance in the experimental rats. Results showed that all RE groups exhibited a significantly higher area under the curve compared with others (p=0.0001); similarly, HOMA-IR increased (p=0.0001) in all RE groups compared with control. Prolonged exposure to stressor significantly increased the plasma insulin and corticosterone levels but decreased the glycogen content in the liver and skeletal muscle when compared with the control group. Additionally, chronic stressor significantly increased the total cholesterol and triglyceride levels, however, acute stressor produced significantly elevated high-density lipoproteins level. In conclusion, repeated exposure to forced-swimming stressor induced glucose intolerance and insulin resistance in rats by disrupting the insulin sensitivity as well as heightening the glycogenolysis in the liver and skeletal muscle. Acute stressor was unable to cause glucose intolerance and insulin resistance but it appears that may have a positive effect on the lipid metabolism.

  3. Acute administration of ketamine in rats increases hippocampal BDNF and mTOR levels during forced swimming test.

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    Yang, Chun; Hu, Yi-Min; Zhou, Zhi-Qiang; Zhang, Guang-Fen; Yang, Jian-Jun

    2013-03-01

    Previous studies have shown that a single sub-anesthetic dose of ketamine exerts fast-acting antidepressant effects in patients and in animal models of depression. However, the underlying mechanisms are not totally understood. This study aims to investigate the effects of acute administration of different doses of ketamine on the immobility time of rats in the forced swimming test (FST) and to determine levels of hippocampal brain-derived neurotrophic factor (BDNF) and mammalian target of rapamycin (mTOR). Forty male Wistar rats weighing 180-220 g were randomly divided into four groups (n = 10 each): group saline and groups ketamine 5, 10, and 15 mg/kg. On the first day, all animals were forced to swim for 15 min. On the second day ketamine (5, 10, and 15 mg/kg, respectively) was given intraperitoneally, at 30 min before the second episode of the forced swimming test. Immobility times of the rats during the forced swimming test were recorded. The animals were then decapitated. The hippocampus was harvested for determination of BDNF and mTOR levels. Compared with group saline, administration of ketamine at a dose of 5, 10, and 15 mg/kg decreased the duration of immobility (P < 0.05 for all doses). Ketamine at doses of both 10 and 15 mg/kg showed a significant increase in the expression of hippocampal BDNF (P < 0.05 for both doses). Ketamine given at doses of 5, 10, and 15 mg/kg showed significant increases in relative levels of hippocampal p-mTOR (P < 0.05 for all doses) The antidepressant effect of ketamine might be related to the increased expression of BDNF and mTOR in the hippocampus of rats.

  4. [Influence of estradiol on tryptophan hydroxylase and 5-hydroxytryptamine content in raphe nuclei of rats under forced swimming stress].

    Science.gov (United States)

    Yang, Fu-zhong; Wu, Yan; Zhang, Wei-guo; Cai, Yi-yun; Shi, Shen-xun

    2010-07-20

    To investigate the effect of estradiol (E2) on tryptophan hydroxylase (TPH) and 5-hydroxytryptamine (5-HT) content in raphe nuclei of rats under forced swimming stress and explore the role of estrogen and stress in disease mechanism of depression in women. At Week 3 post-ovariectomy, 35 ovariectomized (OVX) female SD rats were randomly divided into 5 groups (n = 7): non-stress group, control group, estradiol (E2) group and fluoxetine (FLX) group and E2 plus FLX group. Animals were administered with different drugs for 2 weeks. At Day 14, animals except those in the non-stress group were subjected to the 15 min forced swimming test (FST). At 2 hours post-FST, all animals including those in the non-stress group were perfused with 4% paraformaldehyde and brains removed for TPH and 5-HT immunofluorescence staining. We compared the content of TPH and 5-HT by observing and calculating the integrated optical density (IOD) of immunofluorescent-positive signals in raphe nuclei. (1) The IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the control group was significantly lower than that of the non-stress group (P Forced swimming stress can decrease the TPH and 5-HT content in raphe nuclei. Such changes can be prevented by a pre-administration of estradiol. Similar results are observed with antidepressant fluoxetine. These effects may underlie the role of estradiol and stress in the disease mechanism of depression in women.

  5. Effect of intraperitoneal selenium administration on liver glycogen levels in rats subjected to acute forced swimming.

    Science.gov (United States)

    Akil, Mustafa; Bicer, Mursel; Kilic, Mehmet; Avunduk, Mustafa Cihat; Mogulkoc, Rasim; Baltaci, Abdulkerim Kasim

    2011-03-01

    There are a few of studies examining how selenium, which is known to reduce oxidative damage in exercise, influences glucose metabolism and exhaustion in physical activity. The present study aims to examine how selenium administration affects liver glycogen levels in rats subjected to acute swimming exercise. The study included 32 Sprague-Dawley type male rats, which were equally allocated to four groups: Group 1, general control; Group 2; selenium-supplemented control (6 mg/kg/day sodium selenite); Group 3, swimming control; Group 4, selenium-supplemented swimming (6 mg/kg/day sodium selenite). Liver tissue samples collected from the animals at the end of the study were fixed in 95% ethyl alcohol. From the tissue samples buried into paraffin, 5-µm cross-sections were obtained using a microtome, put on a microscope slide, and stained with PAS. Stained preparations were assessed using a Nikon Eclipse E400 light microscope. All images obtained with the light microscope were transferred to a PC and evaluated using Clemex PE 3.5 image analysis software. The highest liver glycogen levels were found in groups 1 and 2 (p swimming exercise can be restored by selenium administration. It can be argued that physiological doses of selenium administration can contribute to performance.

  6. Effect of ginsenoside Rg3 on tyrosine hydroxylase and related mechanisms in the forced swimming-induced fatigue rats.

    Science.gov (United States)

    Xu, Yuxia; Zhang, Peng; Wang, Chu; Shan, Ye; Wang, Dandan; Qian, Fenglei; Sun, Mengwei; Zhu, Cuiqing

    2013-10-28

    Ginsenoside Rg3 has shown multiple pharmacological activities and been considered as one of the most promising approaches for fatigue treatment. However, little is known about the cellular and molecular mechanisms of Rg3 on anti-fatigue and the effect of Rg3 on dopaminergic system has not been reported yet. The major aim of this study is to investigate the effect of Rg3 on TH expression and the related biochemical parameters, such as PKAα, ERK1/2, Akt and α-synuclein in brain of fatigue rats. Weight-loaded forced swimming was performed to establish an animal model of fatigue. Rg3 (10mg/kg, 50mg/kg and 100mg/kg) was intragastrically administrated before swimming. The effect of Rg3 on the expression and phosphorylation of TH and TH-related proteins in fatigue rats or in SH-SY5Y cells was assessed with western blotting. HPLC was used to examine the level of DA and DOPAC in the fatigue rats tissues. TH and phosphorylated TH were decreased in different brain regions of which ventral midbrain were less affected in weight-loaded forced swimming rats. Pretreatment with Rg3 significantly suppressed fatigue-induced decrease expression of TH and TH phosphorylation. Also treatment with Rg3 reversed the decrease expression of PKAα as well as the phosphorylation of ERK1/2 and Akt which were induced by weight-loaded forced swimming. Moreover, weight-loaded swimming could induce the increase expression of α-synuclein in hippocampus and midbrain, while suppressed α-synuclein expression in striatum and prefrontal cortex. Furthermore, Rg3 could induce the increase of TH expression and phosphorylation which was accompanied with elevated expression and phosphorylation of related kinase proteins in vitro, while the inhibitors of kinase proteins could suppress these effects of Rg3. In addition, HPLC results showed that Rg3 could reverse the weight-loaded swimming-induced increase of DOPAC/DA ratio. Our data suggest that fatigue can induce the decrease of DA which might partially

  7. Repeated rat-forced swim test: reducing the number of animals to evaluate gradual effects of antidepressants.

    Science.gov (United States)

    Mezadri, T J; Batista, G M; Portes, A C; Marino-Neto, J; Lino-de-Oliveira, C

    2011-02-15

    The forced swim test (FST) is a pre-clinical test to short and long term treatment with antidepressant drugs (ADT), which requires between-subject designs. Herein a modified protocol of the FST using within-subject design (repeated rat-FST) was evaluated. Male Wistar rats were submitted to 15 min of swimming (Day 1: pretest) followed by three subsequent 5 min-swimming tests one week apart (Day 2: test, Day 7: retest 1, Day 14: retest 2). To determine the temporal and factorial characteristics of the variables scored in the repeated rat-FST, the protocol was carried out in untreated animals (E1). To validate the method, daily injections of Fluoxetine (FLX, 2.5mg/kg, i.p.) or saline were given over a 2-week period (E2). Tests and retests have been videotaped for further register of the latency, frequency and duration of behaviors. Over retesting the latency to immobility decreased whereas duration of immobility tended to increase. Factorial analysis revealed that the test, the retest 1 as well as the retest 2 have variables suitable to detection of antidepressant-like effects of ADT. Compared to saline, FLX chronically administrated reduced duration of immobility whereas increased duration of swimming in retest 2. The data suggest that repeated rat-FST detected the gradual increase in the efficacy of low doses of FLX over time. Therefore, repeated rat-FST seemed suitable to detect short and long term effects of selective serotonin reuptake inhibitors, or other ADT, thus reducing the number of animals used in the screenings of this type of compounds. © 2010 Elsevier B.V. All rights reserved.

  8. Repeated forced swimming impairs prepulse inhibition and alters brain-derived neurotrophic factor and astroglial parameters in rats.

    Science.gov (United States)

    Borsoi, Milene; Antonio, Camila Boque; Müller, Liz Girardi; Viana, Alice Fialho; Hertzfeldt, Vivian; Lunardi, Paula Santana; Zanotto, Caroline; Nardin, Patrícia; Ravazzolo, Ana Paula; Rates, Stela Maris Kuze; Gonçalves, Carlos-Alberto

    2015-01-01

    Glutamate perturbations and altered neurotrophin levels have been strongly associated with the neurobiology of neuropsychiatric disorders. Environmental stress is a risk factor for mood disorders, disrupting glutamatergic activity in astrocytes in addition to cognitive behaviours. Despite the negative impact of stress-induced neuropsychiatric disorders on public health, the molecular mechanisms underlying the response of the brain to stress has yet to be fully elucidated. Exposure to repeated swimming has proven useful for evaluating the loss of cognitive function after pharmacological and behavioural interventions, but its effect on glutamate function has yet to be fully explored. In the present study, rats previously exposed to repeated forced swimming were evaluated using the novel object recognition test, object location test and prepulse inhibition (PPI) test. In addition, quantification of brain-derived neurotrophic factor (BDNF) mRNA expression and protein levels, glutamate uptake, glutathione, S100B, GluN1 subunit of N-methyl-D-aspartate receptor and calmodulin were evaluated in the frontal cortex and hippocampus after various swimming time points. We found that swimming stress selectively impaired PPI but did not affect memory recognition. Swimming stress altered the frontal cortical and hippocampal BDNF expression and the activity of hippocampal astrocytes by reducing hippocampal glutamate uptake and enhancing glutathione content in a time-dependent manner. In conclusion, these data support the assumption that astrocytes may regulate the activity of brain structures related to cognition in a manner that alters complex behaviours. Moreover, they provide new insight regarding the dynamics immediately after an aversive experience, such as after behavioural despair induction, and suggest that forced swimming can be employed to study altered glutamatergic activity and PPI disruption in rodents. Copyright © 2014. Published by Elsevier Inc.

  9. Influence of enrichment on behavioral and neurogenic effects of antidepressants in Wistar rats submitted to repeated forced swim test.

    Science.gov (United States)

    Possamai, Fernanda; dos Santos, Juliano; Walber, Thais; Marcon, Juliana C; dos Santos, Tiago Souza; Lino de Oliveira, Cilene

    2015-04-03

    Repeated forced swimming test (rFST) may detect gradual effects of antidepressants in adult rats. Antidepressants, as enrichment, affected behavior and neurogenesis in rats. However, the influence of enrichment on behavioral and neurogenic effects of antidepressants is unknown. Here, effects of antidepressants on rFST and hippocampal neurogenesis were investigated in rats under enriched conditions. Behaviors of male Wistar rats, housed from weaning in standard (SE) or enriched environment (EE), were registered during rFST. The rFST consisted of 15min of swimming (pretest) followed by 5min of swimming in the first (test), seventh (retest 1) and fourteenth (retest 2) days after pretest. One hour before the test, rats received an intraperitoneal injection of saline (1ml/kg), fluoxetine (2.5mg/kg) or imipramine (2.5 or 5mg/kg). These treatments were performed daily until the day of the retest 2. After retest 2, rats were euthanized for the identification of markers for neurogenesis in the hippocampus. Fluoxetine or imipramine decreased immobility in retests 1 and 2, as compared to saline. EE abolished these differences. In EE, fluoxetine or imipramine (5mg/kg) reduced immobility time in retest 2, as compared to the test. Independent of the housing conditions, fluoxetine and imipramine (5mg/kg) increased the ratio of immature neurons per progenitor cell in the hippocampus. In summary, antidepressants or enrichment counteracted the high immobility in rFST. Enrichment changed the effects of antidepressants in rFST depending on the type, and the dose of a substance but failed to change neurogenesis in control or antidepressant treated-rats. Effects of antidepressants and enrichment on rFST seemed neurogenesis-independent. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats

    Science.gov (United States)

    Arndt, David L.; Peterson, Christy J.; Cain, Mary E.

    2015-01-01

    Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression. PMID:26154768

  11. Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

    Directory of Open Access Journals (Sweden)

    David L Arndt

    Full Text Available Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC, standard (SC, or isolated (IC conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p. was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg rats and EC-fluoxetine (20 mg/kg rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

  12. Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

    Science.gov (United States)

    Arndt, David L; Peterson, Christy J; Cain, Mary E

    2015-01-01

    Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

  13. Antidepressant-Like Effects of Lindera obtusiloba Extracts on the Immobility Behavior of Rats in the Forced Swim Test

    Directory of Open Access Journals (Sweden)

    Dong Wook Lim

    2016-02-01

    Full Text Available Lindera obtusiloba extracts are commonly used as an alternative medicine due to its numerous health benefits in Korea. However, the antidepressant-like effects of L. obtusiloba extracts have not been fully elucidated. In this study, we aimed to determine whether L. obtusiloba extracts exhibited antidepressant-like activity in rats subjected to forced swim test (FST-induced depression. Acute treatment of rats with L. obtusiloba extracts (200 mg/kg, p.o. significantly reduced immobility time and increased swimming time without any significant change in climbing. Rats treated with L. obtusiloba extracts also exhibited a decrease in the limbic hypothalamic-pituitary-adrenal (HPA axis response to the FST, as indicated by attenuation of the corticosterone response and decreased c-Fos immunoreactivity in the hippocampus CA3 region. In addition, L. obtusiloba extracts, at concentrations that were not affected by cell viability, significantly decreased luciferase activity in response to cortisol in a concentration-dependent manner by the glucocorticoid binding assay in HeLa cells. Our findings suggested that the antidepressant-like effects of L. obtusiloba extracts were likely mediated via the glucocorticoid receptor (GR. Further studies are needed to evaluate the potential of L. obtusiloba extracts as an alternative therapeutic approach for the treatment of depression.

  14. Reduced effectiveness of escitalopram in the forced swimming test is associated with increased serotonin clearance rate in food restricted rats

    Science.gov (United States)

    France, CP; Li, J-X; Owens, WA; Koek, W; Toney, GM; Daws, LC

    2012-01-01

    Efficacy of antidepressant drugs is often limited. One of the limiting factors may be diet. This study shows that the effect of escitalopram in the forced swimming test is diminished in rats by food restriction that decreased body weight by 8%. The primary target for escitalopram is the serotonin (5-HT) transporter. Using high-speed chronoamperometry to measure 5-HT clearance in vivo in rats fed the same food restricted diet, the rate of 5-HT clearance from extracellular fluid in brain was dramatically increased. Increased 5-HT transporter function under conditions of dietary restriction might contribute to the decreased effect of escitalopram. These results suggest that diet plays an integral role in determining efficacy of antidepressant drugs, and might well generalize to other psychoactive drugs that impinge upon the 5-HT transporter. PMID:19419596

  15. Effect of co-administration of fluoxetine and amantadine on immunoendocrine parameters in rats subjected to a forced swimming test.

    Science.gov (United States)

    Rogóz, Zofia; Kubera, Marta; Rogóz, Katarzyna; Basta-Kaim, Agnieszka; Budziszewska, Bogusława

    2009-01-01

    Considerable attention has been paid to a possible role of immunological dysregulation in the pathogenesis of depression. It has been reported that combined administration of antidepressant drugs and the non-competitive NMDA receptor antagonist amantadine reduces immobility time in the forced swimming test (FST). Moreover, preliminary clinical data show that such a combination of drugs has a beneficial effect on treatment-resistant depressed patients. Since immune activation and a pro-inflammatory response are clearly evident in treatment-resistant depression, the aim of the present study was to examine the effect of a combination of the antidepressant fluoxetine and amantadine on immunoendocrine parameters in rats subjected to the forced swimming test. The obtained results revealed synergistic antidepressant effects of the combined administration of fluoxetine (10 mg/kg) and amantadine (10 mg/kg) - drugs otherwise ineffective when given separately in the above doses. Antidepressant activity was accompanied with a significant decrease in the capacity of splenocytes to proliferate in response to concanavalin A. Moerover, fluoxetine and the combination of amantadine and fluoxetine reduced relative spleen weight in rats subjected to the FST, compared to rats treated with the vehicle. The combination of amantadine and fluoxetine enhanced the production of the negative immunoregulator interleukin-10 (but not interferon-gamma) in rats subjected to the FST. The exposure to the FST produced an increase in plasma corticosterone levels, which was significantly attenuated by pretreatment with fluoxetine and amantadine. In summary, the antidepressive efficacy of a combination of fluoxetine and amantadine given in suboptimal doses may be related to the negative immunoendocrine effects of these drugs.

  16. The folic acid combined with 17-β estradiol produces antidepressant-like actions in ovariectomized rats forced to swim.

    Science.gov (United States)

    Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia; Olivera-López, Jorge I; Jaramillo, M Teresa

    2011-01-15

    Folic acid or 17-β estradiol produces antidepressant effects, either alone or combined with several antidepressants. However, the antidepressant-like actions of folic acid combined with 17-β estradiol in the forced swimming test (FST) have not been tested before. Thus, in the present study, ovariectomized female rats received folic acid (5.0 nmol/i.c.v., Pfluoxetine (20.0mg/kg, Pswimming behavior when they were tested in the FST. Combination of subthreshold doses of folic acid (2.5 nmol/i.c.v.; or 25.0mg/kg, p.o.) with subthreshold doses of 17-β estradiol (5.0 μg/rat, Pfluoxetine (15.0mg/kg, Pfluoxetine in the FST reduced immobility in the FST. These antidepressant-like actions probably were due to modifications of the serotonergic system since swimming behavior was increased and these effects were cancelled by ketanserin. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Melatonin improve the sperm quality in forced swimming test induced oxidative stress in nandrolone treated Wistar rats.

    Science.gov (United States)

    Minaii, Bagher; Moayeri, Ardeshir; Shokri, Saeed; Habibi Roudkenar, Mehryar; Golmohammadi, Taghi; Malek, Fatemeh; Barbarestani, Mohammad

    2014-01-01

    This study investigates the effects of melatonin on the sperm quality and testis weight after the combination of swimming exercise and nandrolone decanoate (DECA). Two groups of male Wistar rats were treated for eight weeks as follows; group A consist of CO (control), Sham, N (DECA), S (swimming) and NS (DECA plus swimming); and group B: Sham M (sham melatonin), M (melatonin), MN (melatonin plus DECA), MS (melatonin plus swimming), MNS (melatonin, DECA plus swimming). The motility of sperm was significantly improved in melatonin groups in comparison to N, S and NS groups (P≤0.05).  The left testes weight was decreased in N, NS and MNS groups, and the right testes weight was decreased in N,S,NS, MS and MNS groups in compare with the control group. This study concluded that melatonin probably could improve the sperm motility and sex organs weight after the combination of DECA and exercise.

  18. Chronic treatment with fluoxetine and sertraline prevents forced swimming test-induced hypercontractility of rat detrusor muscle.

    Science.gov (United States)

    Bilge, Sirri; Bozkurt, Ayhan; Bas, Duygu B; Aksoz, Elif; Savli, Evren; Ilkaya, Fatih; Kesim, Yuksel

    2008-01-01

    Serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors represent important targets for the development of new treatments for detrusor overactivity and urinary incontinence. The present study was undertaken to investigate the effects of the forced swimming test (FST) on the contractile response of isolated rat detrusor muscle and to examine the effects of in vivo treatments of fluoxetine and sertraline on altered detrusor muscle contractility. Fluoxetine (20 mg/kg ip) and sertraline (10 mg/kg ip) were administered once a day for 14 days. Rats were exposed to the FST on the 15th day. After the test, detrusor muscles were removed and placed in organ baths, and the contraction responses induced by carbachol, potassium chloride (KCl) and electrical field stimulation (EFS) were recorded. The contractile responses of detrusor muscle strips to carbachol and electrical field stimulation were found to be increased at all carbachol doses and frequencies, respectively. FST also increased the contractile responses to KCl, which is used to test the differences in postreceptor-mediated contractions. The hypercontractile responses of detrusor strips to carbachol, EFS and KCl were abolished by treatment with both fluoxetine and sertraline. These treatments also decreased the immobility duration in the FST consistent with an antidepressant-like effect in this test. The results of this study provide the first evidence that FST increases contractility of the rat detrusor muscle, and this hypercontractility was abolished by chronic treatments of fluoxetine and sertraline at antidepressant doses by decreasing the postreceptor-mediated events.

  19. [Effect of Acupuncture Intervention on c-jun N-terminal Kinase Signaling in the Hippocampus in Rats with Forced Swimming Stress].

    Science.gov (United States)

    Guo, Yu; Xu, Ke; Bao, Wu-ye; Wang, Yu; Zhang, Xu-hui; Xu, Ming-min; Yu, Miao; Zhang, Chun-tao; Zhao, Bing-cong; Wu, Ji-hong; Tu, Ya

    2016-02-01

    To observe the effect of acupuncture on c-jun N-terminal Kinase (JNK) signaling in the hippocampus in rats with forced-swimming stress, so as to reveal its underlying mechanism in relieving depression-like motor response. Forty-eight Sprague-Dawley rats were randomly divided into 8 groups as control, control + JNK inhibitor (SP 600125) , model, model + SP 600125, acupuncture, acupuncture + SP 600125, Fluoxetine (an anti-depressant) , and Fluoxetine + SP 600125 (n = 6 in each group). The depression-like behavior (immobility) model was established by forcing the rat to swim in a glass-cylinder and solitary raise. Acupuncture stimulation was applied to "Baihui" (GV-20) and "Yintang" (GV 29) for 20 min before forced swimming and once again 24 h later.. The rats of the Fluoxetine and Fluoxetine+ SP 600125 groups were treated by intragastric administration of fluoxetine 10 mL (1.8 mg)/kg before forced swimming and once again 24 h thereafter. The rats of the model + SP 600125 and acupuncture + SP 600125 groups were treated by intraperitoneal injection of SP 600125 (10 mg/kg) 90 min before forced swimming and 30 min before acupuncture intervention, respectively. The immobility duration of rats in the water glass-cylinder was used to assess their depression-like behavior response. The expression levels of protein kinase kinase 4 (MKK 4), MKK 7, JNK, and phosphorylated JNK (p-JNK) in the hippocampus were detected by Western blot. Compared to the control group, the duration of immobility, and the expression levels of hippocampal MKK 4, MKK 7, and p-JNK proteins were significantly increased in the model group (P Fluoxetine and Fluoxetine + SP 600125 groups, the expression levels of hippocampal MKK 4 and MKK 7 proteins in the Fluoxetine + SP 600125 group, and those of p-JNK protein in the acupuncture, acupuncture + SP 600125, model + SP 600125, Fluoxetine and Fluoxetine + SP 600125 groups were considerably decreased (P Fluoxetine and Fluoxetine + SP 600125 groups in the

  20. Active coping of prenatally stressed rats in the forced swimming test: involvement of the Nurr1 gene.

    Science.gov (United States)

    Montes, Pedro; Ruiz-Sánchez, Elizabeth; Calvillo, Minerva; Rojas, Patricia

    2016-09-01

    Depending on genetic predisposition, prenatal stress may result in vulnerability or resilience to develop psychiatric disorders in adulthood. Nurr1 is an immediate early gene, important in the brain for the stress response. We tested the hypothesis that prenatal stress and the decrease of hippocampal Nurr1 alter offspring behavioral responses in the forced swimming test (FST). Pregnant Wistar rats were exposed to restraint stress (45 min, thrice daily) from gestation day 14. Prenatally stressed (PS) and non-prenatally stressed (NPS) male offspring were treated bilaterally with a Nurr1 antisense oligodeoxynucleotide (ODN; or control) into the hippocampus at 97 d of age. After 1 h, the rats were exposed to the FST (acute stressor) to analyze their behavioral responses. Thirty minutes after the FST, we analyzed the gene expression of Nurr1, Bdnf and Nr3c1 (genes for Nurr1, brain-derived neurotrophic factor (BDNF) and glucocorticoid receptor (GR), respectively) in the hippocampus, prefrontal cortex (PFC) and hypothalamus. Results showed that the decrease of hippocampal Nurr1 after the antisense ODN in adult NPS rats induces immobility (indicating depressive-like behavior). The PS adult rats, including the group with decreased hippocampal Nurr1, presented low immobility in the FST. This low immobility was concordant with maintenance of Nurr1 and Bdnf expression levels in the three analyzed brain regions; Nr3c1 gene expression was also maintained in the PFC and hypothalamus. These findings suggest that Nurr1 and associated genes could participate in the brain modifications induced by prenatal stress, allowing active coping (resilience) with acute stress in adulthood.

  1. Effect of long-term intraperitoneal zinc administration on liver glycogen levels in diabetic rats subjected to acute forced swimming.

    Science.gov (United States)

    Bicer, Mursel; Gunay, Mehmet; Akil, Mustafa; Avunduk, Mustafa Cihat; Mogulkoc, Rasim; Baltaci, Abdulkerim Kasim

    2011-03-01

    This study aims to examine the effect of zinc administration on liver glycogen levels of rats in which diabetes was induced with streptozotocin and which were subjected to acute swimming exercise. The study was conducted on 80 adult Sprague-Dawley male rats, which were equally allocated to eight groups: group 1, general control; group 2, zinc-administrated control; group 3, zinc-administrated diabetic control; group 4, swimming control; group 5, zinc-administrated swimming; group 6, zinc-administrated diabetic swimming; group 7, diabetic swimming; group 8, diabetic control group. In order to induce diabetes, animals were injected with 40 mg/kg intraperitoneal (ip) streptozotocin. The injections were repeated in the same dose after 24 h. Animals which had blood glucose at or above 300 mg/dl 6 days after the last injections were accepted as diabetic. Zinc was administrated ip for 4 weeks as 6 mg/kg/day per rat. Hepatic tissue samples taken from the animals at the end of the study were fixed in 95% ethyl alcohol. Cross sections of 5 µm thickness, taken by the help of a microtome from the tissue samples buried in paraffin, were placed on a microscope slide and stained with periodic acid-Schiff and evaluated by light microscope. All microscopic images were transferred to a PC and assessed with the help of Clemex PE3.5 image analysis software. The lowest liver glycogen levels in the study were obtained in groups 3, 4, 6, 7, and 8. Liver glycogen levels in group 5 were higher than groups 3, 4, 6, 7, and 8, but lower than groups 1 and 2 (p swimming exercise were restored by zinc administration and that diabetes induced in rats prevented the protective effect of zinc.

  2. Concomitant administration of fluoxetine and amantadine modulates the activity of peritoneal macrophages of rats subjected to a forced swimming test.

    Science.gov (United States)

    Roman, Adam; Rogóz, Zofia; Kubera, Marta; Nawrat, Dominika; Nalepa, Irena

    2009-01-01

    Recent studies show that administration of a non-competitive NMDA receptor antagonist, amantadine (AMA), potentiates the action of antidepressant drugs. Since antidepressants may modulate functioning of the immune system and activation of a pro-inflammatory response in depressive disorders is frequently reported, the aim of the present study was to examine whether a combined administration of AMA and the antidepressant, fluoxetine (FLU), to rats subsequently subjected to a forced swimming test (FST) modifies the parameters of macrophage activity, directly related to their immunomodulatory functions, i.e., arginase (ARG) activity and synthesis of nitric oxide (NO). We found that 10 mg/kg AMA and 10 mg/kg FLU, ineffective in FST for antidepressant-like activity when administered alone, increased the ARG/NO ratio in macrophages when administered concomitantly. This effect was accompanied by a decrease of cellular adherence. Concurrently, the basal metabolic activity of the cells measured with reduction of resazurin, and intracellular host defense as assessed by a synthesis of superoxide anion, were not affected by such antidepressive treatment. Our data indicate that co-administration of AMA and FLU decreases the pro-inflammatory properties of macrophages and causes a redirection of immune response toward anti-inflammatory activity, as one can anticipate in the case of an effective antidepressive treatment.

  3. Inhibition of the CRF1 receptor influences the activity of antidepressant drugs in the forced swim test in rats.

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    Wróbel, Andrzej; Serefko, Anna; Szopa, Aleksandra; Rojek, Karol; Poleszak, Ewa; Skalicka-Woźniak, Krystyna; Dudka, Jarosław

    2017-08-01

    Hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA) and impairment of the central corticotropin-releasing factor (CRF) system are factors in the pathogenesis of depression. Though several antagonists of the CRF 1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between CRF 1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of SN003, a CRF 1 receptor blocker, on the activity of imipramine and fluoxetine in the forced swim test (FST) in rats which presented some signs of depression. The experiments were carried out on female Wistar rats subjected to 14-day subcutaneous corticosterone (CORT) administration (20 mg/kg/day). The antidepressant-like effect was determined by the FST and the CRF levels in the hypothalamus, amygdala, and peripheral blood were measured by a high-sensitivity immunoenzymatic test. SN003 (0.5 mg/kg) potentiated the antidepressant-like effect of imipramine (15 mg/kg) and fluoxetine (7.5 mg/kg). Moreover, the co-administration of the tested agents abolished CORT-induced increase in CRF levels in the examined biological material more profoundly than monotherapy. Our present findings give further evidence that the blockage of CRF action may be useful in the treatment of mood disorders. The concurrent use of well-known antidepressants with CRF 1 receptor antagonists could be beneficial in terms of safety, since it requires lower doses of the applied agents.

  4. Effects of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in rats subjected to the forced swim test.

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    Rogóz, Zofia; Skuza, Grazyna; Leśkiewicz, Monika; Budziszewska, Bogusława

    2008-01-01

    Major depression is frequently associated with hyperactivity of the hypothalamic-pituitary-adrenocortical axis, and glucocorticoid synthesis inhibitors have been shown to exert antidepressant action. The aim of the present study was to examine the effect of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in male Wistar rats subjected to the forced swim test. Metyrapone alone (50 mg/kg, but not 25 mg/kg) reduced the immobility time of rats in the forced swim test; moreover, both doses tested (25 and 50 mg/kg), dose-dependently decreased the stress-induced plasma corticosterone concentration. Joint administration of fluoxetine or tianeptine (10 mg/kg) and metyrapone (25 mg/kg - a dose inactive per se) exhibited antidepressant-like activity in the forced swim test in rats. WAY 100636 (a 5-HT(1A) antagonist), but not prazosin (an alpha(1)-adrenergic antagonist), used in doses ineffective in the forced swim test, inhibited the antidepressant-like effect induced by co-administration of fluoxetine or tianeptine with metyrapone (25 mg/kg). Combined treatment of fluoxetine or tianeptine and metyrapone inhibited stress-induced corticosterone secretion to a similar extent as metyrapone alone. The obtained results indicate that metyrapone potentiates the antidepressant-like activity of fluoxetine or tianeptine and that, among other mechanisms, 5-HT(1A) receptors may play some role in this effect. Moreover, metyrapone exerts a beneficial effect on the stress-induced increase in plasma corticosterone concentration. These findings suggest that the co-administration of metyrapone and an antidepressant drug may be useful for the treatment of drug-resistant depression and/or depression associated with a high cortisol level.

  5. Tipepidine, a non-narcotic antitussive, exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone-treated rats.

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    Kawaura, Kazuaki; Ogata, Yukino; Honda, Sokichi; Soeda, Fumio; Shirasaki, Tetsuya; Takahama, Kazuo

    2016-04-01

    We investigated whether tipepidine exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone (ACTH)-treated rats, which is known as a treatment-resistant depression model, and we studied the pharmacological mechanisms of the effects of tipepidine. Male Wistar rats (5-7 weeks old) were used in this study. Tipepidine (20 and 40 mg/kg, i.p.) decreased the immobility time in the forced swimming test in ACTH-treated rats. The anti-immobility effect of tipepidine was blocked by a catecholamine-depleting agent, alpha-methyl-p-tyrosine (300 mg/kg, s.c.), but not by a serotonin-depleting agent, p-chlorophenylalanine. The anti-immobility effect of tipepidine was also blocked by a dopamine D1 receptor antagonist, SCH23390 (0.02 mg/kg, s.c.) and an adrenaline α2 receptor antagonist, yohimbine (2 mg/kg, i.p.). In microdialysis technique, tipepidine (40 mg/kg, i.p.) increased the extracellular dopamine level of the nucleus accumbens (NAc) in ACTH-treated rats. These results suggest that tipepidine exerts an antidepressant-like effect in the forced swimming test in ACTH-treated rats, and that the effect of tipepidine is mediated by the stimulation of dopamine D1 receptors and adrenaline α2 receptors. The results also suggest that an increase in the extracellular dopamine level in the NAc may be involved in the antidepressant-like effect of tipepidine in ACTH-treated rats. Copyright © 2016. Published by Elsevier B.V.

  6. Antifatigue Effect of Luteolin-6-C-Neohesperidoside on Oxidative Stress Injury Induced by Forced Swimming of Rats through Modulation of Nrf2/ARE Signaling Pathways

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    Fang-fang Duan

    2017-01-01

    Full Text Available Luteolin-6-C-neohesperidoside (LN is a flavonoid isolated from moso bamboo leaf. This study was performed to evaluate the antifatigue effect of LN on a rat model undergoing the weight-loaded forced swimming test (FST. Briefly, male Sprague-Dawley rats (20–22 weeks old were forced to undertake exhaustive swimming every other day for 3 weeks. Each swimming session was followed by the administration of distilled water, LN (25–75 mg/kg, or ascorbic acid (100 mg/kg 1 h later. Oral administration of LN significantly improved exercise endurance; normalized alterations in energy metabolic markers; and decreased serum lactic acid, lactate dehydrogenase, and blood urea nitrogen levels of rats that underwent FST. Moreover, LN enhanced the activities of antioxidant enzymes and antioxidant capacity, as measured by enzyme activity assays, RT-PCR, and Western blotting, as well as decreasing the levels of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1β (IL-1β, and IL-6 and increasing the level of anti-inflammatory (IL-10 in the liver and skeletal muscle. These results suggested that LN reduces both physical and mental effects of chronic fatigue, probably by attenuating oxidative stress injury and inflammatory responses in the liver and skeletal muscle. This study thus supports the use of LN in functional foods for antifatigue and antioxidant effects.

  7. Antifatigue Effect of Luteolin-6-C-Neohesperidoside on Oxidative Stress Injury Induced by Forced Swimming of Rats through Modulation of Nrf2/ARE Signaling Pathways.

    Science.gov (United States)

    Duan, Fang-Fang; Guo, Ying; Li, Jing-Wan; Yuan, Ke

    2017-01-01

    Luteolin-6-C-neohesperidoside (LN) is a flavonoid isolated from moso bamboo leaf. This study was performed to evaluate the antifatigue effect of LN on a rat model undergoing the weight-loaded forced swimming test (FST). Briefly, male Sprague-Dawley rats (20-22 weeks old) were forced to undertake exhaustive swimming every other day for 3 weeks. Each swimming session was followed by the administration of distilled water, LN (25-75 mg/kg), or ascorbic acid (100 mg/kg) 1 h later. Oral administration of LN significantly improved exercise endurance; normalized alterations in energy metabolic markers; and decreased serum lactic acid, lactate dehydrogenase, and blood urea nitrogen levels of rats that underwent FST. Moreover, LN enhanced the activities of antioxidant enzymes and antioxidant capacity, as measured by enzyme activity assays, RT-PCR, and Western blotting, as well as decreasing the levels of proinflammatory cytokines such as tumor necrosis factor- α , interleukin-1 β (IL-1 β ), and IL-6 and increasing the level of anti-inflammatory (IL-10) in the liver and skeletal muscle. These results suggested that LN reduces both physical and mental effects of chronic fatigue, probably by attenuating oxidative stress injury and inflammatory responses in the liver and skeletal muscle. This study thus supports the use of LN in functional foods for antifatigue and antioxidant effects.

  8. The antidepressant-like effects of topiramate alone or combined with 17β-estradiol in ovariectomized Wistar rats submitted to the forced swimming test.

    Science.gov (United States)

    Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia; Olivera-López, Jorge I; Jaramillo, M Teresa

    2014-09-01

    There is a significant delay in the clinical response of antidepressant drugs, and antidepressant treatments produce side effects. We examined the relationship between 17β-estradiol and topiramate in ovariectomized Wistar rats submitted to the forced swimming test (FST). Topiramate was administered alone or combined with 17β-estradiol to ovariectomized rats submitted to the FST. Topiramate (20 mg/kg, P swimming; these effects were antagonized by finasteride (50 mg/kg). In interaction experiments, topiramate (10 mg/kg) plus 17β-estradiol (5 micrograms per rat; P swimming behavior. Besides, 17β-estradiol (2.5 micrograms per rat) shortened the onset of the antidepressant-like effects of topiramate (P < 0.05). In the open field test, topiramate alone or combined with 17β-estradiol (P < 0.05) reduced locomotion. Topiramate alone or combined with 17β-estradiol produced antidepressant-like actions; and 17β-estradiol shortened the onset of the antidepressant-like effects of topiramate.

  9. Noradrenergic neurotransmission within the bed nucleus of the stria terminalis modulates the retention of immobility in the rat forced swimming test.

    Science.gov (United States)

    Nagai, Michelly M; Gomes, Felipe V; Crestani, Carlos C; Resstel, Leonardo B M; Joca, Sâmia R L

    2013-06-01

    The bed nucleus of the stria terminalis (BNST) is a limbic structure that has a direct influence on the autonomic, neuroendocrine, and behavioral responses to stress. It was recently reported that reversible inactivation of synaptic transmission within this structure causes antidepressant-like effects, indicating that activation of the BNST during stressful situations would facilitate the development of behavioral changes related to the neurobiology of depression. Moreover, noradrenergic neurotransmission is abundant in the BNST and has an important role in the regulation of emotional processes related to the stress response. Thus, this study aimed to test the hypothesis that activation of adrenoceptors within the BNST facilitates the development of behavioral consequences of stress. To investigate this hypothesis, male Wistar rats were stressed (forced swimming, 15 min) and 24 h later received intra-BNST injections of vehicle, WB4101, RX821002, CGP20712, or ICI118,551, which are selective α(1), α(2), β(1), and β(2) adrenoceptor antagonists, respectively, 10 min before a 5-min forced swimming test. It was observed that administration of WB4101 (10 and 15 nmol), CGP20712 (5 and 10 nmol), or ICI118,551 (5 nmol) into the BNST reduced the immobility time of rats subjected to forced swimming test, indicating an antidepressant-like effect. These findings suggest that activation of α(1), β(1), and β(2) adrenoceptors in the BNST could be involved in the development of the behavioral consequences of stress. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins.

  10. Antidepressant-like effects of Gan-Mai-Dazao-Tang via monoamine regulatory pathways on forced swimming test in rats.

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    Huang, Hsiang-Ling; Lim, Swee-Ling; Lu, Kuan-Hung; Sheen, Lee-Yan

    2018-01-01

    Depression is a highly prevalent and recurrent mental disorder that impacts all aspects of human life. Undesirable effects of the antidepressant drugs led to the development of complementary and alternative therapies. Gan-Mai-Da-Zao-Tang (, gān mài dà zǎo tang) is a traditional herbal formula commonly used for the treatment of depression, but lack of scientific proof on its mechanism. It consisted of Glycyrrhiza uralensis Fisch. (licorice), Triticum aestivum L. (wheat) and Zizphus jujuba Mill. (jujube). The objective of this study is to investigate the antidepressant effects of Gan-Mai-Dazao-Tang and its ingredients in rats exposed to forced swimming test (FST). The 72 of male Nerl: Wistar rats (8 weeks old) were randomized into control (10 mL/kg bw H 2 O), licorice (0.4 g/kg bw), wheat (1.6 g/kg bw), jujube (0.5 g/kg bw), Gan-Mai-Da-Zao-Tang (2.5 g/kg bw of licorice: wheat: jujube in ratio of 5:20:6) and Prozac (18 mg/kg bw) groups. Samples were administered by oral gavage for 21 days. FST was performed on 21st day, with 15 min for pretest followed by 5 min for real test. Then, the animals were sacrificed and brain tissues were collected for monoamines analyses. The Gan-Mai-Da-Zao-Tang (LWJ) showed significantly down-regulation of immobility time, 3,4-dihydroxyphenylacetic acid (DOPAC) and DOPAC/dopamine (DA) turnover rates, and also enhanced the concentration of serotonin (5-HT) and DA in brain tissues, as compared with the control. The LWJ stated the potent antidepressant-like effect by modulating these monoamines concentration, while the licorice, wheat and jujube did not reported significant results as compared with control group. The positive control (Prozac) was noted with significantly reduction in body weight and appetite. In conclusion, the antidepressant-like effects of LWJ might be mediated by the regulation of monoamine neurotransmitters. Thus, it could beneficial in depression treatment as a complementary approach.

  11. Antidepressant-like effects of Gan-Mai-Dazao-Tang via monoamine regulatory pathways on forced swimming test in rats

    Directory of Open Access Journals (Sweden)

    Hsiang-Ling Huang

    2018-01-01

    Full Text Available Depression is a highly prevalent and recurrent mental disorder that impacts all aspects of human life. Undesirable effects of the antidepressant drugs led to the development of complementary and alternative therapies. Gan-Mai-Da-Zao-Tang (甘麥大棗湯, gān mài dà zǎo tang is a traditional herbal formula commonly used for the treatment of depression, but lack of scientific proof on its mechanism. It consisted of Glycyrrhiza uralensis Fisch. (licorice, Triticum aestivum L. (wheat and Zizphus jujuba Mill. (jujube. The objective of this study is to investigate the antidepressant effects of Gan-Mai-Dazao-Tang and its ingredients in rats exposed to forced swimming test (FST. The 72 of male Nerl: Wistar rats (8 weeks old were randomized into control (10 mL/kg bw H2O, licorice (0.4 g/kg bw, wheat (1.6 g/kg bw, jujube (0.5 g/kg bw, Gan-Mai-Da-Zao-Tang (2.5 g/kg bw of licorice: wheat: jujube in ratio of 5:20:6 and Prozac (18 mg/kg bw groups. Samples were administered by oral gavage for 21 days. FST was performed on 21st day, with 15 min for pretest followed by 5 min for real test. Then, the animals were sacrificed and brain tissues were collected for monoamines analyses. The Gan-Mai-Da-Zao-Tang (LWJ showed significantly down-regulation of immobility time, 3,4-dihydroxyphenylacetic acid (DOPAC and DOPAC/dopamine (DA turnover rates, and also enhanced the concentration of serotonin (5-HT and DA in brain tissues, as compared with the control. The LWJ stated the potent antidepressant-like effect by modulating these monoamines concentration, while the licorice, wheat and jujube did not reported significant results as compared with control group. The positive control (Prozac was noted with significantly reduction in body weight and appetite. In conclusion, the antidepressant-like effects of LWJ might be mediated by the regulation of monoamine neurotransmitters. Thus, it could beneficial in depression treatment as a complementary approach.

  12. Clinical doses of citalopram or reboxetine differentially modulate passive and active behaviors of female Wistar rats with high or low immobility time in the forced swimming test.

    Science.gov (United States)

    Flores-Serrano, Ana Gisela; Vila-Luna, María Leonor; Álvarez-Cervera, Fernando José; Heredia-López, Francisco José; Góngora-Alfaro, José Luis; Pineda, Juan Carlos

    2013-09-01

    The sensitivity of immobility time (IT) to antidepressant-drugs differs in rats expressing high or low motor activity during the forced swimming test (FST). However, whether this heterogeneity is expressed after the administration of the most selective serotonin and norepinephrine reuptake inhibitors (SSRIs and SNRIs, respectively) is unknown. We compared the influence of either the SSRI citalopram or the SNRI reboxetine with the tricyclic antidepressant amitriptyline on two subgroups of female Wistar rats expressing high IT (HI; at or above the mean value) or low IT (LI; below the mean) during the initial 5 min of the first session of the FST. None of the tested drugs increased motor activity in the open field test. When vehicle was applied to either HI or LI rats, IT increased in the second session of the FST. This increment concurred with a simultaneous climbing time (CT) decrement. When amitriptyline (15 mg/kg) was tested the CT increased for both HI and LI rats. This increment was accompanied by an IT decrement in HI and LI rats. Reboxetine (0.16 or 1 mg/kg) precluded IT and CT changes in both HI and LI rats and produced a swimming time reduction. Citalopram (0.4, 1, and 3 mg/kg) essentially mimicked the influence of reboxetine on the IT and CT in LI rats, as well as in HI rats, but in the latter case only at 3 mg/kg. Yet, at the dose of 10 mg/kg citalopram lacked this effect in both subgroups. No differences were detected when the IT of LI rats was evaluated with citalopram (3 mg/kg) during estrus or diestrus stage. These results show that clinical doses of citalopram produced an antidepressant-like effect selectively in LI rats, while amitriptyline or reboxetine produced this effect in both LI and HI animals. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Effects of forced swimming stress on thyroid function, pituitary thyroid-stimulating hormone and hypothalamus thyrotropin releasing hormone expression in adrenalectomy Wistar rats.

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    Sun, Qiuyan; Liu, Aihua; Ma, Yanan; Wang, Anyi; Guo, Xinhong; Teng, Weiping; Jiang, Yaqiu

    2016-11-01

    In order to study the impact that is imposed on the hypothalamic-pituitary-thyroid (HPT) axis of adrenalectomy male Wistar rats by stress caused by swimming, the blood level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH), the expression of TSHβ mRNA at the pituitary and thyrotropin releasing hormone (TRH) expression at the paraventricular nucleus (PVN) were measured. A total of 50 male Wistar rats of 6-8 weeks of age and with an average weight of 190-210 grams were randomly divided into the following two groups: The surgical (without adrenal glands) and non-surgical (adrenalectomy) group. These two groups were then divided into the following five groups, according to the time delay of sacrifice following forced swim (10 min, 2 h, 12 h and 24 h) and control (not subjected to swimming) groups. A bilateral adrenalectomy animal model was established. Serum TSH in the blood was measurement by chemiluminescent immunoassay, and cerebrum tissue were excised for the measurement of TRH expression using an immunohistochemistry assay. In addition, pituitaries were excised for the extraction of total RNA. Finally, reverse transcription-quantitative polymerase chain reaction was performed for quantitation of TSHβ. Following swimming, the serum T3, T4 and TSH, the TSHβ mRNA expression levels in the pituitary and the TRH expression in the PVN of the surgical group were gradually increased. In the non-surgical group, no significant differences were observed in the serum T3, T4 and TSH levels compared with the control group. The TSHβ mRNA expression at the pituitary showed a similar result. Furthermore, the TRH expression at PVN was gradually increased and stress from swimming could increase the blood T4, T3 and TSH levels, TSHβ mRNA expression at the pituitary and TRH expression at the PVN in adrenalectomy Wistar rats. Moreover, the index in the surgical group changed significantly compared with the non-surgical group. In conclusion, the results

  14. A medicinal herb, Melissa officinalis L. ameliorates depressive-like behavior of rats in the forced swimming test via regulating the serotonergic neurotransmitter.

    Science.gov (United States)

    Lin, Shih-Hang; Chou, Mei-Ling; Chen, Wei-Cheng; Lai, Yi-Syuan; Lu, Kuan-Hung; Hao, Cherng-Wei; Sheen, Lee-Yan

    2015-12-04

    Depression is a serious psychological disorder that causes extreme economic loss and social problems. However, the conventional medications typically cause side effects that result in patients opting to out of therapy. Lemon balm (Melissa officinalis L., MO) is an old and particularly reliable medicinal herb for relieving feelings of melancholy, depression and anxiety. The present study aims to investigate the antidepressant-like activity of water extract of MO (WMO) by evaluating its influence on the behaviors and the relevant neurotransmitters of rats performed to forced swimming test. Two phases of the experiment were conducted. In the acute model, rats were administered ultrapure water (control), fluoxetine, WMO, or the indicated active compound (rosmarinic acid, RA) three times in one day. In the sub-acute model, rats were respectively administered ultrapure water (control), fluoxetine, or three dosages of WMO once a day for 10 days. Locomotor activity and depression-like behavior were examined using the open field test and the forced swimming test, respectively. The levels of relevant neurotransmitters and their metabolites in the frontal cortex, amygdala, hippocampus, and striatum were analyzed by high performance liquid chromatography. In the acute model, WMO and RA significantly reduced depressive-like behavior but the type of related neurotransmitter could not be determined. The results indicated that the effect of WMO administration on the reduction of immobility time was associated with an increase in swimming time of the rats, indicative of serotonergic neurotransmission modulation. Chromatography data validated that the activity of WMO was associated with a reduction in the serotonin turnover rate. The present study shows the serotonergic antidepressant-like activity of WMO. Hence, WMO may offer a serotonergic antidepressant activity to prevent depression and to assist in conventional therapies. Copyright © 2015. Published by Elsevier Ireland Ltd.

  15. Stimulation of the metabotropic glutamate (mGlu) 2 receptor attenuates the MK-801-induced increase in the immobility time in the forced swimming test in rats.

    Science.gov (United States)

    Kawaura, Kazuaki; Karasawa, Jun-Ichi; Hikichi, Hirohiko

    2016-02-01

    Negative symptoms of schizophrenia are poorly managed using the currently available antipsychotics. Previous studies indicate that agonists of the metabotropic glutamate (mGlu) 2/3 receptors may provide a novel approach for the treatment of schizophrenia. However, the effects of mGlu2/3 receptor agonists or mGlu2 receptor positive allosteric modulators have not yet been clearly elucidated in animal models of the negative symptoms of schizophrenia. Recently, we reported that the forced swimming test in rats treated with subchronic MK-801, an NMDA receptor antagonist, may be regarded as a useful test to evaluate the activities of drugs against the negative symptoms of schizophrenia. We evaluated the effects of LY379268, an mGlu2/3 receptor agonist, and BINA, an mGlu2 receptor positive allosteric modulator, on the hyperlocomotion induced by acute administration of MK-801 (0.15mg/kg, sc) and on the increase in the immobility time in the forced swimming test induced by subchronic treatment with MK-801 (0.5mg/kg, sc, twice a day for 7 days) in rats. Both LY379268 (3mg/kg, sc) and BINA (100mg/kg, ip) attenuated the increase in the immobility time induced by subchronic treatment with MK-801 at the same doses at which they attenuated the MK-801-induced increase in locomotor activity, but had no effect on the immobility time in saline-treated rats. The present results suggest that stimulation of the mGlu2 receptor attenuates the increase in the immobility time in the forced swimming test elicited by subchronic administration of MK-801, and may be potentially useful for treatment of the negative symptoms of schizophrenia. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  16. Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

    Science.gov (United States)

    2010-01-01

    Background The bed nucleus of stria terminalis (BNST) is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl2) in rats subjected to the forced swimming test (FST). Methods Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest). Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test). Independent groups of rats received bilateral microinjections of CoCl2 (1 mM/100 nL) before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior. Results CoCl2 injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl2 was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test. Conclusion These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects. PMID:20515458

  17. Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

    Directory of Open Access Journals (Sweden)

    Joca Sâmia RL

    2010-06-01

    Full Text Available Abstract Background The bed nucleus of stria terminalis (BNST is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl2 in rats subjected to the forced swimming test (FST. Methods Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest. Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test. Independent groups of rats received bilateral microinjections of CoCl2 (1 mM/100 nL before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior. Results CoCl2 injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl2 was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test. Conclusion These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects.

  18. Immobility time during the forced swimming test predicts sensitivity to amitriptyline, whereas traveled distance in the circular corridor indicates resistance to treatment in female Wistar rats.

    Science.gov (United States)

    Flores-Serrano, Ana G; Zaldívar-Rae, Jaime; Salgado, Humberto; Pineda, Juan C

    2015-03-25

    Among the main issues in the pharmacological treatment of depression are the wide variation in response to antidepressants among individual patients and the lack of indexes that allow prediction of which drug will be effective in a particular case. We evaluated whether differential sensitivity to amitriptyline is related to dichotomous categorization of individuals on the basis of their behavioral responses to two common paradigms used to evaluate the potential of tricyclic drugs as antidepressants. Hence, we categorized a cohort of 38 female rats on the basis of their immobility time in the conditioning phase of the forced swimming test [FST; high immobility (HI) vs. low immobility (LI) rats] and their locomotor behavior in the circular corridor test [high locomotor response (HR) vs. low locomotor response (LR) rats]. We subjected the rodents to the FST while under the influence of vehicle (n=20) or amitriptyline (15 mg/kg; n=18). We found no statistical evidence of dependence between categorizations of rats on the basis of their behavior in the FST and circular corridor test. Rats categorized as HI/LI and HR/LR significantly differed in their sensitivity/resistance to amitriptyline, as evidenced by changes (or lack thereof) in their immobility time, climbing time, and swimming time during the FST. These results confirm that different behavioral styles among rats are linked to differential sensitivity/resistance to antidepressants. However, we specifically found that categorizing rats as HI/LI better reflected sensitivity to amitriptyline, whereas categorizing them as HR/LR better revealed resistance to the drug. These differential responses should be considered in experimental approaches. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

  19. Effect of co-treatment with fluoxetine or mirtazapine and risperidone on the active behaviors and plasma corticosterone concentration in rats subjected to the forced swim test.

    Science.gov (United States)

    Rogóż, Zofia; Kabziński, Marcin; Sadaj, Witold; Rachwalska, Paulina; Gądek-Michalska, Anna

    2012-01-01

    Several clinical reports have postulated a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants in treatment-resistant depression. The present study aimed to examine the effect of treatment with fluoxetine or mirtazapine, given separately or jointly with risperidone, on active behavior and plasma corticosterone level in male Wistar rats subjected to the forced swim test (FST). The obtained results showed that fluoxetine (5 mg/kg), mirtazapine (5 and 10 mg/kg) or risperidone (0.05 and 0.1 mg/kg) did not change the active behavior of rats in the FST. However, co-treatment with fluoxetine (10 mg/kg) and risperidone (0.1 mg/kg) induced an antidepressant-like effect in that test because it significantly increased the swimming time and decreased the immobility time, while combined treatment with mirtazapine at 5 and 10 mg/kg and risperidone at 0.05 and 0.1 mg/kg evoked a significant increase in the swimming time and also climbing, and decreased the immobility time. WAY 100635 (a 5-HT(1A) receptor antagonist) at a dose of 0.1 mg/kg inhibited the antidepressant-like effect induced by co-administration of fluoxetine or mirtazapine and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined treatment with fluoxetine or mirtazapine and risperidone failed to enhance the exploratory activity of rats. Co-treatment with fluoxetine or mirtazapine and risperidone did not reduce the stress-induced increase in plasma corticosterone concentration in animals subjected to the FST. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of fluoxetine and mirtazapine in the FST (but does not normalize the stress-induced increase in corticosterone level in these rats), and that 5-HT(1A) receptors may play some role in these effects.

  20. Mechanism of synergistic action following co-treatment with pramipexole and fluoxetine or sertraline in the forced swimming test in rats.

    Science.gov (United States)

    Rogóz, Zofia; Skuza, Grazyna

    2006-01-01

    The aim of the present study was to examine the effect of combined treatment of male Wistar rats with pramipexole and fluoxetine or sertraline in the forced swimming test. The obtained results showed that co-treatment with pramipexole (0.1 mg/kg) and fluoxetine (10 mg/kg) or sertraline (5 mg/kg) (in doses inactive per se) exhibited antidepressant-like activity in the forced swimming test. Sulpiride (a dopamine D(2/3) receptor antagonist) and WAY 100635 (a 5-HT(1A) receptor antagonist), either being ineffective in the forced swimming test, inhibited the antidepressant-like effect induced by co-administration of pramipexole and fluoxetine or sertraline. However, SCH 23390 (a dopamine D(1) receptor antagonist) only partly did not alter the effect of pramipexole given jointly with antidepressant drugs; on the other hand, S 33084 (a dopamine D(3) receptor antagonist) only partly decreased (in a statistically insignificant manner) that effect. Moreover, progesterone and BD 1047 (a sigma(1) receptor antagonist) counteracted the antidepressant-like effect induced by co-administration of pramipexole and sertraline (but not pramipexole and fluoxetine). In that test, active behavior did not reflect the increases in general activity, since combined administration of pramipexole and fluoxetine or sertraline failed to enhance the locomotor activity of rats. None of the tested drugs (SCH 23390, sulpiride, S 33084, WAY 100635, BD 1047 and progesterone) - alone or in combination with pramipexole and fluoxetine or sertraline - changed locomotor activity. The results described in the present paper indicate that co-administration of pramipexole and fluoxetine or sertraline may induce a more pronounced antidepressive activity than does treatment with pramipexole alone, and that in addition to other mechanisms, dopamine D(2/3) and 5-HT(1A) receptors may contribute to the antidepressant-like activity of pramipexole and fluoxetine or sertraline in the forced swimming test in rats

  1. Flavonoid-rich fraction of the Monodora tenuifolia seed extract attenuates behavioural alterations and oxidative damage in forced-swim stressed rats.

    Science.gov (United States)

    Ekeanyanwu, Raphael Chukwuma; Njoku, Obioma Uzoma

    2015-03-01

    The antidepressant effects of the flavonoid-rich fraction of Monodora tenuifolia seed extract were examined by assessing the extent of attenuation of behavioural alterations and oxidative damage in the rats that were stressed by forced swim test. Compared with the model control group, the altered behavioural parameters were attenuated significantly (P fluoxetine (10 mg·kg(-1)). The flavonoid-rich fraction and fluoxetine improved significantly (P < 0.05) the activities of the antioxidant enzymes such as superoxide dismutase and catalase as well as other biochemical parameters such as reduced glutathione, protein, and nitrite in the brain of the stressed rats. These results suggested that the flavonoid-rich fraction of Monodora tenuifolia seed extract exerted the antidepressant-like effects which could be useful in the management of stress induced disease. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  2. Anti-anxiety activity of successive extracts of Angelica archangelica Linn. on the elevated T-maze and forced swimming tests in rats.

    Science.gov (United States)

    Kumar, Dinesh; Bhat, Zulfiqar Ali; Shah, M Y

    2012-09-01

    Angelica archangelica Linn. is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety. We evaluated the anxiolytic effect of successive extracts of A. archangelica linn. (SAE) on rats tested in the elevated T-maze test (an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans. A. archangelica (1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether (40-60 degrees C), chloroform, ethyl acetate, methanol and decoction with water] in order of increasing polarity (yield: 6.9%, 7.3%, 5.1%, 11.88% and 8.2% w/w, respectively). SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats. Oral dosing of diazepam (1 mg/kg) and extracts (50, 100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test: it increased one-way escape and decreased inhibitory avoidance on the first, third and seventh day. In the forced swimming test, imipramine and SAE showed antidepressant- and anxiolytic-like effects as reflected by increased climbing time, swimming time and decreased immobility time on the first, third and seventh day. Aqueous and methanol extracts showed the most, petroleum ether (40-60 degrees C) and chloroform intermediate, and ethyl acetate the least anxiolytic activity (*P<0.05, **P<0.01, ***P< 0.001) in both models. These results suggest the anti-anxiety activity of various extracts of A. archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.

  3. A role for serotonin in the antidepressant activity of NG-Nitro-L-arginine, in the rat forced swimming test.

    Science.gov (United States)

    Gigliucci, Valentina; Buckley, Kathleen Niamh; Nunan, John; O'Shea, Karen; Harkin, Andrew

    2010-02-01

    The present study determined regional serotonin (5-HT) synthesis and metabolism changes associated with the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine (L-NA) and the influence of 5-HT receptor blockade in the antidepressant-like actions of L-NA in the forced swimming test (FST). Regional effects of L-NA (5,10 and 20mg/kg i.p.) on tryptophan hydroxylase (TPH) activity, the rate limiting enzyme for 5-HT synthesis, were determined by measuring accumulation of the transient intermediate 5-hydoxytryptophan (5-HTP) following in vivo administration of the amino acid decarboxylase inhibitor, NSD 1015 (100mg/kg). L-NA (5-20mg/kg) dose dependently increased 5-HTP accumulation, particularly in the amygdaloid cortex, following exposure to the FST. L-NA also provoked an increase in regional brain 5-HIAA concentrations and in the 5-HIAA:5-HT metabolism ratio. Co-treatment with NSD-1015 failed to consistently modify the antidepressant-like effects of L-NA in the FST. Sub-active doses of L-NA (1mg/kg) and the 5-HT re-uptake inhibitor fluoxetine (2.5mg/kg) acted synergistically to increase swimming in the test. Co-treatment with the non-selective 5-HT receptor antagonist metergoline (1, 2 and 4mg/kg), attenuated the L-NA (20mg/kg)-induced reduction in immobility and increase in swimming behaviours. Metergoline alone however provoked an increase in immobility and reduction in swimming behaviours in the test. A similar response was obtained following co-treatment with the preferential 5-HT(2A) receptor antagonist ketanserin (5mg/kg) and the 5-HT(2C) receptor antagonist RO-430440 (5mg/kg). Co-treatment with the 5-HT(1A) receptor antagonist WAY 100635 (0.3mg/kg) or the 5-HT(1B) receptor antagonist GR 127935 (4mg/kg) failed to influence the antidepressant-like activity of L-NA. Taken together these data provide further support for a role for 5-HT in the antidepressant-like properties of NOS inhibitors. Copyright 2009 Elsevier Inc. All rights reserved.

  4. Fluoxetine increases the activity of the ERK-CREB signal system and alleviates the depressive-like behavior in rats exposed to chronic forced swim stress.

    Science.gov (United States)

    Qi, Xiaoli; Lin, Wenjuan; Li, Junfa; Li, Huanhuan; Wang, Weiwen; Wang, Donglin; Sun, Meng

    2008-08-01

    Our previous research indicates that the extracellular signal-regulated kinase (ERK)-cyclic AMP-responsive-element-binding protein (CREB) signal system may be involved in the molecular mechanism of depression. The present study further investigated the effect of antidepressant fluoxetine on the ERK-CREB signal system and the depressive-like behaviors in rats. Fluoxetine was administrated to either naive rats or stressed rats for 21 days. The results showed that chronic forced swim stress induced depressive-like behaviors and decreased the levels of P-ERK2, P-CREB, ERK1/2 and CREB in hippocampus and prefrontal cortex. Fluoxetine alleviated the depressive-like behaviors and reversed the disruptions of the P-ERK2 and P-CREB in stressed rats. Fluoxetine also exerted mood-elevating effect and increased the levels of the P-ERK2 and P-CREB in naive rats. These results suggest that the ERK-CREB signal system may be the targets of the antidepressant action of fluoxetine and participate in the neuronal mechanism of depression.

  5. Effects of a glycine transporter-1 inhibitor and D-serine on MK-801-induced immobility in the forced swimming test in rats.

    Science.gov (United States)

    Kawaura, Kazuaki; Koike, Hiroyuki; Kinoshita, Kohnosuke; Kambe, Daiji; Kaku, Ayaka; Karasawa, Jun-ichi; Chaki, Shigeyuki; Hikichi, Hirohiko

    2015-02-01

    Glutamatergic dysfunction, particularly the hypofunction of N-methyl-D-aspartate (NMDA) receptors, is involved in the pathophysiology of schizophrenia. The positive modulation of the glycine site on the NMDA receptor has been proposed as a novel therapeutic approach for schizophrenia. However, its efficacy against negative symptoms, which are poorly managed by current medications, has not been fully addressed. In the present study, the effects of the positive modulation of the glycine site on the NMDA receptor were investigated in an animal model of negative symptoms of schizophrenia. The subchronic administration of MK-801 increased immobility in the forced swimming test in rats without affecting spontaneous locomotor activity. The increased immobility induced by MK-801 was attenuated by the atypical antipsychotic clozapine but not by either the typical antipsychotic haloperidol or the antidepressant imipramine, indicating that the increased immobility induced by subchronic treatment with MK-801 in the forced swimming test may represent a negative symptom of schizophrenia. Likewise, positive modulation of the glycine sites on the NMDA receptor using an agonist for the glycine site, D-serine, and a glycine transporter-1 inhibitor, N-[(3R)-3-([1,1'-biphenyl]-4-yloxy)-3-(4-fluorophenyl)propyl]-N-methylglycine hydrochloride (NFPS), significantly reversed the increase in immobility in MK-801-treated rats without reducing the immobility time in vehicle-treated rats. The present results show that the stimulation of the NMDA receptor through the glycine site on the receptor either directly with D-serine or by blocking glycine transporter-1 attenuates the immobility elicited by the subchronic administration of MK-801 and may be potentially useful for the treatment of negative symptoms of schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Further evidence for conditioned taste aversion induced by forced swimming.

    Science.gov (United States)

    Masaki, Takahisa; Nakajima, Sadahiko

    2005-01-31

    A series of experiments with rats reported that aversion to a taste solution can be established by forced swimming in a water pool. Experiment 1 demonstrated that correlation of taste and swimming is a critical factor for this phenomenon, indicating associative (i.e., Pavlovian) nature of this learning. Experiment 2 showed that this learning obeys the Pavlovian law of strength, by displaying a positive relationship between the duration of water immersion in training and the taste aversion observed in subsequent testing. Experiment 3 revealed that swimming rather than being wet is the critical agent, because a water shower did not endow rats with taste aversion. Experiment 4 found that taste aversion was a positive function of water level of the pools in training (0, 12 or 32 cm). These results, taken together, suggest that energy expenditure caused by physical exercise might be involved in the development of taste aversion.

  7. Fluoxetine, 17-β estradiol or folic acid combined with intra-lateral septal infusions of neuropeptide Y produced antidepressant-like actions in ovariectomized rats forced to swim.

    Science.gov (United States)

    Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia

    2011-12-01

    Folic acid is antidepressant, either alone or combined with several antidepressant drugs. However, the antidepressant-like actions of folic acid combined with intra-lateral septal (LSN) infusions of neuropeptide Y (NPY) in the forced swimming test (FST) have not been tested before. Thus, systemic injections of fluoxetine (20.0mg/kg, Pfluoxetine (15.0 mg/kg, P<0.05; s.c.) combined with subthreshold doses of NPY (2.5 μg/rat, P<0.05; intra-LSN) and these combinations produced antidepressant-like actions; which were canceled by BIBP 3226 (a NPY-Y1 receptor antagonist). It is concluded that folic acid produced antidepressant-like effects probably through the participation of the NPY Y1 receptors found in the lateral septal nuclei. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Water spray-induced grooming is negatively correlated with depressive behavior in the forced swimming test in rats.

    Science.gov (United States)

    Shiota, Noboru; Narikiyo, Kimiya; Masuda, Akira; Aou, Shuji

    2016-05-01

    Rodents show grooming, a typical self-care behavior, under stress and non-stress conditions. Previous studies revealed that grooming under stress conditions such as the open-field test (OFT) or the elevated plus-maze test (EPM) is associated with anxiety, but the roles of grooming under non-stress conditions are not well understood. Here, we examined spray-induced grooming as a model of grooming under a non-stress condition to investigate the relationship between this grooming and depression-like behavior in the forced swim test (FST) and tail suspension test, and we compared spray-induced grooming with OFT- and EPM-induced grooming. The main finding was that the duration of spray-induced grooming, but not that of OFT/EPM-induced grooming, was negatively correlated with the duration of immobility in the FST, an index of depression-like behavior. The results suggest that spray-induced grooming is functionally different from the grooming in the OFT and EPM and is related to reduction of depressive behavior.

  9. Effects of fluoxetine on the rat brain in the forced swimming test: a [F-18]FDG micro-PET imaging study.

    Science.gov (United States)

    Jang, Dong-Pyo; Lee, So-Hee; Park, Chan-Woong; Lee, Sang-Yoon; Kim, Young-Bo; Cho, Zang-Hee

    2009-02-13

    We used the [F-18]FDG micro-PET neuroimaging to examine the effects of fluoxetine on brain activity in rats and on their behavioral response in the forced swimming test (FST). In the first experiment, the rats were administered doses of fluoxetine (10 or 20mg/kg) 24, 19 and 1h before the rat brains were scanned. Fluoxetine induced strong activation of the dorsal hippocampus and the deactivation of the inferior colliculus, medulla oblongata, and prelimbic cortex in a dose-dependent manner. These results seemed to be related with the changes in 5-HT (5-hydroxytryptamine, serotonin) levels after selective serotonin reuptake-inhibitor treatments. In the second experiment, the changes in glucose metabolism in the test session were measured after fluoxetine was given between pre-test and test sessions of the FST. Fluoxetine administration significantly decreased immobility behavior compared with saline administration. At the same time, the activity of the insular/piriform cortex decreased significantly. In contrast, the extent of cerebellar activation increased. The glucose metabolism of the dorsal hippocampus also increased, which suggests that post-stress changes in the facilitation of hippocampal serotonergic neurotransmission lead to decreased immobilization in the FST.

  10. Antidepressant-like effects of the ethyl acetate soluble fraction of the root bark of Morus alba on the immobility behavior of rats in the forced swim test.

    Science.gov (United States)

    Lim, Dong Wook; Kim, Yun Tai; Park, Ji-Hae; Baek, Nam-In; Han, Daeseok

    2014-06-12

    In this study, the antidepressant-like effects of Morus alba fractions in rats were investigated in the forced swim test (FST). Male Wistar rats (9-week-old) were administered orally the M. alba ethyl acetate (EtOAc 30 and 100 mg/kg) and M. alba n-butanol fractions (n-BuOH 30 and 100 mg/kg) every day for 7 consecutive days. On day 7, 1 h after the final administration of the fractions, the rats were exposed to the FST. M. alba EtOAc fraction at the dose of 100 mg/kg induced a decrease in immobility behavior (p alba EtOAc fraction at the dose of 100 mg/kg decreased the hypothalamic-pituitary-adrenal (HPA) axis response to the stress, as indicated by an attenuated corticosterone response and decreased c-fos immunoreactivity in the hippocampal and hypothalamic paraventricular nucleus (PVN) region. These findings demonstrated that M. alba EtOAc fraction have beneficial effects on depressive behaviors and restore both altered c-fos expression and HPA activity.

  11. Effects of Forced Swimming Stress on ERK and Histone H3 Phosphorylation in Limbic Areas of Roman High- and Low-Avoidance Rats.

    Science.gov (United States)

    Morello, Noemi; Plicato, Ornella; Piludu, Maria Antonietta; Poddighe, Laura; Serra, Maria Pina; Quartu, Marina; Corda, Maria Giuseppa; Giorgi, Osvaldo; Giustetto, Maurizio

    2017-01-01

    Stressful events evoke molecular adaptations of neural circuits through chromatin remodeling and regulation of gene expression. However, the identity of the molecular pathways activated by stress in experimental models of depression is not fully understood. We investigated the effect of acute forced swimming (FS) on the phosphorylation of the extracellular signal-regulated kinase (ERK)1/2 (pERK) and histone H3 (pH3) in limbic brain areas of genetic models of vulnerability (RLA, Roman low-avoidance rats) and resistance (RHA, Roman high-avoidance rats) to stress-induced depression-like behavior. We demonstrate that FS markedly increased the density of pERK-positive neurons in the infralimbic (ILCx) and the prelimbic area (PrLCx) of the prefrontal cortex (PFCx), the nucleus accumbens, and the dorsal blade of the hippocampal dentate gyrus to the same extent in RLA and RHA rats. In addition, FS induced a significant increase in the intensity of pERK immunoreactivity (IR) in neurons of the PFCx in both rat lines. However, RHA rats showed stronger pERK-IR than RLA rats in the ILCx both under basal and stressed conditions. Moreover, the density of pH3-positive neurons was equally increased by FS in the PFCx of both rat lines. Interestingly, pH3-IR was higher in RHA than RLA rats in PrLCx and ILCx, either under basal conditions or upon FS. Finally, colocalization analysis showed that in the PFCx of both rat lines, almost all pERK-positive cells express pH3, whereas only 50% of the pH3-positive neurons is also pERK-positive. Moreover, FS increased the percentage of neurons that express exclusively pH3, but reduced the percentage of cells expressing exclusively pERK. These results suggest that (i) the distinctive patterns of FS-induced ERK and H3 phosphorylation in the PFCx of RHA and RLA rats may represent molecular signatures of the behavioural traits that distinguish the two lines and (ii) FS-induced H3 phosphorylation is, at least in part, ERK-independent.

  12. Omega-3 fatty acid deficiency does not alter the effects of chronic fluoxetine treatment on central serotonin turnover or behavior in the forced swim test in female rats.

    Science.gov (United States)

    McNamara, Robert K; Able, Jessica A; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; Lipton, Jack W

    2013-12-01

    While translational evidence suggests that long-chain omega-3 fatty acid status is positively associated with the efficacy of selective serotonin reuptake inhibitor drugs, the neurochemical mechanisms mediating this interaction are not known. Here, we investigated the effects of dietary omega-3 (n-3) fatty acid insufficiency on the neurochemical and behavioral effects of chronic fluoxetine (FLX) treatment. Female rats were fed diets with (CON, n=56) or without (DEF, n=40) the n-3 fatty acids during peri-adolescent development (P21-P90), and one half of each group was administered FLX (10mg/kg/day) for 30days (P60-P90) prior to testing. In adulthood (P90), regional brain serotonin (5-HT) and 5-hydroxyindoleacetic (5-HIAA) concentrations, presynaptic markers of 5-HT neurotransmission, behavioral responses in the forced swim test (FST), and plasma FLX and norfluoxetine (NFLX) concentrations were investigated. Peri-adolescent n-3 insufficiency led to significant reductions in cortical docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (-25%, p≤0.0001) and DEF+FLX (-28%, p≤0.0001) rats. Untreated DEF rats exhibited significantly lower regional 5-HIAA/5-HT ratios compared with untreated CON rats, but exhibited similar behavioral responses in the FST. In both CON and DEF rats, chronic FLX treatment similarly and significantly decreased 5-HIAA concentrations and the 5-HIAA/5-HT ratio in the hypothalamus, hippocampus, and nucleus accumbens, brainstem tryptophan hydroxylase-2 mRNA expression, and immobility in the FST. While the FLX-induced reduction in 5-HIAA concentrations in the prefrontal cortex was significantly blunted in DEF rats, the reduction in the 5-HIAA/5-HT ratio was similar to CON rats. Although plasma FLX and NFLX levels were not significantly different in DEF and CON rats, the NFLX/FLX ratio was significantly lower in DEF+FLX rats. These preclinical data demonstrate that n-3 fatty acid deficiency does not significantly reduce the effects of chronic

  13. Modulatory effect of cilostazol on tramadol-induced behavioral and neurochemical alterations in rats challenged across the forced swim despair test

    Directory of Open Access Journals (Sweden)

    Noha M. Gamil

    2016-06-01

    Full Text Available Pain-associated depression is encountered clinically in some cases such as cancer, chronic neuropathy, and after operations. Tramadol is an opioid analgesic drug that may modulate monoaminergic neurotransmission by inhibition of noradrenaline and serotonin reuptake that may contribute to its antidepressant-like effects. Clinically, tramadol is used either alone or in combination with other NSAIDs in the treatment of cases associated with pain and depression, e.g. low back pain, spinal cord injury, and post-operative pain management. However, tramadol monotherapy as an antidepressant is impeded by severe adverse effects including seizures and serotonin syndrome. Interestingly, phosphodiesterase-III inhibitors demonstrated novel promising antidepressant effects. Among which, cilostazol was reported to attenuate depression in post-stroke cases, geriatrics and patients undergoing carotid artery stenting. Therefore, this study was carried out to investigate the possible antidepressant-like effects of tramadol and/or cilostazol on the behavioral level in experimental animals, and to examine the neurochemical and biochemical effects of tramadol, cilostazol and their combination in rats, in order to explore the probable mechanisms of action underlying their effects. To achieve our target, male albino mice and rats were randomly allocated into five groups and administered either vehicle for control, fluoxetine (20 mg/kg, p.o., tramadol HCl (20 mg/kg, p.o., cilostazol (100 mg/kg, p.o., or combination of both tramadol and cilostazol. At day 14, mice and rats were challenged in the tail suspension test and forced swim test, respectively. Rats were sacrificed and brains were isolated for determination of brain monoamines, MDA, NO, SOD, and TNF-α. The current results showed that concurrent administration of cilostazol to tramadol-treated animals modulated depression on the behavioral level, and showed ameliorative neurochemical and biochemical effects

  14. Participation of hippocampal nitric oxide synthase and soluble guanylate cyclase in the modulation of behavioral responses elicited by the rat forced swimming test.

    Science.gov (United States)

    Sales, Amanda J; Hiroaki-Sato, Vinícius A; Joca, Sâmia R L

    2017-02-01

    Systemic or hippocampal administration of nitric oxide (NO) synthase inhibitors induces antidepressant-like effects in animals, implicating increased hippocampal levels of NO in the neurobiology of depression. However, the role played by different NO synthase in this process has not been clearly defined. As stress is able to induce neuroinflammatory mechanisms and trigger the expression of inducible nitric oxide synthase (iNOS) in the brain, as well as upregulate neuronal nitric oxide synthase (nNOS) activity, the aim of the present study was to investigate the possible differential contribution of hippocampal iNOS and nNOS in the modulation of the consequences of stress elicited by the forced swimming test. Male Wistar rats received intrahippocampal injections, immediately after the pretest or 1 h before the forced swimming test, of selective inhibitors of nNOS (N-propyl-L-arginine), iNOS (1400W), or sGC (ODQ), the main pharmacological target for NO. Stress exposure increased nNOS and phospho-nNOS levels at all time points, whereas iNOS expression was increased only 24 h after the pretest. All drugs induced an antidepressant-like effect. However, whereas the nNOS inhibitor was equally effective when injected at different times, the iNOS inhibitor was more effective 24 h after the pretest. These results suggest that hippocampal nNOS and iNOS contribute to increase in NO levels in response to stress, although with a differential time course after stress exposure.

  15. Age-related changes in the antidepressant-like effect of desipramine and fluoxetine in the rat forced-swim test.

    Science.gov (United States)

    Olivares-Nazario, Maribel; Fernández-Guasti, Alonso; Martínez-Mota, Lucía

    2016-02-01

    Some reports suggest that older patients are less responsive to antidepressants than young adults, but this idea has not been fully supported. Here, we investigated the role of aging in the behavioral effects of the antidepressants, desipramine (DMI) (5, 10, and 20 mg/kg) and fluoxetine (FLX) (5, 10, and 20 mg/kg) in young adults (3-5 months), middle-aged (MA, 12-15 months), and senescent (SE, 23-25 months) male rats in the forced-swim test. In addition, locomotor activity and motor coordination were assessed as side-effects. DMI and fluoxetine produced an antidepressant-like effect in YA and MA animals, although in the latter group, a shift to the right in the dose-response curve was found for DMI. Importantly, neither drug was effective in SE animals. Motor side-effects were produced mainly by DMI in MA and SE rats. Therefore, a decrease in the antidepressant-like effect is associated strongly with senescence as well as an increased vulnerability to motor side-effects, particularly of tricyclics. This study is significant because SE animals are scarcely studied in pharmacological screening tests, and our findings might be useful for improving antidepressant treatments for the increasing aged population.

  16. Neuronal NOS inhibitor 1-(2-trifluoromethylphenyl)-imidazole augment the effects of antidepressants acting via serotonergic system in the forced swimming test in rats.

    Science.gov (United States)

    Ulak, Güner; Mutlu, Oguz; Akar, Füruzan Yildiz; Komsuoğlu, F Ipek; Tanyeri, Pelin; Erden, B Faruk

    2008-10-01

    Treatment-resistant depression has necessitated new therapeutic strategies in augmenting the therapeutic actions of currently existing antidepressant drugs. The aim of this study was to investigate the possibility of synergistic interaction between 1-(2-trifluoromethylphenyl)-imidazole (TRIM), a novel neuronal nitric oxide synthase (nNOS) inhibitor and conventional antidepressants of different classes in the forced swimming test (FST) in rats. TRIM decreased the immobility time at 50 mg/kg doses in the FST in rats. Treatment with a behaviourally subeffective dose of TRIM (20 mg/kg) augmented the behavioural effect of tricyclic antidepressant imipramine, selective serotonin re-uptake inhibitor (SSRI) citalopram and fluoxetine or selective serotonin reuptake enhancer tianeptine but failed to augment the antidepressant effect of reboxetine, a noradrenaline re-uptake inhibitor, in this test. Therefore inhibition of NOS augments the effects of antidepressants acting on serotonergic system in the FST. Neither TRIM (10-50 mg/kg) nor other drug treatments affected the locomotor activity of animals. These findings are in agreement with the view that antidepressant effects or augmentation of these effects in the FST may be explained with inhibition of NOS activity and this may be a new approach in offering greater therapeutic efficacy of antidepressants acting via serotonergic system.

  17. Behavioral, neuroendocrine and neurochemical effects of the imidazoline I2 receptor selective ligand BU224 in naive rats and rats exposed to the stress of the forced swim test.

    Science.gov (United States)

    Finn, David P; Martí, Octavi; Harbuz, Michael S; Vallès, Astrid; Belda, Xavier; Márquez, Cristina; Jessop, David S; Lalies, Margaret D; Armario, Antonio; Nutt, David J; Hudson, Alan L

    2003-05-01

    There is evidence for alterations in imidazoline(2) (I(2)) receptor density in depressed patients. Selective I(2) receptor ligands modulate central monoamine levels and activate the hypothalamo-pituitary-adrenal (HPA) axis and may have potential as antidepressants. To study the behavioral effects of the selective I(2) receptor ligand BU224 in the rat forced swim test (FST) and its effects on the HPA axis and central monoaminergic responses. Rats received saline or BU224 (10 mg/kg IP) 24, 18 and 1 h prior to 15 min exposure to the FST. Saline- and BU224-treated non-stressed groups were included. Time spent immobile, struggling and swimming calmly was measured. Plasma adrenocorticotrophic hormone (ACTH) and corticosterone levels 90 min post-BU224 were measured in addition to tissue levels of monoamines and metabolites in the frontal cortex, hippocampus and hypothalamus. Administration of BU224 significantly reduced immobility and increased mild swimming without affecting struggling. Exposure to the FST significantly increased plasma ACTH and corticosterone levels. BU224 administration also increased ACTH and potentiated the ACTH response to FST with no effect on corticosterone. BU224 administration significantly increased frontal cortex 5-hydroxytryptamine (5-HT) levels and decreased 5-HT turnover in the frontal cortex and hypothalamus of rats exposed to FST. In non-stressed rats, BU224 decreased 5-HT turnover in the hippocampus and hypothalamus and decreased norepinephrine turnover in the frontal cortex. The selective I(2) receptor ligand BU224 reduces immobility of rats in the FST, indicative of antidepressant-like activity. This effect is accompanied by alterations in HPA axis and central monoaminergic activity.

  18. Inhibition of the L-arginine-nitric oxide pathway mediates the antidepressant effects of ketamine in rats in the forced swimming test.

    Science.gov (United States)

    Zhang, Guang-Fen; Wang, Nan; Shi, Jin-Yun; Xu, Shi-Xia; Li, Xiao-Min; Ji, Mu-Huo; Zuo, Zhi-Yi; Zhou, Zhi-Qiang; Yang, Jian-Jun

    2013-09-01

    Converging evidence shows that the acute administration of a sub-anaesthetic dose ketamine produces fast-acting and robust antidepressant properties in patients suffering from major depressive disorder. However, the underlying mechanisms have not been fully elucidated. The present study aimed to investigate the role of the L-arginine-nitric oxide pathway in the antidepressant effects of ketamine in rats performing the forced swimming test (FST). Ketamine (10 mg/kg) significantly decreased immobility times in the FST and the activities of total nitric oxide synthases (T-NOS), inducible NOS (iNOS), and endothelial NOS (eNOS) in the rat hippocampus. Interestingly, the plasma activities of T-NOS, iNOS, and eNOS increased after administration of ketamine. Furthermore, the activities of neuronal NOS (nNOS) did not change significantly in either the hippocampus or plasma after ketamine administration. The antidepressant effects of ketamine were prevented by pre-treatment with l-arginine (750 mg/kg). Pre-treatment with the NOS inhibitor L-NG-nitroarginine methyl ester at a sub-antidepressant dose of 50 mg/kg and ketamine at a sub-antidepressant dose of 3 mg/kg reduced immobility time in the FST compared to treatment with either drug alone. None of the drugs affected crossing and rearing scores in the open field test. These results suggest that the L-arginine-nitric oxide pathway is involved in the antidepressant effects of ketamine observed in rats in the FST and this involvement is characterised by the inhibition of brain T-NOS, iNOS, and eNOS activities. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. The Post-Ovariectomy Interval Affects the Antidepressant-Like Action of Citalopram Combined with Ethynyl-Estradiol in the Forced Swim Test in Middle Aged Rats

    Directory of Open Access Journals (Sweden)

    Nelly M. Vega Rivera

    2016-05-01

    Full Text Available The use of a combined therapy with low doses of estrogens plus antidepressants to treat depression associated to perimenopause could be advantageous. However the use of these combinations is controversial due to several factors, including the time of intervention in relation to menopause onset. This paper analyzes whether time post-OVX influences the antidepressant-like action of a combination of ethynyl-estradiol (EE2 and citalopram (CIT in the forced swim test (FST. Middle-aged (15 months old female Wistar rats were ovariectomized and after one or three weeks treated with EE2 (1.25, 2.5 or 5.0 µg/rat, s.c.; −48 h or CIT (1.25, 2.5, 5.0 or 10 mg/kg, i.p./3 injections in 24 h and tested in the FST. In a second experiment, after one or three weeks of OVX, rats received a combination of an ineffective dose of EE2 (1.25 µg/rat, s.c., −48 h plus CIT (2.5 mg/kg, i.p./3 injections in 24 h and subjected to the FST. Finally, the uteri were removed and weighted to obtain an index of the peripheral effects of EE2 administration. EE2 (2.5 or 5.0 µg/rat reduced immobility after one but not three weeks of OVX. In contrast, no CIT dose reduced immobility at one or three weeks after OVX. When EE2 (1.25 µg/rat was combined with CIT (2.5 mg/kg an antidepressant-like effect was observed at one but not three weeks post-OVX. The weight of the uteri augmented when EE2 was administrated three weeks after OVX. The data suggest that the time post-OVX is a crucial factor that contributes to observe the antidepressant-like effect of EE2 alone or in combination with CIT.

  20. Effects of co-administration of fluoxetine and risperidone on properties of peritoneal and pleural macrophages in rats subjected to the forced swimming test.

    Science.gov (United States)

    Roman, Adam; Kuśmierczyk, Justyna; Klimek, Ewa; Rogóż, Zofia; Nalepa, Irena

    2012-01-01

    Literature data show that administration of atypical antipsychotic drug, risperidone (RIS), enhances antidepressive action of fluoxetine (FLU). As antidepressive treatments also regulate immune functions, we examined whether combined administration of FLU and RIS to rats subsequently subjected to a forced swimming test (FST) modifies parameters of macrophage activity that are directly related to their immunomodulatory functions, i.e., arginase (ARG) activity and nitric oxide (NO) synthesis. Antidepressive action of the drugs was assessed with FST. Peritoneal and pleural cells were eluted and selected parameters of immunoreactivity were assessed colorimetrically. We found that the concomitant administration of FLU (10 mg/kg) and RIS (0.1 mg/kg) produced antidepressive-like effects in the FST,whereas the drugs were ineffective if administered separately. Stress related to the FST affected immune cell redistribution and changed some of the metabolic and immunomodulatory properties of macrophages. FLU administered to rats at a suboptimal dose for antidepressive action potently influenced macrophage immunomodulatory properties and redirected their activity toward anti-inflammatory M2 functional phenotype, as manifested by changes in the ARG/NO ratio. These effects resulted from a direct cellular influence of the drug, as well as its action via neuroendocrine pathways, as evidenced in peritoneal and pleural cells. Addition of RIS did not augment immunomodulatory action of FLU, though the combination showed antidepressant-like activity in the FST. Our results suggest that when the drugs were administered together, FLU was potent enough to redirect macrophages toward M2 activity. It is also postulated that drug-induced changes in the immune system are not so closely related to antidepressant-like effects or might be secondary to those produced in the neuroendocrine system.

  1. Antidepressant-like effects of the acute and chronic administration of nicotine in the rat forced swimming test and its interaction with fluoxetine [correction of flouxetine].

    Science.gov (United States)

    Vázquez-Palacios, G; Bonilla-Jaime, H; Velázquez-Moctezuma, J

    2004-05-01

    An antidepressant action of nicotine (NIC) has recently been suggested. Flouxetine, a selective serotonin reuptake inhibitor, is currently the most widely used antidepressant. In the present study, we analyzed the effects of the administration of NIC, fluoxetine (FLX), and the combination of both drugs given acutely, subchronically, and chronically as well as 7 days after chronic administration of these drugs on the forced swim test. Results showed that NIC induced a significant reduction of the time in immobility during the forced swim test (antidepressant effect), with a concomitant increase in swimming activity (serotonergic activation), after acute administration. These effects remain the same after subchronic and chronic administration. FLX failed to induce any effect after acute administration but did induce a significant decrease of immobility and an increase of swimming after subchronic administration. The effect of the chronic administration was significantly larger compared to subchronic administration. The combination of both drugs induced a larger effect than that observed after a single administration but only after subchronic treatment. No effect was observed after the end of the 7-day treatments. Data suggest that NIC has an antidepressant action that is expressed faster than FLX but remains the same later. Thus, cholinergic-serotonergic interactions could play an important role in the treatment of depression.

  2. The Effect of Swimming Experience on Acquisition and Retention of Swimming-Based Taste Aversion Learning in Rats

    Science.gov (United States)

    Masaki, Takahisa; Nakajima, Sadahiko

    2010-01-01

    Swimming endows rats with an aversion to a taste solution consumed before swimming. The present study explored whether the experience of swimming before or after the taste-swimming trials interferes with swimming-based taste aversion learning. Experiment 1 demonstrated that a single preexposure to 20 min of swimming was as effective as four or…

  3. Influence of the brain sexual differentiation process on despair and antidepressant-like effect of fluoxetine in the rat forced swim test.

    Science.gov (United States)

    Gómez, M L; Martínez-Mota, L; Estrada-Camarena, E; Fernández-Guasti, A

    2014-03-07

    Sex differences exist in the depressive disorder prevalence and response to treatment. Several studies suggest that females respond better than males to the action of selective serotonin reuptake inhibitors (SSRIs), suggesting that gonadal hormones modulate mood and the response to these drugs. Sexual steroid hormones exert organizational actions (perennial and on early development) and activational effects (transient and on differentiated tissues). The aim of this study was to analyze sex differences in the forced swim test (FST) in animals without treatment and after fluoxetine (FLX, 0, 2.5, 5.0 and 10.0mg/kg). Initially, we compared male and female adult rats under control conditions or after altering their sexual differentiation process (at day 5 postnatally, PN, 60μg of testosterone propionate to females and male castration to induce or preclude masculinization, respectively). To further analyze if the sex differences depend on organizational or activational steroid hormone action we tested the same animals before and after adult gonadectomy. To prevent variations depending upon the estrous cycle, control and masculinized females were tested in estrus. Control females showed lower immobility and required lower doses of FLX (5mg/kg), to show an antidepressant-like effect, than males (10mg/kg), even after adult gonadectomy. In control males adult orchidectomy prevented FLX's action. Neonatally masculinized females exhibited analogous levels of immobility than control ones; before ovariectomy they responded to FLX similar to controls, but after the surgery they did not respond to fluoxetine. Neonatally orchidectomized males exhibited similar immobility values and response to FLX than control females. The findings suggest that the sex difference in despair depends on the hormones organizational effects and, in males, the response to FLX relies on organizational and activational actions. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  4. Effects of combined administration of 5-HT1A and/or 5-HT1B receptor antagonists and paroxetine or fluoxetine in the forced swimming test in rats.

    Science.gov (United States)

    Tatarczyńska, Ewa; Kłodzińska, Aleksandra; Chojnacka-Wójcik, Ewa

    2002-01-01

    Clinical data suggest that coadministration of pindolol, a 5-HT1A/5-HT1B/beta-adrenoceptor antagonist, and selective serotonin reuptake inhibitors (SSRIs) may shorten the time of onset of a clinical action and may increase beneficial effects of the therapy of drug-resistant depression. Effects of combined administration of SSRIs and 5-HT receptor ligands are currently evaluated in animal models for the detection of an antidepressant-like activity; however, the obtained results turned out to be inconsistent. The aim of the present study was to investigate effects of a 5-HT1A antagonist (WAY 100635), 5-HT1B antagonists (SB 216641 and GR 127935) or pindolol, given in combination with paroxetine or fluoxetine (SSRIs), in the forced swimming test in rats (Porsolt test). When given alone, paroxetine (10 and 20 mg/kg), fluoxetine (10 and 20 mg/kg), WAY 100635 (0.1 and 1 mg/kg), SB 216641 (2 mg/kg), GR 127935 (10 and 20 mg/kg) and pindolol (4 and 8 mg/kg) did not shorten the immobility time of rats in that test. Interestingly, SB 216641 administered alone at a dose of 4 mg/kg produced a significant reduction of the immobility time in that test. A combination of paroxetine (20 mg/kg) and WAY 100635 or pindolol failed to reveal a significant interaction; on the other hand, when paroxetine was given jointly with SB 216641 (2 mg/kg) or GR 127935 (10 and 20 mg/kg), that combination showed a significant antiimmobility action in the forced swimming test in rats. The active behaviors in that test did not reflect increased general activity because combined administration of both the 5-HT1B antagonists and paroxetine failed to alter the locomotor activity of rats, measured in the open field test. Coadministration of fluoxetine and all the antagonists used did not affect the behavior of rats in the forced swimming test. The obtained results seem to indicate that blockade of 5-HT1B receptors, but not 5-HT1A ones, can facilitate the antidepressant-like effect of paroxetine in the

  5. Effect of chronic forced swimming stress on whole brain radiation induced cognitive dysfunction and related mechanism

    International Nuclear Information System (INIS)

    Zhang Yuan; Sun Rui; Zhu Yaqun; Zhang Liyuan; Ji Jianfeng; Li Kun; Tian Ye

    2014-01-01

    Objective: To explore whether chronic forced swimming stress could improve whole brain radiation induced cognitive dysfunction and possible mechanism. Methods: Thirty-nine one month old male Sprague-Dawley rats were randomized into sham control group(C), swimming group(C-S), radiation group(R), and radiation plus swimming group(R-S). Radiation groups were given a single dose of 20 Gy on whole-brain. Rats in the swimming groups were trained with swimming of 15 min/d, 5 d/w. Rat behavior was performed 3 months after radiation in an order of free activity in an open field and the Morris water maze test including the place navigation and spatial probe tests. Then, the protein expressions of BDNF, P-ERK, T-ERK, P-CREB and T-CREB in the rat hippocampus tissue were assayed by Western blot. Results: On the day 2, in the place navigation test of Morris water maze, the latency of swimming group was significantly shorter than that of sham group, the latency of sham group was significantly shorter than that of radiation group, and the latency of radiation swimming group was significantly shorter than that of radiation group(P 0.05). Western blot assay showed that the expressions of BDNF and its downstream signals including P-ERK and P-CREB were markedly reduced by radiation (P < 0.05), but this reduction was attenuated by the chronic forced swimming stress. Conclusion: The chronic forced swimming stress could improve whole brain radiation induced cognitive dysfunction by up-regulating the expressions of BDNF and its downstream signal molecules of P-ERK and P-CREB in hippocampus. (authors)

  6. Omega-3 fatty acid deficient male rats exhibit abnormal behavioral activation in the forced swim test following chronic fluoxetine treatment: association with altered 5-HT1A and alpha2A adrenergic receptor expression.

    Science.gov (United States)

    Able, Jessica A; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K

    2014-03-01

    Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n = 34) or without (DEF, n = 30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n = 14) and DEF (n = 12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (-26%, p = 0.0001) and DEF + FLX (-32%, p = 0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF + FLX rats exhibited significantly greater climbing behavior compared with CON + FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF + FLX rats exhibited significant elevations in climbing behavior. DEF + FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON + FLX rats. DEF + FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. The Aqueous Crude Extracts of Montanoa frutescens and Montanoa grandiflora Reduce Immobility Faster Than Fluoxetine Through GABAA Receptors in Rats Forced to Swim.

    Science.gov (United States)

    Rodríguez-Landa, Juan Francisco; Cueto-Escobedo, Jonathan; Flores-Aguilar, Luis Ángel; Rosas-Sánchez, Gilberto Uriel; Rovirosa-Hernández, María de Jesús; García-Orduña, Francisco; Carro-Juárez, Miguel

    2018-01-01

    Montanoa frutescens and Montanoa grandiflora have been indistinctly used for centuries in traditional Mexican medicine for reproductive impairments, anxiety, and mood disorders. Preclinical studies support their aphrodisiac and anxiolytic properties, but their effects on mood are still unexplored. The effects of 25 and 50 mg/kg of M frutescens and M grandiflora extracts were evaluated on days 1, 7, 14, 21, and 28 of treatment, and compared with fluoxetine (1 mg/kg) and Remotiv (7.14 mg/kg) in Wistar rats. The participation of GABA A receptor in the effects produced by the treatments was explored. Montanoa extracts reduced immobility since day 1 of treatment, while fluoxetine and Remotiv required 14 days. The GABA A antagonism blocked the effects of Montanoa extracts, but not of fluoxetine or Remotiv. Montanoa extracts prevented quickly the stress-induced behaviors in the swimming test through action at the GABA A receptor, exerting a protective effect different to the typical antidepressants drugs.

  8. Glucocorticoids facilitate the retention of acquired immobility during forced swimming

    NARCIS (Netherlands)

    Veldhuis, H D; De Korte, C C; De Kloet, E R

    1985-01-01

    The adrenalectomy-induced decrease in the level of immobility during a 5 min retest period in the Porsolt swimming test could be reversed by glucocorticoids administered s.c. 15 min after the initial forced swimming exposure. The synthetic glucocorticoids dexamethasone and RU 28362 were active in

  9. Geometric Aspects of Force Controllability for a Swimming Model

    International Nuclear Information System (INIS)

    Khapalov, A. Y.

    2008-01-01

    We study controllability properties (swimming capabilities) of a mathematical model of an abstract object which 'swims' in the 2-D Stokes fluid. Our goal is to investigate how the geometric shape of this object affects the forces acting upon it. Such problems are of interest in biology and engineering applications dealing with propulsion systems in fluids

  10. Antisense to the glucocorticoid receptor in hippocampal dentate gyrus reduces immobility in forced swim test

    NARCIS (Netherlands)

    Korte, S.M.; de Kloet, E.R.; Buwalda, B; Bouman, S.D.; Bohus, B

    1996-01-01

    Immobility time of rats in the forced swim test was reduced after bilateral infusion of an 18-mer antisense phosphorothioate oligodeoxynucleotide targeted to the glucocorticoid receptor mRNA into the dentate gyrus of the hippocampus. Vehicle-, sense- and scrambled sequence-treated animals spent

  11. Ovarian and uterine alterations following forced swimming: An immunohistochemical study.

    Science.gov (United States)

    Seyed Saadat, Seyedeh Nazanin; Mohammadghasemi, Fahimeh; Ebrahimi, Hannan; Rafati Sajedi, Hanieh; Chatrnour, Gelayol

    2016-10-01

    Physical exercise is known to be a stressor stimulus that leads to reproductive disruption. The aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice. Adult mice (N=24) were divided into the following three groups: A, control; B, swimming in water (10 o C); and C, swimming in water (23 o C). Swimmers swam for 5 min daily for 5 consecutive days/ wk during 2 wks. An enzyme linked immunosorbent assay was used to determine serum estradiol, follicle stimulating hormone (FSH) and testosterone levels. Immunohistochemistry was performed to study apoptotic cells or estrogen receptor (ER) expression in uterine epithelial cells and ovaries. ANOVA was used for statistical analysis. Swimming in both groups reduced the serum FSH and estradiol levels (pForced swimming of 2 wks duration reduces the serum levels of FSH and estradiol without having effects on apoptosis in the ovaries or uteri of mice. Over a long period of time, forced swimming may have an adverse effect on fertility.

  12. Repeated exposure to corticosterone increases depression-like behavior in two different versions of the forced swim test without altering nonspecific locomotor activity or muscle strength.

    Science.gov (United States)

    Marks, Wendie; Fournier, Neil M; Kalynchuk, Lisa E

    2009-08-04

    We have recently shown that repeated high dose injections of corticosterone (CORT) reliably increase depression-like behavior on a modified one-day version of the forced swim test. The main purpose of this experiment was to compare the effect of these CORT injections on our one-day version of the forced swim test and the more traditional two-day version of the test. A second purpose was to determine whether altered behavior in the forced swim test could be due to nonspecific changes in locomotor activity or muscle strength. Separate groups of rats received a high dose CORT injection (40 mg/kg) or a vehicle injection once per day for 21 consecutive days. Then, half the rats from each group were exposed to the traditional two-day forced swim test and the other half were exposed to our one-day forced swim test. After the forced swim testing, all the rats were tested in an open field and in a wire suspension grip strength test. The CORT injections significantly increased the time spent immobile and decreased the time spent swimming in both versions of the forced swim test. However, they had no significant effect on activity in the open field or grip strength in the wire suspension test. These results show that repeated CORT injections increase depression-like behavior regardless of the specific parameters of forced swim testing, and that these effects are independent of changes in locomotor activity or muscle strength.

  13. Antidepressant behavioral effects of duloxetine and amitriptyline in the rat forced swimming test Efeitos antidepressivos da duloxetina e da amitriptilina no teste do nado forçado em ratos

    Directory of Open Access Journals (Sweden)

    Honório Sampaio Menezes

    2008-10-01

    Full Text Available PURPOSE: To compare the effects of the antidepressant drugs duloxetine and amitriptyline on depressive behaviors in rats. METHODS: Fifteen male Wistar rats were given systemic injections of duloxetine, amitriptyline or saline prior to a Forced Swimming Test (FST. Immobility and number of stops were measured. Data were analyzed by one-way ANOVA and Kruskall-Wallis. RESULTS: Rats given injections of duloxetine displayed fewer stops than the amitriptyline and control group (pOBJETIVO: Comparar o efeito antidepressivo da droga cloridrato de duloxetina com a amitriptilina. MÉTODOS: O teste do nado forçado, teste comportamental que avalia a atividade antidepressiva em ratos, foi utilizado em 15 ratos Wistar, machos adultos, divididos em três grupos iguais: duloxetina, amitriptilina e controle. Os dados foram analisados pelo teste One-way ANOVA e Kruskall-Wallis. RESULTADOS: Houve diferença significativa entre o número de paradas (p <0,05 entre os grupos duloxetina e amitriptilina e o grupo controle. Grupo amitriptilina e controle não apresentaram diferença (p=0,8. CONCLUSÃO: A duloxetina reduziu o comportamento depressivo sendo mais efetiva do que a amitriptilina.

  14. Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test Efeitos antidepressivos da duloxetina e da fluoxetina no teste do nado forçado em ratos

    Directory of Open Access Journals (Sweden)

    Leandro Ciulla

    2007-10-01

    Full Text Available PURPOSE: To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. METHODS: Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST. Immobility and number of stops were measured. RESULTS: Rats given injections of fluoxetine displayed significantly less immobility (p = 0.02 and fewer stops than the control group (p = 0.003. Duloxetine significanlty reduced the number of stops (p = 0.003, but did not effect immobility (p = 0.48. CONCLUSION: Duloxetine and fluoxetine reduced depressive behaviors in the Forced FST. However, our findings suggest that fluoxetine is more effective than duloxetine.OBJETIVO: Comparar o efeito antidepressivo da droga cloridrato de duloxetina com a fluoxetina. MÉTODOS: O teste do nado forçado, teste comportamental que avalia a atividade antidepressiva em ratos, foi utilizado em 18 ratos Wistar, machos adultos, divididos em três grupos iguais: duloxetina, fluoxetina e controle. RESULTADOS: Os dados do teste do nado forçado foram analisados pelo teste One-way ANOVA, Mann Whitney e Kruskall-Wallis.Houve diferença significativa (p = 0,003 entre o número de paradas dos grupos duloxetina e fluoxetina e o grupo controle. CONCLUSÃO: A duloxetina e a fluoxetina tiveram frequência de paradas similares. A fluoxetina mostrou ser mais efetiva que a duloxetina no teste do nado forçado em ratos.

  15. Forces and energetics of intermittent swimming

    Science.gov (United States)

    Floryan, Daniel; Van Buren, Tyler; Smits, Alexander J.

    2017-08-01

    Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry (PIV) flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.

  16. Enhanced anti-immobility effects of Sanggenon G isolated from the root bark of Morus alba combined with the α2-antagonist yohimbine in the rat forced swim test.

    Science.gov (United States)

    Lim, Dong Wook; Baek, Nam-In; Kim, Yun Tai; Lee, Changho; Kim, In-Ho; Han, Daeseok

    2016-07-01

    In this study, we aimed to determine whether Sanggenon G, an active compound isolated from the root bark of Morus alba, exhibited enhanced anti-immobility activity with the addition of the α2-antagonist yohimbine in rats subjected to forced swim test (FST)-induced depression. Fluoxetine (a selective serotonin reuptake inhibitor) treatment in rats reduced the immobility time, and pretreatment with yohimbine significantly enhanced the antidepressant-like behavior of fluoxetine at 5, 10 and 20 mg/kg. Similarly, Sanggenon G significantly decreased the immobility time, reducing immobility by a maximum of 43.9 % when treated at a dose of 20 mg/kg. Furthermore, pretreatment with yohimbine significantly enhanced the antidepressant-like behavior of Sanggenon G at 5 and 10 mg/kg. Our findings suggest that the antidepressant-like effect of Sanggenon G could be facilitated by concomitant use of the α2-antagonist. Further studies are needed to evaluate the potential of Sanggenon G as an alternative therapeutic approach for the treatment of depression.

  17. SWIMMING ENHANCES BONE MASS ACQUISITION IN GROWING FEMALE RATS

    Directory of Open Access Journals (Sweden)

    Joanne McVeigh

    2010-12-01

    Full Text Available Growing bones are most responsive to mechanical loading. We investigated bone mass acquisition patterns following a swimming or running exercise intervention of equal duration, in growing rats. We compared changes in bone mineral properties in female Sprague Dawley rats that were divided into three groups: sedentary controls (n = 10, runners (n = 8 and swimmers (n = 11. Runners and swimmers underwent a six week intervention, exercising five days per week, 30min per day. Running rats ran on an inclined treadmill at 0.33 m.s-1, while swimming rats swam in 25oC water. Dual energy X-ray absorptiometry scans measuring bone mineral content (BMC, bone mineral density (BMD and bone area at the femur, lumbar spine and whole body were recorded for all rats before and after the six week intervention. Bone and serum calcium and plasma parathyroid hormone (PTH concentrations were measured at the end of the 6 weeks. Swimming rats had greater BMC and bone area changes at the femur and lumbar spine (p < 0.05 than the running rats and a greater whole body BMC and bone area to that of control rats (p < 0.05. There were no differences in bone gain between running and sedentary control rats. There was no significant difference in serum or bone calcium or PTH concentrations between the groups of rats. A swimming intervention is able to produce greater beneficial effects on the rat skeleton than no exercise at all, suggesting that the strains associated with swimming may engender a unique mechanical load on the bone

  18. Chronic Fluoxetine Treatment Upregulates the Activity of the ERK1/2-NF-κB Signaling Pathway in the Hippocampus and Prefrontal Cortex of Rats Exposed to Forced-Swimming Stress.

    Science.gov (United States)

    Cui, Jingqiu; Yang, Kun; Yu, Xue; Wang, Jing-Lan; Li, Jie; Zhang, Yong; Li, Hengfen

    2016-01-01

    The aim of this study was to explore whether or not the antidepressant actions of fluoxetine (FLX) are correlated with extracellular signal-regulated kinase 1 and 2 (ERK1/2) and nuclear factor κ-light chain enhancer of activated B cells (NF-κB) in the hippocampus (HC) and prefrontal cortex (PFC) of rats. A total of 108 male Sprague-Dawley rats were randomly divided into 6 groups of 18 rats each. Group 1 was the control group, while group 2 comprised the depressed model in which rats were subjected to 28 days of forced-swimming stress (FST); groups 3-6 were also subjected to 28 days of FST and treated with FLX once a day for 1 day (group 3; F1d), 1 week (group 4; F1w), 2 weeks (group 5; F2w), or 4 weeks (group 6; F4w). The control group was not subjected to FST or treated with FLX. Behavior tests that included the Morris water maze (MWM) and saccharin preference were performed, and ERK1/2 and NF-κB proteins were assayed using Western blot. The rats in the control group and in groups 5 and 6 (F2w and F4w, respectively) had a significantly shorter average escape latency, needed more attempts in order to successfully cross the platform, and had a greater saccharin preference than those in the depressed group (p < 0.05). In the depressed group, the phosphorylated ERK1/2 (p-ERK1/2) and phosphorylated NF-κB (p-NF-κB) expression in the HC and PFC were lower than in the control group (p < 0.05). Treatment with FLX reversed the changes in the expression of p-ERK1/2 and p-NF-κB in rats in the F2w and F4w groups. In this study, FLX treatment for 2 weeks or longer reversed the impaired spatial learning, memory, and anhedonia observed in the depressed model rats and upregulated the activities of the ERK1/2-NF-κB signaling pathway. © 2016 S. Karger AG, Basel.

  19. Hypericum perforatum L. treatment restored bone mass changes in swimming stressed rats.

    Science.gov (United States)

    Seferos, Nikos; Petrokokkinos, Loukas; Kotsiou, Antonia; Rallis, George; Tesseromatis, Christine

    2016-01-01

    Stress, via corticosteroids release, influences bone mass density. Hypericum perforatum (Hp) a traditional remedy possess antidepressive activity (serotonin reuptake inhibitor) and wound healing properties. Hp preparation contains mainly hypericin, hyperforin, hyperoside and flavonoids exerting oestrogen-mimetic effect. Cold swimming represents an experimental model of stress associating mental strain and corporal exhaustion. This study investigates the Hp effect on femur and mandible bone mass changes in rats under cold forced swimming procedure. 30 male Wistar rats were randomized into three groups. Group A was treated with Methanolic extract of Hp (Jarsin®) via gastroesophageal catheter, and was submitted to cold swimming stress for 10 min/daily. Group B was submitted to cold stress, since group C served as control. Experiment duration was 10 days. Haematocrite and serum free fatty acids (FFA) were estimated. Furthermore volume and specific weight of each bone as well as bone mass density via dual energy X-Ray absorptiometry (DEXA) were measured. Statistic analysis by t-test. Hp treatment restores the stress injuries. Adrenals and bone mass density regain their normal values. Injuries occurring by forced swimming stress in the rats are significantly improved by Hp treatment. Estrogen-like effects of Hp flavonoids eventually may act favorable in bone remodeling.

  20. Individual differences in the elevated plus-maze and the forced swim test.

    Science.gov (United States)

    Estanislau, Celio; Ramos, Anna Carolina; Ferraresi, Paula Daniele; Costa, Naiara Fernanda; de Carvalho, Heloisa Maria Cotta Pires; Batistela, Silmara

    2011-01-01

    The elevated plus-maze is an apparatus composed of enclosed and open (elevated) arms and time spent in the open arms by a rat can be increased/decreased by anxiolytic/anxiogenic agents. In the forced swim test, floating behavior is used as an index of behavioral despair and can be decreased by antidepressant agents. As the comorbidity between anxiety and depression is a remarkable issue in human behavioral disorders, a possible relationship between the behaviors seen in the cited tests is of great relevance. In the present study, fifty-four male rats (Rattus norvegicus) were submitted to a plus-maze session and to a 2-day forced swim protocol. According to their time in the open arms, they were divided into three groups: Low Open, Medium Open and High Open. Some plus-maze measures were found to be coherent with time in the open arms and are suggested to also be reliable anxiety indexes. In the forced swim test, the Low Open group showed decreases in floating duration from forced swim Session 1 to Session 2, an alteration opposite to that observed in the other groups (particularly, the Medium Open group). The Low Open group also showed increases in floating latency, again in sharp contrast with the alteration found in the other groups. Accordingly, positive and negative correlation were found between time in the open arms and floating duration and latency, respectively. Results are compared to previous studies and mediation of the effect by reactivity to aversive stimulation or alterations induced by open arm exposure is discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. Nerve growth factor (NGF) immunoreactive neurons in the juvenile rat hippocampus: response to acute and long-term high-light open-field (HL-OF) or forced swim (FS) stress stimulation.

    Science.gov (United States)

    Badowska-Szalewska, E; Spodnik, E; Ludkiewicz, B; Klejbor, I; Moryś, J

    2011-12-29

    This study aimed at examining and comparing the influence of two different stress stimuli on the density (number of cells/mm²) of nerve growth factor (NGF) containing neurons in the hippocampal CA1 and CA3 pyramidal cell layers and the dentate gyrus (DG) granule cell layer in juvenile rats (P28; P-postnatal day). The high-light open-field (HL-OF) test and forced swim (FS) test were employed to investigate the effects of a single, 15-min acute exposure and repeated (15 min daily for 21 days) long-term exposure to stress. In order to detect NGF-ir neurons, immunohistochemical (-ir) techniques were used. In comparison with nonstressed animals, acute and long-term HL-OF or FS stimulation resulted in a marked increase (P<0.001) in the density of NGF-ir containing cells in all the hippocampal structures. The frequency of stress application (acute vs. long-term), however, did not have a substantial impact on the studied parameter, with the exception of the CA3 sector, where a decreased density (P<0.001) of NGF-ir neurons was observed after long-term exposure to FS. It may be concluded that a rise in the density of NGF-ir neurons in the juvenile rat hippocampus after exposure to HL-OF or FS stressors could have affected the activity of the hypothalamic-pituitary-adrenocortical (HPA) stress axis. Prolonged HL-OF or FS stress was probably aggravating enough not to trigger the habituation process. The type of stressor applied (HL-OF vs. FS) was not essentially a factor determining the density of NGF-ir cells in the hippocampus. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. Intensity of swimming exercise influences aortic reactivity in rats

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    A.F. Brito

    2015-11-01

    Full Text Available Exercise is known to cause a vasodilatory response; however, the correlation between the vasorelaxant response and different training intensities has not been investigated. Therefore, this study evaluated the vascular reactivity and lipid peroxidation after different intensities of swimming exercise in rats. Male Wistar rats (aged 8 weeks; 250-300 g underwent forced swimming for 1 h whilst tied to loads of 3, 4, 5, 6, and 8% of their body weight, respectively (groups G3, G4, G5, G6 and G8, respectively; n=5 each. Immediately after the test, the aorta was removed and suspended in an organ bath. Cumulative relaxation in response to acetylcholine (10−12-10−4 M and contraction in response to phenylephrine (10−12-10−5 M were measured. Oxidative stress was estimated by determining malondialdehyde concentration. The percentages of aorta relaxation were significantly higher in G3 (7.9±0.20, G4 (7.8±0.29, and G5 (7.9±0.21, compared to the control group (7.2±0.04, while relaxation in the G6 (7.4±0.25 and G8 (7.0±0.06 groups was similar to the control group. In contrast, the percentage of contraction was significantly higher in G6 (8.8 ±0.1 and G8 (9.7±0.29 compared to the control (7.1±0.1, G3 (7.3±0.2, G4 (7.2±0.1 and G5 (7.2±0.2% groups. Lipid peroxidation levels in the aorta were similar to control levels in G3, G4 and G5, but higher in G6 and G8, and significantly higher in G8 (one-way ANOVA. These results indicate a reduction in vasorelaxing activity and an increase in contractile activity in rat aortas after high-intensity exercise, followed by an increase in lipid peroxidation.

  3. A Forced Damped Oscillation Framework for Undulatory Swimming Provides New Insights into How Propulsion Arises in Active and Passive Swimming

    Science.gov (United States)

    Bhalla, Amneet Pal Singh; Griffith, Boyce E.; Patankar, Neelesh A.

    2013-01-01

    A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions (“active” swimming) or by forces imparted by the surrounding fluid (“passive” swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained. PMID:23785272

  4. A forced damped oscillation framework for undulatory swimming provides new insights into how propulsion arises in active and passive swimming.

    Science.gov (United States)

    Bhalla, Amneet Pal Singh; Griffith, Boyce E; Patankar, Neelesh A

    2013-01-01

    A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions ("active" swimming) or by forces imparted by the surrounding fluid ("passive" swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.

  5. A forced damped oscillation framework for undulatory swimming provides new insights into how propulsion arises in active and passive swimming.

    Directory of Open Access Journals (Sweden)

    Amneet Pal Singh Bhalla

    Full Text Available A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions ("active" swimming or by forces imparted by the surrounding fluid ("passive" swimming, is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.

  6. Physical forces shape group identity of swimming Pseudomonas putida cells

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    David Rodriguez-Espeso

    2016-09-01

    Full Text Available The often striking macroscopic patterns developed by motile bacterial populations on agar plates are a consequence of the environmental conditions where the cells grow and spread. Parameters such as medium stiffness and nutrient concentration have been reported to alter cell swimming behavior, while mutual interactions among populations shape collective patterns. One commonly observed occurrence is the mutual inhibition of clonal bacteria when moving towards each other, which results in a distinct halt at a finite distance on the agar matrix before having direct contact. The dynamics behind this phenomenon (i.e. intolerance to mix in time and space with otherwise identical others has been traditionally explained in terms of cell-to-cell competition/cooperation regarding nutrient availability. In this work, the same scenario has been revisited from an alternative perspective: the effect of the physical mechanics that frame the process, in particular the consequences of collisions between moving bacteria and the semi-solid matrix of the swimming medium. To this end we set up a simple experimental system in which the swimming patterns of Pseudomonas putida were tested with different geometries and agar concentrations. A computational analysis framework that highlights cell-to-medium interactions was developed to fit experimental observations. Simulated outputs suggested that the medium is compressed in the direction of the bacterial front motion. This phenomenon generates what was termed a compression wave that goes through the medium preceding the swimming population and that determines the visible high-level pattern. Taken together, the data suggested that the mechanical effects of the bacteria moving through the medium created a factual barrier that impedes to merge with neighboring cells swimming from a different site. The resulting divide between otherwise clonal bacteria is thus brought about by physical forces –not genetic or metabolic

  7. Omega-3 Fatty Acid Deficiency Does Not Alter the Effects of Chronic Fluoxetine Treatment on Central Serotonin Turnover or Behavior in the Forced Swim Test in Female Rats

    OpenAIRE

    McNamara, Robert K.; Able, Jessica A.; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; Lipton, Jack W.

    2013-01-01

    While translational evidence suggests that long-chain omega-3 fatty acid status is positively associated with the efficacy of selective serotonin reuptake inhibitor drugs, the neurochemical mechanisms mediating this interaction are not known. Here we investigated the effects of dietary omega-3 (n-3) fatty acid insufficiency on the neurochemical and behavioral effects of chronic fluoxetine (FLX) treatment. Female rats were fed diets with (CON, n=56) or without (DEF, n=40) the n-3 fatty acids d...

  8. Neonatal treatment with fluoxetine reduces depressive behavior induced by forced swim in adult rats Tratamento neonatal com fluoxetina reduz o comportameto depressivo induzido pelo nado forçado em ratos adultos

    Directory of Open Access Journals (Sweden)

    Cristiano Mendes-da-Silva

    2002-12-01

    Full Text Available Serotonin plays a role at the pathophysiology of depression in humans and in experimental models. The present study investigated the depressive behavior and the weigh evolution in adult rats (60 days treated from the 1st to the 21st postnatal day with fluoxetine, a selective serotonin reuptake inhibitor (10 mg/kg, sc, daily. The depressive behavior was induced by the forced swim test (FST. The animals were submitted to two sessions of FST: 1st session for 15 min and the 2nd session 24h later, for 5 min. During the 2nd session the Latency of the Attempt of Escape (LAE and Behavioral Immobility (BI were appraised. The Fluoxetine group when compared to the Control group, showed an increase in LAE and a decrease in BI. The neonatal administration of fluoxetine reduced the depressive behavior in adult rats, possibly by increase in the brain serotonergic activity. This alteration can be associated to process of neuroadaptation.Estudos em humanos e em modelos experimentais demonstram que a serotonina (5-HT participa da fisiopatologia da depressão. O presente estudo investigou o comportamento depressivo e a evolução ponderal de ratos adultos jovens (60 dias tratados do 1º ao 21º dia pós-natal com fluoxetina, um inibidor seletivo de recaptação da serotonina, (10 mg/kg, sc, diariamente. A depressão experimental foi induzida através do teste de nado forçado (NF. Os animais foram submetidos a duas sessões de NF, a primeira por 15 min e a segunda após 24 h, por 5 min. Durante os 5 min de NF a latência da tentativa de fuga (LTF e o tempo de imobilidade (TI foram avaliados. O grupo tratado com fluoxetina apresentou aumento da LTF e redução do TI comparado ao controle. A administração neonatal de fluoxetina reduziu o comportamento depressivo em ratos adultos, possivelmente em função do aumento da atividade serotoninérgica cerebral. Esta alteração poderá estar relacionada a processos neuroadaptativos.

  9. Drag force and jet propulsion investigation of a swimming squid

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    Tabatabaei Mahdi

    2015-01-01

    Full Text Available In this study, CAD model of a squid was obtained by taking computer tomography images of a real squid. The model later placed into a computational domain to calculate drag force and performance of jet propulsion. The drag study was performed on the CAD model so that drag force subjected to real squid was revealed at squid’s different swimming speeds and comparison has been made with other underwater creatures (e.g., a dolphin, sea lion and penguin. The drag coefficient (referenced to total wetted surface area of squid is 0.0042 at Reynolds number 1.6x106 that is a %4.5 difference from Gentoo penguin. Besides, jet flow of squid was simulated to observe the flow region generated in the 2D domain utilizing dynamic mesh method to mimic the movement of squid’s mantle cavity.

  10. Just Keep Swimming: Neuroendocrine, Metabolic, and Behavioral Changes After a Forced Swimming Test in Zebrafish.

    Science.gov (United States)

    da Rosa, João Gabriel Santos; Barcellos, Heloísa Helena de Alcântara; Idalencio, Renan; Marqueze, Alessandra; Fagundes, Michele; Rossini, Mainara; Variani, Cristiane; Balbinoti, Francine; Tietböhl, Tássia Michele Huff; Rosemberg, Denis Broock; Barcellos, Leonardo José Gil

    2017-02-01

    In this study, we show that an adaptation of the spinning test can be used as a model to study the exercise-exhaustion-recovery paradigm in fish. This forced swimming test promotes a wide range of changes in the hypothalamus-pituitary-interrenal axis functioning, intermediary metabolism, as well in fish behavior at both exercise and recovery periods. Our results pointed that this adapted spinning test can be considered a valuable tool for evaluating drugs and contaminant effects on exercised fish. This can be a suitable protocol both to environmental-to evaluate contaminants that act in fish energy mobilization and recovery after stressors-and translational perspectives-effects of drugs on exercised or stressed humans.

  11. Swimming: Effects on Stress Urinary Incontinence and the Expression of Nerve Growth Factor in Rats Following Transabdominal Urethrolysis

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    Il Gyu Ko

    2011-06-01

    Full Text Available PurposeStress urinary incontinence (SUI commonly occurs in women, and it has an enormous impact on quality of life. Surgery, drugs, and exercise have been recommended for the treatment of this disease. Among these, exercise is known to be effective for the relief of symptoms of SUI; however, the efficacy and underlying mechanisms of the effect of exercise on SUI are poorly understood. We investigated the effect of swimming the symptom of SUI in relation to the expression of nerve growth factor (NGF in rats.MethodsTransabdominal urethrolysis was used to induce SUI, in Sprague-Dawley rats. The experimental groups were divided into the following three groups: sham-operation group, transabdominal urethrolysis-induced group, and transabdominal urethrolysis-induced and swimming group. The rats in the swimming group were forced to swim for 30 minutes once daily starting 2 weeks after SUI induction and continuing for 4 weeks. For this study, determination of abdominal leak point pressure and immunohistochemistry for NGF in the urethra and in the neuronal voiding centers (medial preoptic nucleus [MPA], ventrolateral periaqueductal gray [vlPAG], pontine micturition center [PMC], and spinal cord [L4-L5] were performed.ResultsTransabdominal urethrolysis significantly reduced the abdominal leak point pressure, thereby contributing to the induction of SUI. Abdominal leak point pressure, however, was significantly improved by swimming. The expression of NGF in the urethra and in the neuronal voiding centers (MPA, vlPAG, PMC, and L4-L5 relating to micturition was enhanced by the induction of SUI. Swimming, however, significantly suppressed SUI-induced NGF expression.ConclusionsSwimming alleviated symptoms of transabdominal urethrolysis-induced SUI, as assessed by an increase in abdominal leak point pressure. The underlying mechanisms of these effects of swimming might be ascribed to the inhibitory effect of swimming on NGF expression.

  12. Antidepressant effect of Melissa officinalis in the forced swimming test

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    M Emamghoreishi

    2009-03-01

    Full Text Available ABSTRACT Background: In Iranian and other traditional medicines, an antidepressant effect has been indicated for Melissa officinalis (Lamiaceae. However, studies showing its antidepressant effect is lacking. Therefore, the present study was undertaken to examine whether the aqueous extract and essential oil from leaves of Melissa officinalis have an antidepressant-like activity in mice.  Materials and Methods: The effect of subchronic administration of different doses of the aqueous extract (25, 75, 150, 300 mg/kg or water; n=9-10 and the essential oil (10, 25, 75, 150, 300 mg/kg or almond oil; n=9-10 on immobility, climbing, and swimming behaviors were evaluated in the forced swimming test. Fluoxetine (20mg/kg and imipramine (15 mg/kg were used as reference drugs. Additionally, the effect of both plant preparations on spontaneous activity was examined. Results: All doses of the aqueous extract, used in this study, produced a significant reduction in immobility along with an increase in climbing behavior which is similar to those which have been observed with imipramine. Essential oil caused a dose-dependent reduction in immobility and an increase in climbing at all studied doses, compared to control group. Only the highest dose (300mg/kg of essential oil showed a significant increase in swimming behavior. The aqueous extract, but not the essential oil, decreased spontaneous activity in a dose dependent manner. Conclusion: The results of this study suggests that the Melissa officinalis possess an antidepressant-like activity similar to imipramine which may have a potential clinical value for treatment of depression.

  13. Toxic cocaine- and convulsant-induced modification of forced swimming behaviors and their interaction with ethanol: comparison with immobilization stress

    Science.gov (United States)

    Hayase, Tamaki; Yamamoto, Yoshiko; Yamamoto, Keiichi

    2002-01-01

    Background Swimming behaviors in the forced swimming test have been reported to be depressed by stressors. Since toxic convulsion-inducing drugs related to dopamine [cocaine (COC)], benzodiazepine [methyl 6,7-dimethoxy-4-ethyl-β-carboline-carboxylate (DMCM)], γ-aminobutyric acid (GABA) [bicuculline (BIC)], and glutamate [N-methyl-D-aspartate (NMDA)] receptors can function as stressors, the present study compared their effects on the forced swimming behaviors with the effects of immobilization stress (IM) in rats. Their interactions with ethanol (EtOH), the most frequently coabused drug with COC which also induces convulsions as withdrawal symptoms but interferes with the convulsions caused by other drugs, were also investigated. Results Similar to the IM (10 min) group, depressed swimming behaviors (attenuated time until immobility and activity counts) were observed in the BIC (5 mg/kg IP) and DMCM (10 mg/kg IP) groups at the 5 h time point, after which no toxic behavioral symptoms were observed. However, they were normalized to the control levels at the 12 h point, with or without EtOH (1.5 g/kg IP). In the COC (60 mg/kg IP) and NMDA (200 mg/kg IP) groups, the depression occurred late (12 h point), and was normalized by the EtOH cotreatment. At the 5 h point, the COC treatment enhanced the swimming behaviors above the control level. Conclusions Although the physiological stress (IM), BIC, and DMCM also depressed the swimming behaviors, a delayed occurrence and EtOH-induced recovery of depressed swimming were observed only in the COC and NMDA groups. This might be correlated with the previously-reported delayed responses of DA and NMDA neurons rather than direct effects of the drugs, which could be suppressed by EtOH. Furthermore, the characteristic psychostimulant effects of COC seemed to be correlated with an early enhancement of swimming behaviors. PMID:12425723

  14. Gastrodia elata Bl. Attenuated learning deficits induced by forced-swimming stress in the inhibitory avoidance task and Morris water maze.

    Science.gov (United States)

    Chen, Pei-Ju; Liang, Keng-Chen; Lin, Hui-Chen; Hsieh, Ching-Liang; Su, Kuan-Pin; Hung, Mei-Chu; Sheen, Lee-Yan

    2011-06-01

    This study adopted the forced-swimming paradigm to induce depressive symptoms in rats and evaluated the effects on learning and memory processing. Furthermore, the effects of the water extract of Gastrodia elata Bl., a well-known Chinese traditional medicine, on amnesia in rats subjected to the forced-swimming procedure were studied. Rats were subjected to the forced-swimming procedure, and the inhibitory avoidance task and Morris water maze were used to assess learning and memory performance. The acquisition of the two tasks was mostly impaired after the 15-minute forced-swimming procedure. Administration of the water extract of G. elata Bl. for 21 consecutive days at a dosage of 0.5 or 1.0 g/kg of body weight significantly improved retention in the inhibitory avoidance test, and the lower dose showed a better effect than the higher one and the antidepressant fluoxetine (18 mg/kg of body weight). In the Morris water maze, the lower dose of the water extract of G. elata Bl. significantly improved retention by shortening escape latency in the first test session and increasing the time in searching the target zone during the probe test. These findings suggest that water extracts of G. elata Bl. ameliorate the learning and memory deficits induced by forced swimming.

  15. Forced swimming test and fluoxetine treatment: in vivo evidence that peripheral 5-HT in rat platelet-rich plasma mirrors cerebral extracellular 5-HT levels, whilst 5-HT in isolated platelets mirrors neuronal 5-HT changes.

    Science.gov (United States)

    Bianchi, M; Moser, C; Lazzarini, C; Vecchiato, E; Crespi, F

    2002-03-01

    Low levels of central serotonin (5-HT) have been related to the state of depression, and 5-HT is the major target of the newer antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs). Neurons and platelets display structural and functional similarities, so that the latter have been proposed as a peripheral model of central functions. In particular, in blood more than 99% of 5-HT is contained in platelets, so that one could consider changes in 5-HT levels in platelets as a mirror of changes in central 5-HT. Here, this hypothesis has been studied via the analysis of the influence of: (1) the forced swimming test (FST, which has been proved to be of utility to predict the clinical efficacy of antidepressants in rodents) and (2) treatment with the SSRI fluoxetine upon 5-HT levels monitored in brain regions and in peripheral platelets by means of electrochemical in vivo and ex vivo measurements. The results obtained confirm that the FST increases immobility; furthermore they show a parallel and significant decrease in cerebral (brain homogenate) and peripheral (in platelet-rich plasma, PRP) voltammetric 5-HT levels following the FST in naive rats. In addition, subchronic treatment with fluoxetine was followed by a significant increase in 5-HT levels in PRP, while the same SSRI treatment performed within the FST resulted in a decrease in the 5-HT levels in PRP. However, this decrease was inferior to that observed without SSRI treatment. These data suggest that there is an inverse relationship between immobility and the levels of 5-HT in PRP and that these peripheral 5-HT levels are sensitive to: (1) the FST, (2) the treatment with fluoxetine and (3) the combination of both treatments, i.e. SSRI + FST. It has been reported that SSRI treatment at first inhibits the 5-HT transporter in brain, resulting in increased extracellular 5-HT, while following sustained SSRI treatments decreased intracellular levels of central 5-HT were observed. Accordingly, the

  16. Antidepressant-like effects of Tagetes lucida Cav. in the forced swimming test.

    Science.gov (United States)

    Guadarrama-Cruz, G; Alarcon-Aguilar, F J; Lezama-Velasco, R; Vazquez-Palacios, G; Bonilla-Jaime, H

    2008-11-20

    Tagetes lucida (Asteraceae), has been referred in Mexican traditional medicine for the treatment of different central nervous system (CNS) diseases, mainly depression. Nevertheless, the available scientific information about this species is scarce and there are no reports related to its possible effect on the CNS. In this work, the antidepressant-like effect of extract of Tagetes lucida was evaluated in rats, as well as its potential adverse effects on male sexual behavior (MSB). Antidepressant activity was studied using forced swimming test (FST), motor activity in the open-field test and on MSB in sexually experienced male. The aqueous extract of Tagetes lucida in doses of 5, 10, 50, 100 and 200mg/(kgday)(-1) were administered orally for 14 consecutive days and evaluated on day 14, 2h after the last dose treatment. Fluoxetine (10mg/(kgday)(-1), p.o.) was used as the control positive. The aqueous extract (10, 50, 100mg/(kgday)(-1)) significantly reduced immobility and increased swimming without affecting climbing behavior in the FST. These same doses were not able to modify neither the motor activity nor the MSB. These data indicate that the extract of Tagetes lucida possesses antidepressant-like properties in rats.

  17. Factors influencing behavior in the forced swim test

    Science.gov (United States)

    Bogdanova, Olena V.; Kanekar, Shami; D’Anci, Kristen E.; Renshaw, Perry F.

    2017-01-01

    The forced swim test (FST) is a behavioral test in rodents which was developed in 1978 by Porsolt and colleagues as a model for predicting the clinical efficacy of antidepressant drugs. A modified version of the FST added the classification of active behaviors into swimming and climbing, in order to facilitate the differentiation between serotonergic and noradrenergic classes of antidepressant drugs. The FST is now widely used in basic research and the pharmaceutical screening of potential antidepressant treatments. It is also one of the most commonly used tests to assess depressive-like behavior in animal models. Despite the simplicity and sensitivity of the FST procedure, important differences even in baseline immobility rates have been reported between different groups, which complicate the comparison of results across studies. In spite of several methodological papers and reviews published on the FST, the need still exists for clarification of factors which can influence the procedure. While most recent reviews have focused on antidepressant effects observed with the FST, this one considers the methodological aspects of the procedure, aiming to summarize issues beyond antidepressant action in the FST. The previously published literature is analyzed for factors which are known to influence animal behavior in the FST. These include biological factors, such as strain, age, body weight, gender and individual differences between animals; influence of preconditioning before the FST: handling, social isolation or enriched environment, food manipulations, various kinds of stress, endocrine manipulations and surgery; schedule and routes of treatment, dosage and type of the drugs as well as experimental design and laboratory environmental effects. Consideration of these factors in planning experiments may result in more consistent FST results. PMID:23685235

  18. Critical force during tethered swimming for the evaluation of aerobic capacity and prediction of performances in freestyle swimming

    OpenAIRE

    Marcelo Papoti; Ricardo Vitório; Gustavo Gomes Araújo; Luiz Eduardo Barreto Martins; Sérgio Augusto Cunha; Claudio Alexandre Gobatto

    2010-01-01

    The present study investigated the relationship of critical force (Fcrit) with lactate threshold (LLNA) and the intensity corresponding to VO2max (iVO2max) in tethered swimming (TS), and their correlation with maximal performance in 400-m (V400) and 30-min (VT30) freestyle swimming (FS). Seven swimmers were submitted to a TS incremental test for the determination of LLNA and iVO2max. For the determination of Fcrit, the swimmers performed four exercises to exhaustion at intensities (F) corresp...

  19. Effect of potassium channel modulators in mouse forced swimming test

    Science.gov (United States)

    Galeotti, Nicoletta; Ghelardini, Carla; Caldari, Bernardetta; Bartolini, Alessandro

    1999-01-01

    The effect of intracerebroventricular (i.c.v.) administration of different potassium channel blockers (tetraethylammonium, apamin, charybdotoxin, gliquidone), potassium channel openers (pinacidil, minoxidil, cromakalim) and aODN to mKv1.1 on immobility time was evaluated in the mouse forced swimming test, an animal model of depression. Tetraethylammonium (TEA; 5 μg per mouse i.c.v.), apamin (3 ng per mouse i.c.v.), charybdotoxin (1 μg per mouse i.c.v.) and gliquidone (6 μg per mouse i.c.v.) administered 20 min before the test produced anti-immobility comparable to that induced by the tricyclic antidepressants amitriptyline (15 mg kg−1 s.c.) and imipramine (30 mg kg−1 s.c.). By contrast pinacidil (10–20 μg per mouse i.c.v.), minoxidil (10–20 μg per mouse i.c.v.) and cromakalim (20–30 μg per mouse i.c.v.) increased immobility time when administered in the same experimental conditions. Repeated administration of an antisense oligonucleotide (aODN) to the mKv1.1 gene (1 and 3 nmol per single i.c.v. injection) produced a dose-dependent increase in immobility time of mice 72 h after the last injection. At day 7, the increasing effect produced by aODN disappeared. A degenerate mKv1.1 oligonucleotide (dODN), used as control, did not produce any effect in comparison with saline- and vector-treated mice. At the highest effective dose, potassium channels modulators and the mKv1.1 aODN did not impair motor coordination, as revealed by the rota rod test, nor did they modify spontaneous motility as revealed by the Animex apparatus. These results suggest that modulation of potassium channels plays an important role in the regulation of immobility time in the mouse forced swimming test. PMID:10323599

  20. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi)

    NARCIS (Netherlands)

    Palstra, A.P.; Mes, D.; Kusters, K.; Roques, J.A.C.; Flik, G.; Kloet, K.; Blonk, R.J.W.

    2015-01-01

    Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (U-opt in m s(-1) or body lengths s(-1), BL s(-1)) were assessed and then applied to determine the effects of long-term forced and

  1. Arctigenin enhances swimming endurance of sedentary rats partially by regulation of antioxidant pathways.

    Science.gov (United States)

    Wu, Ruo-ming; Sun, Yan-yan; Zhou, Ting-ting; Zhu, Zhi-yuan; Zhuang, Jing-jing; Tang, Xuan; Chen, Jing; Hu, Li-hong; Shen, Xu

    2014-10-01

    Arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan found in traditional Chinese herbs, has been determined to exhibit a variety of pharmacological activities, including anti-tumor, anti-inflammation, neuroprotection, and endurance enhancement. In the present study, we investigated the antioxidation and anti-fatigue effects of arctigenin in rats. Rat L6 skeletal muscle cell line was exposed to H2O2 (700 μmol/L), and ROS level was assayed using DCFH-DA as a probe. Male SD rats were injected with arctigenin (15 mg·kg(-1)·d(-1), ip) for 6 weeks, and then the weight-loaded forced swimming test (WFST) was performed to evaluate their endurance. The levels of antioxidant-related genes in L6 cells and the skeletal muscles of rats were analyzed using real-time RT-PCR and Western blotting. Incubation of L6 cells with arctigenin (1, 5, 20 μmol/L) dose-dependently decreased the H2O2-induced ROS production. WFST results demonstrated that chronic administration of arctigenin significantly enhanced the endurance of rats. Furthermore, molecular biology studies on L6 cells and skeletal muscles of the rats showed that arctigenin effectively increased the expression of the antioxidant-related genes, including superoxide dismutase (SOD), glutathione reductase (Gsr), glutathione peroxidase (GPX1), thioredoxin (Txn) and uncoupling protein 2 (UCP2), through regulation of two potential antioxidant pathways: AMPK/PGC-1α/PPARα in mitochondria and AMPK/p53/Nrf2 in the cell nucleus. Arctigenin efficiently enhances rat swimming endurance by elevation of the antioxidant capacity of the skeletal muscles, which has thereby highlighted the potential of this natural product as an antioxidant in the treatment of fatigue and related diseases.

  2. Arctigenin enhances swimming endurance of sedentary rats partially by regulation of antioxidant pathways

    Science.gov (United States)

    Wu, Ruo-ming; Sun, Yan-yan; Zhou, Ting-ting; Zhu, Zhi-yuan; Zhuang, Jing-jing; Tang, Xuan; Chen, Jing; Hu, Li-hong; Shen, Xu

    2014-01-01

    Aim: Arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan found in traditional Chinese herbs, has been determined to exhibit a variety of pharmacological activities, including anti-tumor, anti-inflammation, neuroprotection, and endurance enhancement. In the present study, we investigated the antioxidation and anti-fatigue effects of arctigenin in rats. Methods: Rat L6 skeletal muscle cell line was exposed to H2O2 (700 μmol/L), and ROS level was assayed using DCFH-DA as a probe. Male SD rats were injected with arctigenin (15 mg·kg−1·d−1, ip) for 6 weeks, and then the weight-loaded forced swimming test (WFST) was performed to evaluate their endurance. The levels of antioxidant-related genes in L6 cells and the skeletal muscles of rats were analyzed using real-time RT-PCR and Western blotting. Results: Incubation of L6 cells with arctigenin (1, 5, 20 μmol/L) dose-dependently decreased the H2O2-induced ROS production. WFST results demonstrated that chronic administration of arctigenin significantly enhanced the endurance of rats. Furthermore, molecular biology studies on L6 cells and skeletal muscles of the rats showed that arctigenin effectively increased the expression of the antioxidant-related genes, including superoxide dismutase (SOD), glutathione reductase (Gsr), glutathione peroxidase (GPX1), thioredoxin (Txn) and uncoupling protein 2 (UCP2), through regulation of two potential antioxidant pathways: AMPK/PGC-1α/PPARα in mitochondria and AMPK/p53/Nrf2 in the cell nucleus. Conclusion: Arctigenin efficiently enhances rat swimming endurance by elevation of the antioxidant capacity of the skeletal muscles, which has thereby highlighted the potential of this natural product as an antioxidant in the treatment of fatigue and related diseases. PMID:25152028

  3. A proposal for refining the forced swim test in Swiss mice.

    Science.gov (United States)

    Costa, Ana Paula Ramos; Vieira, Cintia; Bohner, Lauren O L; Silva, Cristiane Felisbino; Santos, Evelyn Cristina da Silva; De Lima, Thereza Christina Monteiro; Lino-de-Oliveira, Cilene

    2013-08-01

    The forced swim test (FST) is a preclinical test to the screening of antidepressants based on rats or mice behaviours, which is also sensitive to stimulants of motor activity. This work standardised and validated a method to register the active and passive behaviours of Swiss mice during the FST in order to strength the specificity of the test. Adult male Swiss mice were subjected to the FST for 6 min without any treatment or after intraperitoneal injection of saline (0.1 ml/10 g), antidepressants (imipramine, desipramine, or fluoxetine, 30 mg/kg) or stimulants (caffeine, 30 mg/kg or apomorphine, 10mg/kg). The latency, frequency and duration of behaviours (immobility, swimming, and climbing) were scored and summarised in bins of 6, 4, 2 or 1 min. Parameters were first analysed using Principal Components Analysis generating components putatively related to antidepressant (first and second) or to stimulant effects (third). Antidepressants and stimulants affected similarly the parameters grouped into all components. Effects of stimulants on climbing were better distinguished of antidepressants when analysed during the last 4 min of the FST. Surprisingly, the effects of antidepressants on immobility were better distinguished from saline when parameters were scored in the first 2 min. The method proposed here is able to distinguish antidepressants from stimulants of motor activity using Swiss mice in the FST. This refinement should reduce the number of mice used in preclinical evaluation of antidepressants. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Sex and age differences in the impact of the forced swimming test on the levels of steroid hormones.

    Science.gov (United States)

    Martínez-Mota, Lucía; Ulloa, Rosa-Elena; Herrera-Pérez, Jaime; Chavira, Roberto; Fernández-Guasti, Alonso

    2011-10-24

    Compared with the adult disorder, depression in children exhibits differences in its neurobiology, particularly in the HPA axis regulation. The bases of such differences can be evaluated in animal models of depression. The objective of the present study was to determine age and sex differences of Wistar rats in the forced swimming test (FST). The influence of sex and age on corticosterone, estrogens and testosterone serum levels was also determined. Prepubertal rats showed immobility, swimming and climbing behaviors during the pre-test and test sessions. In addition, in the prepubertal animals, no sex differences were found during the pre-test and test sessions. Age comparisons indicated no differences in the female groups, however adult males exhibited more immobility and less swimming than young males, in both FST sessions. The young and female rats showed less immobility behavior and increased levels of estrogens after the FST. The present results indicate that the FST is an animal model suitable to evaluate depressive-like behaviors in prepubertal subjects and to explore behavioral changes related to neurodevelopment. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Forced swimming and imipramine modify plasma and brain amino acid concentrations in mice.

    Science.gov (United States)

    Murakami, Tatsuro; Yamane, Haruka; Tomonaga, Shozo; Furuse, Mitsuhiro

    2009-01-05

    The relationships between monoamine metabolism and forced swimming or antidepressants have been well studied, however information is lacking regarding amino acid metabolism under these conditions. Therefore, the aim of the present study was to investigate the effects of forced swimming and imipramine on amino acid concentrations in plasma, the cerebral cortex and the hypothalamus in mice. Forced swimming caused cerebral cortex concentrations of L-glutamine, L-alanine, and taurine to be increased, while imipramine treatment caused decreased concentrations of L-glutamate, L-alanine, L-tyrosine, L-methionine, and L-ornithine. In the hypothalamus, forced swimming decreased the concentration of L-serine while imipramine treatment caused increased concentration of beta-alanine. Forced swimming caused increased plasma concentration of taurine, while concentrations of L-serine, L-asparagine, L-glutamine and beta-alanine were decreased. Imipramine treatment caused increased plasma concentration of all amino acid, except for L-aspartate and taurine. In conclusion, forced swimming and imipramine treatment modify central and peripheral amino acid metabolism. These results may aid in the identification of amino acids that have antidepressant-like effects, or may help to refine the dosages of antidepressant drugs.

  6. Early remodeling of rat cardiac muscle induced by swimming training

    Directory of Open Access Journals (Sweden)

    Verzola R.M.M.

    2006-01-01

    Full Text Available The aim of the present investigation was to study the effect of acute swimming training with an anaerobic component on matrix metallopeptidase (MMP activity and myosin heavy chain gene expression in the rat myocardium. Animals (male Wistar rats, weighing approximately 180 g were trained for 6 h/day in 3 sessions of 2 h each for 1 to 5 consecutive days (N = 5 rats per group. Rats swam in basins 47 cm in diameter and 60 cm deep filled with water at 33 to 35ºC. After the training period a significant increase (P < 0.05 was observed in the heart weight normalized to body weight by about 22 and 35% in the groups that trained for 96 and 120 h, respectively. Blood lactate levels were significantly increased (P < 0.05 in all groups after all training sessions, confirming an anaerobic component. However, lactate levels decreased (P < 0.05 with days of training, suggesting that the animals became adapted to this protocol. Myosin heavy chain-ß gene expression, analyzed by real time PCR and normalized with GAPDH gene expression, showed a significant two-fold increase (P < 0.01 after 5 days of training. Zymography analysis of myocardium extracts indicated a single ~60-kDa activity band that was significantly increased (P < 0.05 after 72, 96, and 120 h, indicating an increased expression of MMP-2 and suggesting precocious remodeling. Furthermore, the presence of MMP-2 was confirmed by Western blot analysis, but not the presence of MMP-1 and MMP-3. Taken together, our results indicate that in these training conditions, the rat heart undergoes early biochemical and functional changes required for the adaptation to the new physiological condition by tissue remodeling.

  7. Swimming training induces liver mitochondrial adaptations to oxidative stress in rats submitted to repeated exhaustive swimming bouts.

    Directory of Open Access Journals (Sweden)

    Frederico D Lima

    Full Text Available BACKGROUND AND AIMS: Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts. METHODS: Wistar rats were divided into training (n = 14 and control (n = 14 groups. Training group performed a 6-week swimming training protocol. Subsets of training (n = 7 and control (n = 7 rats performed 3 repeated exhaustive swimming bouts with 72 h rest in between. Oxidative stress biomarkers, antioxidant activity, and mitochondria functionality were assessed. RESULTS: Trained group showed increased reduced glutathione (GSH content and reduced/oxidized (GSH/GSSG ratio, higher superoxide dismutase (MnSOD activity, and decreased lipid peroxidation in liver mitochondria. Aerobic training protected against exhaustive swimming ROS production herein characterized by decreased oxidative stress markers, higher antioxidant defenses, and increases in methyl-tetrazolium reduction and membrane potential. Trained group also presented higher time to exhaustion compared to control group. CONCLUSIONS: Swimming training induced positive adaptations in liver mitochondria of rats. Increased antioxidant defense after training coped well with exercise-produced ROS and liver mitochondria were less affected by exhaustive exercise. Therefore, liver mitochondria also adapt to exercise-induced ROS and may play an important role in exercise performance.

  8. Interactions between internal forces, body stiffness, and fluid environment in a neuromechanical model of lamprey swimming.

    Science.gov (United States)

    Tytell, Eric D; Hsu, Chia-Yu; Williams, Thelma L; Cohen, Avis H; Fauci, Lisa J

    2010-11-16

    Animal movements result from a complex balance of many different forces. Muscles produce force to move the body; the body has inertial, elastic, and damping properties that may aid or oppose the muscle force; and the environment produces reaction forces back on the body. The actual motion is an emergent property of these interactions. To examine the roles of body stiffness, muscle activation, and fluid environment for swimming animals, a computational model of a lamprey was developed. The model uses an immersed boundary framework that fully couples the Navier-Stokes equations of fluid dynamics with an actuated, elastic body model. This is the first model at a Reynolds number appropriate for a swimming fish that captures the complete fluid-structure interaction, in which the body deforms according to both internal muscular forces and external fluid forces. Results indicate that identical muscle activation patterns can produce different kinematics depending on body stiffness, and the optimal value of stiffness for maximum acceleration is different from that for maximum steady swimming speed. Additionally, negative muscle work, observed in many fishes, emerges at higher tail beat frequencies without sensory input and may contribute to energy efficiency. Swimming fishes that can tune their body stiffness by appropriately timed muscle contractions may therefore be able to optimize the passive dynamics of their bodies to maximize peak acceleration or swimming speed.

  9. Hepatoprotective Effects of Swimming Exercise against D-Galactose-Induced Senescence Rat Model

    Directory of Open Access Journals (Sweden)

    Chi-Chang Huang

    2013-01-01

    Full Text Available This study investigates whether a 12-week swimming exercise training can prevent liver damage or senescence associated biomarkers in an experimental aging model in rats. Twenty-three male Sprague-Dawley rats were divided into four groups: vehicle treatment with sedentary control (C, , aging induction with sedentary (A, , vehicle treatment with swimming exercise (SW, , and aging induction with swimming exercise (A + SW, . Rats in groups A and AS received intraperitoneal D-galactose injections (150 mg/kg/day for 12 weeks to induce aging. Rats in groups SW and A + SW were subjected to swimming exercise training for 12 weeks. Body weight, liver weight, epididymal fat mass, blood biochemistry, and liver pathology were performed at the end of the experiment. Hepatic senescence protein markers such as β-galactosidase, p53, and p21, as well as the inflammatory mediator, IL-6, were examined. The D-galactose-treated rats exhibited increases in AST and γ-GT plasma levels and β-galactosidase protein expression compared to the control group. Swimming exercise significantly reduced BW, epididymal fat mass, γ-GT activity, and p53, p21, and IL-6 protein levels compared to the aging group. These results suggest that a 12-week swimming exercise program suppresses senescence markers and downregulates inflammatory mediator in the liver tissues of D-galactose-induced aging rats.

  10. Effects of single and combined gabapentin use in elevated plus maze and forced swimming tests.

    Science.gov (United States)

    Kilic, Fatma Sultan; Ismailoglu, Sule; Kaygisiz, Bilgin; Oner, Setenay

    2014-10-01

    Gabapentin, a third-generation antiepileptic drug, is a structural analogue of γ-aminobutyric acid, which is an important mediator of central nervous system. There is clinical data indicating its effectiveness in the treatment of psychiatric illnesses such as bipolar disorder and anxiety disorders. We aimed to investigate the antidepressant and anxiolytic-like effects and mechanisms of gabapentin in rats. Female Spraque-Dawley rats weighing 250±20 g were used. A total of 13 groups were formed, each containing 8 rats: gabapentin (5, 10, 20, 40 mg/kg), amitriptyline (10 mg/kg), sertraline (5 mg/kg), diazepam (5 mg/kg), ketamine (10 mg/kg), gabapentin 20 mg/kg was also combined with amitriptyline (10 mg/kg), sertraline (5 mg/kg), diazepam (5 mg/kg) and ketamine (10 mg/kg). All the drugs were used intraperitoneally as single dose. Saline was administered to the control group. Elevated plus maze and forced swimming tests were used as experimental models of anxiety and depression, respectively. It was observed that gabapentin showed an anxiolytic-like and antidepressant-like effect in all doses in rats. Its antidepressant effect was found to be the same as the antidepressant effects of amitriptyline and sertraline. There was no change in the antidepressant effect when gabapentin was combined with amitriptyline and ketamine, but there was an increase when combined with sertraline and diazepam. Gabapentin and amitriptyline showed similar anxiolytic effect, whereas ketamine and diazepam had more potent anxiolytic effect compared with them. These data suggest that gabapentin may possess antidepressant- and anxiolytic-like effects.

  11. Effect of swimming exercise on three-dimensional trabecular bone microarchitecture in ovariectomized rats.

    Science.gov (United States)

    Ju, Yong-In; Sone, Teruki; Ohnaru, Kazuhiro; Tanaka, Kensuke; Fukunaga, Masao

    2015-11-01

    Swimming is generally considered ineffective for increasing bone mass in humans, at least compared with weight-bearing sports. However, swimming exercise has sometimes been shown to have a strong positive effect on bone mass in small animals. This study investigated the effects of swimming on bone mass, strength, and microarchitecture in ovariectomized (OVX) rats. OVX or sham operations were performed on 18-wk-old female Fisher 344 rats. Rats were randomly divided into four groups: sham sedentary (Sham-CON), sham swimming exercised (Sham-SWI), OVX sedentary (OVX-CON), and OVX swimming exercised (OVX-SWI). Rats in exercise groups performed swimming in a water bath for 60 min/day, 5 days/wk, for 12 wk. Bone mineral density (BMD) in right femurs was analyzed using dual-energy X-ray absorptiometry. Three-dimensional trabecular architecture at the distal femoral metaphysis was analyzed using microcomputed tomography (μCT). Geometrical properties of diaphyseal cortical bone were evaluated in the midfemoral region using μCT. The biomechanical properties of femurs were analyzed using three-point bending. Femoral BMD was significantly decreased following ovariectomy. This change was suppressed by swimming. Trabecular bone thickness, number, and connectivity were decreased by ovariectomy, whereas structure model index (i.e., ratio of rod-like to plate-like trabeculae) increased. These changes were also suppressed by swimming exercise. Femurs displayed greater cortical width and maximum load in SWI groups than in CON groups. Together, these results demonstrate that swimming exercise drastically alleviated both OVX-induced decreases in bone mass and mechanical strength and the deterioration of trabecular microarchitecture in rat models of osteoporosis. Copyright © 2015 the American Physiological Society.

  12. Critical force during tethered swimming for the evaluation of aerobic capacity and prediction of performances in freestyle swimming

    Directory of Open Access Journals (Sweden)

    Marcelo Papoti

    2010-01-01

    Full Text Available The present study investigated the relationship of critical force (Fcrit with lactate threshold (LLNA and the intensity corresponding to VO2max (iVO2max in tethered swimming (TS, and their correlation with maximal performance in 400-m (V400 and 30-min (VT30 freestyle swimming (FS. Seven swimmers were submitted to a TS incremental test for the determination of LLNA and iVO2max. For the determination of Fcrit, the swimmers performed four exercises to exhaustion at intensities (F corresponding to 87%, 104%, 118% and 134% of iVO2max for the calculation of time limits (Tlim. Fcrit corresponded to the linear coefficient of the ratio between F and 1/tlim. The maximal performance in FS corresponded to the mean velocity obtained during maximal exercise of 400-m and 30-min crawl swimming. Fcrit (51.97 ± 4.02 N was significantly lower than iVO2max (60.21 ± 8.73 N but not than LLNA (45.89 ± 8.73. Fcrit was significantly correlated with iVO2max (0.97, LLNA (0.88, V400 (0.85, and VT30 (0.86. These data suggest that Fcrit can be used for the determination of aerobic capacity, prescription of a TS training program, and prediction of performance in FS.

  13. Histomorphometric analysis of the response of rat skeletal muscle to swimming, immobilization and rehabilitation

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    C.C.F. Nascimento

    2008-09-01

    Full Text Available The objective of the present study was to determine to what extent, if any, swimming training applied before immobilization in a cast interferes with the rehabilitation process in rat muscles. Female Wistar rats, mean weight 260.52 ± 16.26 g, were divided into 4 groups of 6 rats each: control, 6 weeks under baseline conditions; trained, swimming training for 6 weeks; trained-immobilized, swimming training for 6 weeks and then immobilized for 1 week; trained-immobilized-rehabilitated, swimming training for 6 weeks, immobilized for 1 week and then remobilized with swimming for 2 weeks. The animals were then sacrificed and the soleus and tibialis anterior muscles were dissected, frozen in liquid nitrogen and processed histochemically (H&E and mATPase. Data were analyzed statistically by the mixed effects linear model (P < 0.05. Cytoarchitectural changes such as degenerative characteristics in the immobilized group and regenerative characteristics such as centralized nucleus, fiber size variation and cell fragmentation in the groups submitted to swimming were more significant in the soleus muscle. The diameters of the lesser soleus type 1 and type 2A fibers were significantly reduced in the trained-immobilized group compared to the trained group (P < 0.001. In the tibialis anterior, there was an increase in the number of type 2B fibers and a reduction in type 2A fibers when trained-immobilized rats were compared to trained rats (P < 0.001. In trained-immobilized-rehabilitated rats, there was a reduction in type 2B fibers and an increase in type 2A fibers compared to trained-immobilized rats (P < 0.009. We concluded that swimming training did not minimize the deleterious effects of immobilization on the muscles studied and that remobilization did not favor tissue re-adaptation.

  14. Impact of maternal melatonin suppression on forced swim and tail suspension behavioral despair tests in adult offspring.

    Science.gov (United States)

    Voiculescu, S E; Rosca, A E; Zeca, V; Zagrean, L; Zagrean, A M

    2015-01-01

    Melatonin is an essential hormone, which regulates circadian rhythms and has antioxidative and anticarcinogenic effects. As melatonin secretion is suppressed by light, this effect was examined on the offspring of the Wistar rat females exposed to continuous light (500 lux) during the second half of the pregnancy (day 12 to 21). Control rats were kept under a 12:12 light-dark cycle. The resulted male offspring have been behaviorally assessed for depression after postnatal day 60 by using Forced Swim Test (FST) and Tail Suspension Test (TST). Animals resulted from the melatonin deprived pregnancies have developed an abnormal response in the TST, but a normal FST behavior. Also, TST active movement was different in the melatonin suppression group compared to the control group. These findings suggest that intrauterine melatonin deprivation might be linked to the depressive like behavior in adult male offspring.

  15. Stress-induced anhedonia in mice is associated with deficits in forced swimming and exploration.

    Science.gov (United States)

    Strekalova, Tatyana; Spanagel, Rainer; Bartsch, Dusan; Henn, Fritz A; Gass, Peter

    2004-11-01

    In order to develop a model for a depression-like syndrome in mice, we subjected male C57BL/6 mice to a 4-week-long chronic stress procedure, consisting of rat exposure, restraint stress, and tail suspension. This protocol resulted in a strong decrease in sucrose preference, a putative indicator of anhedonia in rodents. Interestingly, predisposition for stress-induced anhedonia was indicated by submissive behavior in a resident-intruder test. In contrast, most mice with nonsubmissive behavior did not develop a decrease in sucrose preference and were regarded as nonanhedonic. These animals were used as an internal control for stress-induced behavioral features not associated with the anhedonic state, since they were exposed to the same stressors as the anhedonic mice. Using a battery of behavioral tests after termination of the stress procedure, we found that anhedonia, but not chronic stress per se, is associated with key analogues of depressive symptoms, such as increased floating during forced swimming and decreased exploration of novelty. On the other hand, increased anxiety, altered locomotor activity, and loss of body weight were consequences of chronic stress, which occurred independently from anhedonia. Thus, behavioral correlates of stress-induced anhedonia and of chronic stress alone can be separated in the present model.

  16. Swimming intervention mitigates HFD-induced obesity of rats through PGC-1α-irisin pathway.

    Science.gov (United States)

    Yang, X-Q; Yuan, H; Li, J; Fan, J-J; Jia, S-H; Kou, X-J; Chen, N

    2016-05-01

    Irisin, a newly discovered myokine, can drive the browning of white adipocytes to control body weight or mitigate obesity progression through regulating energy metabolism. However, the underlying mechanisms or specific signal pathways of exercise-induced irisin on the management of obesity are still unclear. Totally 30 rats were subjected to high fat diet (HFD) feeding for 8 weeks to establish the rat model with obesity successfully. HFD-induced obese model rats were provided with 8 weeks swimming intervention at moderate intensity for exploring the treatment of obesity through exercise intervention. In addition, another 15 rats were subjected to HFD feeding coupled with total 16 weeks swimming intervention at a moderate intensity from the beginning of the experiment, which was used for exploring the prevention of obesity through exercise intervention. Blood and gastrocnemius samples were harvested from obese rats after swimming intervention to explore its specific signal pathways through ELISA analysis and Western blotting. HFD feeding of rats for 8 weeks could lead to the obesity due to the disorders of lipid metabolism. Totally 8 weeks swimming intervention at moderate intensity for rats with obesity could obviously alleviate the progression of obesity and 16 weeks swimming intervention from the beginning of the experiment could significantly inhibit the development of obesity. Meanwhile, swimming intervention could result in an increased phosphorylation of AMPK and up-regulation of irisin and PGC-1α as the biomarkers of energy metabolism. Exercise intervention can activate PGC-1α-dependent irisin to induce the browning of white adipocytes, thus inhibiting or alleviating the occurrence and development of obesity.

  17. Performance Level Differences in Swimming: A Meta-Analysis of Passive Drag Force

    Science.gov (United States)

    Havriluk, Rod

    2005-01-01

    The streamline is a basic position for competitive swimming starts mid turns and has been used in many studies on resistive forces. However, there is a wide yahweh, of theoretical interpretations in these studies, leading to diverse and questionable conclusions. The purpose of this study was to determine performance level differences in the…

  18. Antidepressant-like effects of Perilla frutescens seed oil during a forced swimming test.

    Science.gov (United States)

    Lee, Hsiu-Chuan; Ko, Hsiang-Kai; Huang, Brian E T-G; Chu, Yan-Hwa; Huang, Shih-Yi

    2014-05-01

    Unipolar depressive disorder may become one of the major leading causes of disease burden by 2030 according to the World Health Organization (WHO). Thus, the discovery of antidepressive foods is attractive and could have considerable impacts worldwide. We investigated the antidepressant-like effects of Perilla frutescens seed oil on adult male rats subjected to a forced swimming test (FST). Forty Sprague-Dawley rats were housed and fed various diets, including soybean oil-rich, eicosapentaenoic acid (EPA)-rich, and P. frutescens seed oil-rich diets for 6 weeks. After the dietary intervention, animals were tested using an FST and were sacrificed after the test. We analyzed the fatty acid profiles of red blood cells (RBCs) and the brain prefrontal cortex (PFC). Levels of brain-derived neurotrophic factor (BDNF), serotonin, and dopamine in the PFC were also determined. After the FST, the imipramine, EPA-rich, and P. frutescens seed oil-rich groups showed significant shorter immobility time and longer struggling time than the control group (p < 0.05). Levels of BDNF in the P. frutescens seed oil-rich group and levels of serotonin in the EPA-rich group were significantly (p < 0.05) higher than those of the control group. Moreover, the BDNF concentration in the PFC was significantly positively correlated with the struggling time. However, there were no significant differences in dopamine levels between the intervention groups and the control group. In conclusion, a P. frutescens seed oil-rich diet exhibited antidepressant-like properties through modulation of fatty acid profiles and BDNF expression in the brain during an FST.

  19. Activation of Erk and JNK MAPK pathways by acute swim stress in rat brain regions

    Directory of Open Access Journals (Sweden)

    Salvadore Christopher

    2004-09-01

    Full Text Available Abstract Background The mitogen-activated protein kinases (MAPKs have been shown to participate in a wide array of cellular functions. A role for some MAPKs (e.g., extracellular signal-regulated kinase, Erk1/2 has been documented in response to certain physiological stimuli, such as ischemia, visceral pain and electroconvulsive shock. We recently demonstrated that restraint stress activates the Erk MAPK pathway, but not c-Jun-N-terminal kinase/stress-activated protein kinase (JNK/SAPK or p38MAPK, in several rat brain regions. In the present study, we investigated the effects of a different stressor, acute forced swim stress, on the phosphorylation (P state of these MAPKs in the hippocampus, neocortex, prefrontal cortex, amygdala and striatum. In addition, effects on the phosphorylation state of the upstream activators of the MAPKs, their respective MAPK kinases (MAPKKs; P-MEK1/2, P-MKK4 and P-MKK3/6, were determined. Finally, because the Erk pathway can activate c-AMP response element (CRE binding (CREB protein, and swim stress has recently been reported to enhance CREB phosphorylation, changes in P-CREB were also examined. Results A single 15 min session of forced swimming increased P-Erk2 levels 2–3-fold in the neocortex, prefrontal cortex and striatum, but not in the hippocampus or amygdala. P-JNK levels (P-JNK1 and/or P-JNK2/3 were increased in all brain regions about 2–5-fold, whereas P-p38MAPK levels remained essentially unchanged. Surprisingly, levels of the phosphorylated MAPKKs, P-MEK1/2 and P-MKK4 (activators of the Erk and JNK pathways, respectively were increased in all five brain regions, and much more dramatically (P-MEK1/2, 4.5 to > 100-fold; P-MKK4, 12 to ~300-fold. Consistent with the lack of forced swim on phosphorylation of p38MAPK, there appeared to be no change in levels of its activator, P-MKK3/6. P-CREB was increased in all but cortical (prefrontal, neocortex areas. Conclusions Swim stress specifically and markedly

  20. Estudio preliminar de la expresión proteómica cerebral de la región hipocampal de ratas expuestas a diferentes niveles de estrés inducido por el nado forzado Preliminary study of cerebral proteomics expression of hippocampal region from rats exposed to different stress levels induced by forced swimming

    Directory of Open Access Journals (Sweden)

    Guerrero Nasser

    2012-04-01

    stress to which an animal is exposed, and hippocampal protein expression. Objective: to evaluate the differential hippocampal protein expression in Wistar-UIS rats, exposed to dissimilar levels of stress induced by forced swimming. Materials and methods: we used 30 rats randomly assigned to 3 groups according to duration of exposure to forced swimming as stressor stimulus (0, 5 and 15 minutes. 24 hours after the dorsal hippocampi were removed and two-dimensional electrophoresis was performed to the extracted proteins. Then, image processing of the gels obtained was performed using the PDQuest 2D software. Those proteins in which intensities were detected associated with the stimulus-exposure times were presumptively identified using Export Protein Analysis System (EXPASY a bioinformatics database. Results: according to the bioinformatic and proteomic analyses we identified 60 proteins, 38 of which were common to both left and right hippocampi, 13 were found only in the right hippocampi and 9 in the left. Conclusion: dose-dependent decreasing rate differences in protein expression between the left and right hippocampus were found after animals were subjected to different levels of stress induced by forced swimming test. Salud UIS 2012; 44 (1: 17-27

  1. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi).

    Science.gov (United States)

    Palstra, Arjan P; Mes, Daan; Kusters, Kasper; Roques, Jonathan A C; Flik, Gert; Kloet, Kees; Blonk, Robbert J W

    2014-01-01

    Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (U opt in m s(-1) or body lengths s(-1), BL s(-1)) were assessed and then applied to determine the effects of long-term forced and sustained swimming at U opt on growth performance of juvenile yellowtail kingfish. U opt was quantified in Blazka-type swim-tunnels for 145, 206, and 311 mm juveniles resulting in values of: (1) 0.70 m s(-1) or 4.83 BL s(-1), (2) 0.82 m s(-1) or 3.25 BL s(-1), and (3) 0.85 m s(-1) or 2.73 BL s(-1). Combined with literature data from larger fish, a relation of U opt (BL s(-1)) = 234.07(BL)(-0.779) (R (2) = 0.9909) was established for this species. Yellowtail kingfish, either forced to perform sustained swimming exercise at an optimal speed of 2.46 BL s(-1) ("swimmers") or allowed to perform spontaneous activity at low water flow ("resters") in a newly designed 3600 L oval flume (with flow created by an impeller driven by an electric motor), were then compared. At the start of the experiment, ten fish were sampled representing the initial condition. After 18 days, swimmers (n = 23) showed a 92% greater increase in BL and 46% greater increase in BW as compared to resters (n = 23). As both groups were fed equal rations, feed conversion ratio (FCR) for swimmers was 1.21 vs. 1.74 for resters. Doppler ultrasound imaging showed a statistically significant higher blood flow (31%) in the ventral aorta of swimmers vs. resters (44 ± 3 vs. 34 ± 3 mL min(-1), respectively, under anesthesia). Thus, growth performance can be rapidly improved by optimal swimming, without larger feed investments.

  2. Effect of Polysaccharide from Cordyceps militaris (Ascomycetes) on Physical Fatigue Induced by Forced Swimming.

    Science.gov (United States)

    Xu, Yan-Feng

    2016-01-01

    Cordyceps militaris is the one of the most important medicinal mushrooms, widely used in East Asian countries. Polysaccharide is considered to be the principal active component in C. militaris and has a wide range of biological and pharmacological properties. This study was undertaken to investigate the effect of polysaccharide from C. militaris (PCM) on physical fatigue induced in animals through a forced swimming test. The mice were divided into 4 groups receiving 28 days' treatment with drinking water (exercise control) or low-, medium-, and high-dose PCM (40, 80, and 160 mg/kg/day, respectively). After 28 days, the mice were subjected to the forced swimming test; the exhaustive swimming time was measured and fatigue-related biochemical parameters, including serum lactic acid, urea nitrogen, creatine kinase, alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, glutathi- one peroxidase, catalase, malondialdehyde, liver glycogen, and muscle glycogen, were analyzed. The results showed that PCM could significantly prolong the exhaustive swimming time of mice; decrease concentrations of serum lactic acid, urea nitrogen, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and malondialdehyde; and increase liver and muscle glycogen contents and the concentrations of serum superoxide dismutase, glutathione per- oxidase, and catalase. The data suggest that PCM has an antifatigue effect, and it might become a new functional food or medicine for fatigue resistance.

  3. Pregnancy swimming causes short- and long-term neuroprotection against hypoxia-ischemia in very immature rats.

    Science.gov (United States)

    Sanches, Eduardo Farias; Durán-Carabali, Luz Elena; Tosta, Andrea; Nicola, Fabrício; Schmitz, Felipe; Rodrigues, André; Siebert, Cassiana; Wyse, Angela; Netto, Carlos

    2017-09-01

    BackgroundHypoxia-ischemia (HI) is a major cause of neurological damage in preterm newborn. Swimming during pregnancy alters the offspring's brain development. We tested the effects of swimming during pregnancy in the very immature rat brain.MethodsFemale Wistar rats (n=12) were assigned to the sedentary (SE, n=6) or the swimming (SW, n=6) group. From gestational day 0 (GD0) to GD21 the rats in the SW group were made to swim for 20 min/day. HI on postnatal day (PND) 3 rats caused sensorimotor and cognitive impairments. Animals were distributed into SE sham (SESH), sedentary HIP3 (SEHI), swimming sham (SWSH), and swimming HIP3 (SWHI) groups. At PND4 and PND5, Na + /K + -ATPase activity and brain-derived neurotrophic factor (BDNF) levels were assessed. During lactation and adulthood, neurological reflexes, sensorimotor, anxiety-related, and cognitive evaluations were made, followed by histological assessment at PND60.ResultsAt early stages, swimming caused an increase in hippocampal BDNF levels and in the maintenance of Na + /K + -ATPase function in the SWHI group. The SWHI group showed smaller lesions and the preservation of white matter tracts. SEHI animals showed a delay in reflex maturation, which was reverted in the SWHI group. HIP3 induced spatial memory deficits and hypomyelination in SEHI rats, which was reverted in the SWHI group.ConclusionSwimming during pregnancy neuroprotected the brains against HI in very immature neonatal rats.

  4. Effects of short-term swimming exercise on bone mineral density, geometry, and microstructural properties in sham and ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Foong Kiew Ooi

    2014-12-01

    Full Text Available Little information exists about the effects of swimming exercise on bone health in ovariectomized animals with estrogen deficiency, which resembles the postmenopausal state and age-related bone loss in humans. This study investigated the effects of swimming exercise on tibia and femur bone mineral density (BMD, geometry, and microstructure in sham and ovariectomized rats. Forty 3-month-old female rats were divided into four groups: sham operated-sedentary control (Sham-control, sham operated with swimming exercise group (Sham-Swim, ovariectomy-sedentary control (OVx-control, and ovariectomy and swimming exercise (OVx-Swim groups. Swimming sessions were performed by the rats 90 minutes/day for 5 days/week for a total of 8 weeks. At the end of the study, tibial and femoral proximal volumetric total BMD, midshaft cortical volumetric BMD, cross-sectional area, and cross-sectional moment of inertia (MOI, and bone microstructural properties were measured for comparison. Data were analyzed using one-way analysis of variance (ANOVA. The Sham-Swim group exhibited significantly (p < 0.05; one-way ANOVA greater values in bone geometry parameters, that is, tibial midshaft cortical area and MOI compared to the Sham-control group. However, no significant differences were observed in these parameters between the Ovx-Swim and Ovx-control groups. There were no significant differences in femoral BMD between the Sham-Swim and Sham-control groups. Nevertheless, the Ovx-Swim group elicited significantly (p < 0.05; one-way ANOVA higher femoral proximal total BMD and improved bone microstructure compared to the Ovx-Sham group. In conclusion, the positive effects of swimming on bone properties in the ovariectomized rats in the present study may suggest that swimming as a non- or low-weight-bearing exercise may be beneficial for enhancing bone health in the postmenopausal population.

  5. Psychostimulants and forced swim stress interaction: how activation of the hypothalamic-pituitary-adrenal axis and stress-induced hyperglycemia are affected.

    Science.gov (United States)

    Gagliano, Humberto; Ortega-Sanchez, Juan Antonio; Nadal, Roser; Armario, Antonio

    2017-10-01

    We recently reported that simultaneous exposure to amphetamine and various stressors resulted in reduced hypothalamic-pituitary-adrenal (HPA) and glycemic responses to the stressors. Since this is a new and relevant phenomenon, we wanted to further explore this interaction. This study aims (i) to characterize the effect of various doses of amphetamine on the physiological response to a predominantly emotional stressor (forced swim) when the drug was given immediately before stress; (ii) to study if an interaction appears when the drug was given 30 min or 7 days before swim; and (iii) to know whether cocaine causes similar effects when given just before stress. Adult male rats were used and plasma levels of ACTH, corticosterone, and glucose were the outcomes. Amphetamine caused a dose-dependent activation of the HPA axis, but all doses reduced HPA and glycemic responses to swim when given just before the stressor. Importantly, during the post-swim period, the stressor potently inhibited the ACTH response to amphetamine, demonstrating mutual inhibition between the two stimuli. The highest dose of amphetamine also reduced the response to swim when given 30 min before stress, whereas it caused HPA sensitization when given 7 days before. Cocaine also reduced stress-induced HPA activation when given just before swim. The present results demonstrate a negative synergy between psychostimulants (amphetamine and cocaine) and stress regarding HPA and glucose responses when rats were exposed simultaneously to both stimuli. The inhibitory effect of amphetamine is also observed when given shortly before stress, but not some days before.

  6. Swimming exercise attenuates psychological dependence and voluntary methamphetamine consumption in methamphet- amine withdrawn rats

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    Fatemeh Damghani

    2016-06-01

    Conclusion: This study showed that regular swimming exercise reduced voluntary METH consumption in animal models of craving by reducing anxiety, OCD, and depression in the METH-withdrawn rats. Thus, physical training may be ameliorating some of the withdrawal behavioral consequences of METH.

  7. METHODS FOR MEASUREMENT OF ENERGY-EXPENDITURE AND SUBSTRATE CONCENTRATIONS IN SWIMMING RATS

    NARCIS (Netherlands)

    BENTHEM, L; BOLHUIS, JW; VANDERLEEST, J; STEFFENS, AB; ZOCK, JP; ZIJLSTRA, WG

    A measuring system is described for the determination of oxygen consumption (V-O2) and carbon dioxide production (V-CO2) in swimming rats. V-O2 and V-CO2 were measured by means of an O-2-analyzer (Ametek S3A) and a mass spectrometer (Balzers QMG 511), respectively, combined with a gas flow meter.

  8. Forced swimming-induced oxytocin release into blood and brain: Effects of adrenalectomy and corticosterone treatment.

    Science.gov (United States)

    Torner, Luz; Plotsky, Paul M; Neumann, Inga D; de Jong, Trynke R

    2017-03-01

    The oxytocin (OXT) system is functionally linked to the HPA axis in a reciprocal and complex manner. Certain stressors are known to cause the simultaneous release of OXT and adrenocorticotrophic hormone (ACTH) followed by corticosterone (CORT). Furthermore, brain OXT attenuates ACTH and CORT responses. Although there are some indications of CORT influencing OXT neurotransmission, specific effects of CORT on neurohypophyseal or intra-hypothalamic release of OXT have not been studied in detail. In the present set of experiments, adult male rats were adrenalectomized (ADX) or sham-operated and fitted with a jugular vein catheter and/or microdialysis probe targeting the hypothalamic paraventricular nucleus (PVN). Blood samples and dialysates were collected before and after forced swimming (FS) and analyzed for CORT, ACTH and AVP concentrations (in plasma) and OXT concentrations (in plasma and dialysates). Experimental treatments included acute infusion of CORT (70 or 175μg/kg i.v.) 5min prior to FS, or subcutaneous placement of 40% CORT pellets resulting in stable CORT levels in the normal basal range. Although ADX did not alter basal OXT concentrations either in plasma or in microdialysates from the PVN, it did cause an exaggerated peripheral secretion of OXT and a blunted intra-PVN release of OXT in response to FS. CORT pellets did not influence either of these ADX-induced effects, while acute infusion of 175μg/kg CORT rescued the stress-induced rise in OXT release within the PVN and modestly increased peripheral OXT secretion. In conclusion, these results indicate that CORT regulates both peripheral and intracerebral OXT release, but in an independent manner. Whereas the peripheral secretion of OXT occurs simultaneously to HPA axis activation in response to FS and is modestly influenced by CORT, HPA axis activation and circulating CORT strongly contribute to the stress-induced stimulation of OXT release within the PVN. Copyright © 2016 Elsevier Ltd. All rights

  9. Omega-3 Fatty Acid Deficient Male Rats Exhibit Abnormal Behavioral Activation in the Forced Swim Test Following Chronic Fluoxetine Treatment: Association with Altered 5-HT1A and Alpha2A Adrenergic Receptor Expression

    OpenAIRE

    Able, Jessica A.; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K.

    2013-01-01

    Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n=34) or without (DEF, n=30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n=14) and DEF (n=12) rats were ...

  10. Using Magnetic Forces to Probe the Gravi-response of Swimming Paramecium

    Science.gov (United States)

    Guevorkian, Karine; Valles, James M., Jr.

    2004-03-01

    Paramecium Caudatum, a single celled ciliate, alters its swimming behavior when subjected to different gravity environments (e.g. centrifugation and micro-gravity). To dissect the mechanisms behind this gravi-response and that of other biological systems, we are developing the use of magnetic body forces as a means of creating a rapidly tunable, simulated variable gravity environment. Since biological materials are weakly diamagnetic, we must subject them to intense inhomogeneous magnetic fields with characteristic field-field gradient products on the order of 16 T^2/cm. We will describe experiments on Paramecium Caudatum in which we adjust their net buoyancy with magnetic forces and measure the resulting changes in their swimming behavior.

  11. [Unpredictable chronic mild stress effects on antidepressants activities in forced swim test].

    Science.gov (United States)

    Kudryashov, N V; Kalinina, T S; Voronina, T A

    2015-02-01

    The experiments has been designed to study unpredictable chronic mild stress effect on anti-depressive activities of amitriptyline (10 mg/kg) and fluoxetine (20 mg/kg) in forced swim test in male outbred mice. It is shown that acute treatment with fluoxetine does not produce any antidepressant effects in mice following stress of 14 days while the sub-chronic injections of fluoxetine result in more deep depressive-like behavior. In 28 daily stressed mice, antidepressant effect of fluoxetine is observed independently of the injection rates. Amitriptyline demonstrates the antidepressant activity regardless of the duration of stress or administration scheduling, but at the same time the severity of anti-immobilization effect of amitriptyline in stressed mice is weaker in compare to non-stressed trails. Thus, the injection rates and duration of unpredictable mild chronic stress are the parameters that determine the efficiency of antidepressants in the mouse forced swimming test.

  12. Coping with the Forced Swim Stressor: Towards Understanding an Adaptive Mechanism.

    Science.gov (United States)

    de Kloet, E R; Molendijk, M L

    2016-01-01

    In the forced swim test (FST) rodents progressively show increased episodes of immobility if immersed in a beaker with water from where escape is not possible. In this test, a compound qualifies as a potential antidepressant if it prevents or delays the transition to this passive (energy conserving) behavioural style. In the past decade however the switch from active to passive "coping" was used increasingly to describe the phenotype of an animal that has been exposed to a stressful history and/or genetic modification. A PubMed analysis revealed that in a rapidly increasing number of papers (currently more than 2,000) stress-related immobility in the FST is labeled as a depression-like phenotype. In this contribution we will examine the different phases of information processing during coping with the forced swim stressor. For this purpose we focus on the action of corticosterone that is mediated by the closely related mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) in the limbic brain. The evidence available suggests a model in which we propose that the limbic MR-mediated response selection operates in complementary fashion with dopaminergic accumbens/prefrontal executive functions to regulate the transition between active and passive coping styles. Upon rescue from the beaker the preferred, mostly passive, coping style is stored in the memory via a GR-dependent action in the hippocampal dentate gyrus. It is concluded that the rodent's behavioural response to a forced swim stressor does not reflect depression. Rather the forced swim experience provides a unique paradigm to investigate the mechanistic underpinning of stress coping and adaptation.

  13. Embryo developmental capacity of oocytes fertilised by sperm of mouse exposed to forced swimming stress

    International Nuclear Information System (INIS)

    Ghasem, S.; Majid, J.; Shiva, R.

    2013-01-01

    Objective: To assess developmental capacity of fertilised oocytes by sperm of mouse exposed to forced swimming stress. Methods: The experimental study was conducted at the Physiology Research Center of Ahvaz Jundishapur University of Medical Sciences, from August 2011 to January 2012. It comprised 20 adult male and 10 female mice. The male mice were randomly divided into two equal groups (n=10): control and experimental. Animals of the experimental group were submitted to forced swimming stress. All male mice were euthanised and the cauda epididymis removed before contents were squeezed out. A pre-incubated capacitated sperm was gently added to the freshly collected ova of the two groups of study. The combined sperm-oocyte suspension was incubated for 4-6 hours under a condition of 5% Carbon dioxide and 37 degree C temperature. The ova were then washed through several changes of medium and finally incubated. Fertilisation was assessed by recording the number of 1-cell embryos 4-6 hours after insemination. The 1-cell embryos were allowed to further develop in vitro for about 120 hours. Development of embryos everyday and during 5 days of culture was observed by using inverted microscope. SPSS 13.0.1 was used for statistical analysis. Results: The percentage of oocytes fertilised was 75:96 (78.12+-4.8%) and 50:10 (49.5+-3.9%) in the control and experimental groups, respectively. The difference was significant (p 0.05) between the two groups in terms of speed and developmental capacity of blastocysts. Conclusions: Fertilisation capacity of male mice affected by forced swimming stress and also the developmental capacity of oocyte fertilised by sperm of mouse exposed to forced swimming stress decreased. (author)

  14. Embryo developmental capacity of oocytes fertilised by sperm of mouse exposed to forced swimming stress.

    Science.gov (United States)

    Ghasem, Saki; Majid, Jasemi; Shiva, Razi

    2013-07-01

    To assess developmental capacity of fertilised oocytes by sperm of mouse exposed to forced swimming stress. The experimental study was conducted at the Physiology Research Center of Ahvaz Jundishapur University of Medical Sciences, from August 2011 to January 2012. It comprised 20 adult male and 10 female mice. The male mice were randomly divided into two equal groups (n=10): control and experimental. Animals of the experimental group were submitted to forced swimming stress. All male mice were euthanised and the cauda epididymis removed before contents were squeezed out. A pre-incubated capacitated sperm was gently added to the freshly collected ova of the two groups of study. The combined sperm-oocyte suspension was incubated for 4-6 hours under a condition of 5% Carbon dioxide and 37 degreeC temperature. The ova were then washed through several changes of medium and finally incubated. Fertilisation was assessed by recording the number of 1-cell embryos 4-6 hours after insemination. The 1-cell embryos were allowed to further develop in vitro for about 120 hours. Development of embryos everyday and during 5 days of culture was observed by using inverted microscope. SPSS 13.0.1 was used for statistical analysis. The percentage of oocytes fertilised was 75:96 (78.12+/-4.8%) and 50:10 (49.5+/-3.9%) in the control and experimental groups, respectively. The difference was significant (p 0.05) between the two groups in terms of speed and developmental capacity of blastocysts. Fertilisation capacity of male mice affected by forced swimming stress and also the developmental capacity of oocyte fertilised by sperm of mouse exposed to forced swimming stress decreased.

  15. Inhibition of Progesterone Metabolism Mimics the Effect of Progesterone Withdrawal on Forced Swim Test Immobility

    OpenAIRE

    Beckley, Ethan H.; Finn, Deborah A.

    2007-01-01

    Withdrawal from high levels of progesterone in rodents has been proposed as a model for premenstrual syndrome or postpartum depression. Forced swim test (FST) immobility, used to model depression, was assessed in intact female DBA/2J mice following progesterone withdrawal (PWD) or treatment with the 5α-reductase inhibitor finasteride. Following 5 daily progesterone injections (5 mg/kg IP) FST immobility increased only in mice withdrawn for 3 days (p < .05). In another experiment, 3 days of PW...

  16. Exposure to Forced Swim Stress Alters Local Circuit Activity and Plasticity in the Dentate Gyrus of the Hippocampus

    Directory of Open Access Journals (Sweden)

    Mouna Maroun

    2008-02-01

    Full Text Available Studies have shown that, depending on its severity and context, stress can affect neural plasticity. Most related studies focused on synaptic plasticity and long-term potentiation (LTP of principle cells. However, evidence suggests that following high-frequency stimulation, which induces LTP in principal cells, modifications also take place at the level of complex interactions with interneurons within the dentate gyrus, that is, at the local circuit level. So far, the possible effects of stress on local circuit activity and plasticity were not studied. Therefore, we set out to examine the possible alterations in local circuit activity and plasticity following exposure to stress. Local circuit activity and plasticity were measured by using frequency dependant inhibition (FDI and commissural modulation protocols following exposure to a 15 minute-forced swim trial. Exposure to stress did not alter FDI. The application of theta-burst stimulation (TBS reduced FDI in both control and stressed rats, but this type of plasticity was greater in stressed rats. Commissural-induced inhibition was significantly higher in stressed rats both before and after applying theta-burst stimulation. These findings indicate that the exposure to acute stress affects aspects of local circuit activity and plasticity in the dentate gyrus. It is possible that these alterations underlie some of the behavioral consequences of the stress experience.

  17. Exposure to Forced Swim Stress Alters Local Circuit Activity and Plasticity in the Dentate Gyrus of the Hippocampus

    Science.gov (United States)

    Yarom, Orli; Maroun, Mouna; Richter-Levin, Gal

    2008-01-01

    Studies have shown that, depending on its severity and context, stress can affect neural plasticity. Most related studies focused on synaptic plasticity and long-term potentiation (LTP) of principle cells. However, evidence suggests that following high-frequency stimulation, which induces LTP in principal cells, modifications also take place at the level of complex interactions with interneurons within the dentate gyrus, that is, at the local circuit level. So far, the possible effects of stress on local circuit activity and plasticity were not studied. Therefore, we set out to examine the possible alterations in local circuit activity and plasticity following exposure to stress. Local circuit activity and plasticity were measured by using frequency dependant inhibition (FDI) and commissural modulation protocols following exposure to a 15 minute-forced swim trial. Exposure to stress did not alter FDI. The application of theta-burst stimulation (TBS) reduced FDI in both control and stressed rats, but this type of plasticity was greater in stressed rats. Commissural-induced inhibition was significantly higher in stressed rats both before and after applying theta-burst stimulation. These findings indicate that the exposure to acute stress affects aspects of local circuit activity and plasticity in the dentate gyrus. It is possible that these alterations underlie some of the behavioral consequences of the stress experience. PMID:18301720

  18. Swimming immobility time decreased in prenatally x-irradiated microcephalic rats

    International Nuclear Information System (INIS)

    Seo, Misako; Kiyono, Sigehiro; Shibagaki, Masamitsu

    1986-01-01

    Pregnant rats were X-irradiated (150 R) on gestation day 17, and the offspring were weaned at 21 days of age. After recording the spontaneous activity for one hour using Animex apparatus at 40 days of age, male offspring were tested for swimming immobility time on two consecutive days at 62 days of age. All X-irradiated pups were microcephalic, and their mean total brain weight was 78.5 % of the control group. Although no difference was found in spontaneous activity between the two groups, swimming immobility time was significantly shortened in the microcephalic group. The results suggest that the swimming immobility time is an indicator of adaptability to novel situation rather than an expression of helplessness, lowered mood or depressed state as originally proposed by Porsolt et al. (author)

  19. Effects of Laminaria japonica polysaccharides on exercise endurance and oxidative stress in forced swimming mouse model.

    Science.gov (United States)

    Yan, Feiwei; Hao, Haitao

    2016-12-01

    Polysaccharides are the major active ingredients responsible for the bioactivities of Laminaria japonica. However, the effects of L. japonica polysaccharides (LJP) on exercise endurance and oxidative stress have never been investigated. Therefore, this study was conducted to investigate the effects of LJP on exercise endurance and oxidative stress in a forced swimming mouse model. The animals were divided into four groups, namely the control (C), LJP-75, LJP-150, and LJP-300 groups, which received physiological saline and 75, 150, and 300 mg kg(-1) LJP, respectively, by gavage once a day for 28 days. This was followed by a forced swimming test and measurements of various biochemical parameters. LJP increased swimming time to exhaustion, the liver and muscle glycogen content, and levels of superoxide dismutase, glutathione peroxidase, and catalase in the serum, liver, and muscle, which were accompanied by corresponding decreases in the malondialdehyde (MDA) content of the same tissues. Furthermore, decreases in blood lactic acid and serum myeloperoxidase (MPO) levels were observed. LJP enhanced exercise endurance and protected mice against exhaustive exercise-induced oxidative stress.

  20. Effects of swim stress and fluoxetine on 5-HT1A receptor gene expression and monoamine metabolism in the rat brain regions.

    Science.gov (United States)

    Shishkina, G T; Kalinina, T S; Dygalo, N N

    2012-07-01

    Changes in gene expression of the brain serotonin (5-HT) 1A receptors may be important for the development and ameliorating depression, however identification of specific stimuli that activate or reduce the receptor transcriptional activity is far from complete. In the present study, the forced swim test (FST) exposure, the first stress session of which is already sufficient to induce behavioral despair in rats, significantly increased 5-HT1A receptor mRNA levels in the brainstem, frontal cortex, and hippocampus at 24 h. In the brainstem and frontal cortex, the elevation in the receptor gene expression after the second forced swim session was not affected following chronic administration of fluoxetine, while in the cortex, both control and FST values were significantly reduced in fluoxetine-treated rats. In contrast to untreated rats, no increase in hippocampal 5-HT1A receptor mRNA was observed in response to FST in rats chronically treated with fluoxetine. Metabolism of 5-HT (5-HIAA/5-HT) in the brainstem was significantly decreased by fluoxetine and further reduced by swim stress, showing a certain degree of independence of these changes on 5-HT1A receptor gene expression that was increased in this brain region only after the FST, but not after fluoxetine. FST exposure also decreased the brainstem dopamine metabolism, which was unexpectedly positively correlated with 5-HT1A receptor mRNA levels in the frontal cortex. Together, these data suggest that the effects of the forced swim stress as well as fluoxetine involve brain region-dependent alterations in 5-HT1A receptor gene transcription, some of which may be interrelated with concomitant changes in catecholamine metabolism.

  1. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi

    Directory of Open Access Journals (Sweden)

    Arjan P. Palstra

    2015-01-01

    Full Text Available Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (Uopt in m s-1 or body lengths s-1, BL s-1 were assessed and then applied to determine the effects of long-term forced and sustained swimming at Uopt on growth performance of juvenile yellowtail kingfish. Uopt was quantified in Blazka-type swim-tunnels for 145 mm, 206 mm and 311 mm juveniles resulting in values of: 1 0.70 m s-1 or 4.83 BL s-1, 2 0.82 m s-1 or 3.25 BL s-1 and 3 0.85 m s-1 or 2.73 BL s-1. Combined with literature data from larger fish, a relation of Uopt (BL s-1 = 234.07(BL-0.779 (R2= 0.9909 was established for this species. Yellowtail kingfish, either forced to perform sustained swimming exercise at an optimal speed of 2.46 BL s-1 (‘swimmers’ or allowed to perform spontaneous activity at low water flow (‘resters’ in a newly designed 3,600 L oval flume (with flow created by an impeller driven by an electric motor, were then compared. At the start of the experiment, ten fish were sampled representing the initial condition. After 18 days, swimmers (n= 23 showed a 92% greater increase in BL and 46% greater increase in BW as compared to resters (n= 23. As both groups were fed equal rations, feed conversion ratio (FCR for swimmers was 1.21 vs. 1.74 for resters. Doppler ultrasound imaging showed a statistically significant higher blood flow (31% in the ventral aorta of swimmers vs. resters (44 ± 3 mL min-1 vs. 34 ± 3 mL min-1, respectively, under anesthesia. Thus growth performance can be rapidly improved by optimal swimming, without larger feed investments.

  2. Effects of high-intensity swimming training on the bones of ovariectomized rats.

    Science.gov (United States)

    Oh, Taewoong; Tanaka, Sakura; Naka, Tatsuki; Igawa, Shoji

    2016-09-01

    This study was performed to assess the effects of high-intensity intermittent swimming training(HIT) on bone in ovariectomized rats. Six-week-old female Sprague-Dawley rats were randomly assigned to either sham operation or bilateral ovariectomy. After surgery, they were divided into the following four groups: 1) sham-operated sedentary (S), 2) sham-operated exercise training (SE), 3) OVX sedentary (O), 4) OVX exercise training (OE) 5) OVX given 17β-estradiol (OE2) and 6) OVX exercise training and given 17β-estradiol (OEE). SE, OE and OEE rats were used extremely high-intensity swim exercise. The rats repeated fourteen 20-s swimming bouts with a weight equivalent to 14, 15, and 16% of body weight for the first 5, the next 9, and the last 5 days, respectively. Between exercise bouts, a 10-s pause was allowed. HIT was originally designed as an exercise method; a method that very quickly induces an increase in the maximum oxygen intake (Tabata I et al., 1996). OEE and OE2 rats were subcutaneously injected ethanol with 25μg/kg body weight 17β-estradiol 3 times per week. Bone strength, bone mineral density and trabecular bone parameters were measured after a 8-weeks experimental period. Bone strength was significantly higher in the SE, OE, OE2 and OEE group compared with the O group. BV/TV was significant increase in the SE, OE groups compared with the O group. BMD showed no difference in the OE group compared with the O group. This study demonstrate some beneficial effects of postmenopausal osteoporosis of high-intensity intermittent swimming training on bone structure and strength.

  3. Individual differences in the forced swimming test and the effect of environmental enrichment: searching for an interaction.

    Science.gov (United States)

    Sequeira-Cordero, A; Mora-Gallegos, A; Cuenca-Berger, P; Fornaguera-Trías, J

    2014-04-18

    Animals with low and high immobility in the forced swimming test (FST) differ in a number of neurobehavioral factors. A growing body of evidence suggests that the exposure to enriched environments mediates a number of changes in the brain. Therefore, we studied if animals' individuality can somehow modulate the response to environmental stimuli. Male rats were classified according to their immobility time scores in the FST test session as animals with low, medium or high immobility. Then, rats from groups with low and high immobility were randomly distributed in two groups to be reared in different housing conditions (i.e., enriched and standard conditions) during 8weeks. Animals were subjected to the open field test (OFT) before and 6weeks after the start of housing protocol. Rats with high immobility in the FST also showed high ambulation and high rearing time in the first OFT. Such findings were not observed in the second OFT. Conversely, an effect of environmental enrichment was found in the second OFT where enriched animals showed lower ambulation and higher grooming time than the standard control group. Rats were sacrificed after the housing protocol and neurochemical content and/or gene expression were studied in three different brain regions: the prefrontal cortex, the hippocampus and the nucleus accumbens. Rats with low immobility showed significantly higher accumbal 5-HT levels than animals with high immobility, whereas no neurochemical differences were observed between enriched and standard animals. Regarding expression data, however, an effect of enrichment on accumbal corticotropin-releasing factor (CRF) and its receptor 1 (CRFR1) levels was observed, and such effect depended on immobility levels. Thus, our results not only allowed us to identify a number of differences between animals with low and high immobility or animals housed in standard and enriched conditions, but also suggested that animals' individuality modulated in some way the response to

  4. Paroxetine blunts the corticosterone response to swim-induced stress and increases depressive-like behavior in a rat model of postpartum depression

    DEFF Research Database (Denmark)

    Overgaard, Agnete; Lieblich, Stephanie E; Richardson, Robin

    2018-01-01

    Perinatal depression (PND) affects 15% of women. During the perinatal period both stress- and gonadal hormones fluctuate widely. Putatively, these fluctuations are involved in PND disease mechanisms. The serotonin system is sensitive to such hormone fluctuations, and serotonin reuptake inhibitors...... depression. In the rat model corticosterone (CORT; 40mg/kgs.c.) was administered in Sprague Dawley rats across postpartum day (PD)2 to PD14. Stress response was measured during the first exposure to the forced swim test (FST1), and depressive-like behavior was measured in both FST1 and FST2. We found...... that paroxetine completely blunted the swim stress-induced CORT response and increased depressive-like behavior in both FST1 and FST2. Our findings suggest that in the postpartum context, SSRIs compromise stress axis dynamics, which are needed for a healthy stress response. This is likely unfavorable...

  5. Environmental constraints on motor abilities used in grooming, swimming, and eating by decorticate rats.

    Science.gov (United States)

    Whishaw, I Q; Nonneman, A J; Kolb, B

    1981-10-01

    In a number of successive tests, grooming, swimming, and eating behaviors of decorticate rats were reexamined by evoking the behaviors in various circumstances (stimulus conditions). The rats showed normal-length grooming sequences during spontaneous home cage grooming; when grooming was elicited by removing the rats from their home cage and soaking their fur by a brief swim, grooming-sequence length was abbreviated. In cold (18 degrees C) water, they swam well and with exaggerated vigor and frequently inhibited forelimb movements; in warm (37 degrees C) water, they swam poorly and paddled with all four limbs. To eat small pieces of food, they sat up and used their forepaws as do normal rats, but they frequently dropped the food; they did not use their forepaws to eat large pieces of food. When given powdered food, they first tried to grasp it in their mouth while they scratched at the floor surface with their front limbs; thereafter, they became increasingly proficient in licking it up. Thus, in a narrow range of stimulus conditions, decorticate rats can make movements resembling those of normal rats. They also improve with practice in some (eating powdered food) but not other (forepaw immobility, eating large food pellets) tasks. The study shows that in order to elucidate the role of the cortex in control of motor behavior, it is necessary to obtain "behavior profiles" of each behavior by testing the animals repeatedly and under widely varying test conditions.

  6. The antidepressant-like effect of ethynyl estradiol is mediated by both serotonergic and noradrenergic systems in the forced swimming test.

    Science.gov (United States)

    Vega-Rivera, N M; López-Rubalcava, C; Estrada-Camarena, E

    2013-10-10

    17α-Ethynyl-estradiol (EE2, a synthetic steroidal estrogen) induces antidepressant-like effects in the forced swimming test (FST) similar to those induced by 5-HT and noradrenaline reuptake inhibitors (dual antidepressants). However, the precise mechanism of action of EE2 has not been studied. In the present study, the participation of estrogen receptors (ERs) and the serotonergic and the noradrenergic presynaptic sites in the antidepressant-like action of EE2 was evaluated in the FST. The effects of the ER antagonist ICI 182,780 (10 μg/rat; i.c.v.), the serotonergic and noradrenergic terminal destruction with 5,7-dihydroxytryptamine (5,7-DHT; 200 μg/rat, i.c.v.), and N-(2-chloro-ethyl)-N-ethyl-2-bromobenzylamine (DSP4; 10mg/kg, i.p.) were studied in ovariectomized rats treated with EE2 and subjected to the FST. In addition, the participation of α2-adrenergic receptors in the antidepressant-like action of EE2 was explored using the selective α2-receptor antagonist idazoxan (0.25, 0.5 and 1.0mg/kg, i.p.). EE2 induced an antidepressant-like action characterized by a decrease in immobility behavior with a concomitant increase in swimming and climbing behaviors. The ER antagonist, 5,7-DHT, DSP4, and idazoxan blocked the effects of EE2 on the immobility behavior, whereas ICI 182,780 and 5,7-DHT affected swimming behavior. The noradrenergic compound DSP4 altered climbing behavior, while Idazoxan inhibited the increase of swimming and climbing behaviors induced by EE2. Our results suggest that the antidepressant-like action of EE2 implies a complex mechanism of action on monoaminergic systems and estrogen receptors. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Papaver Rhoeas L. Hydroalcoholic Extract Exacerbates Forced Swimming Test-Induced Depression in Mice

    OpenAIRE

    Naser Osanloo; Akram Najafi-Abedi; Fatemeh Jafari; Farshid Javid; Mohsen Pirpiran; Mohammad-Reza Memar-Jafari; Seyed Ali Mousavi-Khosravi; Mohammad Rahimzadeh-Behzadi; Mina Ranjbaran; Hedayat Sahraei

    2016-01-01

    Introduction: Depression is one of the most frequent psychiatric disorders in the world with occurs with higher incidence in women. In the present study, the effect of water-alcoholic extract of Papaver rhoeas L. on forced swimming test (FST) in Swiss-Webster mice were examined. Methods: We used Swiss-Webster mice (20-25 g) to execute FST on them. The plant extract (1, 10, 30, and 100 mg/kg) was injected to the animals 30 minutes before each session. Fluoxetine (20 mg/k...

  8. Methods for measurement of energy expenditure and substrate concentrations in swimming rats.

    Science.gov (United States)

    Benthem, L; Bolhuis, J W; van der Leest, J; Steffens, A B; Zock, J P; Zijlstra, W G

    1994-07-01

    A measuring system is described for the determination of oxygen consumption (Vo2) and carbon dioxide production (Vco2) in swimming rats. Vo2 and Vco2 were measured by means of an O2-analyzer (Ametek S3A) and a mass spectrometer (Balzers QMG 511), respectively, combined with a gas flow meter. The measurements were made in a 5-1 metabolic chamber on top of a swimming pool in which a water flow of 0.22 m/s was maintained. The rats were fitted with an indwelling catheter with its tip at the entrance of the right atrium for the repeated determination of energy substrate and hormone concentrations, before, during, and after swimming. The inaccuracy of the Vo2 and Vco2 measurements was 0.18% and 0.31% of the reading, respectively; the imprecision was 2.15% and 2.59%. This high accuracy and precision of the system was attained by measuring room air for 20 s after each 100 s of measuring air from the metabolic chamber, and by using demineralized water in the swimming pool. Vo2 during steady-state swimming was 1.89 +/- 0.06 mmol/kg.min (ca. 60% Vo2max), indicating moderate exercise. Respiratory quotient (RQ), during steady-state exercise, was 0.80 +/- 0.01. Vo2 and RQ resulted in rates for carbohydrate and fat utilization of 15.6 +/- 0.8 and 15.1 +/- 0.7 mg/kg.min, respectively.

  9. Effects of high-intensity swimming training on the bones of ovariectomized rats

    OpenAIRE

    Oh, Taewoong; Tanaka, Sakura; Naka, Tatsuki; Igawa, Shoji

    2016-01-01

    [Purpose] This study was performed to assess the effects of high-intensity intermittent swimming training(HIT) on bone in ovariectomized rats. [Methods] Six-week-old female Sprague-Dawley rats were randomly assigned to either sham operation or bilateral ovariectomy. After surgery, they were divided into the following four groups: 1) sham-operated sedentary (S), 2) sham-operated exercise training (SE), 3) OVX sedentary (O), 4) OVX exercise training (OE) 5) OVX given 17?-estradiol (OE2) and 6) ...

  10. Assessment of the effect of prolonged forced swimming on CD-1 mice sperm morphology with and without antioxidant supplementation.

    Science.gov (United States)

    Rodriguez, I; Diaz, A; Vaamonde, D

    2016-04-01

    As physical exercise has been shown to negatively affect sperm morphology, this study was undertaken to assess the effect of a 3-min forced swimming protocol during 50 days, with and without administration of antioxidants [N-acetylcysteine (NAC) and trans-resveratrol], on sperm morphology in CD-1 mice. Forty-four 13-week-old CD-1 mice were randomly allocated to four different groups: mice not submitted to exercise, control group (CG), mice submitted to swimming without administration of antioxidants (EX), mice submitted to swimming that received trans-resveratrol supplementation [exercise group (EX)+Resv] and mice submitted to swimming exercise that received NAC supplementation (EX+NAC). The EX showed 30.5% of spermatozoa with normal morphology, showing significant differences with regard to the CG, which showed 58.5%. The groups receiving antioxidant supplements showed significantly higher percentages of spermatozoa with normal morphology in comparison with the EX group (EX+Resv: 64.1%, EX+NAC: 48.2%). The imposed model of forced swimming caused alterations in sperm morphology. The antioxidants employed seem to be suitable antioxidants for avoiding exercise-associated sperm morphology anomalies in prolonged forced swimming exercise. Trans-resveratrol has proven to be more efficient for this purpose. © 2015 Blackwell Verlag GmbH.

  11. Effects of swimming training and free mobilization on bone mineral densities of rats with the immobilization-induced osteopenia

    International Nuclear Information System (INIS)

    Karatosun, H.; Erdogan, A.; Akgun, C.; Cetin, C.; Yeldiz, M.

    2006-01-01

    To investigate the possible effects of regular swimming exercise on bone mineral density (BMD) compared with free activity after cast immobilization of rats. We carried out the study from April 2005 to June 2005 at the Department of Sports Medicine, Medical School of Suleyman Demirel University, Isparta, Turkey. The study included a total of 24 female Wistar rats. The rats were randomized to control (n = 6), swimming training (ST) n = 9, and free mobilization (FM) n = 9 groups. We measured Bone mineral densities of femur and vertebra of all rats with a total body scanner using software specifically designed for small animals, before study started and at weeks 3 and 7. Timepoints corresponded to basal, after cast removal (ACIM), and after 3 weeks of free mobilization (AFM) or swimming training (AST). We immobilized the right hindlimb of each ST and FM animal with a cast while the left hindlimbs were kept free. After 3 weeks, the casts were removed. Then we allowed the rats to move freely in their cage for one week, after which the animals in ST group started to swim for 5 days a week for 3 weeks for 30 minutes per day. The group FM rats moved freely in the cage. Bone mineral density of the femur and vertebra after cast immobilization was significantly decreased compared with both their basal and age-matched control group. After mobilization, significant increases occurred in both groups according to ACIM. Similar but milder changes were observed in free limbs femur BMD of rats. Interestingly, vertebra BMD of swimming group was also higher than its age-matched control group (p<0.05). Our study showed that swimming exercise had a significant rehabilitative effect on BMD loss associated with immobilization. Further studies are needed to investigate the effects of swimming on other bone properties. (author)

  12. Biomechanical and structural parameters of tendons in rats subjected to swimming exercise.

    Science.gov (United States)

    Bezerra, M A; Santos de Lira, K D; Coutinho, M P G; de Mesquita, G N; Novaes, K A; da Silva, R T B; de Brito Nascimento, A K; Inácio Teixeira, M F H B; Moraes, S R A

    2013-12-01

    The aim of this study was to evaluate the effect of swimming exercise, without overloading, on the biomechanical parameters of the calcaneal tendon of rats. 27 male Wistar rats (70 days) were distributed randomly into 2 groups, Control Group (CG; n=15) with restricted movements inside the cage and Swimming Group (SG; n=12), subjected to exercise training in a tank with a water temperature of 30±1°C, for 1 h/day, 5 days/week for 8 weeks. All animals were kept in a reversed light/dark cycle of 12 h with access to food and water ad libitum. After that, they were anesthetized and had their calcaneus tendons collected from their left rear paws. The tendon was submitted to a mechanical test on a conventional test machine. From the stress vs. strain curve, the biomechanical data were analyzed. For the statistical analysis, the Student-T test was used (penergy of deformation/tendon cross sectional area (p=0.017) and elastic modulus of the tendon (p=0.013) showed positive outcomes in SG. There was no difference in the other parameters. The results indicate that the swimming exercise training, without overloading, was an important stimulus for improving the biomechanical parameters and structural properties of the calcaneal tendon. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Impact of metformin treatment and swimming exercise on visfatin levels in high-fat-induced obesity rats.

    Science.gov (United States)

    Gao, Ya; Wang, Changjiang; Pan, Tianrong; Luo, Li

    2014-02-01

    Visfatin is a recently discovered adipocytokine that contributes to glucose and obesity-related conditions. Until now, its responses to the insulin-sensitizing agent metformin and to exercise are largely unknown. We aim to investigate the impact of metformin treatment and/or swimming exercise on serum visfatin and visfatin levels in subcutaneous adipose tissue (SAT), peri-renal adipose tissue (PAT) and skeletal muscle (SM) of high-fat-induced obesity rats. Sprague-Dawley rats were fed a normal diet or a high-fat diet for 16 weeks to develop obesity model. The high-fat-induced obesity model rats were then randomized to metformin (MET), swimming exercise (SWI), or adjunctive therapy of metformin and swimming exercise (MAS), besides high-fat obesity control group and a normal control group, all with 10 rats per group. Zoometric and glycemic parameters, lipid profile, and serum visfatin levels were assessed at baseline and after 6 weeks of therapy. Visfatin levels in SAT, PAT and SM were determined by Western Blot. Metformin and swimming exercise improved lipid profile, and increased insulin sensitivity and body weight reduction were observed. Both metformin and swimming exercise down-regulated visfatin levels in SAT and PAT, while the adjunctive therapy conferred greater benefits, but no changes of visfatin levels were observed in SM. Our results indicate that visfatin down-regulation in SAT and PAT may be one of the mechanisms by which metformin and swimming exercise inhibit obesity.

  14. Antidepressant-Like Effect of 1α-Hydroxyvitamin D3 on Mice in the Forced Swimming Test.

    Science.gov (United States)

    Kawaura, Akihiko; Kitamura, Yoshihisa; Tanida, Noritoshi; Akiyama, Junichi; Mizutani, Masatoshi; Harada, Kazuhiro; Morishita, Motoyoshi; Inoue, Shigeki; Kano, Yoshio; Okano, Toshio; Takeda, Eiji

    2017-01-01

    We examined the effect of 1α-hydroxyvitamin D 3 [1α(OH)D 3 ] on mice in the forced swimming test. Intragastric administration of 1.0 μg/kg of 1α(OH)D 3 reduced immobility time in the forced swimming test. At all concentrations tested (0.5, 1.0, 2.0 μg/kg), 1α(OH)D 3 had no effect on locomotor activity, compared with controls. These results suggest that 1α(OH)D 3 may have antidepressant-like activity.

  15. Development of Swimming Human Simulation Model Considering Rigid Body Dynamics and Unsteady Fluid Force for Whole Body

    Science.gov (United States)

    Nakashima, Motomu; Satou, Ken; Miura, Yasufumi

    The purpose of this study is to develop a swimming human simulation model considering rigid body dynamics and unsteady fluid force for the whole body, which will be utilized to analyze various dynamical problems in human swimming. First, the modeling methods and their formulations for the human body and the fluid force are respectively described. Second, experiments to identify the coefficients of the normal drag and the added mass are conducted by use of an experimental setup, in which a limb model rotates in the water, and its rotating angle and the bending moment at the root are measured. As the result of the identification, the present model for the fluid force was found to have satisfactory performance in order to represent the unsteady fluctuations of the experimental data, although it has 10% error. Third, a simulation for the gliding position is conducted in order to identify the tangential drag coefficient. Finally, a simulation example of standard six beat front crawl swimming is shown. The swimming speed of the simulation became a reasonable value, indicating the validity of the present simulation model, although it is 7.5% lower than the actual swimming.

  16. Antidepressant-like responses in the forced swimming test elicited by glutathione and redox modulation.

    Science.gov (United States)

    Rosa, Juliana M; Dafre, Alcir Luiz; Rodrigues, Ana Lúcia S

    2013-09-15

    Glutathione (GSH) displays a broad range of functions, among them a role as a neuromodulator with some neuroprotective properties. Taking into account that oxidative stress has been associated with depressive disorders, this study investigated the possibility that GSH, a major cell antioxidant, elicits an antidepressant-like effect in mice. Thus, GSH was administered by i.c.v. route to mice that were tested in the forced swimming test and in the tail suspension test, two predictive tests for antidepressant drug activity. In addition, GSH metabolism and the redox environment were modulated in order to study the possible mechanisms underlying the effects of GSH in the forced swimming test. The administration of GSH decreased the immobility time in the forced swimming test (300-3000nmol/site) and tail suspension test (100-1000nmol/site), consistent with an antidepressant-like effect. GSH depletion elicited by l-buthionine sulfoximine (3.2μmol/site, i.c.v.) did not alter the antidepressant-like effect of GSH, whereas the inhibition of extracellular GSH catabolism by acivicin (100nmol/site, i.c.v.) prevented the antidepressant-like effect of GSH. Moreover, a sub-effective dose (0.01nmol/site, i.c.v.) of the oxidizing agent DTNB (5,5'-dithiobis(2-nitrobenzoic acid)) potentiated the effect of GSH (100nmol/site, i.c.v.), while the pretreatment (25-100mg/kg, i.p.) with the reducing agent DTT (dl-dithiothreitol) prevented the antidepressant-like effect of GSH (300nmol/site, i.c.v.). DTNB (0.1nmol/site, i.c.v.), produced an antidepressant-like effect, per se, which was abolished by DTT (25mg/kg, i.p.). The results show, for the first time, that centrally administered GSH produces an antidepressant-like effect in mice, which can be modulated by the GSH metabolism and the thiol/disulfide reagents. The redox environment may constitute a new venue for future antidepressant-drug development. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Swimming training alleviated insulin resistance through Wnt3a/β-catenin signaling in type 2 diabetic rats

    Directory of Open Access Journals (Sweden)

    Qiang Yang

    2017-11-01

    Full Text Available Objective(s: Increasing evidence suggests that regular physical exercise improves type 2 diabetes mellitus (T2DM. However, the potential beneficial effects of swimming on insulin resistance and lipid disorder in T2DM, and its underlying mechanisms remain unclear. Materials and Methods: Rats were fed with high fat diet and given a low dosage of Streptozotocin (STZ to induce T2DM model, and subsequently treated with or without swimming exercise. An 8-week swimming program (30, 60 or 120 min per day, 5 days per week decreased body weight, fasting blood glucose and fasting insulin. Results: Swimming ameliorated lipid disorder, improved muscular atrophy and revealed a reduced glycogen deposit in skeletal muscles of diabetic rats. Furthermore, swimming also inhibited the activation of Wnt3a/β-catenin signaling pathway, decreased Wnt3a mRNA and protein level, upregulated GSK3β phosphorylation activity and reduced the expression of β-catenin phosphorylation in diabetic rats. Conclusion: The trend of the result suggests that swimming exercise proved to be a potent ameliorator of insulin resistancein T2DM through the modulation of Wnt3a/β-catenin pathway and therefore, could present a promising therapeutic measure towards the treatment of diabetes and its relatives.

  18. Swimming reduces the severity of physical and psychological dependence and voluntary morphine consumption in morphine dependent rats.

    Science.gov (United States)

    Fadaei, Atefeh; Gorji, Hossein Miladi; Hosseini, Shahrokh Makvand

    2015-01-15

    Previous studies have indicated that voluntary exercise decreases the severity of the anxiogenic-like behaviors in both morphine-dependent and withdrawn rats. This study examined the effects of regular swimming exercise during the development of dependency and spontaneous morphine withdrawal on the anxiety-depression profile and voluntary morphine consumption in morphine dependent rats. The rats were chronically treated with bi-daily doses (10 mg/kg, at 12h intervals) of morphine over a period of 14 days. The exercising rats were allowed to swim (45 min/d, five days per a week, for 14 or 21 days) during the development of morphine dependence and withdrawal. Then, rats were tested for the severity of morphine dependence, the elevated plus-maze (EPM), sucrose preference test (SPT) and voluntary morphine consumption using a two-bottle choice paradigm in animal models of craving. The results showed that withdrawal signs were decreased in swimmer morphine dependent rats than sedentary rats (Pmorphine-dependent and withdrawn rats exhibited an increase in EPM open arm time and entries (Pmorphine was less in the swimmer morphine-withdrawn rats than the sedentary groups during four periods of the intake of drug (Pmorphine dependence and voluntary morphine consumption with reducing anxiety and depression in morphine-dependent and withdrawn rats. Thus, swimming exercise may be a potential method to ameliorate some of the deleterious behavioral consequences of morphine dependence. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Performance during a strenuous swimming session is associated with high blood lactate: pyruvate ratio and hypoglycemia in fasted rats.

    Science.gov (United States)

    Travassos, P B; Godoy, G; De Souza, H M; Curi, R; Bazotte, R B

    2018-03-26

    The aim of this study was to investigate the effect of lactatemia elevation and glycemia reduction on strenuous swimming performance in fasted rats. Three rats were placed in a swimming tank at the same time. The first rat was removed immediately (control group) and the remaining ones were submitted to a strenuous swimming session. After the second rat was exhausted (Exh group), the third one was immediately removed from the water (Exe group). According to the period of time required for exhaustion, the rats were divided into four groups: low performance (3-7 min), low-intermediary performance (8-12 min), high-intermediary performance (13-17 min), and high performance (18-22 min). All rats were removed from the swimming tanks and immediately killed by decapitation for blood collection or anesthetized for liver perfusion experiments. Blood glucose, lactate, and pyruvate concentrations, blood lactate/pyruvate ratio, and liver lactate uptake and its conversion to glucose were evaluated. Exhaustion in low and low-intermediary performance were better associated with higher lactate/pyruvate ratio. On the other hand, exhaustion in high-intermediary and high performance was better associated with hypoglycemia. Lactate uptake and glucose production from lactate in livers from the Exe and Exh groups were maintained. We concluded that there is a time sequence in the participation of lactate/pyruvate ratio and hypoglycemia in performance during an acute strenuous swimming section in fasted rats. The liver had an important participation in preventing hyperlactatemia and hypoglycemia during swimming through lactate uptake and its conversion to glucose.

  20. Level of Interleukins IL-6 and IL-15 in Blood Plasma of Mice after Forced Swimming Test.

    Science.gov (United States)

    Kapilevich, L V; Kironenko, T A; Zakharova, A N; Kabachkova, A V; Orlov, S N

    2017-05-01

    We measured the concentrations of IL-6 and IL-15 in blood plasma of mice at different terms after forced swimming, taking into account exercise intensity and preliminary training. It was shown that training was an important factor affecting blood plasma level of IL both at rest and after single forced swimming: in trained animals, the concentration of both myokines increased immediately after swimming, while in untrained animals, this increase was observed only after 5 h. Changes in cytokine production against the background of training can be associated with various factors, including neuroendocrine mechanisms, stress, modification of intracellular signaling, as well as reorganization of transcriptional mechanisms in muscle fibers. The most important factor is shift in the ratio of monovalent cations (sodium and potassium) in the cytoplasm.

  1. Swimming training prevents coronary endothelial dysfunction in ovariectomized spontaneously hypertensive rats

    Directory of Open Access Journals (Sweden)

    E.R.G. Claudio

    Full Text Available Estrogen deficiency and hypertension are considered major risk factors for the development of coronary heart disease. On the other hand, exercise training is considered an effective form to prevent and treat cardiovascular diseases. However, the effects of swimming training (SW on coronary vascular reactivity in female ovariectomized hypertensive rats are not known. We aimed to evaluate the effects of SW on endothelium-dependent coronary vasodilation in ovariectomized hypertensive rats. Three-month old spontaneously hypertensive rats (SHR, n=50 were divided into four groups: sham (SH, sham plus swimming training (SSW, ovariectomized (OVX, and ovariectomized plus swimming training (OSW. The SW protocol (5 times/week, 60 min/day was conducted for 8 weeks. The vasodilatory response was measured in isolated hearts in the absence and presence of a nitric oxide synthase inhibitor (L-NAME, 100 µM. Cardiac oxidative stress was evaluated in situ by dihydroethidium fluorescence, while the expression of antioxidant enzymes (SOD-2 and catalase and their activities were assessed by western blotting and spectrophotometry, respectively. Vasodilation in SHR was significantly reduced by OVX, even in the presence of L-NAME, in conjunction with an increased oxidative stress. These effects were prevented by SW, and were associated with a decrease in oxidative stress. Superoxide dismutase 2 (SOD-2 and catalase expression increased only in the OSW group. However, no significant difference was found in the activity of these enzymes. In conclusion, SW prevented the endothelial dysfunction in the coronary bed of ovariectomized SHR associated with an increase in the expression of antioxidant enzymes, and therefore may prevent coronary heart disease in hypertensive postmenopausal women.

  2. Antidepressant-like effects of young green barley leaf (Hordeum vulgare L.) in the mouse forced swimming test.

    Science.gov (United States)

    Yamaura, Katsunori; Nakayama, Noriyuki; Shimada, Maki; Bi, Yuanyuan; Fukata, Hideki; Ueno, Koichi

    2012-01-01

    Young green barley leaf is one of the richest sources of antioxidants and has been widely consumed for health management in Japan. In this study, we examined whether oral administration of young green barley leaf has an antidepressant effect on the forced swimming test in mice. Mice were individually forced to swim in an open cylindrical container, one hour after oral administration of young green barley leaf (400 or 1000 mg / kg) or imipramine (100 mg / kg). Expression of mRNA for nerve growth factor (NGF), brain-derived neurotrophic factor, and glucocorticoid receptor in the brain was analyzed using real-time quantitative polymerase chain reaction (PCR). There was a significant antidepressant-like effect in the forced swimming test; both 400 and 1000 mg / kg young green barley leaves, as well as the positive control imipramine (100 mg / kg), reduced the immobility duration compared to the vehicle group. The expression of mRNA for NGF detected in the hippocampus immediately after the last swimming test was higher than that in the non-swimming group (Nil). Oral administration of imipramine suppressed this increase to the level of the Nil group. Young green barley leaf (400 and 1000 mg / kg) also showed a moderate decrease in the expression of mRNA for NGF, in a dose-dependent manner. Oral administration of young green barley leaf is able to produce an antidepressant-like effect in the forced swimming test. Consequently it is possible that the antidepressant-like effects of the young green barley leaf are, at least in part, mediated by an inhibition of the increase in the hippocampus levels of NGF.

  3. The cardiovascular and endocrine responses to voluntary and forced diving in trained and untrained rats

    Science.gov (United States)

    DiNovo, Karyn. M.; Connolly, Tiffanny M.

    2010-01-01

    The mammalian diving response, consisting of apnea, bradycardia, and increased total peripheral resistance, can be modified by conscious awareness, fear, and anticipation. We wondered whether swim and dive training in rats would 1) affect the magnitude of the cardiovascular responses during voluntary and forced diving, and 2) whether this training would reduce or eliminate any stress due to diving. Results indicate Sprague-Dawley rats have a substantial diving response. Immediately upon submersion, heart rate (HR) decreased by 78%, from 453 ± 12 to 101 ± 8 beats per minute (bpm), and mean arterial pressure (MAP) decreased 25%, from 143 ± 1 to 107 ± 5 mmHg. Approximately 4.5 s after submergence, MAP had increased to a maximum 174 ± 3 mmHg. Blood corticosterone levels indicate trained rats find diving no more stressful than being held by a human, while untrained rats find swimming and diving very stressful. Forced diving is stressful to both trained and untrained rats. The magnitude of bradycardia was similar during both voluntary and forced diving, while the increase in MAP was greater during forced diving. The diving response of laboratory rats, therefore, appears to be dissimilar from that of other animals, as most birds and mammals show intensification of diving bradycardia during forced diving compared with voluntary diving. Rats may exhibit an accentuated antagonism between the parasympathetic and sympathetic branches of the autonomic nervous system, such that in the autonomic control of HR, parasympathetic activity overpowers sympathetic activity. Additionally, laboratory rats may lack the ability to modify the degree of parasympathetic outflow to the heart during an intense cardiorespiratory response (i.e., the diving response). PMID:19923359

  4. Inhibition of progesterone metabolism mimics the effect of progesterone withdrawal on forced swim test immobility.

    Science.gov (United States)

    Beckley, Ethan H; Finn, Deborah A

    2007-10-01

    Withdrawal from high levels of progesterone in rodents has been proposed as a model for premenstrual syndrome or postpartum depression. Forced swim test (FST) immobility, used to model depression, was assessed in intact female DBA/2J mice following progesterone withdrawal (PWD) or treatment with the 5alpha-reductase inhibitor finasteride. Following 5 daily progesterone injections (5 mg/kg IP) FST immobility increased only in mice withdrawn for 3 days (pimmobility. PWD and finasteride treatment, both of which reduce allopregnanolone levels, were associated with increased FST immobility in female DBA/2J mice. These findings suggest that decreased levels of the GABAergic neurosteroid allopregnanolone contribute to symptoms of PWD. Future studies of PWD may provide information about human conditions that are associated with hormone changes such as premenstrual syndrome or postpartum depression.

  5. Conditioned taste avoidance induced by forced and voluntary wheel running in rats.

    Science.gov (United States)

    Forristall, J R; Hookey, B L; Grant, V L

    2007-03-01

    Voluntary exercise by rats running in a freely rotating wheel (free wheel) produces conditioned taste avoidance (CTA) of a flavored solution consumed before running [e.g., Lett, B.T., Grant, V.L., 1996. Wheel running induces conditioned taste aversion in rats trained while hungry and thirsty. Physiol. Behav. 59, 699-702]. Forced exercise, swimming or running, also produces CTA in rats [e.g., Masaki, T., Nakajima, S., 2006. Taste aversion induced by forced swimming, voluntary running, forced running, and lithium chloride injection treatments. Physiol. Behav. 88, 411-416]. Energy expenditure may be the critical factor in producing such CTA. If so, forced running in a motorized running wheel should produce CTA equivalent to that produced by a similar amount of voluntary running. In two experiments, we compared forced running in a motorized wheel with voluntary running in a free wheel. Mean distance run over 30 min was equated as closely as possible in the two apparatuses. Both types of exercise produced CTA relative to sedentary, locked-wheel controls. However, voluntary running produced greater CTA than forced running. We consider differences between running in the free and motorized wheels that may account for the differences in strength of CTA.

  6. Enhancement of the anti-immobility action of antidepressants by risperidone in the forced swimming test in mice.

    Science.gov (United States)

    Rogóż, Zofia; Kabziński, Marcin

    2011-01-01

    The aim of the present study was to examine the effect of antidepressants (ADs) belonging to different pharmacological groups and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. The antidepressants: citalopram, fluvoxamine, sertraline, reboxetine, milnacipran (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Co-treatment with reboxetine or milnacipran (10 mg/kg) and risperidone in a lower dose of 0.05 mg/kg or with sertraline, reboxetine (5 and 10 mg/kg), citalopram, fluvoxamine, milnacipran (10 mg/kg) and risperidone in a higher dose of 0.1 mg/kg produced antidepressant-like effect in the forced swimming test. WAY100635 (a 5-HT(1A) receptor antagonist) inhibited the effects induced by co-administration of ADs and risperidone. Active behavior in the forced swimming test was not a consequence of an increased general activity, since the combined treatment with ADs and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that a low dose of risperidone enhances the activity of ADs in an animal model of depression, and that, among other mechanisms, 5-HT(1A) receptors may play a role in these effects.

  7. Reduction in the latency of action of antidepressants by 17 beta-estradiol in the forced swimming test.

    Science.gov (United States)

    Estrada-Camarena, E; Rivera, N M Vega; Berlanga, C; Fernández-Guasti, A

    2008-12-01

    Antidepressants (ADs) are slow to produce their therapeutic effect. This long latency promotes the development of new strategies to short their onset of action. Previous reports indicated that 17beta-estradiol (E(2)) promotes the antidepressant-like activity of fluoxetine (FLX) and desipramine (DMI) in the forced swimming test (FST). The aim of the present work was to analyze if E(2) reduces the antidepressant-like onset of action of venlafaxine (VLX), FLX, and DMI. Independent groups of ovariectomized female Wistar rats were tested in the FST and in the open field after chronic (1 to 14 days) treatment with VLX (20 mg/kg/day), FLX (1.25 mg/kg/day), or DMI (1.25 mg/kg/day) alone or in combination with a single injection of E(2) (2.5 microg/rat sc, 8 h before FST). VLX, FLX, or DMI by themselves at these doses did not induce changes in the FST at short intervals after their injection (from 1 to 7 days). The addition of E(2) promoted the antidepressant-like effect of VLX and DMI as early as day 1. Such action was also evident after 3, for FLX, and 14 days for both FLX and DMI, but not for VLX. The behavioral actions of these ADs combined with E(2) were not accompanied by increases in general activity in the open-field test. E(2) clearly reduced the latency to the onset of action for these ADs in the FST. These results represent an interesting therapeutic strategy for the treatment of depression in perimenopausal women.

  8. THE EFFECT OF INSULIN AND CARBOHYDRATE SUPPLEMENTATION ON GLYCOGEN REPLENISHMENT AMONG DIFFERENT HINDLIMB MUSCLES IN RATS FOLLOWING PROLONGED SWIMMING

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    Mei-Chich Hsu

    2012-04-01

    Full Text Available In the present study we investigated the interactive effects of insulin and carbohydrate on glycogen replenishment in different rat hindlimb muscles. Forty male Sprague Dawley rats were assigned to 5 groups, including 1 sedentary control with carbohydrate supplement (2 g glucose · kg body wt-1, 2 sedentary rats with 16 hours recovery, carbohydrate and insulin (0.5 U · kg body wt-1, 3 swimming without recovery, 4 swimming with 16 hours recovery and carbohydrate supplement, and 5 swimming with 16 hours recovery, carbohydrate and insulin. The swimming protocol consisted of two 3 h swimming sections, which were separated by a 45 min rest. The insulin and carbohydrate were administered to the rats immediately after exercise. At the end of the experiment, the soleus (S, plantaris (P, quadriceps (Q and gastrocnemius (G were surgically excised to evaluate glycogen utilization and replenishment. We observed that glycogen utilization was significantly lower in G and Q than S and P during swimming (p <0.05, and S showed the greatest capacity of glycogen resynthesis after post-exercise recovery (p <0.05. In the sedentary state, the glycogen synthesis did not differ among hindlimb muscles during insulin and carbohydrate treatments. Interestingly, with insulin and carbohydrate, the glycogen resynthesis in S and P were significantly greater than in Q and G following post-exercise recovery (p <0.05. We therefore concluded that the soleus and plantaris are the primary working muscles during swimming, and the greatest glycogen replenishment capacity of the soleus during post-exercise recovery is likely due to its highest insulin sensitivity.

  9. Brain Metabolism Alterations Induced by Pregnancy Swimming Decreases Neurological Impairments Following Neonatal Hypoxia-Ischemia in Very Immature Rats

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    Eduardo F. Sanches

    2018-06-01

    Full Text Available Introduction: Prematurity, through brain injury and altered development is a major cause of neurological impairments and can result in motor, cognitive and behavioral deficits later in life. Presently, there are no well-established effective therapies for preterm brain injury and the search for new strategies is needed. Intra-uterine environment plays a decisive role in brain maturation and interventions using the gestational window have been shown to influence long-term health in the offspring. In this study, we investigated whether pregnancy swimming can prevent the neurochemical metabolic alterations and damage that result from postnatal hypoxic-ischemic brain injury (HI in very immature rats.Methods: Female pregnant Wistar rats were divided into swimming (SW or sedentary (SE groups. Following a period of adaptation before mating, swimming was performed during the entire gestation. At postnatal day (PND3, rat pups from SW and SE dams had right common carotid artery occluded, followed by systemic hypoxia. At PND4 (24 h after HI, the early neurochemical profile was measured by 1H-magnetic resonance spectroscopy. Astrogliosis, apoptosis and neurotrophins protein expression were assessed in the cortex and hippocampus. From PND45, behavioral testing was performed. Diffusion tensor imaging and neurite orientation dispersion and density imaging were used to evaluate brain microstructure and the levels of proteins were quantified.Results: Pregnancy swimming was able to prevent early metabolic changes induced by HI preserving the energetic balance, decreasing apoptotic cell death and astrogliosis as well as maintaining the levels of neurotrophins. At adult age, swimming preserved brain microstructure and improved the performance in the behavioral tests.Conclusion: Our study points out that swimming during gestation in rats could prevent prematurity related brain damage in progeny with high translational potential and possibly interesting cost

  10. Influence of exposure of pregnant rats to tritiated water (HTO) on swimming function and brain weight of their litters

    International Nuclear Information System (INIS)

    Yang Zhiyuan; Guo Yuefeng

    1986-01-01

    In order to understand the effects of HTO exposure on the development of central nervous system in rats, the influence of exposure of pregnant rat to HTO on the swimming ability of their litters was studies. Experiment was completed in 21 rats and their 237 litters. It was found that exposure of rats to HTO at activity of 0.185 MBq/ml of body water (5 μCi/ml) or 0.740 MBq/ml (20 μCi/ml), begining on the 8th day of gestation, may retard the development of swimming ability in young litters (up to 18 day of life). These findings indicate that exposure to HTO at lower doses (0.20-1.85 Gy) may resut in a retardation of the function of the development of central nervous system in rats

  11. Kappa-opioid receptors mediate the antidepressant-like activity of hesperidin in the mouse forced swimming test.

    Science.gov (United States)

    Filho, Carlos B; Del Fabbro, Lucian; de Gomes, Marcelo G; Goes, André T R; Souza, Leandro C; Boeira, Silvana P; Jesse, Cristiano R

    2013-01-05

    The opioid system has been implicated as a contributing factor for major depression and is thought to play a role in the mechanism of action of antidepressants. This study investigated the involvement of the opioid system in the antidepressant-like effect of hesperidin in the mouse forced swimming test. Our results demonstrate that hesperidin (0.1, 0.3 and 1 mg/kg; intraperitoneal) decreased the immobility time in the forced swimming test without affecting locomotor activity in the open field test. The antidepressant-like effect of hesperidin (0.3 mg/kg) in the forced swimming test was prevented by pretreating mice with naloxone (1 mg/kg, a nonselective opioid receptor antagonist) and 2-(3,4-dichlorophenyl)-Nmethyl-N-[(1S)-1-(3-isothiocyanatophenyl)-2-(1-pyrrolidinyl)ethyl] acetamide (DIPPA (1 mg/kg), a selective κ-opioid receptor antagonist), but not with naloxone methiodide (1 mg/kg, a peripherally acting opioid receptor antagonist), naltrindole (3 mg/kg, a selective δ-opioid receptor antagonist), clocinnamox (1 mg/kg, a selective μ-opioid receptor antagonist) or caffeine (3 mg/kg, a nonselective adenosine receptor antagonist). In addition, a sub-effective dose of hesperidin (0.01 mg/kg) produced a synergistic antidepressant-like effect in the forced swimming test when combined with a sub-effective dose of morphine (1 mg/kg). The antidepressant-like effect of hesperidin in the forced swimming test on mice was dependent on its interaction with the κ-opioid receptor, but not with the δ-opioid, μ-opioid or adenosinergic receptors. Taken together, these results suggest that hesperidin possesses antidepressant-like properties and may be of interest as a therapeutic agent for the treatment of depressive disorders. Published by Elsevier B.V.

  12. Aerobic Swim Training Restores Aortic Endothelial Function by Decreasing Superoxide Levels in Spontaneously Hypertensive Rats

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    Camila P. Jordão

    Full Text Available OBJECTIVE: We aimed to determine whether aerobic training decreases superoxide levels, increases nitric oxide levels, and improves endothelium-dependent vasodilation in the aortas of spontaneously hypertensive rats. METHODS: Spontaneously hypertensive rats (SHR and Wistar Kyoto rats (WKY were distributed into 2 groups: sedentary (SHRsd and WKYsd, n=10 each and swimming-trained (SHRtr, n=10 and WKYtr, n=10, respectively. The trained group participated in training sessions 5 days/week for 1 h/day with an additional work load of 4% of the animal’s body weight. After a 10-week sedentary or aerobic training period, the rats were euthanized. The thoracic aortas were removed to evaluate the vasodilator response to acetylcholine (10-10 to 10-4 M with or without preincubation with L-NG-nitro-L-arginine methyl ester hydrochloride (L-NAME; 10-4 M in vitro. The aortic tissue was also used to assess the levels of the endothelial nitric oxide synthase and nicotinamide adenine dinucleotide oxidase subunit isoforms 1 and 4 proteins, as well as the superoxide and nitrite contents. Blood pressure was measured using a computerized tail-cuff system. RESULTS: Aerobic training significantly increased the acetylcholine-induced maximum vasodilation observed in the SHRtr group compared with the SHRsd group (85.9±4.3 vs. 71.6±5.2%. Additionally, in the SHRtr group, superoxide levels were significantly decreased, nitric oxide bioavailability was improved, and the levels of the nicotinamide adenine dinucleotide oxidase subunit isoform 4 protein were decreased compared to the SHRsd group. Moreover, after training, the blood pressure of the SHRtr group decreased compared to the SHRsd group. Exercise training had no effect on the blood pressure of the WKYtr group. CONCLUSIONS: In SHR, aerobic swim training decreased vascular superoxide generation by nicotinamide adenine dinucleotide oxidase subunit isoform 4 and increased nitric oxide bioavailability, thereby improving

  13. Anxiolytic effects of buspirone and MTEP in the Porsolt Forced Swim Test.

    Science.gov (United States)

    Lee, Kaziya M; Coelho, Michal A; Sern, Kimberly R; Class, MacKayla A; Bocz, Mark D; Szumlinski, Karen K

    2017-01-01

    Traditionally, a reduction in floating behavior or immobility in the Porsolt forced swim test (FST) is employed as a predictor of antidepressant efficacy. However, over the past several years, our studies of alcohol withdrawal-induced negative affect consistently indicate the coincidence of increased anxiety-related behaviors on various behavioral tests with reduced immobility in the FST. Further, this behavioral profile correlates with increased mGlu5 protein expression within limbic brain regions. As the role for mGlu5 in anxiety is well established, we hypothesized that the reduced immobility exhibited by alcohol-withdrawn mice when tested in the FST might reflect anxiety, possibly a hyper-reactivity to the acute swim stressor. Herein, we evaluated whether or not the decreased FST immobility during alcohol withdrawal responds to systemic treatment with a behaviorally-effective dose of the prototypical anxiolytic, buspirone (5 mg/kg). We also determined the functional relevance of the withdrawal-induced increase in mGlu5 expression for FST behavior by comparing the effects of buspirone to a behaviorally effective dose of the mGlu5 negative allosteric modulator MTEP (3 mg/kg). Adult male C57BL/6J mice were subjected to a 14-day, multi-bottle, binge-drinking protocol that elicits hyper-anxiety and increases glutamate-related protein expression during early withdrawal. Control animals received only water. At 24hr withdrawal, animals from each drinking condition were subdivided into groups and treated with an IP injection of buspirone, MTEP, or vehicle, 30min prior to the FST. Drug effects on general locomotor activity were also assessed. As we reported previously, alcohol-withdrawn animals exhibited significantly reduced immobility in the FST compared to water controls. Both buspirone and MTEP significantly increased immobility in alcohol-withdrawn animals, with a modest increase also seen in water controls. No significant group differences were observed for

  14. Effect of high-intensity intermittent swimming training on fatty acid oxidation enzyme activity in rat skeletal muscle.

    Science.gov (United States)

    Terada, Shin; Tabata, Izumi; Higuchi, Mitsuru

    2004-02-01

    We previously reported that high-intensity exercise training significantly increased citrate synthase (CS) activity, a marker of oxidative enzyme, in rat skeletal muscle to a level equaling that attained after low-intensity prolonged exercise training (Terada et al., J Appl Physiol 90: 2019-2024, 2001). Since mitochondrial oxidative enzymes and fatty acid oxidation (FAO) enzymes are often increased simultaneously, we assessed the effect of high-intensity intermittent swimming training on FAO enzyme activity in rat skeletal muscle. Male Sprague-Dawley rats (3 to 4 weeks old) were assigned to a 10-day period of high-intensity intermittent exercise training (HIT), low-intensity prolonged exercise training (LIT), or sedentary control conditions. In the HIT group, the rats repeated fourteen 20 s swimming sessions with a weight equivalent to 14-16% of their body weight. Between the exercise sessions, a 10 s pause was allowed. Rats in the LIT group swam 6 h/day in two 3 h sessions separated by 45 min of rest. CS activity in the triceps muscle of rats in the HIT and LIT groups was significantly higher than that in the control rats by 36 and 39%, respectively. Furthermore, 3-beta hydroxyacyl-CoA dehydrogenase (HAD) activity, an important enzyme in the FAO pathway in skeletal muscle, was higher in the two training groups than in the control rats (HIT: 100%, LIT: 88%). No significant difference in HAD activity was observed between the two training groups. In conclusion, the present investigation demonstrated that high-intensity intermittent swimming training elevated FAO enzyme activity in rat skeletal muscle to a level similar to that attained after 6 h of low-intensity prolonged swimming exercise training.

  15. The forced swimming-induced behavioural immobility response involves histone H3 phospho-acetylation and c-Fos induction in dentate gyrus granule neurons via activation of the N-methyl-D-aspartate/extracellular signal-regulated kinase/mitogen- and stress-activated kinase signalling pathway.

    Science.gov (United States)

    Chandramohan, Yalini; Droste, Susanne K; Arthur, J Simon C; Reul, Johannes M H M

    2008-05-01

    The hippocampus is involved in learning and memory. Previously, we have shown that the acquisition of the behavioural immobility response after a forced swim experience is associated with chromatin modifications and transcriptional induction in dentate gyrus granule neurons. Given that both N-methyl-D-aspartate (NMDA) receptors and the extracellular signal-regulated kinases (ERK) 1/2 signalling pathway are involved in neuroplasticity processes underlying learning and memory, we investigated in rats and mice whether these signalling pathways regulate chromatin modifications and transcriptional events participating in the acquisition of the immobility response. We found that: (i) forced swimming evoked a transient increase in the number of phospho-acetylated histone H3-positive [P(Ser10)-Ac(Lys14)-H3(+)] neurons specifically in the middle and superficial aspects of the dentate gyrus granule cell layer; (ii) antagonism of NMDA receptors and inhibition of ERK1/2 signalling blocked forced swimming-induced histone H3 phospho-acetylation and the acquisition of the behavioural immobility response; (iii) double knockout (DKO) of the histone H3 kinase mitogen- and stress-activated kinases (MSK) 1/2 in mice completely abolished the forced swimming-induced increases in histone H3 phospho-acetylation and c-Fos induction in dentate granule neurons and the behavioural immobility response; (iv) blocking mineralocorticoid receptors, known not to be involved in behavioural immobility in the forced swim test, did not affect forced swimming-evoked histone H3 phospho-acetylation in dentate neurons; and (v) the pharmacological manipulations and gene deletions did not affect behaviour in the initial forced swim test. We conclude that the forced swimming-induced behavioural immobility response requires histone H3 phospho-acetylation and c-Fos induction in distinct dentate granule neurons through recruitment of the NMDA/ERK/MSK 1/2 pathway.

  16. Propulsive force calculations in swimming frogs I. A momentum-impulse approach

    NARCIS (Netherlands)

    Nauwelaerts, S; Stamhuis, EJ; Aerts, P

    Frogs are animals that are capable of locomotion in two physically different media, aquatic and terrestrial. A comparison of the kinematics of swimming frogs in a previous study revealed a difference in propulsive impulse between jumping and swimming. To explore this difference further, we

  17. No evidence for a bioenergetic advantage from forced swimming in rainbow trout under a restrictive feeding regime

    Directory of Open Access Journals (Sweden)

    Peter Vilhelm Skov

    2015-02-01

    Full Text Available Sustained swimming at moderate speeds is considered beneficial in terms of the productive performance of salmonids, but the causative mechanisms have yet to be unequivocally established. In the present study, the effects of moderate exercise on the bioenergetics of rainbow trout were assessed during a 15 week growth experiment, in which fish were reared at three different current speeds: 1 BL s-1, 0.5 BL s-1 and still water (≈ 0 BL s-1. Randomly selected groups of 100 fish were distributed among twelve 600 L tanks and maintained on a restricted diet regime. Specific growth rate (SGR and feed conversion ratio (FCR were calculated from weight and length measurements every three weeks. Routine metabolic rate (RMR was measured every hour as rate of oxygen consumption in the tanks, and was positively correlated with swimming speed. Total ammonia nitrogen (TAN excretion rates showed a tendency to decrease with increasing swimming speeds, yet neither they nor the resulting nitrogen quotients (NQ indicated that swimming significantly reduced the fraction of dietary protein used to fuel metabolism. Energetic budgets revealed a positive correlation between energy expenditure and the current speed at which fish were reared, fish that were forced to swim and were fed restrictively consequentially had poorer growth and feed utilization. The results show that for rainbow trout, water current can negatively affect growth despite promoting minor positive changes in substrate utilization. We hypothesize that this may be the result of either a limited dietary energy supply from diet restriction being insufficient for both covering the extra costs of swimming and supporting enhanced growth.

  18. Learning and memory in the forced swimming test: effects of antidepressants having varying degrees of anticholinergic activity.

    Science.gov (United States)

    Enginar, Nurhan; Yamantürk-Çelik, Pınar; Nurten, Asiye; Güney, Dilvin Berrak

    2016-07-01

    The antidepressant-induced reduction in immobility time in the forced swimming test may depend on memory impairment due to the drug's anticholinergic efficacy. Therefore, the present study evaluated learning and memory of the immobility response in rats after the pretest and test administrations of antidepressants having potent, comparatively lower, and no anticholinergic activities. Immobility was measured in the test session performed 24 h after the pretest session. Scopolamine and MK-801, which are agents that have memory impairing effects, were used as reference drugs for a better evaluation of the memory processes in the test. The pretest administrations of imipramine (15 and 30 mg/kg), amitriptyline (7.5 and 15 mg/kg), trazodone (10 mg/kg), fluoxetine (10 and 20 mg/kg), and moclobemide (10 and 20 mg/kg) were ineffective, whereas the pretest administrations of scopolamine (0.5 mg/kg) and MK-801 (0.1 mg/kg) decreased immobility time suggesting impaired "learning to be immobile" in the animals. The test administrations of imipramine (30 mg/kg), amitriptyline (15 mg/kg), moclobemide (10 mg/kg), scopolamine (0.5 and 1 mg/kg), and MK-801 (0.1 mg/kg) decreased immobility time, which suggested that the drugs exerted antidepressant activity or the animals did not recall that attempting to escape was futile. The test administrations of trazodone (10 mg/kg) and fluoxetine (10 and 20 mg/kg) produced no effect on immobility time. Even though the false-negative and positive responses made it somewhat difficult to interpret the findings, this study demonstrated that when given before the pretest antidepressants with or without anticholinergic activity seemed to be devoid of impairing the learning process in the test.

  19. Sex and age differences in the antidepressant-like effect of fluoxetine in the forced swim test.

    Science.gov (United States)

    Fernández-Guasti, Alonso; Olivares-Nazario, Maribel; Reyes, Rebeca; Martínez-Mota, Lucía

    2017-01-01

    This study compared in males and females of three representative ages: young adults (3-5months old), middle-aged (12-15months old) and senescent (23-25months old) the antidepressant-like effect of fluoxetine (FLX, 5.0 and 10mg/kg) in the forced swim test (FST). Intact (non gonadectomized) rats were evaluated. Young adult females were chosen in proestrus/estrus or in metestrus/diestrus, while middle-aged and senescent females were selected in metestrus/diestrus. Locomotion and motor coordination were also recorded. Under basal conditions (without FLX), young adult and middle-aged females showed less immobility than males. This sex difference disappeared at senescence because males diminished their levels of immobility. Thus, senescent males showed lower immobility than middle-aged and young males. FLX (5 and 10mg/kg) produced similar actions in young females irrespective of their estrous cycle phase, therefore, these subgroups were pooled in a single one. Young adult and middle aged females clearly responded to 5 and 10mg/kg of FLX with a reduction in immobility, while young adult and middle-aged males only did to 10mg/kg. In senescent females 10mg/kg FLX reduced immobility. Remarkably, in senescent males this FLX dose did not produce an antidepressant-like effect. FLX marginally affected locomotion; however, at its highest dose (10mg/kg), and only in senescent males, interfered with motor coordination tested in the rotarod. These data show that sex and aging influence behavioral despair without treatment and after FLX. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Papaver Rhoeas L. Hydroalcoholic Extract Exacerbates Forced Swimming Test-Induced Depression in Mice.

    Science.gov (United States)

    Osanloo, Naser; Najafi-Abedi, Akram; Jafari, Fatemeh; Javid, Farshid; Pirpiran, Mohsen; Memar Jafari, Mohammad-Reza; Mousavi Khosravi, Seyed Ali; Rahimzadeh Behzadi, Mohammad; Ranjbaran, Mina; Sahraei, Hedayat

    2016-07-01

    Depression is one of the most frequent psychiatric disorders in the world with occurs with higher incidence in women. In the present study, the effect of water-alcoholic extract of Papaver rhoeas L. on forced swimming test (FST) in Swiss-Webster mice were examined. We used Swiss-Webster mice (20-25 g) to execute FST on them. The plant extract (1, 10, 30, and 100 mg/kg) was injected to the animals 30 minutes before each session. Fluoxetine (20 mg/kg) was used as standard antidepressant drug. In another group of animals, 30 minutes after extract administration, blood samples were taken from retro-orbital sinus for corticosterone assay. Yet in third group, the drugs were injected to the animals and 30 minutes later, their activities were tested in an open field apparatus. Our experiments showed that the extract efficiently reduced FST time both in male and female mice dose-dependently. This effect was comparable with fluoxetine. In addition, corticosterone assay indicated that plasma corticosterone in animals which received extract was higher than those amounts in fluoxetine and saline controls. Moreover, the animals did not show any motor activity deficit in all doses of the extract and fluoxetine compared to saline control. The extract of Papaver rhoeas can reduce immobility time which is comparable to the effect of fluoxetine. Also the effect of the extract is contrary to its effects on plasma corticosterone level and or animals' activity.

  1. Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test.

    Science.gov (United States)

    Kotagale, Nandkishor R; Tripathi, Sunil J; Aglawe, Manish M; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

    2013-06-01

    Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Evidence for the involvement of extinction-associated inhibitory learning in the forced swimming test.

    Science.gov (United States)

    Campus, P; Colelli, V; Orsini, C; Sarra, D; Cabib, S

    2015-02-01

    The forced swimming test (FST) remains one of the most used tools for screening antidepressants in rodent models. Nonetheless, the nature of immobility, its main behavioral measure, is still a matter of debate. The present study took advantage of our recent finding that mice of the inbred DBA/2J strain require a functioning left dorsolateral striatum (DLS) to consolidate long-term memory of FST to test whether immobility is the outcome of stress-related learning. Infusion of the GABA-A agonist muscimol in the left DLS immediately after a single experience of FST prevented and infusion in the left or the right amygdala impaired recall of the acquired levels of immobility in a probe test performed 24h later. Post-training left DLS infusion of muscimol, at a dose capable of preventing retention of FST-induced immobility, did not influence 24h retention of inhibitory avoidance training or of the escape response acquired in a water T-maze. However, this same treatment prevented 24h retention of the extinction training of the consolidated escape response. These results indicate that a left DLS-centered memory system selectively mediates memory consolidation of FST and of escape extinction and support the hypothesis that immobility is the result of extinction-like inhibitory learning involving all available escape responses due to the inescapable/unavoidable nature of FST experience. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Swimming exercise enhances the hippocampal antioxidant status of female Wistar rats.

    Science.gov (United States)

    Stone, Vinícius; Kudo, Karen Yurika; Marcelino, Thiago Beltram; August, Pauline Maciel; Matté, Cristiane

    2015-05-01

    Moderate exercise is known to have health benefits, while both sedentarism and strenuous exercise have pro-oxidant effects. In this study, we assessed the effect of moderate exercise on the antioxidant homeostasis of rats' hippocampi. Female Wistar rats were submitted to a 30-minute swimming protocol on 5 days a week, for 4 weeks. Control rats were immersed in water and carefully dried. Production of hippocampal reactive species, activity of antioxidant enzymes, and glutathione levels in these animals were determined up to 30 days after completion of the 4-week protocol. Production of reactive species and hippocampal glutathione levels were increased 1 day after completion of the 4-week protocol, and returned to control levels after 7 days. Antioxidant enzyme activities were increased both 1 day (catalase) and 7 days (superoxide dismutase and glutathione peroxidase) after completion of the protocol. Thirty days after completion of the protocol, none of the antioxidant parameters evaluated differed from those of controls. Our results reinforce the benefits of aerobic exercise, which include positive modulation of antioxidant homeostasis in the hippocampi. The effects of exercise are not permanent; rather, an exercise regimen must be continued in order to maintain the neurometabolic adaptations.

  4. Effects of periadolescent fluoxetine and paroxetine on elevated plus-maze, acoustic startle, and swimming immobility in rats while on and off-drug.

    Science.gov (United States)

    Vorhees, Charles V; Morford, LaRonda R; Graham, Devon L; Skelton, Matthew R; Williams, Michael T

    2011-10-05

    Whether selective serotonin reuptake inhibitors (SSRIs) exposure during adolescent brain development causes lasting effects remains unresolved. Assess the effects of fluoxetine and paroxetine 60 days after adolescent exposure compared with when on-drug. Male Sprague-Dawley littermates (41 litters) were gavaged on postnatal days 33-53 with fluoxetine (3 or 10 mg/kg/day), paroxetine (3, 10 or, 17 mg/kg/day), or water; half were tested while on-drug (21 litters) and half after 60 days off-drug (20 litters). The highest dose of the drugs reduced body weight gain during treatment that rebounded 1 week post-treatment. On-drug, no significant group differences were found on elevated plus maze time-in-open, zone entries, or latency to first open entry; however, the high dose of paroxetine significantly reduced head-dips (N=20/group). No significant effects were found on-drug for acoustic startle response/prepulse inhibition (ASR/PPI) although a trend (pfluoxetine and paroxetine (N=20-21/group). No differences on immobility time were seen in the Porsolt forced swim test or in plasma corticosterone at the end of forced swim (N-19-21/group). Off-drug, no effects were seen in the elevated plus maze (N=16/group), ASR/PPI (N=20/group), forced swim (N=19-20/group), or plasma corticosterone (N=19/group). At the doses tested, fluoxetine and paroxetine induced minor effects with drug on-board but no residual, long-term adverse effects in rats 60 days after drug discontinuation. The data provide no evidence that fluoxetine or paroxetine have long-term adverse effects on the behaviors measured here after adolescent to young adult exposure.

  5. Swim Training Improves HOMA-IR in Type 2 Diabetes Induced by High Fat Diet and Low Dose of Streptozotocin in Male Rats.

    Science.gov (United States)

    Ghiasi, Rafigheh; Ghadiri Soufi, Farhad; Somi, Mohammad Hossein; Mohaddes, Gisou; Mirzaie Bavil, Fariba; Naderi, Roya; Alipour, Mohammad Reza

    2015-09-01

    Insulin resistance plays a key role in the onset and development of type 2 diabetes mellitus (T2DM) and its complications. In this study, we evaluated the effect of swim training on insulin resistance in diabetic rats. Forty male Wistar rats were randomly divided into four groups (n=10): sedentary control (Con), sedentary diabetic (Dia), swim trained control (Exe) and swim trained diabetic (Dia+Exe) rats. Diabetes was induced by high fat diet (HFD) and a low dose of streptozotocin (35 mg/kg, i.p). In trained groups, one week after the induction of diabetes, animals were subjected to swimming (60 min/5 days a week) for 10 weeks. At the end of training, fasting blood sugar (FBS), oral glucose tolerance test (OGTT), fasting/basal insulin, glycosylated hemoglobin (HbA1c) levels, insulin resistance index, homeostasis model assessment method (HOMA-IR), triglycerides (TG,) total cholesterol (TCh), and high density lipoprotein (HDL) levels in blood were measured. Swimming significantly improved OGTT (PHOMA-IR (P<0.01). Swim training also significantly decreased FBS (p<0.01), fasting/basal insulin (P<0.01), HbA1C (p<0.01), TG (P<0.05), and TCh (P<0.05) levels. It also significantly increased HDL (p<0.05) level. Our findings indicate that swim training improved glycemic control and insulin sensitivity in type 2 diabetes caused by high fat diet in male rats.

  6. Swimming exercise increases serum irisin level and reduces body fat mass in high-fat-diet fed Wistar rats.

    Science.gov (United States)

    Lu, Yun; Li, Hongwei; Shen, Shi-Wei; Shen, Zhen-Hai; Xu, Ming; Yang, Cheng-Jian; Li, Feng; Feng, Yin-Bo; Yun, Jing-Ting; Wang, Ling; Qi, Hua-Jin

    2016-05-13

    It has been shown that irisin levels are reduced in skeletal muscle and plasma of obese rats; however, the effect of exercise training on irisin level remains controversial. We aim to evaluate the association of swimming exercise with serum irisin level and other obesity-associated parameters. Forty healthy male Wistar rats were randomly assigned to 4 groups: a normal diet and sedentary group (ND group), normal diet and exercise group (NDE group), high-fat diet and sedentary group (HFD group), and high-fat diet and exercise group (HFDE group. After 8 consecutive weeks of swimming exercise, fat mass and serum irisin level was determined. Higher serum irisin levels were detected in the HFDE group (1.15 ± 0.28 μg/L) and NDE group (1.76 ± 0.17 μg/L) than in the HFD group (0.84 ± 0.23 μg/L) or the ND group (1.24 ± 0.29 μg/L), respectively (HFDE group vs. HFD group, P mass (r = -0.68, P mass (r = -0.576, P mass (r = -0.439, P mass, visceral fat mass and percentage fat mass were lower in the HFDE group than the HFD group (all P values mass in high-fat-fed Wistar rats, which may be attributable to elevated irisin levels induced by swimming exercise.

  7. Ethanol induced antidepressant-like effect in the mouse forced swimming test: modulation by serotonergic system.

    Science.gov (United States)

    Jain, Nishant S; Kannamwar, Uday; Verma, Lokesh

    2017-02-01

    The present investigation explored the modulatory role of serotonergic transmission in the acute ethanol-induced effects on immobility time in the mouse forced swim test (FST). Acute i.p. administration of ethanol (20% w/v, 2 or 2.5 g/kg, i.p.) decreased the immobility time in FST of mice, indicating its antidepressant-like effect while lower doses of ethanol (1, 1.5 g/kg, i.p.) were devoid of any effect in the FST. The mice pre-treated with a sub-effective dose of 5-HT 2A agonist, DOI (10 μg/mouse, i.c.v.) or 5-HT 1A receptor antagonist, WAY 100635 (0.1 μg/mouse, i.c.v.) but not with the 5-HT 2A/2C antagonist, ketanserin (1.5 μg/mouse, i.c.v.) exhibited a synergistic reduction in the immobility time induced by sub-effective dose of ethanol (1.5 g/kg, i.p.). On the other hand, ethanol (2.5 g/kg, i.p.) failed to decrease the immobility time in mice, pre-treated with 5-HT 1A agonist, 8-OH-DPAT (0.1 μg/mouse, i.c.v.) or ketanserin (1.5 μg/mouse, i.c.v.). In addition, pre-treatment with a 5-HT neuronal synthesis inhibitor, p-CPA (300 mg/kg, i.p. × 3 days) attenuated the anti-immobility effect ethanol (2.5 g/kg, i.p.) in mouse FST. Thus, the results of the present study points towards the essentiality of the central 5-HT transmission at the synapse for the ethanol-induced antidepressant-like effect in the FST wherein the regulatory role of the 5-HT 1A receptor or contributory role of the 5-HT 2A/2C receptor-mediated mechanism is proposed in the anti-immobility effect of acute ethanol in mouse FST.

  8. Antidepressant-like effect of oleanolic acid in mice exposed to the repeated forced swimming test.

    Science.gov (United States)

    Yi, Li-Tao; Li, Jing; Liu, Qing; Geng, Di; Zhou, Ya-Fei; Ke, Xiao-Qing; Chen, Huan; Weng, Lian-Jin

    2013-05-01

    The study aimed to explore the antidepressant-like effect of oleanolic acid and its possible mechanism related to the monoaminergic system and neurotrophin in mice exposed to the repeated forced swimming test (FST). Both the duration and the latency of immobility affected by oleanolic acid (10, 20 and 40 mg/kg) were evaluated in the FST repeated at intervals on days 1, 7 and 14, followed by neurochemical and brain-derived neurotrophic factor (BDNF) analyses in the mouse brain regions of frontal cortex and whole hippocampus. A repeated analysis of variance (ANOVA) indicated that over retesting the immobility time increased, whereas latency to immobility tended to decrease. Minute-by-minute analysis showed that immobility time also increased during the 4-min course of the test. In addition, post-hoc Dunnett's test demonstrated that sub-chronic and chronic, but not acute, oleanolic acid treatment reduced the immobility time (sub-chronic: 20 mg/kg, 43.5%; chronic: 10 mg/kg, 19.3%; 20 mg/kg, 31.8%) and increased the latency to immobility (sub-chronic: 10 mg/kg, 60.6%; 20 mg/kg, 80.1%; chronic: 10 mg/kg, 121.8%; 20 mg/kg, 140.8%; 40 mg/kg, 80.0%). Furthermore, chronic administration of oleanolic acid significantly increased serotonin (5-HT) levels (frontal cortex: 44.5%, 41.9%, 27.5% for 10, 20, 40 mg/kg; hippocampus: 57.2%, 80.9% for 10, 20 mg/kg), decreased 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio (frontal cortex: 31.6%, 30.1%, 23.5%; hippocampus: 40.6%, 47.7%, 29.2% for 10, 20, 40 mg/kg) and elevated norepinephrine (NE) levels (hippocampus: 20 mg/kg, 45.4%) but did not alter dopamine (DA) levels. Moreover, BDNF levels in the two brain regions were also elevated by chronic oleanolic acid treatment (frontal cortex: 20 mg/kg, 67.2%; hippocampus: 10 mg/kg, 36.4%; 20 mg/kg, 55.1%). Taken together, these findings imply that functions of 5-HT, NE and BDNF may be involved in the antidepressant-like effect of oleanolic acid.

  9. Boxfish swimming paradox resolved : forces by the flow of water around the body promote manoeuvrability

    NARCIS (Netherlands)

    Van Wassenbergh, S.; van Manen, K.; Marcroft, T. A.; Alfaro, M. E.; Stamhuis, E. J.

    2015-01-01

    The shape of the carapace protecting the body of boxfishes has been attributed an important hydrodynamic role in drag reduction and in providing automatic, flow-direction realignment and is therefore used in bioinspired design of cars. However, tight swimming-course stabilization is paradoxical

  10. Differential behavioral effects of the antidepressants reboxetine, fluoxetine, and moclobemide in a modified forced swim test following chronic treatment.

    Science.gov (United States)

    Cryan, John F; Page, Michelle E; Lucki, Irwin

    2005-11-01

    The forced swim test (FST) is the most widely used model for assessing potential antidepressant activity in rodents following acute or short-term treatment. However, few studies have compared the effects of short- and long-term antidepressant treatment on behaviors in the test, despite the need to treat patients chronically to produce clinical effects. The current studies examined whether antidepressants from different classes produce different behavioral effects following short-term treatment and whether such effects change following administration for a longer duration. The effects of administering short-term (3 days) and long-term (14 days) treatments of antidepressants from three different chemical classes with distinct mechanisms of action via osmotic minipump were examined: the selective norepinephrine reuptake inhibitor reboxetine (10 and 60 mg kg(-1) day(-1)), the selective serotonin reuptake inhibitor fluoxetine (2.5 and 15 mg kg(-1) day(-1)), and the reversible inhibitor of monoamine oxidase moclobemide (2.5 and 15 mg kg(-1) day(-1)). All testing was carried out in a 15-min test with no preswim session in order to negate any confounding aspect of an induction procedure. The majority of antidepressant-sensitive behavioral changes were observed in the first 5 min of the test. The low dose of reboxetine failed to alter behavior in the test after 3 days but significantly decreased immobility and increased climbing behavior following administration for 14 days, whereas the high dose of reboxetine was equally effective following 3 and 14 days of treatment. In a similar fashion, the low dose of fluoxetine failed to alter behavior in the test following 3 days, but showed an augmented response on immobility and increased swimming following administration for 14 days. The high dose of fluoxetine was slightly more effective at reducing immobility following administration for 14 days than 3 days. The low dose of moclobemide decreased immobility and increased climbing

  11. Effects of high-intensity swimming training on GLUT-4 and glucose transport activity in rat skeletal muscle.

    Science.gov (United States)

    Terada, S; Yokozeki, T; Kawanaka, K; Ogawa, K; Higuchi, M; Ezaki, O; Tabata, I

    2001-06-01

    This study was performed to assess the effects of short-term, extremely high-intensity intermittent exercise training on the GLUT-4 content of rat skeletal muscle. Three- to four-week-old male Sprague-Dawley rats with an initial body weight ranging from 45 to 55 g were used for this study. These rats were randomly assigned to an 8-day period of high-intensity intermittent exercise training (HIT), relatively high-intensity intermittent prolonged exercise training (RHT), or low-intensity prolonged exercise training (LIT). Age-matched sedentary rats were used as a control. In the HIT group, the rats repeated fourteen 20-s swimming bouts with a weight equivalent to 14, 15, and 16% of body weight for the first 2, the next 4, and the last 2 days, respectively. Between exercise bouts, a 10-s pause was allowed. RHT consisted of five 17-min swimming bouts with a 3-min rest between bouts. During the first bout, the rat swam without weight, whereas during the following four bouts, the rat was attached to a weight equivalent to 4 and 5% of its body weight for the first 5 days and the following 3 days, respectively. Rats in the LIT group swam 6 h/day for 8 days in two 3-h bouts separated by 45 min of rest. In the first experiment, the HIT, LIT, and control rats were compared. GLUT-4 content in the epitrochlearis muscle in the HIT and LIT groups after training was significantly higher than that in the control rats by 83 and 91%, respectively. Furthermore, glucose transport activity, stimulated maximally by both insulin (2 mU/ml) (HIT: 48%, LIT: 75%) and contractions (25 10-s tetani) (HIT: 55%, LIT: 69%), was higher in the training groups than in the control rats. However, no significant differences in GLUT-4 content or in maximal glucose transport activity in response to both insulin and contractions were observed between the two training groups. The second experiment demonstrated that GLUT-4 content after HIT did not differ from that after RHT (66% higher in trained rats than

  12. Chelidonic acid evokes antidepressant-like effect through the up-regulation of BDNF in forced swimming test.

    Science.gov (United States)

    Jeong, Hyun-Ja; Yang, Shi-Young; Kim, Hee-Yun; Kim, Na-Rae; Jang, Jae-Bum; Kim, Hyung-Min

    2016-08-01

    Depression is usually accompanied by neuro-inflammatory reactions. Chelidonic acid, in particular, has shown anti-inflammatory effects. The objective of this study was to evaluate the anti-depressant effects of chelidonic acid and to discuss the potential mechanisms of a forced swimming test. Chelidonic acid was administered orally once a day for 14 days. On the 14th day, chelidonic acid resulted in a significant decrease in immobility time during the forced swimming test without alteration of locomotor activity, in an open field test. Chelidonic acid also increased the number of nissl bodies in the hippocampus. Brain-derived neurotrophic factor expression and extracellular signal-regulated protein kinase phosphorylation in the hippocampus were up-regulated by the administration of chelidonic acid. Chelidonic acid administration significantly increased the mRNA expression of hippocampal estrogen receptor-β. The levels of hippocampal interleukin (IL)-1β, IL-6, and tumor necrosis factor-α were effectively attenuated by the administration of chelidonic acid. In addition, chelidonic acid significantly increased the levels of 5-hydroxytryptamine (serotonin), dopamine, and norepinephrine compared with those levels for the mice that were administered distilled water in the hippocampus. These results suggest that chelidonic acid might serve as a new therapeutic strategy for the regulation of depression associated with inflammation. © 2016 by the Society for Experimental Biology and Medicine.

  13. Antidepressant-like effect of harmane and other beta-carbolines in the mouse forced swim test.

    Science.gov (United States)

    Farzin, Davood; Mansouri, Nazanin

    2006-07-01

    The purpose of the present study was to determine the effects of harmane, norharmane and harmine on the immobility time in the mouse forced swim test (FST) - an animal model of depression. After 30 min of the beta-carbolines injections, mice were placed individually in a vertical glass cylinder (height, 25 cm; diameter, 12 cm) containing water about 15 cm deep at 22+/-1 degrees C and forced to swim. Treatment of animals with harmane (5-15 mg/kg, i.p.), norharmane (2.5-10 mg/kg, i.p.) and harmine (5-15 mg/kg, i.p.) reduced dose-dependently the time of immobility. Their antidepressant-like effects were not affected by pretreatment with reserpine at the dose of 5 mg/kg, i.p., 18 h before the test, which did not modify the immobility time. Conversely, when flumazenil (5 mg/kg, i.p.) was administered 30 min before the test, it was able to antagonize completely the antidepressant-like effects of harmane, norharmane and harmine. It was concluded that harmane, norharmane and harmine reduce the immobility time in this test, suggesting an antidepressant-like effect, via an inverse-agonistic mechanism located in the benzodiazepine receptors.

  14. Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.

    Science.gov (United States)

    Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Cho, Jin Hee; Cho, Yun Ha; Kim, Dong-Hoon; Shin, Kyung Ho

    2014-10-01

    Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The Impacts of Swimming Exercise on Hippocampal Expression of Neurotrophic Factors in Rats Exposed to Chronic Unpredictable Mild Stress

    Directory of Open Access Journals (Sweden)

    Pei Jiang

    2014-01-01

    Full Text Available Depression is associated with stress-induced neural atrophy in limbic brain regions, whereas exercise has antidepressant effects as well as increasing hippocampal synaptic plasticity by strengthening neurogenesis, metabolism, and vascular function. A key mechanism mediating these broad benefits of exercise on the brain is induction of neurotrophic factors, which instruct downstream structural and functional changes. To systematically evaluate the potential neurotrophic factors that were involved in the antidepressive effects of exercise, in this study, we assessed the effects of swimming exercise on hippocampal mRNA expression of several classes of the growth factors (BDNF, GDNF, NGF, NT-3, FGF2, VEGF, and IGF-1 and peptides (VGF and NPY in rats exposed to chronic unpredictable mild stress (CUMS. Our study demonstrated that the swimming training paradigm significantly induced the expression of BDNF and BDNF-regulated peptides (VGF and NPY and restored their stress-induced downregulation. Additionally, the exercise protocol also increased the antiapoptotic Bcl-xl expression and normalized the CUMS mediated induction of proapoptotic Bax mRNA level. Overall, our data suggest that swimming exercise has antidepressant effects, increasing the resistance to the neural damage caused by CUMS, and both BDNF and its downstream neurotrophic peptides may exert a major function in the exercise related adaptive processes to CUMS.

  16. Effect of desipramine and citalopram treatment on forced swimming test-induced changes in cocaine- and amphetamine-regulated transcript (CART) immunoreactivity in mice.

    Science.gov (United States)

    Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Kim, Jin Wook; Kim, Jeong Min; Shin, Kyung Ho

    2014-05-01

    Recent study demonstrates antidepressant-like effect of cocaine- and amphetamine-regulated transcript (CART) in the forced swimming test (FST), but less is known about whether antidepressant treatments alter levels of CART immunoreactivity (CART-IR) in the FST. To explore this possibility, we assessed the treatment effects of desipramine and citalopram, which inhibit the reuptake of norepinephrine and serotonin into the presynaptic terminals, respectively, on changes in levels of CART-IR before and after the test swim in mouse brain. Levels of CART-IR in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), and hypothalamic paraventricular nucleus (PVN) were significantly increased before the test swim by desipramine and citalopram treatments. This increase in CART-IR in the AcbSh, dBNST, and PVN before the test swim remained elevated by desipramine treatment after the test swim, but this increase in these brain areas returned to near control levels after test swim by citalopram treatment. Citalopram, but not desipramine, treatment increased levels of CART-IR in the central nucleus of the amygdala (CeA) and the locus ceruleus (LC) before the test swim, and this increase was returned to control levels after the test swim in the CeA, but not in the LC. These results suggest common and distinct regulation of CART by desipramine and citalopram treatments in the FST and raise the possibility that CART in the AcbSh, dBNST, and CeA may be involved in antidepressant-like effect in the FST.

  17. Identification of multiple genetic loci in the mouse controlling immobility time in the tail suspension and forced swimming tests.

    Science.gov (United States)

    Abou-Elnaga, Ahmed F; Torigoe, Daisuke; Fouda, Mohamed M; Darwish, Ragab A; Abou-Ismail, Usama A; Morimatsu, Masami; Agui, Takashi

    2015-05-01

    Depression is one of the most famous psychiatric disorders in humans in all over the countries and considered a complex neurobehavioral trait and difficult to identify causal genes. Tail suspension test (TST) and forced swimming test (FST) are widely used for assessing depression-like behavior and antidepressant activity in mice. A variety of antidepressant agents are known to reduce immobility time in both TST and FST. To identify genetic determinants of immobility duration in both tests, we analyzed 101 F2 mice from an intercross between C57BL/6 and DBA/2 strains. Quantitative trait locus (QTL) mapping using 106 microsatellite markers revealed three loci (two significant and one suggestive) and five suggestive loci controlling immobility time in the TST and FST, respectively. Results of QTL analysis suggest a broad description of the genetic architecture underlying depression, providing underpinnings for identifying novel molecular targets for antidepressants to clear the complex genetic mechanisms of depressive disorders.

  18. Involvement of central opioid systems in human interferon-α induced immobility in the mouse forced swimming test

    Science.gov (United States)

    Makino, Mitsuhiro; Kitano, Yutaka; Komiyama, Chika; Hirohashi, Masaaki; Takasuna, Kiyoshi

    2000-01-01

    We investigated the mechanism by which human interferon-α (IFN-α) increases the immobility time in a forced swimming test, an animal model of depression.Central administration of IFN-α (0.05–50 IU per mouse, i.cist.) increased the immobility time in the forced swimming test in mice in a dose-dependent manner.Neither IFN-β nor -γ possessed any effect under the same experimental conditions.Pre-treatment with an opioid receptor antagonist, naloxone (1 mg kg−1, s.c.) inhibited the prolonged immobility time induced by IFN-α (60 KIU kg−1, i.v. or 50 IU per mouse. i.cist.).Peripheral administration of naloxone methiodide (1 mg kg−1, s.c.), which does not pass the blood–brain barrier, failed to block the effect of IFN-α, while intracisternal administration of naloxone methiodide (1 nmol per mouse) completely blocked.The effect of IFN-α was inhibited by a μ1-specific opioid receptor antagonist, naloxonazine (35 mg kg−1, s.c.) and a μ1/μ2 receptor antagonist, β-FNA (40 mg kg−1, s.c.). A selective δ-opioid receptor antagonist, naltrindole (3 mg kg−1, s.c.) and a κ-opioid receptor antagonist, nor-binaltorphimine (20 mg kg−1, s.c.), both failed to inhibit the increasing effect of IFN-α.These results suggest that the activator of the central opioid receptors of the μ1-subtype might be related to the prolonged immobility time of IFN-α, but δ and κ-opioid receptors most likely are not involved. PMID:10903965

  19. The effect of acute swim stress and training in the water maze on hippocampal synaptic activity as well as plasticity in the dentate gyrus of freely moving rats: revisiting swim-induced LTP reinforcement.

    Science.gov (United States)

    Tabassum, Heena; Frey, Julietta U

    2013-12-01

    Hippocampal long-term potentiation (LTP) is a cellular model of learning and memory. An early form of LTP (E-LTP) can be reinforced into its late form (L-LTP) by various behavioral interactions within a specific time window ("behavioral LTP-reinforcement"). Depending on the type and procedure used, various studies have shown that stress differentially affects synaptic plasticity. Under low stress, such as novelty detection or mild foot shocks, E-LTP can be transformed into L-LTP in the rat dentate gyrus (DG). A reinforcing effect of a 2-min swim, however, has only been shown in (Korz and Frey (2003) J Neurosci 23:7281-7287; Korz and Frey (2005) J Neurosci 25:7393-7400; Ahmed et al. (2006) J Neurosci 26:3951-3958; Sajikumar et al., (2007) J Physiol 584.2:389-400) so far. We have reinvestigated these studies using the same as well as an improved recording technique which allowed the recording of field excitatory postsynaptic potentials (fEPSP) and the population spike amplitude (PSA) at their places of generation in freely moving rats. We show that acute swim stress led to a long-term depression (LTD) in baseline values of PSA and partially fEPSP. In contrast to earlier studies a LTP-reinforcement by swimming could never be reproduced. Our results indicate that 2-min swim stress influenced synaptic potentials as well as E-LTP negatively. Copyright © 2013 Wiley Periodicals, Inc.

  20. Differences in the effects of 5-HT1A receptor agonists on forced swimming behavior and brain 5-HT metabolism between low and high aggressive mice

    NARCIS (Netherlands)

    Veenema, AH; Cremers, TIFH; Jongsma, ME; Steenbergen, PJ; de Boer, SF; Koolhaas, JM; Jongsma, Minke E.

    Rationale: Male wild house- mice genetically selected for long attack latency ( LAL) and short attack latency ( SAL) differ in structural and functional properties of postsynaptic serotonergic- 1A ( 5- HT1A) receptors. These mouse lines also show divergent behavioral responses in the forced swimming

  1. Effect of endurance swimming on rat cardiac myofibrillar ATPase with experimental diabetes.

    Science.gov (United States)

    Belcastro, A N; Maybank, P; Rossiter, M; Secord, D

    1985-09-01

    Diabetes is characterized by depressed cardiac functional properties attributed to Ca2+-activated ATPase activity. In contrast, endurance swimming enhances the cardiac functional properties and Ca2+-activated myofibril ATPase. Thus, the purpose of this study was to observe if the changes associated with experimental diabetes can be ameliorated with training. Diabetes was induced with a single i.v. injection of streptozotocin (60 mg/kg). Blood and urine glucose concentrations were 802 +/- 44 and 6965 +/- 617 mg/dL, respectively. The training control and training diabetic animals were made to swim (+/- 2% body weight) 4 days/week for 8 weeks. Cardiac myofibril, at 10 microM free Ca2+ concentration was reduced by 54% in the sedentary diabetics compared with sedentary control animals (p less than 0.05). Swim training enhanced the Ca2+-activated myofibril ATPase activities for the normal animals. The diabetic animals, which swam for 8 weeks, had further reduced their Ca2+-activated myofibril ATPase activity when compared with sedentary diabetics (p less than 0.05). Similarly, the Mg2+-stimulated myofibril ATPase activity was depressed by 31% in diabetics following endurance swimming. It is concluded that the depressed Ca2+-activated myofibril ATPase activity of diabetic hearts is not reversible with endurance swimming.

  2. Role of different types of potassium channels in the antidepressant-like effect of agmatine in the mouse forced swimming test.

    Science.gov (United States)

    Budni, Josiane; Gadotti, Vinícius M; Kaster, Manuella P; Santos, Adair R S; Rodrigues, Ana Lúcia S

    2007-12-01

    The administration of agmatine elicits an antidepressant-like effect in the mouse forced swimming test by a mechanism dependent on the inhibition of the NMDA receptors and the L-arginine-nitric oxide (NO) pathway. Since it has been reported that the NO can activate different types of potassium (K(+)) channels in several tissues, the present study investigates the possibility of synergistic interactions between different types of K(+) channel inhibitors and agmatine in the forced swimming test. Treatment of mice by i.c.v. route with subeffective doses of tetraethylammonium (a non specific inhibitor of K(+) channels, 25 pg/site), glibenclamide (an ATP-sensitive K(+) channels inhibitor, 0.5 pg/site), charybdotoxin (a large- and intermediate-conductance calcium-activated K(+) channel inhibitor, 25 pg/site) or apamin (a small-conductance calcium-activated K(+) channel inhibitor, 10 pg/site), augmented the effect of agmatine (0.001 mg/kg, i.p.) in the forced swimming test. Furthermore, the administration of agmatine and the K(+) channel inhibitors, alone or in combination, did not affect locomotion in the open-field test. Moreover, the reduction in the immobility time elicited by an active dose of agmatine (10 mg/kg, i.p.) in the forced swimming test was prevented by the pre-treatment of mice with the K(+) channel openers cromakalim (10 microg/site, i.c.v.) and minoxidil (10 microg/site, i.c.v.), without affecting locomotion. Together these data raise the possibility that the antidepressant-like effect of agmatine in the forced swimming test is related to its modulatory effects on neuronal excitability, via inhibition of K(+) channels.

  3. Rutin, a flavonoid and principal component of saussurea involucrata, attenuates physical fatigue in a forced swimming mouse model.

    Science.gov (United States)

    Su, Kang-Yi; Yu, Chao Yuan; Chen, Yue-Wen; Huang, Yi-Tsau; Chen, Chun-Ting; Wu, Hsueh-Fu; Chen, Yi-Lin Sophia

    2014-01-01

    This study investigated the antifatigue effects of rutin, a flavonoid extracted from the ethyl acetate extract of S. involucrata. Mice were subjected to a weight-loaded forced swim test (WFST) on alternate days for 3 wk. Rutin was administered orally to the mice for 7 days in dosages of 15, 30, and 60 mg/kg body weight, and several biomarkers of physical fatigue were evaluated: swimming time, change in body weight, lipid peroxidation, lactic acid (LA), glycogen, and the activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx). On Day 7, the rutin-treated mice had a 3-fold longer exhaustive swimming time than the control mice, as well as significantly reduced blood LA concentrations. The 15, 30, and 60 mg/kg body weight rutin-supplemented groups displayed 11.2%, 22.5%, and 37.7% reduced malondialdehyde (MDA) concentrations, respectively, in brain and muscle tissues compared with the control exercised group. Our results indicated that the administration of rutin protected the mice against the depletion of SOD and GPx activities significantly. Following 7 days of rutin treatment, we sacrificed the mice and analyzed their soleus muscle and brain for peroxisome proliferator-activated receptor-α coactivator (PGC-1α) and sirtuin 1 (SIRT1) mRNA expression. We observed that rutin treatment increased PGC-1α and SIRT1 mRNA and protein expression. The changes in these markers of mitochondrial biogenesis were associated with increased maximal endurance capacity. The application of 2D gel electrophoresis to analyze the rutin-responsive protein profiles in the WFST mouse brain further revealed the upregulation of the CB1 cannabinoid receptor-interacting protein 1, myelin basic protein, Rho GDP dissociation inhibitor (GDI) alpha, and TPI, indicating that rutin might inhibit anxiety through the upregulation of the expression of anxiety-associated proteins. Western blot analysis of MAPK expression further confirmed the antianxiety effects

  4. Diminished hormonal responses to exercise in trained rats

    DEFF Research Database (Denmark)

    Galbo, H; Richter, Erik; Holst, J J

    1977-01-01

    Male rats (120 g) either were subjected to a 12-wk physical training program (T rats) or were sedentary controls (C rats). Subsequently the rats were killed at rest or after a 45- or 90-min forced swim. At rest, T rats had higher liver and muscle glycogen concentrations but lower plasma insulin...

  5. Effect of Withania somnifera on forced swimming test induced immobility in mice and its interaction with various drugs.

    Science.gov (United States)

    Shah, P C; Trivedi, N A; Bhatt, J D; Hemavathi, K G

    2006-01-01

    The objective of the present study was to evaluate the antidepressant action of Withania somnifera (WS) as well as its interaction with the conventional antidepressant drugs and to delineate the possible mechanism of its antidepressant action using forced swimming model in mice. Effect of different doses of WS, fluoxetine and imipramine were studied on forced swimming test induced mean immobility time (MIT). Moreover effect of WS 100 mg/kg, i.p. was observed at different time intervals. Effect produced by combination of sub therapeutic doses of WS with imipramine (2.5 mg/kg, i.p.) as well as fluoxetine (2.5 mg/kg, i.p.) were also observed. Effect of WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) were observed in mice pretreated with reserpine (2 mg/kg, i.p.) and clonidine (0.15 mg/kg, i.p.). Effects of prazosin (3 mg/kg, i.p.) or haloperidol (0.1 mg/kg, i.p.) pre-treatment were also observed on WS induced decrease in MIT. WS produced dose dependent decrease in MIT. Maximum effect in MIT was observed after 30 min of treatment with WS 100 mg/kg, i.p. Combination of WS (37.5 mg/kg, i.p.) with imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) also produced significant decrease in the MIT. Clonidine and reserpine induced increase in MIT, was significantly reversed by treatment with WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.). Pre-treatment with prazosin but not haloperidol, significantly antagonized the WS (100 mg/kg, i.p.) induced decrease in MIT. It is concluded that, WS produced significant decrease in MIT in mice which could be mediated partly through a adrenoceptor as well as alteration in the level of central biogenic amines.

  6. Investigation of flow mechanism of a robotic fish swimming by using flow visualization synchronized with hydrodynamic force measurement

    Science.gov (United States)

    Tan, Guang-Kun; Shen, Gong-Xin; Huang, Shuo-Qiao; Su, Wen-Han; Ke, Yu

    When swimming in water by flapping its tail, a fish can overcome the drag from uniform flow and propel its body. The involved flow mechanism concerns 3-D and unsteady effects. This paper presents the investigation of the flow mechanism on the basis of a 3-D robotic fish model which has the typical geometry of body and tail with periodic flapping 2-freedom kinematical motion testing in the case of St = 0.78, Re = 6,600 and phase delay mode (φ = - 75°), in which may have a greater or maximum propulsion (without consideration of the optimal efficiency). Using a special technique of dye visualization which can clearly show vortex sheet and vortices in detail and using the inner 3-component force balance and cable supporting system with the phase-lock technique, the 3-D flow structure visualized in the wake of fish and the hydrodynamic force measurement were synchronized and obtained. Under the mentioned flapping parameters, we found the key flow structure and its evolution, a pair of complex 3-D chain-shape vortex (S-H vortex-rings, S1 - H1 and S2 - H2, and their legs L1 and L2) flow structures, which attach the leading edge and the trailing edge, then shed, move downstream and outwards and distribute two antisymmetric staggering arrays along with the wake of the fish model in different phase stages during the flapping period. It is different with in the case of St = 0.25-0.35. Its typical flow structure and evolution are described and the results prove that they are different from the viewpoints based on the investigation of 2-D cases. For precision of the dynamic force measurement, in this paper it was provided with the method and techniques by subtracting the inertial forces and the forces induced by buoyancy and gravity effect in water, etc. from original data measured. The evolution of the synchronized measuring forces directly matching with the flow structure was also described in this paper.

  7. Critical force during tethered swimming for the evaluation of aerobic capacity and prediction of performances in freestyle swimming DOI:10.5007/1980-0037.2010v12n1p14

    Directory of Open Access Journals (Sweden)

    Marcelo Papoti

    2010-12-01

    Full Text Available The present study investigated the relationship of critical force (Fcrit with lactate threshold (LLNA and the intensity corresponding to VO2max (iVO2max in tethered swimming (TS, and their correlation with maximal performance in 400-m (V400 and 30-min (VT30 freestyle swimming (FS. Seven swimmers were submitted to a TS incremental test for the determination of LLNA and iVO2max. For the determination of Fcrit, the swimmers performed four exercises to exhaustion at intensities (F corresponding to 87%, 104%, 118% and 134% of iVO2max for the calculation of time limits (Tlim. Fcrit corresponded to the linear coefficient of the ratio between F and 1/tlim. The maximal performance in FS corresponded to the mean velocity obtained during maximal exercise of 400-m and 30-min crawl swimming. Fcrit (51.97 ± 4.02 N was significantly lower than iVO2max (60.21 ± 8.73 N but not than LLNA (45.89 ± 8.73. Fcrit was significantly correlated with iVO2max (0.97, LLNA (0.88, V400 (0.85, and VT30 (0.86. These data suggest that Fcrit can be used for the determination of aerobic capacity, prescription of a TS training program, and prediction of performance in FS.

  8. Galanin (1-15) enhancement of the behavioral effects of Fluoxetine in the forced swimming test gives a new therapeutic strategy against depression.

    Science.gov (United States)

    Flores-Burgess, Antonio; Millón, Carmelo; Gago, Belén; Narváez, Manuel; Borroto-Escuela, Dasiel O; Mengod, Guadalupe; Narváez, José Angel; Fuxe, Kjell; Santín, Luis; Díaz-Cabiale, Zaida

    2017-05-15

    The pharmacological treatment of major depression is mainly based on drugs elevating serotonergic (5-HT) activity. Specifically, selective 5-HT reuptake inhibitors, including Fluoxetine (FLX), are the most commonly used for treatment of major depression. However, the understanding of the mechanism of action of FLX beyond its effect of elevating 5-HT is limited. The interaction between serotoninergic system and neuropeptides signaling could be a key aspect. We examined the ability of the neuropeptide Galanin(1-15) [GAL(1-15)] to modulate the behavioral effects of FLX in the forced swimming test (FST) and studied feasible molecular mechanisms. The data show that GAL(1-15) enhances the antidepressant-like effects induced by FLX in the FST, and we demonstrate the involvement of GALR1/GALR2 heteroreceptor complex in the GAL(1-15)-mediated effect using in vivo rat models for siRNA GALR1 or GALR2 knockdown. Importantly, 5-HT1A receptors (5HT1A-R) also participate in the GAL(1-15)/FLX interactions since the 5HT1AR antagonist WAY100635 blocked the behavioral effects in the FST induced by the coadministration of GAL(1-15) and FLX. The mechanism underlying GAL(1-15)/FLX interactions affected the binding characteristics as well as the mRNA levels of 5-HT1A-R specifically in the dorsal hippocampus while leaving unaffected mRNA levels and affinity and binding sites of this receptor in the dorsal raphe. The results open up the possibility to use GAL(1-15) as for a combination therapy with FLX as a novel strategy for treatment of depression. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Repeated forced swim stress enhances CFA-evoked thermal hyperalgesia and affects the expressions of pCREB and c-Fos in the insular cortex.

    Science.gov (United States)

    Imbe, H; Kimura, A; Donishi, T; Kaneoke, Y

    2014-02-14

    Stress affects brain activity and promotes long-term changes in multiple neural systems. Exposure to stressors causes substantial effects on the perception and response to pain. In several animal models, chronic stress produces lasting hyperalgesia. The insular (IC) and anterior cingulate cortices (ACC) are the regions exhibiting most reliable pain-related activity. And the IC and ACC play an important role in pain modulation via the descending pain modulatory system. In the present study we examined the expression of phospho-cAMP response element-binding protein (pCREB) and c-Fos in the IC and ACC after forced swim stress (FS) and complete Freund's adjuvant (CFA) injection to clarify changes in the cerebral cortices that affect the activity of the descending pain modulatory system in the rats with stress-induced hyperalgesia. FS (day 1, 10min; days 2-3, 20min) induced an increase in the expression of pCREB and c-Fos in the anterior IC (AIC). CFA injection into the hindpaw after the FS shows significantly enhanced thermal hyperalgesia and induced a decrease in the expression of c-Fos in the AIC and the posterior IC (PIC). Quantitative image analysis showed that the numbers of c-Fos-immunoreactive neurons in the left AIC and PIC were significantly lower in the FS+CFA group (L AIC, 95.9±6.8; L PIC, 181.9±23.1) than those in the naive group (L AIC, 151.1±19.3, pCFA-induced thermal hyperalgesia through dysfunction of the descending pain modulatory system. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Maternal swimming exercise during pregnancy attenuates anxiety/depressive-like behaviors and voluntary morphine consumption in the pubertal male and female rat offspring born from morphine dependent mothers.

    Science.gov (United States)

    Torabi, Masoumeh; Pooriamehr, Alireza; Bigdeli, Imanollah; Miladi-Gorji, Hossein

    2017-10-17

    This study was designed to examine whether maternal swimming exercise during pregnancy would attenuate prenatally morphine-induced anxiety, depression and voluntary consumption of morphine in the pubertal male and female rat offspring. Pregnant rats during the development of morphine dependence were allowed to swim (30-45min/d, 3days per a week) on gestational days 11-18. Then, the pubertal male and female rat offspring were tested for the elevated plus-maze (EPM), sucrose preference test (SPT) and voluntary morphine consumption using a two-bottle choice (TBC) paradigm. The results showed that male and female rat offspring born of the swimmer morphine-dependent mothers exhibited an increase in EPM open arm time and entries, higher levels of sucrose preference than their sedentary control mothers. Voluntary consumption of morphine was less in the male and female rat offspring born of the swimmer morphine-dependent mothers as compared with their sedentary control mothers during three periods of the intake of drug. Thus, swimming exercise in pregnant morphine dependent mothers decreased anxiety, depressive-like behavior and also the voluntary morphine consumption in the pubertal male and female offspring, which may prevent prenatally morphine-induced behavioral sensitization in offspring. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Sex-Specific Diurnal Immobility Induced by Forced Swim Test in Wild Type and Clock Gene Deficient Mice

    Directory of Open Access Journals (Sweden)

    Ningyue Li

    2015-03-01

    Full Text Available Objective: The link between alterations in circadian rhythms and depression are well established, but the underlying mechanisms are far less elucidated. We investigated the circadian characteristics of immobility behavior in wild type (WT mice and mice with mutations in core Clock genes. Methods: All mice were tested with forced swim test (FST at 4 h intervals. Results: These experiments revealed significant diurnal rhythms associated with immobility behavior in both male and female WT mice with sex-different circadian properties. In addition, male mice showed significantly less immobility during the night phase in comparison to female mice. Female Per1Brdm1 mice also showed significant rhythmicity. However, the timing of rhythmicity was very different from that observed in female wild type mice. Male Per1Brdm1 mice showed a pattern of rhythmicity similar to that of wild type mice. Furthermore, female Per1Brdm1 mice showed higher duration of immobility in comparison to male Per1Brdm1 mice in both daytime and early night phases. Neither Per2Brdm1 nor ClockΔ19 mice showed significant rhythmicity, but both female Per2Brdm1 and ClockΔ19 mice had lower levels of immobility, compared to males. Conclusions: This study highlights the differences in the circadian characteristics of immobility induced by FST in WT, ClockΔ19, Per1, and Per2 deficient mice.

  12. The effects of ifenprodil on the activity of antidepressant drugs in the forced swim test in mice.

    Science.gov (United States)

    Poleszak, Ewa; Wośko, Sylwia; Serefko, Anna; Wlaź, Aleksandra; Kasperek, Regina; Dudka, Jarosław; Wróbel, Andrzej; Nowak, Gabriel; Wlaź, Piotr

    2014-12-01

    According to reports in the literature, more than 30% of depressive patients fail to achieve remission. Therapy with the conventional antidepressant drugs may induce the serious adverse reactions. Moreover, its benefits may be seen at least 2-4 weeks after the first dose. Therefore, the alternative strategies for prevention and treatment of depression are sought. The main aim of our study was to assess the effects of ifenprodil given at a non-active dose (10mg/kg) on the activity of antidepressant agents from diverse pharmacological groups. The antidepressant-like effect was assessed by the forced swim test in mice. Ifenprodil potentiated the antidepressant-like effect of imipramine (15mg/kg) and fluoxetine (5mg/kg) while did not reduce the immobility time of animals which simultaneously received reboxetine (2.5mg/kg) or tianeptine (15mg/kg). The concomitant administration of certain commonly prescribed antidepressant drugs that affect the serotonergic neurotransmission (i.e., typical tricyclic antidepressants and selective serotonin reuptake inhibitors) with a negative modulator selectively binding to the GluN1/N2B subunits of the NMDA receptor complex (i.e., ifenprodil) may induce a more pronounced antidepressant-like effect than monotherapy. However, these findings still need to be confirmed in further experiments. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  13. Involvement of NMDA receptors in the antidepressant-like effect of tramadol in the mouse forced swimming test.

    Science.gov (United States)

    Ostadhadi, Sattar; Norouzi-Javidan, Abbas; Chamanara, Mohsen; Akbarian, Reyhaneh; Imran-Khan, Muhammad; Ghasemi, Mehdi; Dehpour, Ahmad-Reza

    2017-09-01

    Tramadol is an analgesic agent that is mainly used to treat moderate to severe pain. There is evidence that tramadol may have antidepressant property. However, the mechanisms underlying the antidepressant effects of tramadol have not been elucidated yet. Considering that fact that N-methyl-d-aspartate (NMDA) receptor signaling may play an important role in the pathophysiology of depression, the aim of the present study was to investigate the role of NMDA receptor signaling in the possible antidepressant-like effects of tramadol in the mouse forced swimming test (mFST). We found that tramadol exerted antidepressant-like effects at high dose (40mg/kg, intraperitoneally [i.p.]) in the mFST. Co-administration of non-effective doses of NMDA receptor antagonists (ketamine [1mg/kg, i.p.], MK-801 [0.05mg/kg, i.p.], or magnesium sulfate [10mg/kg, i.p.]) with sub-effective dose of tramadol (20mg/kg, i.p.) exerted significant antidepressant-like effects in the mFST. The antidepressant-like effects of tramadol (40mg/kg) was also inhibited by pre-treatment with non-effective dose of the NMDA receptor agonist NMDA (75mg/kg, i.p.). Our data suggest a role for NMDA receptor signaling in the antidepressant-like effects of tramadol in the mFST. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Involvement of NO/cGMP pathway in the antidepressant-like effect of gabapentin in mouse forced swimming test.

    Science.gov (United States)

    Ostadhadi, Sattar; Kordjazy, Nastaran; Haj-Mirzaian, Arya; Ameli, Sanaz; Akhlaghipour, Golnoosh; Dehpour, AhmadReza

    2016-04-01

    Based on clinical studies regarding the beneficial effect of gabapentin in depression, we aimed to evaluate the antidepressant-like properties of gabapentin in mice and also the participation of nitric oxide (NO)/cyclic guanosine monophosphate pathway in this effect. The following drugs were used in this study: gabapentin; N(G)-nitro-L-arginine methyl ester (L-NAME), a non-specific NO synthase (NOS) inhibitor; 7-nitroindazole, a specific neuronal NOS inhibitor; aminoguanidine, a specific inducible NOS inhibitor; L-arginine, a NO precursor; and sildenafil, a phosphodiestrase inhibitor. Finally, we studied the behavioral effects through the forced swimming test (FST) and the changes of the hippocampus NO level through nitrite assay. The immobility time was significantly reduced after gabapentin administration. Co-administration of non-effective doses of gabapentin and L-NAME or 7-nitroindazole (7-NI) resulted in antidepressant-like effect in FST, while aminoguanidine did not affect the immobility time of gabapentin-treated mice. Furthermore, the antidepressant-like property of gabapentin was prevented by L-arginine or sildenafil. Also, the hippocampal nitrite level was significantly lower in gabapentin-treated mice relative to saline-injected mice, and co-administration of 7-NI with sub-effective gabapentin caused a significant decrease in hippocampal nitrite levels. Our results indicate that the antidepressant-like effect of gabapentin in the mice FST model is mediated at least in part through nitric oxide/cyclic guanosine monophosphate (cGMP) pathway.

  15. Desipramine restricts estral cycle oscillations in swimming.

    Science.gov (United States)

    Contreras, C M; Martínez-Mota, L; Saavedra, M

    1998-10-01

    1. Desipramine (DMI) is a tricyclic antidepressant which reduces the immobility in rats forced to swim; however, it is unknown whether estral cycle phases impinge on DMI actions on immobility in daily swimming tests during several weeks. 2. In female wistar rats, vaginal smears taken before testing defined four estral phases. Afterwards, the authors assessed the latency for the first period of immobility in five-min forced swim tests practiced on 21-day DMI (DMI group), 21-day washout saline given after a 21-day DMI treatment (washout-saline group), or non-treated rats (control group). 3. We observed a longer latency for the first period of immobility in proestrus-estrus from the control and washout-saline groups. The 21-day treatment with DMI (2.1 mg/kg i.p., once a day) significantly (p estral cycle phase. 4. It is concluded that proestrus-estrus relates to increased struggling behavior. DMI enhances struggling behavior independently of hormonal state.

  16. Chronic oral nicotine increases brain [3H]epibatidine binding and responsiveness to antidepressant drugs, but not nicotine, in the mouse forced swim test

    DEFF Research Database (Denmark)

    Andreasen T., Jesper; Nielsen, Elsebet O; Redrobe, John P

    2009-01-01

    Smoking rates among depressed individuals is higher than among healthy subjects, and nicotine alleviates depressive symptoms. Nicotine increases serotonergic and noradrenergic neuronal activity and facilitates serotonin and noradrenaline release. In mice, acute nicotine administration enhances...... the activity of antidepressants in the mouse forced swim (mFST) and tail suspension tests. Here, we investigated if this action of nicotine is also reflected in a chronic treatment regimen....

  17. Effects of MK-886, a 5-lipoxygenase activating protein (FLAP) inhibitor, and 5-lipoxygenase deficiency on the forced swimming behavior of mice

    Science.gov (United States)

    Uz, Tolga; Dimitrijevic, Nikola; Imbesi, Marta; Manev, Hari; Manev, Radmila

    2008-01-01

    A common biological pathway may contribute to the comorbidity of atherosclerosis and depression. Increased activity of the enzymatic 5-lipoxygenase (5-LOX; 5LO) pathway is a contributing factor in atherosclerosis and a 5-LOX inhibitor, MK-886, is beneficial in animal models of atherosclerosis. In the brain, MK-886 increases phosphorylation of the glutamate receptor subunit GluR1, and the increased phosphorylation of this receptor has been associated with antidepressant treatment. In this work, we evaluated the behavioral effects of MK-886 in an automated assay of mouse forced swimming, which identifies antidepressant activity as increased climbing behavior and/or decreased rest time. Whereas a single injection of MK-886 (3 and 10 mg/kg) did not affect forced swimming behaviors assayed 30 min later, 6 daily injections of 3 mg/kg MK-886 slightly increased climbing and significantly reduced rest time in wild-type mice but not in 5-LOX-deficient mice. A diet delivery of MK-886, 4 μg per 100 mg body-weight per day, required three weeks to affect forced swimming; it increased climbing behavior. Climbing behavior was also increased in naive 5-LOX-deficient mice compared to naive wild-type controls. These results suggest that 5-LOX inhibition and deficiency may be associated with antidepressant activity. Increased climbing in a forced swimming assay is a typical outcome of antidepressants that increase noradrenergic and dopaminergic activity. Interestingly, 5-LOX deficiency and MK-886 treatment have been shown to be capable of increasing the behavioral effects of a noradrenaline/dopamine-potentiating drug, cocaine. Future research is needed to evaluate the clinical relevance of our findings. PMID:18403121

  18. Is Forced Swimming Immobility a Good Endpoint for Modeling Negative Symptoms of Schizophrenia? - Study of Sub-Anesthetic Ketamine Repeated Administration Effects

    Directory of Open Access Journals (Sweden)

    GILDA NEVES

    2017-08-01

    Full Text Available ABSTRACT Immobility time in the forced swimming has been described as analogous to emotional blunting or apathy and has been used for characterizing schizophrenia animal models. Several clinical studies support the use of NMDA receptor antagonists to model schizophrenia in rodents. Some works describe the effects of ketamine on immobility behavior but there is variability in the experimental design used leading to controversial results. In this study, we evaluated the effects of repeated administration of ketamine sub-anesthetic doses in forced swimming, locomotion in response to novelty and novel object recognition, aiming a broader evaluation of the usefulness of this experimental approach for modeling schizophrenia in mice. Ketamine (30 mg/kg/day i.p. for 14 days induced a not persistent decrease in immobility time, detected 24h but not 72h after treatment. This same administration protocol induced a deficit in novel object recognition. No change was observed in mice locomotion. Our results confirm that repeated administration of sub-anesthetic doses of ketamine is useful in modeling schizophrenia-related behavioral changes in mice. However, the immobility time during forced swimming does not seem to be a good endpoint to evaluate the modeling of negative symptoms in NMDAR antagonist animal models of schizophrenia.

  19. Effects of co-treatment with mirtazapine and low doses of risperidone on immobility time in the forced swimming test in mice.

    Science.gov (United States)

    Rogóż, Zofia

    2010-01-01

    The aim of the present study was to examine the effect of mirtazapine (MIR) and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. Fluoxetine (FLU) was used as a reference drug. MIR (2.5, 5 and 10 mg/kg) and FLU (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Joint administration of MIR (5 and 10 mg/kg) or FLU (10 mg/kg) and risperidone (0.1 mg/kg) produced antidepressant-like activity in the forced swimming test. WAY100636 (a 5-HT(1A) receptor antagonist) inhibited, while yohimbine (an α(2)-adrenergic receptor antagonist) potentiated the antidepressant-like effect induced by co-administration of MIR and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined administration of antidepressants and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of MIR and that, among other mechanisms, 5-HT(1A)-, and α(2)-adrenergic receptors may play a role in this effect.

  20. Forced swimming sabotages the morphological and synaptic maturation of newborn granule neurons and triggers a unique pro-inflammatory milieu in the hippocampus.

    Science.gov (United States)

    Llorens-Martín, María; Jurado-Arjona, Jerónimo; Bolós, Marta; Pallas-Bazarra, Noemí; Ávila, Jesús

    2016-03-01

    Recent experimental data suggest that mood disorders are related to inflammatory phenomena and have led to the "inflammatory hypothesis of depression". Given that the hippocampus is one of the most affected areas in these disorders, we used a model of acute stress (the Porsolt test) to evaluate the consequences of forced swimming on two crucial events related to the pathophysiology of major depression: the functional maturation of newborn granule neurons; and the hippocampal inflammatory milieu. Using PSD95:GFP-expressing retroviruses, we found that forced swimming selectively alters the dendritic morphology of newborn neurons and impairs their connectivity by reducing the number and volume of their postsynaptic densities. In addition, acute stress triggered a series of morphological changes in microglial cells, together with an increase in microglial CD68 expression, thus suggesting the functional and morphological activation of this cell population. Furthermore, we observed an intriguing change in the hippocampal inflammatory milieu in response to forced swimming. Importantly, the levels of several molecules affected by acute stress (such as Interleukin-6 and eotaxin) have been described to also be altered in patients with depression and other mood disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Is Forced Swimming Immobility a Good Endpoint for Modeling Negative Symptoms of Schizophrenia? - Study of Sub-Anesthetic Ketamine Repeated Administration Effects.

    Science.gov (United States)

    Neves, Gilda; Borsoi, Milene; Antonio, Camila B; Pranke, Mariana A; Betti, Andresa H; Rates, Stela M K

    2017-01-01

    Immobility time in the forced swimming has been described as analogous to emotional blunting or apathy and has been used for characterizing schizophrenia animal models. Several clinical studies support the use of NMDA receptor antagonists to model schizophrenia in rodents. Some works describe the effects of ketamine on immobility behavior but there is variability in the experimental design used leading to controversial results. In this study, we evaluated the effects of repeated administration of ketamine sub-anesthetic doses in forced swimming, locomotion in response to novelty and novel object recognition, aiming a broader evaluation of the usefulness of this experimental approach for modeling schizophrenia in mice. Ketamine (30 mg/kg/day i.p. for 14 days) induced a not persistent decrease in immobility time, detected 24h but not 72h after treatment. This same administration protocol induced a deficit in novel object recognition. No change was observed in mice locomotion. Our results confirm that repeated administration of sub-anesthetic doses of ketamine is useful in modeling schizophrenia-related behavioral changes in mice. However, the immobility time during forced swimming does not seem to be a good endpoint to evaluate the modeling of negative symptoms in NMDAR antagonist animal models of schizophrenia.

  2. Effects of Eleutherococcus senticosus Cortex on Recovery from the Forced Swimming Test and Fatty Acid β-Oxidation in the Liver and Skeletal Muscle of mice.

    Science.gov (United States)

    Sumiyoshi, Maho; Kimura, Yoshiyuki

    2016-03-01

    The root and stem barks of Eleutherococcus senticosus have been used to treat emotional and physical fatigue in China, Russia, Korea, and Japan. The effects of E. senticosus on recovery from physical fatigue and the expenditure of energy currently remain unclear. We herein examined the effects of E. senticosus extract on recovery from physical fatigue after the forced swimming test as well as fatty acid β-oxidation in the liver and skeletal muscle of mice. 1) Physical fatigue; E. senticosus extract (500 and 1000 mg/kg, twice daily) was administered orally to ICR male mice for 7 consecutive days. After swimming had been performed for 15 min, each mouse was placed on the cover of a 100-mm culture plate, and the time for each mouse to move away from the cover was measured. 2) Fatty acid β-oxidation in the liver and skeletal muscle; E. senticosus extract (500 and 1000 mg/kg) was administered orally twice daily to C57BL/6J male mice for 21 consecutive days. The initial and final body and liver weight were measured, and then fatty acid β-oxidation activity in the liver and skeletal muscle was measured by methods using [1- 14 C] palmitic acid. Recovery times after forced swimming were shorter in E. senticosus extract (500 and 1000 mg/kg)-treated mice than in vehicle-treated mice. The body and liver weight had no effect by the oral administration of E. senticosus extract, vitamin mixture and L-carnitine. Fatty acid β-oxidation activity in skeletal muscle was increased by E. senticosus extract (500 and 1000 mg/kg). E. senticosus may enhance recovery from physical fatigue induced by forced swimming by accelerating energy changes through fatty acid β-oxidation in skeletal muscle.

  3. Alterations in Plasma Glucose and Cardiac Antioxidant Enzymes Activity in Streptozotocin-Induced Diabetic Rats: Effects of Trigonella foenum-graecum Extract and Swimming Training.

    Science.gov (United States)

    Haghani, Karimeh; Bakhtiyari, Salar; Doost Mohammadpour, Jafar

    2016-04-01

    Diabetes mellitus is a group of metabolic diseases characterized by chronic hyperglycemia. Trigonella foenum-graecum (fenugreek) and swimming training have previously been reported to have hypoglycemic and antioxidant effects. We aimed to evaluate the effects of swimming training and fenugreek aqueous extract, alone and in combination, on plasma glucose and cardiac antioxidant enzymes activity of streptozotocin-induced diabetes in rats. We divided 70 male Wistar rats equally into 7 groups: diabetic control (DC), healthy control (HC), swimming (S), fenugreek seed extract (1.74 g/kg) (F1), fenugreek seed extract (0.87 g/kg) (F2), swimming + fenugreek seed extract (1.74 g/kg) (SF1), and swimming + fenugreek seed extract (0.87 g/kg) (SF2). We used streptozotocin for the induction of diabetes. Statistical analyses were performed using the statistical program SPSS. We did not detect any significant differences in body weight in the F1, F2, S, SF1 and SF2 groups compared with the DC group (p>0.05). The results also revealed that the hypoglycemic effect of combined swimming and fenugreek was significantly stronger (pswimming could be useful for the treatment of hyperglycemia and cardiac oxidative stress induced by type 1 diabetes mellitus. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  4. Estradiol or fluoxetine alters depressive behavior and tryptophan hydroxylase in rat raphe.

    Science.gov (United States)

    Yang, Fu-Zhong; Wu, Yan; Zhang, Wei-Guo; Cai, Yi-Yun; Shi, Shen-Xun

    2010-03-10

    The effects of 17beta-estradiol and fluoxetine on behavior of ovariectomized rats subjected to the forced swimming test and the expression of tryptophan hydroxylase (TPH) in dorsal and median raphe were investigated, respectively through time sampling technique of behavior scoring and immunohistochemistry. Both estradiol and fluoxetine increased swimming and decreased immobility in the forced swimming test. The forced swimming stress decreased integrated optical density of TPH-positive regions in dorsal and median raphe. Both estradiol and fluoxetine administration prevented integrated optical density of TPH-positive regions from being decreased by forced swimming stress. These observations suggest that both estradiol and fluoxetine have protective bearing on ovariectomized rats enduring forced swimming stress.

  5. The effect of GABAmimetics on the duration of immobility in the forced swim test in albino mice.

    Science.gov (United States)

    El Zahaf, Najwa Ahmed; Salem Elhwuegi, Abdalla

    2014-01-01

    Studies regarding the role of gamma aminobutyric acid (GABA) in depression are conflicting. Therefore, it was decided to examine the effect of different drugs that enhance the GABA system on the time of immobility induced by the forced swim test (FST). Adult albino mice were divided into several groups of six animals. Each group received an intraperitoneal injection of either imipramine (10, 20, or 30 mg/kg), diazepam (0.5, 1, or 2 mg/kg), vigabatrin (100, 200, or 300 mg/kg), zolpidem (2.5, 5, or 10 mg/kg), or alprazolam (1, 2.5, or 5 mg/kg). Control groups received the appropriate vehicle. One hour after injection, the duration of immobility was measured for 5 min in the FST. The percentage change in the duration of immobility from the control was calculated for each group. The statistical test of the difference between the treated and the control groups was calculated using unpaired Student's t-test. Imipramine produced a significant dose-dependent decrease in the duration of immobility (78, 74, and 56%, respectively). Different doses of diazepam, vigabatrin, and zolpidem produced a significant increase in the duration of immobility (119, 126, and 128%), (116, 124, and 128%), and (108, 109, and 119%), respectively. The two low doses of alprazolam produced a significant increase (115 and 120%), while the high dose produced a significant decrease in the duration of immobility (74%). Increasing central GABAergic activity by different mechanisms has resulted in a depressant-like activity measured as an increase in the duration of immobility in the FST model of depression.

  6. Guanosine prevents behavioral alterations in the forced swimming test and hippocampal oxidative damage induced by acute restraint stress.

    Science.gov (United States)

    Bettio, Luis E B; Freitas, Andiara E; Neis, Vivian B; Santos, Danúbia B; Ribeiro, Camille M; Rosa, Priscila B; Farina, Marcelo; Rodrigues, Ana Lúcia S

    2014-12-01

    Guanosine is a guanine-based purine that modulates glutamate uptake and exerts neurotrophic and neuroprotective effects. In a previous study, our group demonstrated that this endogenous nucleoside displays antidepressant-like properties in a predictive animal model. Based on the role of oxidative stress in modulating depressive disorders as well as on the association between the neuroprotective and antioxidant properties of guanosine, here we investigated if its antidepressant-like effect is accompanied by a modulation of hippocampal oxidant/antioxidant parameters. Adult Swiss mice were submitted to an acute restraint stress protocol, which is known to cause behavioral changes that are associated with neuronal oxidative damage. Animals submitted to ARS exhibited an increased immobility time in the forced swimming test (FST) and the administration of guanosine (5mg/kg, p.o.) or fluoxetine (10mg/kg, p.o., positive control) before the exposure to stressor prevented this alteration. Moreover, the significantly increased levels of hippocampal malondialdehyde (MDA; an indicator of lipid peroxidation), induced by ARS were not observed in stressed mice treated with guanosine. Although no changes were found in the hippocampal levels of reduced glutathione (GSH), the group submitted to ARS procedure presented enhanced glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) activities and reduced catalase (CAT) activity in the hippocampus. Guanosine was able to prevent the alterations in GPx, GR, CAT activities, and in SOD/CAT activity ratio, but potentiated the increase in SOD activity elicited by ARS. Altogether, the present findings indicate that the observed antidepressant-like effects of guanosine might be related, at least in part, to its capability of modulating antioxidant defenses and mitigating hippocampal oxidative damage induced by ARS. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Chronic exercise prevents repeated restraint stress-provoked enhancement of immobility in forced swimming test in ovariectomized mice.

    Science.gov (United States)

    Han, Tae-Kyung; Lee, Jang-Kyu; Leem, Yea-Hyun

    2015-06-01

    We assessed whether chronic treadmill exercise attenuated the depressive phenotype induced by restraint stress in ovariectomized mice (OVX). Immobility of OVX in the forced swimming test was comparable to that of sham mice (CON) regardless of the postoperative time. Immobility was also no difference between restrained mice (exposure to periodic restraint for 21 days; RST) and control mice (CON) on post-exposure 2nd and 9th day, but not 15th day. In contrast, the immobility of ovariectomized mice with repeated stress (OVX + RST) was profoundly enhanced compared to ovariectomized mice-alone (OVX), and this effect was reversed by chronic exercise (19 m/min, 60 min/day, 5 days/week for 8 weeks; OVX + RST + Ex) or fluoxetine administration (20 mg/kg, OVX + RST + Flu). In parallel with behavioral data, the immunoreactivity of Ki-67 and doublecortin (DCX) in OVX was significantly decreased by repeated stress. However, the reduced numbers of Ki-67- and DCX-positive cells in OVX + RST were restored in response to chronic exercise (OVX + RST + Ex) and fluoxetine (OVX + RST + Flu). In addition, the expression pattern of cAMP response element-binding protein (CREB) and calcium-calmodulin-dependent kinase IV (CaMKIV) was similar to that of the hippocampal proliferation and neurogenesis markers (Ki-67 and DCX, respectively). These results suggest that menopausal depression may be induced by an interaction between repeated stress and low hormone levels, rather than a deficit in ovarian secretion alone, which can be improved by chronic exercise.

  8. Agmatine enhances the antidepressant-like effect of lithium in mouse forced swimming test through NMDA pathway.

    Science.gov (United States)

    Mohseni, Gholmreza; Ostadhadi, Sattar; Imran-Khan, Muhammad; Norouzi-Javidan, Abbas; Zolfaghari, Samira; Haddadi, Nazgol-Sadat; Dehpour, Ahmad-Reza

    2017-04-01

    Depression is one the world leading global burdens leading to various comorbidities. Lithium as a mainstay in the treatment of depression is still considered gold standard treatment. Similar to lithium another agent agmatine has also central protective role against depression. Since, both agmatine and lithium modulate various effects through interaction with NMDA receptor, therefore, in current study we aimed to investigate the synergistic antidepressant-like effect of agmatine with lithium in mouse force swimming test. Also to know whether if such effect is due to interaction with NMDA receptor. In our present study we found that when potent dose of lithium (30mg/kg) was administered, it significantly decreased the immobility time. Also, when subeffective dose of agmatine (0.01mg/kg) was coadministered with subeffective dose of lithium (3mg/kg), it potentiated the antidepressant-like effect of subeffective dose of lithium. For the involvement of NMDA receptor in such effect, we administered NMDA receptor antagonist MK-801 (0.05mg/kg) with a combination of subeffective dose of lithium (3mg/kg) and agmatine (0.001mg/kg). A significant antidepressant-like effect was observed. Furthermore, when subeffective dose (50 and 75mg/kg) of NMDA was given it inhibited the synergistic effect of agmatine (0.01mg/kg) with lithium (3mg/kg). Hence, our finding demonstrate that agmatine have synergistic effect with lithium which is mediated by NMDA receptor pathway. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. Strain differences in paroxetine-induced reduction of immobility time in the forced swimming test in mice: role of serotonin.

    Science.gov (United States)

    Guzzetti, Sara; Calcagno, Eleonora; Canetta, Alessandro; Sacchetti, Giuseppina; Fracasso, Claudia; Caccia, Silvio; Cervo, Luigi; Invernizzi, Roberto W

    2008-10-10

    We studied the antidepressant-like effect of paroxetine in strains of mice carrying different isoforms of tryptophan hydroxylase-2 (TPH-2), the enzyme responsible for the synthesis of brain serotonin (5-HT). The effect of paroxetine alone and in combination with pharmacological treatments enhancing or lowering 5-HT synthesis or melatonin was assessed in the forced swimming test in mice carrying allelic variants of TPH-2 (1473C in C57BL/6 and 1473G in DBA/2 and BALB/c). Changes in brain 5-hydroxytryptophan (5-HTP) accumulation and melatonin levels were measured by high-performance liquid chromatography. Paroxetine (2.5 and 5 mg/kg) reduced immobility time in C57BL/6J and C57BL/6N mice but had no such effect in DBA/2J, DBA/2N and BALB/c mice, even at 10 mg/kg. Enhancing 5-HT synthesis with tryptophan reinstated the antidepressant-like effect of paroxetine in DBA/2J, DBA/2N and BALB/c mice whereas inhibition of 5-HT synthesis prevented the effect of paroxetine in C57BL/6N mice. The response to paroxetine was not associated with changes in locomotor activity, brain melatonin or brain levels of the drug measured at the end of the behavioral test. These results support the importance of 5-HT synthesis in the response to SSRIs and suggest that melatonin does not contribute to the ability of tryptophan to rescue the antidepressant-like effect of paroxetine.

  10. A diphenyl diselenide-supplemented diet and swimming exercise promote neuroprotection, reduced cell apoptosis and glial cell activation in the hypothalamus of old rats.

    Science.gov (United States)

    Leite, Marlon R; Cechella, José L; Pinton, Simone; Nogueira, Cristina W; Zeni, Gilson

    2016-09-01

    Aging is a process characterized by deterioration of the homeostasis of various physiological systems; although being a process under influence of multiple factors, the mechanisms involved in aging are not well understood. Here we investigated the effect of a (PhSe)2-supplemented diet (1ppm, 4weeks) and swimming exercise (1% of body weight, 20min per day, 4weeks) on proteins related to glial cells activation, apoptosis and neuroprotection in the hypothalamus of old male Wistar rats (27month-old). Old rats had activation of astrocytes and microglia which was demonstrated by the increase in the levels of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (Iba-1) in hypothalamus. A decrease of B-cell lymphoma 2 (Bcl-2) and procaspase-3 levels as well as an increase of the cleaved PARP/full length PARP ratio (poly (ADP-ribose) polymerase, PARP) and the pJNK/JNK ratio (c-Jun N-terminal kinase, JNK) were observed. The levels of mature brain-derived neurotrophic factor (mBDNF), the pAkt/Akt ratio (also known as protein kinase B) and NeuN (neuronal nuclei), a neuron marker, were decreased in the hypothalamus of old rats. Old rats that received a (PhSe)2-supplemented diet and performed swimming exercise had the hypothalamic levels of Iba-1 and GFAP decreased. The combined treatment also increased the levels of Bcl-2 and procaspase-3 and decreased the ratios of cleaved PARP/full length PARP and pJNK/JNK in old rats. The levels of mBDNF and NeuN, but not the pAkt/Akt ratio, were increased by combined treatment. In conclusion, a (PhSe)2-supplemented diet and swimming exercise promoted neuroprotection in the hypothalamus of old rats, reducing apoptosis and glial cell activation. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Proteomic and carbonylation profile analysis of rat skeletal muscles following acute swimming exercise.

    Directory of Open Access Journals (Sweden)

    Francesca Magherini

    Full Text Available Previous studies by us and other groups characterized protein expression variation following long-term moderate training, whereas the effects of single bursts of exercise are less known. Making use of a proteomic approach, we investigated the effects of acute swimming exercise (ASE on protein expression and carbonylation patterns in two hind limb muscles: the Extensor Digitorum Longus (EDL and the Soleus, mostly composed of fast-twitch and slow-twitch fibres, respectively. Carbonylation is one of the most common oxidative modifications of proteins and a marker of oxidative stress. In fact, several studies suggest that physical activity and the consequent increase in oxygen consumption can lead to increase in reactive oxygen and nitrogen species (RONS production, hence the interest in examining the impact of RONS on skeletal muscle proteins following ASE. Results indicate that protein expression is unaffected by ASE in both muscle types. Unexpectedly, the protein carbonylation level was reduced following ASE. In particular, the analysis found 31 and 5 spots, in Soleus and EDL muscles respectively, whose carbonylation is reduced after ASE. Lipid peroxidation levels in Soleus were markedly reduced as well. Most of the decarbonylated proteins are involved either in the regulation of muscle contractions or in the regulation of energy metabolism. A number of hypotheses may be advanced to account for such results, which will be addressed in future studies.

  12. Suckling in litters with different sizes, and early and late swimming exercise differentially modulates anxiety-like behavior, memory and electrocorticogram potentiation after spreading depression in rats.

    Science.gov (United States)

    E Silva-Gondim, Mariana Barros; de Souza, Thays Kallyne Marinho; Rodrigues, Marcelo Cairrão Araújo; Guedes, Rubem Carlos Araújo

    2017-11-28

    Analyze the hypothesis that swimming exercise, in rats suckled under distinct litter sizes, alters behavioral parameters suggestive of anxiety and recognition memory, and the electrocorticogram potentiation that occurs after the excitability-related phenomenon that is known as cortical spreading depression (CSD). Male Wistar rats were suckled in litters with six or 12 pups (L 6 and L 12 groups). Animals swam at postnatal days (P) 8-23, or P60-P75 (early-exercised or late-exercised groups, respectively), or remained no-exercised. Behavioral tests (open field - OF and object recognition - OR) were conducted between P77 and P80. Between P90 and P120, ECoG was recorded for 2 hours. After this 'baseline' recording, CSD was elicited every 30 minutes over the course of 2 hours. Early swimming enhanced the number of entries and the percentage of time in the OF-center (P < 0.05). In animals that swam later, this effect occurred in the L6 group only. Compared to the corresponding sedentary groups, OR-test showed a better memory in the L6 early exercised rats, and a worse memory in all other groups (P < 0.05). In comparison to baseline values, ECoG amplitudes after CSD increased 14-43% for all groups (P < 0.05). In the L 6 condition, early swimming and late swimming, respectively, reduced and enhanced the magnitude of the post-CSD ECoG potentiation in comparison with the corresponding L 6 no-exercised groups (P < 0.05). Our data suggest a differential effect of early- and late-exercise on the behavioral and electrophysiological parameters, suggesting an interaction between the age of exercise and the nutritional status during lactation.

  13. Effects of aspirin on immobile behavior and endocrine and immune changes in the forced swimming test: comparison to fluoxetine and imipramine.

    Science.gov (United States)

    Guan, Xi-ting; Shao, Feng; Xie, Xi; Chen, Lin; Wang, Weiwen

    2014-09-01

    Aspirin (ASP) is the most commonly used non-steroidal anti-inflammatory drug in the world. Recent clinical and preclinical evidence suggests that ASP may also exert psychoactive effects. It remains unclear whether ASP has antidepressant-like activity, and any molecular mechanisms underlying such activity have yet to be elucidated. Using the forced swimming test (FST), a well-established animal model of depression widely used to screen potential antidepressants in rodents, we investigated the effects of subacute treatment with ASP (0, 6, 12, 25, and 50mg/kg, i.p.) on immobility in the FST, and on FST-induced changes in endocrine and immune parameters in rats, in comparison to the clinical antidepressants imipramine (IMI) and fluoxetine (FLU). Serum levels of corticosterone, pro-inflammatory cytokine interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were determined by enzyme-linked immunosorbent assay. ASP dose-dependently decreased immobility in the FST, without altering the locomotor activity in the open-field test. The inhibitory effects of higher doses (25 and 50mg/kg) of ASP on immobility were similar to that of FLU and IMI at a dose of 10mg/kg. In addition, the levels of corticosterone, IL-6, and TNF-α in peripheral blood were significantly increased after the FST exposure. IMI, but not FLU and ASP at any dose tested, significantly attenuated corticosterone responses in the FST. Both FLU and IMI treatment reduced the increase of IL-6 and TNF-α levels following the FST exposure. ASP dose-dependently decreased FST-induced increase of cytokine levels, as manifested by significantly stronger effects on IL-6 and TNF-α levels at higher doses (25 and 50mg/kg) than the lowest dose of ASP (6 mg/kg). In all, these results indicate that ASP treatment dose-dependently decreased the immobility time and the release of pro-inflammatory cytokines in the FST, suggesting that the anti-inflammatory effects of ASP might be involved in the antidepressant-like effect

  14. Evaluation of antidepressant like property of amisulpride per se and its comparison with fluoxetine and olanzapine using forced swimming test in albino mice.

    Science.gov (United States)

    Pawar, Ganesh R; Agrawal, Rajendra P; Phadnis, Pradeep; Paliwal, Abhay; Vyas, Savita; Solanki, Pooja

    2009-01-01

    Amisulpride, an atypical antipsychotic was evaluated for antidepressant like activity in forced swimming test in Swiss albino mice. The effect of amisulpride was compared with that of fluoxetine, the standard antidepressant and olanzapine, another atypical antipsychotic claimed to have antidepressant like activity. Both acute and chronic studies were carried out. In both the studies, animals were divided into four groups (n = 8 each) and subjected to oral drug interventions as follows -- Group 1- control (distilled water, 1 mL/kg); Group 2- fluoxetine in a dose of 10 mg/kg 23.5, 5 and 1 h before the test; Group 3-amisulpride in a dose of 70 mg/kg 23.5, 5 and 1 h before the test; Group 4- olanzapine in a dose of 2 mg/kg 23.5, 5 and 1 h before the study. In the chronic study, the treatment was given daily for 28 days with last dose being given 2 h prior to the test. A time sampling method was used to score the behavioral activity in each group. Results of both the studies indicated that animals given amisulpride displayed significant improvement in swimming behavior (p Fluoxetine also showed significant difference in activity as compared to amisulpride and olanzapine (p swimming phases in albino mice (p > 0.05). We conclude that amisulpride per se has an antidepressant like activity comparable to that of olanzapine though the activity was significantly less than that of fluoxetine.

  15. Swimming activity in marine fish.

    Science.gov (United States)

    Wardle, C S

    1985-01-01

    Marine fish are capable of swimming long distances in annual migrations; they are also capable of high-speed dashes of short duration, and they can occupy small home territories for long periods with little activity. There is a large effect of fish size on the distance fish migrate at slow swimming speeds. When chased by a fishing trawl the effect of fish size on swimming performance can decide their fate. The identity and thickness of muscle used at each speed and evidence for the timing of myotomes used during the body movement cycle can be detected using electromyogram (EMG) electrodes. The cross-sectional area of muscle needed to maintain different swimming speeds can be predicted by relating the swimming drag force to the muscle force. At maximum swimming speed one completed cycle of swimming force is derived in sequence from the whole cross-sectional area of the muscles along the two sides of the fish. This and other aspects of the swimming cycle suggest that each myotome might be responsible for generating forces involved in particular stages of the tail sweep. The thick myotomes at the head end shorten during the peak thrust of the tail blade whereas the thinner myotomes nearer the tail generate stiffness appropriate for transmission of these forces and reposition the tail for the next cycle.

  16. The relationship between anxiety and depression in animal models: a study using the forced swimming test and elevated plus-maze

    Directory of Open Access Journals (Sweden)

    R. Andreatini

    1999-09-01

    Full Text Available The present study evaluated the correlation between the behavior of mice in the forced swimming test (FST and in the elevated plus-maze (PM. The effect of the order of the experiments, i.e., the influence of the first test (FST or PM on mouse behavior in the second test (PM or FST, respectively was compared to handled animals (HAND. The execution of FST one week before the plus-maze (FST-PM, N = 10, in comparison to mice that were only handled (HAND-PM, N = 10 in week 1, decreased % open entries (HAND-PM: 33.6 ± 2.9; FST-PM: 20.0 ± 3.9; mean ± SEM; P0.10. A prior test in the plus-maze (PM-FST did not change % immobility time in the FST when compared to the HAND-FST group (HAND-FST: 57.7 ± 3.9; PM-FST: 65.7 ± 3.2; mean ± SEM; P>0.10. Since these data suggest that there is an order effect, the correlation was evaluated separately with each test sequence: FST-PM (N = 20 and PM-FST (N = 18. There was no significant correlation between % immobility time in the FST and plus-maze indexes (% time and entries in open arms in any test sequence (r: -0.07 to 0.18. These data suggest that mouse behavior in the elevated plus-maze is not related to behavior in the forced swimming test and that a forced swimming test before the plus-maze has an anxiogenic effect even after a one-week interval.

  17. Antidepressant-like effect of a Ginkgo biloba extract (EGb761) in the mouse forced swimming test: role of oxidative stress.

    Science.gov (United States)

    Rojas, Patricia; Serrano-García, Norma; Medina-Campos, Omar N; Pedraza-Chaverri, José; Ogren, Sven O; Rojas, Carolina

    2011-10-01

    EGb761 is a well-defined mixture of active compounds extracted from Ginkgo biloba leaves. This extract is used clinically due to its neuroprotective effects, exerted probably via its potent antioxidant or free radical scavenger action. Previous studies suggest that oxidative stress, via free radical production, may play an important role in depression and animal models for depression-like behavior. Preclinical studies have suggested that antioxidants may have antidepressants properties. The aim of this study was to investigate the antidepressant-like of EGb761 due to its antioxidant role against oxidative stress induced in the forced swimming test, the most widely used preclinical model for assessing antidepressant-like behavior. Male BALB/c mice were pretreated with EGb761 (10mg/kg, ip) daily for 17 days followed by the forced swimming test and spontaneous locomotor activity. Animals were sacrificed to evaluate lipid peroxidation, different antioxidant enzyme activities, serotonin and dopamine content in midbrain, hippocampus and prefrontal cortex. EGb761 significantly decreased the immobility time (39%) in the forced swimming test. This antidepressant-like effect of EGb761 was associated with a reduction in lipid peroxidation and superoxide radical production (indicated by a downregulation of Mn-superoxide dismutase activity), both of which are indicators of oxidative stress. The protective effect of EGb761 is not related to excitatory or inhibitory effects in locomotor activity, and was also associated with the modulation of serotonergic and dopaminergic neurotransmission. It is suggested that EGb761 produces an antidepressant-like effect, and that an antioxidant effect against oxidative stress may be partly responsible for its observed neuroprotective effects. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Antidepressant-like effect of m-trifluoromethyl-diphenyl diselenide in the mouse forced swimming test involves opioid and serotonergic systems.

    Science.gov (United States)

    Brüning, César Augusto; Souza, Ana Cristina Guerra; Gai, Bibiana Mozzaquatro; Zeni, Gilson; Nogueira, Cristina Wayne

    2011-05-11

    Serotonergic and opioid systems have been implicated in major depression and in the action mechanism of antidepressants. The organoselenium compound m-trifluoromethyl-diphenyl diselenide (m-CF(3)-PhSe)(2) shows antioxidant and anxiolytic activities and is a selective inhibitor of monoamine oxidase A activity. The present study was designed to investigate the antidepressant-like effect of (m-CF(3)-PhSe)(2) in female mice, employing the forced swimming test. The involvement of the serotonergic and opioid systems in the antidepressant-like effect of (m-CF(3)-PhSe)(2) was appraised. (m-CF(3)-PhSe)(2) at doses of 50 and 100mg/kg (p.o.) exhibited antidepressant-like action in the forced swimming test. The effect of (m-CF(3)-PhSe)(2) (50mg/kg p.o.) was prevented by pretreatment of mice with WAY100635 (0.1mg/kg, s.c. a selective 5-HT(1A) receptor antagonist), ritanserin (4 mg/kg, i.p., a non-selective 5HT(2A/2C) receptor antagonist), ondansetron (1mg/kg, i.p., a selective 5-HT(3) receptor antagonist) and naloxone (1mg/kg, i.p., a non-selective antagonist of opioid receptors). These results suggest that (m-CF(3)-PhSe)(2) produced an antidepressant-like effect in the mouse forced swimming test and this effect seems most likely to be mediated through an interaction with serotonergic and opioid systems. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Evaluation of the effect of ethanolic extract of fruit pulp of Cassia fistula Linn. on forced swimming induced chronic fatigue syndrome in mice.

    Science.gov (United States)

    Sarma, P; Borah, M; Das, S

    2015-01-01

    The fruit of Cassia fistula Linn. is a legume, has antioxidant and lots of other medicinal properties. As oxidants are involved in the pathogenesis of chronic fatigue syndrome, the present study was done to evaluate the effect of ethanolic extract of fruit pulp of C. fistula Linn. (EECF) on forced swimming induced chronic fatigue syndrome (CFS). Albino mice of 25-40 grams were grouped into five groups (n=5). Group A served as naive control and group B served as stress control. Group C received EECF 200 mg/kg and group D received EECF 400 mg/kg respectively. Group E received imipramine 20 mg/kg (standard). All animals were treated with their respective agent orally daily for 7 days. Except for group A, animals in other groups were subjected to force swimming 6 min daily for 7 days to induce a state of chronic fatigue. Duration of immobility was assessed on day 1(st), 3(rd), 5(th) and 7(th). Anxiety level (by elevated plus maze and mirrored chamber) and loco-motor activity (by open field test) were assessed 24 h after last force swimming followed by biochemical estimations of oxidative biomarkers in brain homogenate at the end of study. Treatment with EECF resulted in significant reduction in the duration of immobility, reduced anxiety and increased loco-motor activity. Malondialdehyde level was also reduced and catalase level was increased in the extract treated group and standard group compared to stress control group. The study indicates that EECF has protective effect against experimentally induced CFS.

  20. Antidepressant-like effects of nicotinic acetylcholine receptor antagonists, but not agonists, in the mouse forced swim and mouse tail suspension tests

    DEFF Research Database (Denmark)

    Andreasen T., Jesper; Olsen, G M; Wiborg, O

    2009-01-01

    Current literature suggests involvement of nicotinic acetylcholine receptors (nAChRs) in major depression. However, it is controversial whether the antidepressant-like effect of nAChR modulation is induced by activation, desensitization or inhibition of central nAChRs. In addition, the specific n......AChR subtype/s involved remains unknown. In this study, we systematically compared the effects of non-selective and selective nicotinic agonists and antagonists in two different tests for antidepressant effects in mice: the tail suspension test and the forced swim test. Compounds: nicotine, RJR-2403 (alpha4...

  1. Attenuation of pCREB and Egr1 expression in the insular and anterior cingulate cortices associated with enhancement of CFA-evoked mechanical hypersensitivity after repeated forced swim stress.

    Science.gov (United States)

    Imbe, Hiroki; Kimura, Akihisa

    2017-09-01

    The perception and response to pain are severely impacted by exposure to stressors. In some animal models, stress increases pain sensitivity, which is termed stress-induced hyperalgesia (SIH). The insular cortex (IC) and anterior cingulate cortex (ACC), which are typically activated by noxious stimuli, affect pain perception through the descending pain modulatory system. In the present study, we examined the expression of phospho-cAMP response element-binding protein (pCREB) and early growth response 1 (Egr1) in the IC and ACC at 3h (the acute phase of peripheral tissue inflammation) after complete Freund's adjuvant (CFA) injection in naïve rats and rats preconditioned with forced swim stress (FS) to clarify the effect of FS, a stressor, on cortical cell activities in the rats showing SIH induced by FS. The CFA injection into the hindpaw induced mechanical hypersensitivity and increased the expression of the pCREB and Egr1 in the IC and ACC at 3h after the injection. FS (day 1, 10min; days 2-3, 20min) prior to the CFA injection enhanced the CFA-induced mechanical hypersensitivity and attenuated the increase in the expression of pCREB and Egr1 in the IC and ACC. These findings suggested that FS modulates the CFA injection-induced neuroplasticity in the IC and ACC to enhance the mechanical hypersensitivity. These findings are thought to signify stressor-induced dysfunction of the descending pain modulatory system. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. No evidence for a bioenergetic advantage from forced swimming in rainbow trout under a restrictive feeding regime

    DEFF Research Database (Denmark)

    Skov, Peter Vilhelm; Lund, Ivar; Margarido Pargana, Alexandre

    2015-01-01

    during a 15 week growth experiment, in which fish were reared at three different current speeds: 1 BL s(-1), 0.5 BL s(-1) and still water (approximate to 0 BL s(-1)). Randomly selected groups of 100 fish were distributed among twelve 600 L tanks and maintained on a restricted diet regime. Specific growth...... rate (SGR) and feed conversion ratio (FCR) were calculated from weight and length measurements every 3 weeks. Routine metabolic rate (RMR) was measured every hour as rate of oxygen consumption in the tanks, and was positively correlated with swimming speed. Total ammonia nitrogen (TAN) excretion rates...

  3. Test-retest paradigm of the forced swimming test in female mice is not valid for predicting antidepressant-like activity: participation of acetylcholine and sigma-1 receptors.

    Science.gov (United States)

    Su, Jing; Hato-Yamada, Noriko; Araki, Hiroaki; Yoshimura, Hiroyuki

    2013-01-01

    The forced swimming test (FST) in mice is widely used to predict the antidepressant activity of a drug, but information describing the immobility of female mice is limited. We investigated whether a prior swimming experience affects the immobility duration in a second FST in female mice and whether the test-retest paradigm is a valid screening tool for antidepressants. Female ICR mice were exposed to the FST using two experimental paradigms: a single FST and a double FST in which mice had experienced FST once 24 h prior to the second trail. The initial FST experience reliably prolonged immobility duration in the second FST. The antidepressants imipramine and paroxetine significantly reduced immobility duration in the single FST, but not in the double FST. Scopolamine and the sigma-1 (σ1) antagonist NE-100 administered before the second trial significantly prevented the prolongation of immobility. Neither a 5-HT1A nor a 5-HT2A receptor agonist affected immobility duration. We suggest that the test-retest paradigm in female mice is not adequate for predicting antidepressant-like activity of a drug; the prolongation of immobility in the double FST is modulated through acetylcholine and σ1 receptors.

  4. Anti-fatigue and vasoprotective effects of quercetin-3-O-gentiobiose on oxidative stress and vascular endothelial dysfunction induced by endurance swimming in rats.

    Science.gov (United States)

    Lin, Yin; Liu, Hua-Liang; Fang, Jie; Yu, Chen-Huan; Xiong, Yao-Kang; Yuan, Ke

    2014-06-01

    Chronic fatigue accumulation increases the incidence of cardiovascular disease while the treatment of antioxidants could prevent this development. We have previously shown that quercetin-3-O-gentiobiose (QG), a flavonoid isolated from tonic herb Okra, possesses anti-oxidative properties. In the present study, the protective effects of QG were evaluated in a rat model of load-induced endurance swimming. Oral administration of QG at the doses of 25-75mg/kg could significantly improve the endurance capability of rats to fatigue along with decrease serum lactic acid and blood urea nitrogen levels were decreased. Moreover, QG could alleviate vascular impairments, enhance the activities of antioxidant enzymes and attenuate the levels of inflammatory cytokines (MCP-1, IL-6 and TNF-α). The results indicated that QG had anti-fatigue and vasoprotective effects and represented a potential agent for the treatment of aortic pathology involved with fatigue- and related syndrome. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Evaluation of the role of NMDA receptor function in antidepressant-like activity. A new study with citalopram and fluoxetine in the forced swim test in mice.

    Science.gov (United States)

    Wolak, Małgorzata; Siwek, Agata; Szewczyk, Bernadeta; Poleszak, Ewa; Bystrowska, Beata; Moniczewski, Andrzej; Rutkowska, Anita; Młyniec, Katarzyna; Nowak, Gabriel

    2015-06-01

    The NMDA/glutamate receptors are involved in the mechanism of antidepressant activity. The present study was designed to investigate the effect of NMDA receptor ligands (agonists and antagonists of glutamate sites) on the antidepressant-like activity of selective serotonin reuptake inhibitors (SSRIs), citalopram and fluoxetine, in the forced swim test in mice. The antidepressant activity (reduction in immobility time) of citalopram but not of fluoxetine was antagonized by N-methyl-D-aspartate acid and enhanced by CGP37849 (antagonist of the NMDA receptor). The present literature data indicate that the antidepressant-like activity of conventional antidepressants is generally affected by the NMDA receptor, although by modulation from different sites of the complex. Thus, it supports the issue of the ability of NMDA receptor antagonists to enhance the antidepressant action in human depression. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  6. Nicotine, but not mecamylamine, enhances antidepressant-like effects of citalopram and reboxetine in the mouse forced swim and tail suspension tests

    DEFF Research Database (Denmark)

    Andreasen T., Jesper; Redrobe, John P

    2009-01-01

    and 10mg/kg citalopram and 3 and 10mg/kg reboxetine in the mTST. No concomitant locomotor stimulation was observed at the tested dose combinations. Mecamylamine was effective on its own in some tests, but did not augment the effects of citalopram or reboxetine at the doses tested. The data show...... activity and facilitates serotonin and noradrenaline release. Thus, we hypothesise that nicotine may enhance the behavioural effects of serotonin (e.g., citalopram) and/or noradrenaline (e.g., reboxetine) reuptake inhibitors. Here, we tested if nicotine enhanced the activity of citalopram or reboxetine...... in the mouse forced swim test (mFST) and the mouse tail suspension test (mTST). The potential for mecamylamine to augment antidepressant drug action was also investigated. Sub-threshold and threshold doses of citalopram (3 and 10mg/kg) or reboxetine (3, 10 and 20mg/kg) were tested alone and in combination...

  7. Secondary Structure of Rat and Human Amylin across Force Fields.

    Directory of Open Access Journals (Sweden)

    Kyle Quynn Hoffmann

    Full Text Available The aggregation of human amylin has been strongly implicated in the progression of Type II diabetes. This 37-residue peptide forms a variety of secondary structures, including random coils, α-helices, and β-hairpins. The balance between these structures depends on the chemical environment, making amylin an ideal candidate to examine inherent biases in force fields. Rat amylin differs from human amylin by only 6 residues; however, it does not form fibrils. Therefore it provides a useful complement to human amylin in studies of the key events along the aggregation pathway. In this work, the free energy of rat and human amylin was determined as a function of α-helix and β-hairpin content for the Gromos96 53a6, OPLS-AA/L, CHARMM22/CMAP, CHARMM22*, Amberff99sb*-ILDN, and Amberff03w force fields using advanced sampling techniques, specifically bias exchange metadynamics. This work represents a first systematic attempt to evaluate the conformations and the corresponding free energy of a large, clinically relevant disordered peptide in solution across force fields. The NMR chemical shifts of rIAPP were calculated for each of the force fields using their respective free energy maps, allowing us to quantitatively assess their predictions. We show that the predicted distribution of secondary structures is sensitive to the choice of force-field: Gromos53a6 is biased towards β-hairpins, while CHARMM22/CMAP predicts structures that are overly α-helical. OPLS-AA/L favors disordered structures. Amberff99sb*-ILDN, AmberFF03w and CHARMM22* provide the balance between secondary structures that is most consistent with available experimental data. In contrast to previous reports, our findings suggest that the equilibrium conformations of human and rat amylin are remarkably similar, but that subtle differences arise in transient alpha-helical and beta-strand containing structures that the human peptide can more readily adopt. We hypothesize that these transient

  8. Effects of ketamine and N-methyl-D-aspartate on fluoxetine-induced antidepressant-related behavior using the forced swimming test.

    Science.gov (United States)

    Owolabi, Rotimi Adegbenga; Akanmu, Moses Atanda; Adeyemi, Oluwole Isaac

    2014-04-30

    This study investigated the effects of ketamine on fluoxetine-induced antidepressant behavior using the forced swimming test (FST) in mice. In order to understand the possible role of N-methyl-d-aspartate (NMDA) neurotransmission in the antidepressant effect of fluoxetine, different groups of mice (n=10) were administered with acute ketamine (3mg/kg, i.p.), acute NMDA (75mg/kg and 150mg/kg, i.p.) and a 21-day chronic ketamine (15mg/kg, i.p./day) were administered prior to the administration of fluoxetine (20mg/kg, i.p.) in the mice. Antidepressant related behavior (immobility score) was measured using the forced swimming test. The results showed that the acute ketamine and fluoxetine alone treatments elicited a significant (pfluoxetine-induced decrease in immobility score. In contrast, pre-treatment with NMDA (150mg/kg) significantly (pfluoxetine-induced decrease in immobility score. On the other hand, chronic administration of ketamine significantly elicited an increase in immobility score as well as reversed the reduction induced by fluoxetine. Similarly, NMDA administration at both 75mg/kg and 150mg/kg increased immobility score in chronically administered ketamine groups. Furthermore, chronic administration of ketamine, followed by NMDA (75mg/kg) and fluoxetine significantly elevated the immobility score when compared with the group that received NMDA and fluoxetine but not chronically treated with ketamine. It can be suggested) that facilitation of NMDA transmission blocked fluoxetine-induced reduction in immobility score, while down-regulation of NMDA transmission is associated with increase in fluoxetine-induced antidepressant-related behavior in mice. Down-regulation of the NMDA transmission is proposed as an essential component of mechanism of suppression of depression related behaviors by fluoxetine. Modulation of NMDA transmission is suggested to be relevant in the mechanism of action of fluoxetine. Copyright © 2014 Elsevier Ireland Ltd. All rights

  9. Dopamine D2/D3 but not dopamine D1 receptors are involved in the rapid antidepressant-like effects of ketamine in the forced swim test.

    Science.gov (United States)

    Li, Yan; Zhu, Zhuo R; Ou, Bao C; Wang, Ya Q; Tan, Zhou B; Deng, Chang M; Gao, Yi Y; Tang, Ming; So, Ji H; Mu, Yang L; Zhang, Lan Q

    2015-02-15

    Major depressive disorder is one of the most prevalent and life-threatening forms of mental illnesses. The traditional antidepressants often take several weeks, even months, to obtain clinical effects. However, recent clinical studies have shown that ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, exerts rapid antidepressant effects within 2h and are long-lasting. The aim of the present study was to investigate whether dopaminergic system was involved in the rapid antidepressant effects of ketamine. The acute administration of ketamine (20 mg/kg) significantly reduced the immobility time in the forced swim test. MK-801 (0.1 mg/kg), the more selective NMDA antagonist, also exerted rapid antidepressant-like effects. In contrast, fluoxetine (10 mg/kg) did not significantly reduced the immobility time in the forced swim test after 30 min administration. Notably, pretreatment with haloperidol (0.15 mg/kg, a nonselective dopamine D2/D3 antagonist), but not SCH23390 (0.04 and 0.1 mg/kg, a selective dopamine D1 receptor antagonist), significantly prevented the effects of ketamine or MK-801. Moreover, the administration of sub-effective dose of ketamine (10 mg/kg) in combination with pramipexole (0.3 mg/kg, a dopamine D2/D3 receptor agonist) exerted antidepressant-like effects compared with each drug alone. In conclusion, our results indicated that the dopamine D2/D3 receptors, but not D1 receptors, are involved in the rapid antidepressant-like effects of ketamine. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Possible involvement of ATP-sensitive potassium channels in the antidepressant-like effect of baclofen in mouse forced swimming test.

    Science.gov (United States)

    Nazari, Seyedeh Khadijeh; Nikoui, Vahid; Ostadhadi, Sattar; Chegini, Zahra Hadi; Oryan, Shahrbanoo; Bakhtiarian, Azam

    2016-12-01

    Previous study confirmed that the acute treatment with baclofen by inhibition of the l-arginine-nitric oxide (NO) pathway diminished the immobility behavior in the forced swimming test (FST) of mice. Considering the involvement of NO in adenosine triphosphate (ATP)-sensitive potassium channels (K ATP ), in the present study we investigated the involvement of K ATP channels in antidepressant-like effect of baclofen in the forced swimming test (FST). After assessment of locomotor behavior in the open-field test (OFT), FST was applied for evaluation of the antidepressant-like activity of baclofen in mice. Baclofen at different doses (0.1, 0.3, and 1mg/kg) and fluoxetine (20mg/kg) were administrated by intraperitoneal (ip) route, 30min before the FST or OFT. To clarify the probable involvement of K ATP channels, after determination of sub-effective doses of glibenclamide as a K ATP channel blocker and cromakalim, as an opener of these channels, they were co-administrated with the sub-effective and effective doses of baclofen, respectively. Baclofen at dose 1mg/kg significantly decreased the immobility behavior of mice similar to fluoxetine (20mg/kg). Co-administration of gelibenclamide sub-effective dose (1mg/kg) with baclofen (0.1mg/kg) showed a synergistic antidepressant-like effect in the FST. Also, sub-effective dose of cromakalim (0.1mg/kg) inhibited the antidepressant-like effect of baclofen (1mg/kg) in the FST. All aforementioned treatments had not any impact on the locomotor movement of mice in OFT. Our study for the first time revealed that antidepressant-like effect of baclofen on mice is K ATP -dependent, and baclofen seems that exert this effect by blocking the K ATP channels. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  11. Repeated stress exposure causes strain-dependent shifts in the behavioral economics of cocaine in rats

    NARCIS (Netherlands)

    Groblewski, Peter A.; Zietz, Chad; Willuhn, Ingo; Phillips, Paul E. M.; Chavkin, Charles

    2015-01-01

    Cocaine-experienced Wistar and Wistar Kyoto (WKY) rats received four daily repeated forced swim stress sessions (R-FSS), each of which preceded 4-hour cocaine self-administration sessions. Twenty-four hours after the last swim stress, cocaine valuation was assessed during a single-session threshold

  12. Performance of four different rat strains in the autoshaping, two-object discrimination, and swim maze tests of learning and memory.

    Science.gov (United States)

    Andrews, J S; Jansen, J H; Linders, S; Princen, A; Broekkamp, C L

    1995-04-01

    The performance of four strains of rats commonly used in behavioural research was assessed in three different tests of learning and memory. The four strains included three outbred lines (Long-Evans, Sprague-Dawley, Wistar) and one inbred strain (S3). Learning and memory were tested using three different paradigms: autoshaping of a lever press, a two-object discrimination test, and performance in a two-island swim maze task. The pigmented strains showed better performance in the autoshaping procedure: the majority of the Long-Evans and the S3 rats acquired the response, and the majority of the Wistar and Sprague-Dawley failed to acquire the response in the set time. The albino strains were slightly better in the swim maze than the pigmented strains. There appeared to be a speed/accuracy trade-off in the strategy used to solve the task. This was also evident following treatment with the cholinergic-depleting agent hemicholinium-3. The performance of the Long-Evans rats was most affected by the treatment in terms of accuracy and the Wistar and Sprague-Dawleys in terms of speed. In the two-object discrimination test only the Long-Evans showed satisfactory performance and were able to discriminate a novel from a known object a short interval after initial exposure. These results show large task- and strain-dependent differences in performance in tests of learning and memory. Some of the performance variation may be due to emotional differences between the strains and may be alleviated by extra training. However, the response to pharmacological manipulation may require more careful evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. The effect of low-level laser therapy on oxidative stress and functional fitness in aged rats subjected to swimming: an aerobic exercise.

    Science.gov (United States)

    Guaraldo, Simone A; Serra, Andrey Jorge; Amadio, Eliane Martins; Antônio, Ednei Luis; Silva, Flávio; Portes, Leslie Andrews; Tucci, Paulo José Ferreira; Leal-Junior, Ernesto Cesar Pinto; de Carvalho, Paulo de Tarso Camillo

    2016-07-01

    The aim of the present study was to determine whether low-level laser therapy (LLLT) in conjunction with aerobic training interferes with oxidative stress, thereby influencing the performance of old rats participating in swimming. Thirty Wistar rats (Norvegicus albinus) (24 aged and six young) were tested. The older animals were randomly divided into aged-control, aged-exercise, aged-LLLT, aged-LLLT/exercise, and young-control. Aerobic capacity (VO2max(0.75)) was analyzed before and after the training period. The exercise groups were trained for 6 weeks, and the LLLT was applied at 808 nm and 4 J energy. The rats were euthanized, and muscle tissue was collected to analyze the index of lipid peroxidation thiobarbituric acid reactive substances (TBARS), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activities. VO2 (0.75)max values in the aged-LLLT/exercise group were significantly higher from those in the baseline older group (p exercise group (p exercise group than those in the LLLT and exercise groups. Young animals presented lesser and statistically significant activities of antioxidant enzymes compared to the aged group. The LLLT/exercise group and the LLLT and exercise group could also mitigate the concentration of TBARS (p > 0.05). Laser therapy in conjunction with aerobic training may reduce oxidative stress, as well as increase VO2 (0.75)max, indicating that an aerobic exercise such as swimming increases speed and improves performance in aged animals treated with LLLT.

  14. Opioid/NMDA receptors blockade reverses the depressant-like behavior of foot shock stress in the mouse forced swimming test.

    Science.gov (United States)

    Haj-Mirzaian, Arya; Ostadhadi, Sattar; Kordjazy, Nastaran; Dehpour, Ahmad Reza; Ejtemaei Mehr, Shahram

    2014-07-15

    Opioid and glutamatergic receptors have a key role in depression following stress. In this study, we assessed opioid and glutamatergic receptors interaction with the depressant-like behavior of acute foot-shock stress in the mouse forced swimming test. Stress was induced by intermittent foot shock stimulation during 30min and swim periods were afterwards conducted by placing mice in separated glass cylinders filled with water for 6min. The immobility time during the last 4min of the test was considered. Acute foot-shock stress significantly increased the immobility time of mice compared to non-stressed control group (P≤0.01). Administration of non-selective opioid receptors antagonist, naltrexone (1 and 2mg/kg, i.p.), and the selective non-competitive NMDA receptor antagonist, MK-801 (0.05mg/kg, i.p.), and the selective serotonin reuptake inhibitor, fluoxetine (5mg/kg), significantly reduced the immobility time in stressed animals (P≤0.01). Lower doses of MK-801 (0.01mg/kg), naltrexone (0.3mg/kg), NMDA (75mg/kg) and morphine(5mg/kg) had no effect on foot-shock stressed mice. Combined treatment of sub-effective doses of naltrexone and MK-801 significantly showed an antidepressant-like effect (P≤0.001). On the other hand, co-administration of non-effective doses of NMDA and morphine with effective doses of naltrexone and MK-801 reversed the anti-immobility effect of these drugs. Taken together, we have for the first time demonstrated the possible role of opioid/NMDA receptors signaling in the depressant-like effect of foot-shock stress, and proposed the use of drugs that act like standard anti-depressants in stress-induced depression. Copyright © 2014. Published by Elsevier B.V.

  15. Long-term aerobic swimming training by rats reduces the number of aberrant crypt foci in 1,2-dimethylhydrazine-induced colon cancer

    Directory of Open Access Journals (Sweden)

    W. Lunz

    2008-11-01

    Full Text Available We determined the effect of long-term aerobic swimming training regimens of different intensities on colonic carcinogenesis in rats. Male Wistar rats (11 weeks old were given 4 subcutaneous injections (40 mg/kg body weight each of 1,2-dimethyl-hydrazine (DMH, dissolved in 0.9% NaCl containing 1.5% EDTA, pH 6.5, at 3-day intervals and divided into three exercise groups that swam with 0% body weight (EG1, N = 11, 2% body weight (EG2, N = 11, and 4% body weight of load (EG3, N = 10, 20 min/day, 5 days/week for 35 weeks, and one sedentary control group (CG, N = 10. At sacrifice, the colon was removed and counted for tumors and aberrant crypt foci. Tumor size was measured and intra-abdominal fat was weighed. The mean number of aberrant crypt foci was reduced only for EG2 compared to CG (26.21 ± 2.99 vs 36.40 ± 1.53 crypts; P < 0.05. Tumor incidence was not significantly different among groups (CG: 90%; EG1: 72.7%; EG2: 90%; EG3: 80%. Swimming training did not affect either tumor multiplicity (CG: 2.30 ± 0.58; EG1: 2.09 ± 0.44; EG2: 1.27 ± 0.19; EG3: 1.50 ± 0.48 tumors or size (CG: 1.78 ± 0.24; EG1: 1.81 ± 0.14; EG2: 1.55 ± 0.21; EG3: 2.17 ± 0.22 cm³. Intra-abdominal fat was not significantly different among groups (CG: 10.54 ± 2.73; EG1: 6.12 ± 1.15; EG2: 7.85 ± 1.24; EG3: 5.11 ± 0.74 g. Aerobic swimming training with 2% body weight of load protected against the DMH-induced preneoplastic colon lesions, but not against tumor development in the rat.

  16. Chronic Swimming Exercise Ameliorates Low-Soybean-Oil Diet-Induced Spatial Memory Impairment by Enhancing BDNF-Mediated Synaptic Potentiation in Developing Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Cheng, Mei; Cong, Jiyan; Wu, Yulong; Xie, Jiacun; Wang, Siyuan; Zhao, Yue; Zang, Xiaoying

    2018-05-01

    Exercise and low-fat diets are common lifestyle modifications used for the treatment of hypertension besides drug therapy. However, unrestrained low-fat diets may result in deficiencies of low-unsaturated fatty acids and carry contingent risks of delaying neurodevelopment. While aerobic exercise shows positive neuroprotective effects, it is still unclear whether exercise could alleviate the impairment of neurodevelopment that may be induced by certain low-fat diets. In this research, developing spontaneously hypertensive rats (SHR) were treated with chronic swimming exercise and/or a low-soybean-oil diet for 6 weeks. We found that performance in the Morris water maze was reduced and long-term potentiation in the hippocampus was suppressed by the diet, while a combination treatment of exercise and diet alleviated the impairment induced by the specific low-fat diet. Moreover, the combination treatment effectively increased the expression of brain-derived neurotrophic factor (BDNF) and N-methyl-D-aspartic acid receptor (NMDAR), which were both down-regulated by the low-soybean-oil diet in the hippocampus of developing SHR. These findings suggest that chronic swimming exercise can ameliorate the low-soybean-oil diet-induced learning and memory impairment in developing SHR through the up-regulation of BDNF and NMDAR expression.

  17. Neurotrophic peptide ACTH-(4–10) permits glucocorticoid-facilitated retention of acquired immobility response of hypophysectomized rats

    NARCIS (Netherlands)

    Kock, S. de; Kloet, E.R. de

    1987-01-01

    The Porsolt swimming test, which was originally designed as an experimental model to screen potential antidepressants demands that rats be forced to swim for 15 min in a narrow cylinder. Twenty four hours later they are retested for 5 min during which they stay immobile for approximately 70% of the

  18. Differential involvement of 5-HT(1A) and 5-HT(1B/1D) receptors in human interferon-alpha-induced immobility in the mouse forced swimming test.

    Science.gov (United States)

    Zhang, Hongmei; Wang, Wei; Jiang, Zhenzhou; Shang, Jing; Zhang, Luyong

    2010-01-01

    Although Interferon-alpha (IFN-alpha, CAS 9008-11-1) is a powerful drug in treating several viral infections and certain tumors, a considerable amount of neuropsychiatric side-effects such as depression and anxiety are an unavoidable consequence. Combination with the selective serotonin (5-HT) reuptake inhibitor (SSRI) fluoxetine (CAS 56296-78-7) significantly improved the situation. However, the potential 5-HT(1A) receptor- and 5-HT(1B) receptor-signals involved in the antidepressant effects are still unclear. The effects of 5-HT(1A) receptor- and 5-HT(1B) receptor signals were analyzed by using the mouse forced swimming test (FST), a predictive test of antidepressant-like action. The present results indicated that (1) fluoxetine (administrated intragastrically, 30 mg/kg; not subactive dose: 15 mg/kg) significantly reduced IFN-alpha-induced increase of the immobility time in the forced swimming test; (2) 5-HT(1A) receptor- and 5-HT(1B) receptor ligands alone or in combination had no effects on IFN-alpha-induced increase of the immobility time in the FST; (3) surprisingly, WAY 100635 (5-HT(1A) receptor antagonist, 634908-75-1) and 8-OH-DPAT(5-HT(1A) receptor agonist, CAS 78950-78-4) markedly enhanced the antidepressant effect of fluoxetine at the subactive dose (15 mg/kg, i. g.) on the IFN-alpha-treated mice in the FST. Further investigations showed that fluoxetine combined with WAY 100635 and 8-OH-DPAT failed to produce antidepressant effects in the FST. (4) Co-application of CGS 12066A (5-HT(1B) receptor agonist, CAS 109028-09-3) or GR 127935 (5-HT(1B/1D) receptor antagonist, CAS 148642-42-6) with fluoxetine had no synergistic effects on the IFN-alpha-induced increase of immobility time in FST. (5) Interestingly, co-administration of GR 127935, WAY 100635 and fluoxetine significantly reduced the IFN-alpha-induced increase in immobility time of FST, being more effective than co-administration of WAY 100635 and fluoxetine. All results suggest that (1) compared to

  19. Free Swimming in Ground Effect

    Science.gov (United States)

    Cochran-Carney, Jackson; Wagenhoffer, Nathan; Zeyghami, Samane; Moored, Keith

    2017-11-01

    A free-swimming potential flow analysis of unsteady ground effect is conducted for two-dimensional airfoils via a method of images. The foils undergo a pure pitching motion about their leading edge, and the positions of the body in the streamwise and cross-stream directions are determined by the equations of motion of the body. It is shown that the unconstrained swimmer is attracted to a time-averaged position that is mediated by the flow interaction with the ground. The robustness of this fluid-mediated equilibrium position is probed by varying the non-dimensional mass, initial conditions and kinematic parameters of motion. Comparisons to the foil's fixed-motion counterpart are also made to pinpoint the effect that free swimming near the ground has on wake structures and the fluid-mediated forces over time. Optimal swimming regimes for near-boundary swimming are determined by examining asymmetric motions.

  20. Maternal separation increases later immobility during forced swim in guinea pig pups: evidence for sensitization of a depressive-like state.

    Science.gov (United States)

    Hennessy, Michael B; Schreibeis, Amanda D; Schiml, Patricia A; Deak, Terrence

    2017-01-01

    Early-life stress is thought to increase later vulnerability for developing depressive illness by sensitizing underlying stress-responsive systems. Guinea pig pups separated from their mother and isolated in a novel cage for 3 hr exhibit a sensitized depressive-like behavioral response when separated again the following day as well as weeks later. The behavioral response and its sensitization appear to be mediated by inflammatory factors. To determine if this sensitization is specific to the separation response or if it reflects a broader underlying depressive-like state, guinea pig pups that had either been separated for 3 hr or remained with their mothers were observed in the forced swim test the following 3 days. Earlier separation was found to increase the duration of immobility, a measure sensitive to antidepressant treatment. These results support the use of the guinea pig as a model for examining mechanisms of inflammatory-mediated sensitization of depression following stress in early life. © 2016 Wiley Periodicals, Inc.

  1. Antidepressant-like effect of fluoxetine may depend on translocator protein activity and pretest session duration in forced swimming test in mice.

    Science.gov (United States)

    Kudryashov, Nikita V; Kalinina, Tatiana S; Shimshirt, Alexander A; Korolev, Anton O; Volkova, Anna V; Voronina, Tatiana A

    2018-06-01

    The antidepressant-like effect of fluoxetine (20 mg/kg i.p.) has been assessed using the forced swimming test (FST) in IRC (CD-1) mice exposed or not to a pretest session of different duration (5 or 20 min). The influence of the mitochondrial translocator protein (TSPO) activity on the antidepressant-like effect of fluoxetine (20 mg/kg i.p.) in the FST was also studied. The antidepressant-like effect of fluoxetine was observed only in mice subjected to a 5-min pretest session 24 h before the FST. The TSPO antagonist PK11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide; 1 or 3 mg/kg i.p.] inhibited the antidepressant activity of fluoxetine in the FST. In the present study, fluoxetine or PK11195 was administered for a short duration. We suppose that the functional activity of TSPO may depend on a pretest session and that using this procedure is necessary to detect antidepressant activity of fluoxetine-like drugs.

  2. Effect of addition of yohimbine (alpha-2-receptor antagonist) to the antidepressant activity of fluoxetine or venlafaxine in the mouse forced swim test.

    Science.gov (United States)

    Dhir, Ashish; Kulkarni, S K

    2007-01-01

    Studies have suggested that alpha(2)-adrenoceptors strongly affect monoaminergic neurotransmission by enhancing not only noradrenergic but also serotonergic firing rates. With this background in mind, the present study was undertaken to monitor the effect of addition of yohimbine (alpha(2)-adrenoceptor antagonist) to the effect of fluoxetine (selective serotonin reuptake inhibitor) or venlafaxine (dual reuptake inhibitors of both serotonin and norepinephrine) in Porsolt's forced swim test (FST) using male Laca strain mice. The immobility period was recorded in mouse FST during a 6-min period. Different doses of fluoxetine or venlafaxine were administered 30 min before exposing the animals to the test procedure. In the combination study, yohimbine (2 mg/kg i.p.) was administered 15 min before the administration of different doses of fluoxetine or venlafaxine. Fluoxetine (5, 10, 20 and 40 mg/kg) [F = 28.352] or venlafaxine (2, 4, 8 and 16 mg/kg) [F = 17.842] dose-dependently inhibited the immobility period in mice. Addition of yohimbine (2 mg/kg i.p.) potentiated the antidepressant action of fluoxetine or venlafaxine in mouse FST as the animals showed a decrease in the immobility period compared to the fluoxetine or venlafaxine per se group, respectively. The present study not only demonstrated the association of alpha(2)-receptors in the antidepressant effect of fluoxetine or venlafaxine, but also supports its adjuvant therapy with other antidepressant drugs. (c) 2007 S. Karger AG, Basel.

  3. Possible involvement of ATP-sensitive potassium channels in the antidepressant-like effects of gabapentin in mouse forced swimming test.

    Science.gov (United States)

    Ostadhadi, Sattar; Akbarian, Reyhaneh; Norouzi-Javidan, Abbas; Nikoui, Vahid; Zolfaghari, Samira; Chamanara, Mohsen; Dehpour, Ahmad-Reza

    2017-07-01

    Gabapentin as an anticonvulsant drug also has beneficial effects in treatment of depression. Previously, we showed that acute administration of gabapentin produced an antidepressant-like effect in the mouse forced swimming test (FST) by a mechanism that involves the inhibition of nitric oxide (NO). Considering the involvement of NO in adenosine triphosphate (ATP)-sensitive potassium channels (K ATP ), in the present study we investigated the involvement of K ATP channels in antidepressant-like effect of gabapentin. Gabapentin at different doses (5-10 mg/kg) and fluoxetine (20 mg/kg) were administrated by intraperitoneal route, 60 and 30 min, respectively, before the test. To clarify the probable involvement of K ATP channels, mice were pretreated with K ATP channel inhibitor or opener. Gabapentin at dose 10 mg/kg significantly decreased the immobility behavior of mice similar to fluoxetine (20 mg/kg). Co-administration of subeffective dose (1 mg/kg) of glibenclamide (inhibitor of K ATP channels) with gabapentin (3 mg/kg) showed a synergistic antidepressant-like effect. Also, subeffective dose of cromakalim (opener of K ATP channels, 0.1 mg/kg) inhibited the antidepressant-like effect of gabapentin (10 mg/kg). None of the treatments had any impact on the locomotor movement. Our study, for the first time, revealed that antidepressant-like effect of gabapentin in mice is mediated by blocking the K ATP channels.

  4. Antidepressant-like activity of resveratrol treatment in the forced swim test and tail suspension test in mice: the HPA axis, BDNF expression and phosphorylation of ERK.

    Science.gov (United States)

    Wang, Zhen; Gu, Jianhua; Wang, Xueer; Xie, Kai; Luan, Qinsong; Wan, Nianqing; Zhang, Qun; Jiang, Hong; Liu, Dexiang

    2013-11-01

    Resveratrol is a natural polyphenol enriched in Polygonum cuspidatum and has diverse biological activities. There is only limited information about the antidepressant-like effect of resveratrol. The present study assessed whether resveratrol treatment (20, 40 and 80mg/kg, i.p., 21days) has an antidepressant-like effect on the forced swim test (FST) and tail suspension test (TST) in mice and examined what its molecular targets might be. The results showed that resveratrol administration produced antidepressant-like effects in mice, evidenced by the reduced immobility time in the FST and TST, while it had no effect on the locomotor activity in the open field test. Resveratrol treatment significantly reduced serum corticosterone levels, which had been elevated by the FST and TST. Moreover, resveratrol increased brain-derived neurotrophic factor (BDNF) protein and extracellular signal-regulated kinase (ERK) phosphorylation levels in the prefrontal cortex and hippocampus. All of these antidepressant-like effects of resveratrol were essentially similar to those observed with the clinical antidepressant, fluoxetine. These results suggest that the antidepressant-like effects of resveratrol in the FST and TST are mediated, at least in part, by modulating hypothalamic-pituitary-adrenal axis, BDNF and ERK phosphorylation expression in the brain region of mice. © 2013.

  5. A possible utilization of the mice forced swim test for modeling manic-like increase in vigor and goal-directed behavior.

    Science.gov (United States)

    Flaisher-Grinberg, Shlomit; Einat, Haim

    2009-01-01

    The lack of appropriate animal models for bipolar disorder (BPD) is a major factor hindering the research of its pathophysiology and the development of new drug treatments. In line with the notion that BPD might represent a heterogeneous group of disorders, it was suggested that models for specific domains of BPD should be developed. The present study tested the possible utilization of the forced swim test (FST) as a model for the heightened vigor and goal-directed behavior domain of mania, using mice with low baseline immobility. Black Swiss mice were previously identified to have low immobility in the FST but similar spontaneous activity levels compared with several other mice strains. Thus, spontaneous activity and behavior in the FST were evaluated following treatment with the mood stabilizer valproate and the antidepressant imipramine. The results indicated that valproate increased immobility in the FST without affecting spontaneous activity whereas imipramine had no effect in the FST but increased spontaneous activity. These findings suggest that in mice with low baseline immobility scores, the FST might be a useful model for the elevated vigor and goal-directed behavior domain of mania. As such, this test might be well integrated into a battery of models for different domains of BPD.

  6. Antidepressant-like effect of Hoodia gordonii in a forced swimming test in mice: evidence for involvement of the monoaminergic system

    Directory of Open Access Journals (Sweden)

    M.C.O. Citó

    2015-01-01

    Full Text Available Hoodia gordonii is a plant species used traditionally in southern Africa to suppress appetite. Recently, it has been associated with a significant increase in blood pressure and pulse rate in women, suggesting sympathomimetic activity. The present study investigated the possible antidepressant-like effects of acute and repeated (15 days administration of H. gordonii extract (25 and 50 mg/kg, po to mice exposed to a forced swimming test (FST. Neurochemical analysis of brain monoamines was also carried out to determine the involvement of the monoaminergic system on these effects. Acute administration of H. gordonii decreased the immobility of mice in the FST without accompanying changes in general activity in the open-field test during acute treatment, suggesting an antidepressant-like effect. The anti-immobility effect of H. gordonii was prevented by pretreatment of mice with PCPA [an inhibitor of serotonin (5-HT synthesis], NAN-190 (a 5-HT1A antagonist, ritanserin (a 5-HT2A/2C antagonist, ondansetron (a 5-HT3A antagonist, prazosin (an α1-adrenoceptor antagonist, SCH23390 (a D1 receptor antagonist, yohimbine (an α2-adrenoceptor antagonist, and sulpiride (a D2 receptor antagonist. A significant increase in 5-HT levels in the striatum was detected after acute administration, while 5-HT, norepinephrine and dopamine were significantly elevated after chronic treatment. Results indicated that H. gordonii possesses antidepressant-like activity in the FST by altering the dopaminergic, serotonergic, and noradrenergic systems.

  7. Phosphodiesterase-1b (Pde1b) knockout mice are resistant to forced swim and tail suspension induced immobility and show upregulation of Pde10a.

    Science.gov (United States)

    Hufgard, Jillian R; Williams, Michael T; Skelton, Matthew R; Grubisha, Olivera; Ferreira, Filipa M; Sanger, Helen; Wright, Mary E; Reed-Kessler, Tracy M; Rasmussen, Kurt; Duman, Ronald S; Vorhees, Charles V

    2017-06-01

    Major depressive disorder is a leading cause of suicide and disability. Despite this, current antidepressants provide insufficient efficacy in more than 60% of patients. Most current antidepressants are presynaptic reuptake inhibitors; postsynaptic signal regulation has not received as much attention as potential treatment targets. We examined the effects of disruption of the postsynaptic cyclic nucleotide hydrolyzing enzyme, phosphodiesterase (PDE) 1b, on depressive-like behavior and the effects on PDE1B protein in wild-type (WT) mice following stress. Littermate knockout (KO) and WT mice were tested in locomotor activity, tail suspension (TST), and forced swim tests (FST). FST was also used to compare the effects of two antidepressants, fluoxetine and bupropion, in KO versus WT mice. Messenger RNA (mRNA) expression changes were also determined. WT mice underwent acute or chronic stress and markers of stress and PDE1B expression were examined. Pde1b KO mice exhibited decreased TST and FST immobility. When treated with antidepressants, both WT and KO mice showed decreased FST immobility and the effect was additive in KO mice. Mice lacking Pde1b had increased striatal Pde10a mRNA expression. In WT mice, acute and chronic stress upregulated PDE1B expression while PDE10A expression was downregulated after chronic but not acute stress. PDE1B is a potential therapeutic target for depression treatment because of the antidepressant-like phenotype seen in Pde1b KO mice.

  8. The antidepressant-like effect of 7-fluoro-1,3-diphenylisoquinoline-1-amine in the mouse forced swimming test is mediated by serotonergic and dopaminergic systems.

    Science.gov (United States)

    Pesarico, Ana Paula; Sampaio, Tuane Bazanella; Stangherlin, Eluza Curte; Mantovani, Anderson C; Zeni, Gilson; Nogueira, Cristina Wayne

    2014-10-03

    The aim of the present study was to investigate the role of monoaminergic system in the antidepressant-like action of 7-fluoro-1,3-diphenylisoquinoline-1-amine (FDPI), a derivative of isoquinoline class, in Swiss mice. The antidepressant-like effect of FDPI was characterized in the modified forced swimming test (FST) and the possible mechanism of action was investigated by using serotonergic, dopaminergic and noradrenergic antagonists. Monoamine oxidase (MAO) activity and [(3)H]serotonin (5-HT) uptake were determined in prefrontal cortices of mice. The results showed that FDPI (1, 10 and 20mg/kg, i.g.) reduced the immobility time and increased the swimming time but did not alter climbing time in the modified FST. These effects were similar to those of paroxetine (8mg/kg, i.p.), a positive control. Pretreatments with p-chlorophenylalanine (100mg/kg, i.p., an inhibitor of 5-HT synthesis), WAY100635 (0.1mg/kg, s.c., 5-HT1A antagonist), ondansetron (1mg/kg, i.p., a 5-HT3 receptor antagonist), haloperidol (0.2mg/kg, i.p., a non-selective D2 receptor antagonist) and SCH23390 (0.05mg/kg, s.c., a D1 receptor antagonist) were effective to block the antidepressant-like effect of FDPI at a dose of 1mg/kg in the FST. Ritanserin (1mg/kg, i.p., a 5-HT2A/2C receptor antagonist), sulpiride (50mg/kg, i.p., a D2 and D3 receptor antagonist), prazosin (1mg/kg, i.p., an α1 receptor antagonist), yohimbine (1mg/kg, i.p., an α2 receptor antagonist) and propranolol (2mg/kg, i.p., a β receptor antagonist) did not modify the effect of FDPI in the FST. FDPI did not change synaptosomal [(3)H]5-HT uptake. At doses of 10 and 20mg/kg FDPI inhibited MAO-A and MAO-B activities. These results suggest that antidepressant-like effect of FDPI is mediated mostly by serotonergic and dopaminergic systems. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Anisotropic swim stress in active matter with nematic order

    Science.gov (United States)

    Yan, Wen; Brady, John F.

    2018-05-01

    Active Brownian particles (ABPs) transmit a swim pressure {{{\\Pi }}}{{swim}}=n\\zeta {D}{{swim}} to the container boundaries, where ζ is the drag coefficient, D swim is the swim diffusivity and n is the uniform bulk number density far from the container walls. In this work we extend the notion of the isotropic swim pressure to the anisotropic tensorial swim stress {{\\boldsymbol{σ }}}{{swim}}=-n\\zeta {{\\boldsymbol{D}}}{{swim}}, which is related to the anisotropic swim diffusivity {{\\boldsymbol{D}}}{{swim}}. We demonstrate this relationship with ABPs that achieve nematic orientational order via a bulk external field. The anisotropic swim stress is obtained analytically for dilute ABPs in both 2D and 3D systems. The anisotropy, defined as the ratio of the maximum to the minimum of the three principal stresses, is shown to grow exponentially with the strength of the external field. We verify that the normal component of the anisotropic swim stress applies a pressure {{{\\Pi }}}{{swim}}=-({{\\boldsymbol{σ }}}{{swim}}\\cdot {\\boldsymbol{n}})\\cdot {\\boldsymbol{n}} on a wall with normal vector {\\boldsymbol{n}}, and, through Brownian dynamics simulations, this pressure is shown to be the force per unit area transmitted by the active particles. Since ABPs have no friction with a wall, the difference between the normal and tangential stress components—the normal stress difference—generates a net flow of ABPs along the wall, which is a generic property of active matter systems.

  10. Anti-fatigue activity of sea cucumber peptides prepared from Stichopus japonicus in an endurance swimming rat model.

    Science.gov (United States)

    Ye, Jing; Shen, Caihong; Huang, Yayan; Zhang, Xueqin; Xiao, Meitian

    2017-10-01

    Sea cucumber (Stichopus japonicus) is a well-known nutritious and luxurious seafood in Asia which has attracted increasing attention because of its nutrition and bioactivities in recent years. In this study, the anti-fatigue activity of sea cucumber peptides (SCP) prepared from S. japonicus was evaluated in a load-induced endurance swimming model. The SCP prepared in this study was mainly made up of low-molecular-weight peptides (fatigue was significantly improved by SCP treatment. Meanwhile, the remarkable alterations of energy metabolic markers, antioxidant enzymes, antioxidant capacity and oxidative stress biomarkers were normalized. Moreover, administration of SCP could modulate alterations of inflammatory cytokines and downregulate the overexpression of TRL4 and NF-κB. SCP has anti-fatigue activity and it exerted its anti-fatigue effect probably through normalizing energy metabolism as well as alleviating oxidative damage and inflammatory responses. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  11. Antidepressant-like effects of nicotine and mecamylamine in the mouse forced swim and tail suspension tests: role of strain, test and sex

    DEFF Research Database (Denmark)

    Andreasen T., Jesper; Redrobe, John P

    2009-01-01

    , but not mecamylamine, increased swim distance in C57BL/6J mice. Both drugs increased swim distance in BALB/c mice. Effects in the mFST were independent of sex. In the mTST, mecamylamine decreased immobility in NMRI mice only, independent of sex. Nicotine was devoid of effects in the mTST, except in female C57BL/6J...

  12. Swimming training induces liver adaptations to oxidative stress and insulin sensitivity in rats submitted to high-fat diet.

    Science.gov (United States)

    Zacarias, Aline Cruz; Barbosa, Maria Andrea; Guerra-Sá, Renata; De Castro, Uberdan Guilherme Mendes; Bezerra, Frank Silva; de Lima, Wanderson Geraldo; Cardoso, Leonardo M; Santos, Robson Augusto Souza Dos; Campagnole-Santos, Maria José; Alzamora, Andréia Carvalho

    2017-11-01

    Oxidative stress, physical inactivity and high-fat (FAT) diets are associated with hepatic disorders such as metabolic syndrome (MS). The therapeutic effects of physical training (PT) were evaluated in rats with MS induced by FAT diet for 13 weeks, on oxidative stress and insulin signaling in the liver, during the last 6 weeks. FAT-sedentary (SED) rats increased body mass, retroperitoneal fat, mean arterial pressure (MAP) and heart rate (HR), and total cholesterol, serum alanine aminotransferase, glucose and insulin. Livers of FAT-SED rats increased superoxide dismutase activity, thiobarbituric acid-reactive substances, protein carbonyl and oxidized glutathione (GSSG); and decreased catalase activity, reduced glutathione/GSSG ratio, and the mRNA expression of insulin receptor substrate 1 (IRS-1) and serine/threonine kinase 2. FAT-PT rats improved in fitness and reduced their body mass, retroperitoneal fat, and glucose, insulin, total cholesterol, MAP and HR; and their livers increased superoxide dismutase and catalase activities, the reduced glutathione/GSSG ratio and the expression of peroxisome proliferator-activated receptor gamma and insulin receptor compared to FAT-SED rats. These findings indicated adaptive responses to PT by restoring the oxidative balance and insulin signaling in the liver and certain biometric and biochemical parameters as well as MAP in MS rats.

  13. Evidence for the involvement of NMDA receptors in the antidepressant-like effect of nicotine in mouse forced swimming and tail suspension tests.

    Science.gov (United States)

    Haj-Mirzaian, Arya; Kordjazy, Nastaran; Haj-Mirzaian, Arvin; Ostadhadi, Sattar; Ghasemi, Mehdi; Amiri, Shayan; Faizi, Mehrdad; Dehpour, AhmadReza

    2015-10-01

    The antidepressant action of acute nicotine administration in clinical and animal studies is well recognized. But the underlying mechanism for this effect has not been carefully discovered. We attempted to evaluate the possible role of N-Methyl-D-aspartate (NMDA) receptors in the antidepressant-like effect of nicotine. After the assessment of locomotor activity in the open-field test, forced swimming test (FST) and tail suspension test (TST) were used to evaluate the antidepressant-like effect of nicotine in mice. We performed intraperitoneal administration of nicotine at different doses and periods before the tests. To assess the possible involvement of NMDA receptors, non-effective doses of NMDA antagonists and an NMDA agonist were obtained and were administered simultaneously with the non-effective and effective doses of nicotine, respectively. Nicotine (0.2 mg/kg, 30 min before FST/TST) significantly reduced the immobility time of mice similar to fluoxetine (20 mg/kg). Nicotine did not affect the locomotor behavior of mice in open-field test. Co-administration of non-effective doses of NMDA receptor antagonists, ketamine (1 or 0.3 mg/kg), MK-801 (0.05 or 0.005 mg/kg), and magnesium sulfate (10 or 5 mg/kg) with nicotine (0.1 or 0.03 mg/kg) had remarkable synergistic antidepressant effect in both FST and TST. Also, non-effective NMDA (75 or 30 mg/kg) reversed the anti-immobility effect of nicotine (0.2 mg/kg) on mouse FST and TST. Our study has for the first time confirmed that the antidepressant-like effect of nicotine on mice is NMDA-mediated, and nicotine presumably exerts this effect by antagonizing the glutamatergic NMDA receptors.

  14. Involvement of N-methyl-d-aspartate receptors in the antidepressant-like effect of 5-hydroxytryptamine 3 antagonists in mouse forced swimming test and tail suspension test.

    Science.gov (United States)

    Kordjazy, Nastaran; Haj-Mirzaian, Arya; Amiri, Shayan; Ostadhadi, Sattar; Amini-Khoei, Hossein; Dehpour, Ahmad Reza

    2016-02-01

    Recent evidence indicates that 5-hydroxytryptamine 3 (5-HT3) antagonists such as ondansetron and tropisetron exert positive behavioral effects in animal models of depression. Due to the ionotropic nature of 5-HT3 and N-methyl-d-aspartate (NMDA) receptors, plus their contribution to the pathophysiology of depression, we investigated the possible role of NMDA receptors in the antidepressant-like effect of 5-HT3 receptor antagonists in male mice. In order to evaluate the animals' behavior in response to different treatments, we performed open-field test (OFT), forced swimming test (FST), and tail-suspension test (TST), which are considered as valid tasks for measuring locomotor activity and depressive-like behaviors in mice. Our data revealed that intraperitoneal (i.p.) administration of tropisetron (5, 10, and 30mg/kg) and ondansetron (0.01, and 0.1μg/kg) significantly decreased the immobility time in FST and TST. Also, co-administration of subeffective doses of tropisetron (1mg/kg, i.p.) or ondansetron (0.001μg/kg, i.p.) with subeffective doses of NMDA receptor antagonists, ketamine (1mg/kg, i.p.), MK-801 (0.05mg/kg, i.p.) and magnesium sulfate (10mg/kg, i.p.) resulted in a reduced immobility time both in FST and TST. The subeffective dose of NMDA (NMDA receptor agonist, 75mg/kg, i.p.) abolished the effects of 5-HT3 antagonists in FST and TST, further supporting the presumed interaction between 5-HT3 and NMDA receptors. These treatments did not affect the locomotor behavior of animals in OFT. Finally, the results of our study suggest that the positive effects of 5-HT3 antagonists on the coping behavior of mice in FST and TST are at least partly mediated through NMDA receptors participation. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Antidepressant-like effects of the cannabinoid receptor ligands in the forced swimming test in mice: mechanism of action and possible interactions with cholinergic system.

    Science.gov (United States)

    Kruk-Slomka, Marta; Michalak, Agnieszka; Biala, Grazyna

    2015-05-01

    The purpose of the experiments was to explore the role of the endocannabinoid system, through cannabinoid (CB) receptor ligands, nicotine and scopolamine, in the depression-related responses using the forced swimming test (FST) in mice. Our results revealed that acute injection of oleamide (10 and 20 mg/kg), a CB1 receptor agonist, caused antidepressant-like effect in the FST, while AM 251 (0.25-3 mg/kg), a CB1 receptor antagonist, did not provoke any effect in this test. Moreover, acute administration of both CB2 receptor agonist, JWH 133 (0.5 and 1 mg/kg) and CB2 receptor antagonist, AM 630 (0.5 mg/kg), exhibited antidepressant action. Antidepressant effects of oleamide and JWH 133 were attenuated by acute injection of both non-effective dose of AM 251, as well as AM 630. Among the all CB compounds used, only the combination of non-effective dose of oleamide (2.5 mg/kg) with non-effective dose of nicotine (0.5 mg/kg) caused an antidepressant effect. However, none of the CB receptor ligands, had influence on the antidepressant effects provoked by nicotine (0.2 mg/kg) injection. In turn, the combination of non-effective dose of oleamide (2.5 mg/kg); JWH (2 mg/kg) or AM 630 (2 mg/kg), but not of AM 251 (0.25 mg/kg), with non-effective dose of scopolamine (0.1 mg/kg), exhibited antidepressant properties. Indeed, all of the CB compounds used, intensified the antidepressant-like effects induced by an acute injection of scopolamine (0.3 mg/kg). Our results provide clear evidence that the endocannabinoid system participates in the depression-related behavior and through interactions with cholinergic system modulate these kind of responses. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Pharmacological evidence for the involvement of the NMDA receptor and nitric oxide pathway in the antidepressant-like effect of lamotrigine in the mouse forced swimming test.

    Science.gov (United States)

    Ostadhadi, Sattar; Ahangari, Mohammad; Nikoui, Vahid; Norouzi-Javidan, Abbas; Zolfaghari, Samira; Jazaeri, Farahnaz; Chamanara, Mohsen; Akbarian, Reyhaneh; Dehpour, Ahmad-Reza

    2016-08-01

    Lamotrigine is an anticonvulsant agent that shows clinical antidepressant properties. The aim of the present study was to investigate the involvement of N-methyl-d-aspartate (NMDA) receptors and nitric oxide-cyclic guanosine monophosphate (NO-cGMP) synthesis in possible antidepressant-like effect of lamotrigine in forced swimming test (FST) in mice. Intraperitoneal administration of lamotrigine (10mg/kg) decreased the immobility time in the FST (P<0.01) without any effect on locomotor activity in the open-field test (OFT), while higher dose of lamotrigine (30mg/kg) reduced the immobility time in the FST (P<0.001) as well as the number of crossings in the OFT. Pretreatment of animals with NMDA (75mg/kg), l-arginine (750mg/kg, a substrate for nitric oxide synthase [NOS]) or sildenafil (5mg/kg, a phosphodiesterase [PDE] 5 inhibitor) reversed the antidepressant-like effect of lamotrigine (10mg/kg) in the FST. Injection of l-nitroarginine methyl ester (l-NAME, 10mg/kg, a non-specific NOS inhibitor), 7-nitroindazole (30mg/kg, a neuronal NOS inhibitor), methylene blue (20mg/kg, an inhibitor of both NOS and soluble guanylate cyclase [sGC]), or MK-801 (0.05mg/kg), ketamine (1mg/kg), and magnesium sulfate (10mg/kg) as NMDA receptor antagonists in combination with a sub-effective dose of lamotrigine (5mg/kg) diminished the immobility time of animals in the FST compared with either drug alone. None of the drugs produced significant effects on the locomotor activity in the OFT. Based on our findings, it is suggested that the antidepressant-like effect of lamotrigine might mediated through inhibition of either NMDA receptors or NO-cGMP synthesis. Copyright © 2016. Published by Elsevier Masson SAS.

  17. Involvement of NMDA receptors and L-arginine/nitric oxide/cyclic guanosine monophosphate pathway in the antidepressant-like effects of topiramate in mice forced swimming test.

    Science.gov (United States)

    Ostadhadi, Sattar; Khan, Muhammad Imran; Norouzi-Javidan, Abbas; Chamanara, Mohsen; Jazaeri, Farahnaz; Zolfaghari, Samira; Dehpour, Ahmad-Reza

    2016-04-01

    Topiramate (TPM) is an agent primarily used in the treatment of epilepsy. Using mice model of forced swimming test (FST) the current study was basically aimed to investigate the influence of TPM on depression by inhibiting NMDA receptor and nitric oxide-cGMP production. When TPM was administered in a dose of 20 and 30 mg/kg by i.p. route it reduced the immobility time during FST. However this effect of TPM (30 mg/kg, i.p.) in the FST was abolished when the mice were pretreated either with NMDA (75 mg/kg, i.p.), or l-arginine (750 mg/kg, i.p. NO precursor), or sildenafil (5mg/kg, i.p. Phosphodiesterase 5 inhibitor). The immobility time in the FST was reduced after administration of L-NAME (10mg/kg, i.p, a non-specific NOS inhibitor), 7-nitoinidazol (30 mg/kg, i.p. a nNOS inhibitor) or MK-801 (0.05 mg/kg, i.p, a NMDA receptor antagonist) in combination with a subeffective dose of TPM (10mg/kg, i.p.) as compared with single use of either drug. Co-administrated of lower doses of MK-801 (0.01 mg/kg) or L-NAME (1mg/kg) failed to effect immobility time. However, simultaneous administration of these two agents in the same doses with subeffective dose of TPM (10mg/kg, i.p.), reduced the immobility time during FST. None of these drugs were found to have a profound effect on the locomotor activity per se during the open field test. Taken together, our data demonstrates that TPM exhibit antidepressant-like effect which is accomplished either due to inhibition of NMDA receptors or NO-cGMP production. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. NMDA-NO signaling in the dorsal and ventral hippocampus time-dependently modulates the behavioral responses to forced swimming stress.

    Science.gov (United States)

    Diniz, Cassiano R A F; Casarotto, Plínio C; Joca, Sâmia R L

    2016-07-01

    Hodological and genetic differences between dorsal (DH) and ventral (VH) hippocampus may convey distinct behavioral roles. DH is responsible for mediating cognitive process, such as learning and memory, while VH modulates neuroendocrine and emotional-motivational responses to stress. Manipulating glutamatergic NMDA receptors and nitric oxide (NO) systems of the hippocampus induces important changes in behavioral responses to stress. Nevertheless, there is no study concerning functional differences between DH and VH in the modulation of behavioral responses induced by stress models predictive of antidepressant effects. Thus, this study showed that reversible blockade of the DH or VH of animals submitted to the forced swimming test (FST), by using cobalt chloride (calcium-dependent synaptic neurotransmission blocker), was not able to change immobility time. Afterwards, the NMDA-NO system was evaluated in the FST by means of intra-DH or intra-VH administration of NMDA receptor antagonist (AP7), NOS1 and sGC inhibitors (N-PLA and ODQ, respectively). Bilateral intra-DH injections after pretest or before test were able to induce antidepressant-like effects in the FST. On the other hand, bilateral VH administration of AP-7, N-PLA and ODQ induced antidepressant-like effects only when injected before the test. Administration of NO scavenger (C-PTIO) intra-DH, after pretest and before test, or intra-VH before test induced similar results. Increased NOS1 levels was associated to stress exposure in the DH. These results suggest that the glutamatergic-NO system of the DH and VH are both able to modulate behavioral responses in the FST, albeit with differential participation along time after stress exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Involvement of nitric oxide-cyclic guanosine monophosphate pathway in the antidepressant-like effect of tropisetron and ondansetron in mice forced swimming test and tail suspension test.

    Science.gov (United States)

    Haj-Mirzaian, Arya; Kordjazy, Nastaran; Amiri, Shayan; Haj-Mirzaian, Arvin; Amini-Khoei, Hossien; Ostadhadi, Sattar; Dehpour, AhmadReza

    2016-06-05

    Antidepressant-like effects of 5-hydroxytryptamine subtype 3 (5-HT3) antagonists including tropisetron and ondansetron have been previously demonstrated in the literature. It was reported that stimulation of 5-HT3 receptors activate the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway, which is involved in regulation of behavioral and emotional functions. In our study, treating animals with tropisetron (5, 10, and 30mg/kg) and ondansetron (0.01 and 0.1µg/kg) significantly decreased the immobility time in forced swimming test (FST) and tail-suspension test (TST). Co-administration of subeffective doses of tropisetron (1mg/kg) and ondansetron (0.001µg/kg) with subeffective dose of l-NAME (10mg/kg, nonselective NO synthase (NOS) inhibitor) and 7-nitroindazole (25mg/kg, neural NOS inhibitor) exerted antidepressant-like effect in FST and TST, while aminoguanidine (50mg/kg, inducible NOS inhibitor) did not enhance the antidepressant-like effect of 5-HT3 antagonists. Besides, l-arginine (750mg/kg, NO precursor) and sildenafil (5mg/kg, phosphodiesterase inhibitor) suppressed the anti-immobility effect of 5-HT3 antagonists. None of the treatments altered the locomotor behavior of mice in open-field test. Also, hippocampal (but not cortical) nitrite level was significantly lower in tropisetron and ondansetron-treated mice compared with saline-injected mice. Also, co-administration of 7-nitroindazole with tropisetron or ondansetron caused a significant decrease in hippocampal nitrite levels. In conclusion, we suggest that antidepressant-like effect of tropisetron and ondansetron are partially mediated by modulation of NO-cGMP pathway. Copyright © 2016. Published by Elsevier B.V.

  20. m-Trifluoromethyl-diphenyl Diselenide Regulates Prefrontal Cortical MOR and KOR Protein Levels and Abolishes the Phenotype Induced by Repeated Forced Swim Stress in Mice.

    Science.gov (United States)

    Rosa, Suzan Gonçalves; Pesarico, Ana Paula; Martini, Franciele; Nogueira, Cristina Wayne

    2018-04-05

    The present study aimed to investigate the m-trifluoromethyl-diphenyl diselenide [(m-CF 3 -PhSe) 2 ] effects on prefrontal cortical MOR and KOR protein levels and phenotype induced by repeated forced swim stress (FSS) in mice. Adult Swiss mice were subjected to repeated FSS sessions, and after that, they performed the spontaneous locomotor/exploratory activity, tail suspension, and splash tests. (m-CF 3 -PhSe) 2 (0.1 to 5 mg/kg) was administered to mice 30 min before the first FSS session and 30 min before the subsequent repeated FSS. (m-CF 3 -PhSe) 2 abolished the phenotype induced by repeated FSS in mice. In addition, a single FSS session increased μ but reduced δ-opioid receptor contents, without changing the κ content. Mice subjected to repeated FSS had an increase in the μ content when compared to those of naïve group or subjected to single FSS. Repeated FSS induced an increase of δ-opioid receptor content compared to those mice subjected to single FSS. However, the δ-opioid receptor contents were lower than those found in the naïve group. The mice subjected to repeated FSS showed an increase in the κ-opioid receptor content when compared to that of the naïve mice. (m-CF 3 -PhSe) 2 regulated the protein contents of μ and κ receptors in mice subjected to repeated FSS. These findings demonstrate that (m-CF 3 -PhSe) 2 was effective to abolish the phenotype induced by FSS, which was accompanied by changes in the contents of cortical μ- and κ-opioid receptors.

  1. Forced swim stress increases ethanol consumption in C57BL/6J mice with a history of chronic intermittent ethanol exposure.

    Science.gov (United States)

    Anderson, Rachel I; Lopez, Marcelo F; Becker, Howard C

    2016-06-01

    Stress exposure has been identified as one risk factor for alcohol abuse that may facilitate the transition from social or regulated alcohol use to the development of alcohol dependence. Additionally, stress is a common trigger for relapse and subsequent loss of control of drinking in alcohol-dependent individuals. The present study was designed to characterize effects of repeated forced swim stress (FSS) on ethanol consumption in three rodent drinking models that engender high levels of ethanol consumption. Adult male C57BL/6J mice were exposed to 10-min FSS 4 h prior to each drinking session in three different models of high ethanol consumption: chronic intermittent ethanol (CIE) drinking (a model of dependence-like drinking), drinking-in-the-dark (DID; a model of binge-like drinking), and intermittent vs. continuous access (a model of escalated drinking). In the CIE drinking paradigm, daily FSS facilitated the escalation of ethanol intake that is typically seen in CIE-exposed mice without altering ethanol consumption in control mice exposed to FSS. FSS prior to drinking sessions did not alter ethanol consumption in the DID or intermittent access paradigms, whereas stressed mice in the continuous access procedure consumed less ethanol than their nonstressed counterparts. The CIE drinking paradigm may provide a helpful preclinical model of stress-induced transition to ethanol dependence that can be used to (1) identify underlying neural mechanisms that facilitate this transition and (2) evaluate the therapeutic potential of various pharmacological agents hypothesized to alleviate stress-induced drinking.

  2. Intermuscular interaction via myofascial force transmission: Effects of tibialis anterior and extensor digitorum longus length on force transmission from rat extensor digitorum longus muscle

    NARCIS (Netherlands)

    Maas, Huub; Baan, Guus C.; Huijing, P.A.J.B.M.

    2001-01-01

    Force transmission in rat anterior crural compartment, containing tibialis anterior (TA), extensor hallucis longus (EHL) and extensor digitorum longus (EDL) muscles, was investigated. These muscles together with the muscles of the peroneal compartment were excited maximally. Force was measured at

  3. PROPERTIES OF SWIMMING WATER

    Directory of Open Access Journals (Sweden)

    Tayfun KIR

    2004-10-01

    Full Text Available Swimming waters may be hazardous on human health. So, The physicians who work in the facilities, which include swimming areas, are responsible to prevent risks. To ensure hygiene of swimming water, European Swimming Water Directive offers microbiological, physical, and chemical criteria. [TAF Prev Med Bull 2004; 3(5.000: 103-104

  4. Swimming and feeding of mixotrophic biflagellates

    DEFF Research Database (Denmark)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed...... with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow...

  5. The effects of estrogens on learning in rats with chronic brain cholinergic deficiency in a Morris water test. Identification of the "passive swimming" component.

    Science.gov (United States)

    Mukhina, T V; Lermontova, N N; Van'kin, G I; Oettel, M; P'chev, V K; Bachurin, S O

    2004-03-01

    Chronic decreases in brain cholinergic functions due to intraventricular administration of the neurotoxin AF64A were accompanied by increases in the latent period of locating an invisible platform during training of rats in a Morris water test, as compared with control sham-operated animals. Recordings of the animals' movement trajectories using a video camera along with an original computer program (Behavioral Vision) showed that administration of 17beta-estradiol and its synthetic analog J-861 (0.2 mg/kg p.o. daily for seven days before and 10 days after single intraventricular injections of AF64A) improved learning. The directivity of platform search trajectories was assessed quantitatively using a new parameter--trajectory straightness. Introduction of the "passive swimming" parameter allowed periods of immobility in water to be identified within the total latent period in animals after administration of AF64A; 17beta-estradiol but not J-861 "eliminated" these periods. The new parameters (especially trajectory straightness) allowed the ability to learn to be discriminated from decreases in mobility, including mobility losses due to study agents, in the Morris water test.

  6. Antidepressant effect of pramipexole in mice forced swimming test: A cross talk between dopamine receptor and NMDA/nitric oxide/cGMP pathway.

    Science.gov (United States)

    Ostadhadi, Sattar; Imran Khan, Muhammad; Norouzi-Javidan, Abbas; Dehpour, Ahmad-Reza

    2016-07-01

    Pramipexole is a dopamine D2 receptor agonist indicated for treating Parkinson disorder. This study was aimed to investigate the effect of pramipexole in forced swimming test (FST) in mice and the possible involvement of activation of D2 receptors and inhibition of N-methyl-d-aspartate (NMDA) receptors and nitric oxide-cyclic guanosine monophosphate (NO-cGMP) on this effect. Intraperitoneal administration of pramipexole (1-3mg/kg) reduced the immobility time in the FST similar to fluoxetine (20mg/kg, i.p.). This effect of pramipexole (1mg/kg, i.p.) was ceased when mice were pretreated with haloperidol (0.15mg/kg, i.p,) and sulpiride (5mg/kg, i.p) as D2 receptor antagonists, NMDA (75mg/kg,i.p.), l-arginine (750mg/kg, i.p., a substrate for nitric oxide synthase) or sildenafil (5mg/kg, i.p., a phosphodiesterase 5 inhibitor). The administration of MK-801 (0.05mg/kg, i.p., a NMDA receptor antagonist) l-NG-Nitro arginine methyl ester (l-NAME, 10mg/kg, i.p., a non-specific nitric oxide synthase (NOS) inhibitor), 7-nitroindazole (30mg/kg, i.p., a neuronal NOS inhibitor) and methylene blue (10mg/kg, i.p.), an inhibitor of both NOS and soluble guanylyl cyclase (sGC) in combination with the sub-effective dose of pramipexole (0.3mg/kg, i.p.) reduced the immobility. Altogether, our data suggest that the antidepressant-like effect of pramipexole is dependent on the activation of D2 receptor and inhibition of either NMDA receptors and/or NO-cGMP synthesis. These results contribute to the understanding of the mechanisms underlying the antidepressant-like effect of pramipexole and reinforce the role of D2 receptors, NMDA receptors and l-arginine-NO-GMP pathway in the antidepressant mechanism of this agent. Copyright © 2016. Published by Elsevier Masson SAS.

  7. Antidepressant-like effect of atorvastatin in the forced swimming test in mice: the role of PPAR-gamma receptor and nitric oxide pathway.

    Science.gov (United States)

    Shahsavarian, Arash; Javadi, Shiva; Jahanabadi, Samane; Khoshnoodi, Mina; Shamsaee, Javad; Shafaroodi, Hamed; Mehr, Shahram Ejtemaei; Dehpour, Ahmadreza

    2014-12-15

    Atorvastatin is a synthetic and lipophilic statin which has been reported to have a positive role in reducing depression. The potential antidepressant-like effects of atorvastatin and the possible involvement of peroxisome proliferator-activated receptor gamma (PPAR_γ) and nitric oxide system were determined using forced swimming test (FST) in mice was studied. Atorvastatin (0.01, 0.1 and 1 mg/kg, p.o.) was administered 1 h before FST. To assess the involvement of PPAR_γ in the possible antidepressant effect of atorvastatin, pioglitazone, a PPAR_γ agonist (5 mg/kg), and GW-9662, a specific PPAR_γ antagonist (2 mg/kg), was co-administered with atorvastatin (0.01 mg/kg, p.o.) and then FST was performed. The possible role of nitric oxide pathway was determined by using co-administration of a non-specific NOS inhibitor, N-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg, i.p.), and a NO precursor, L-arginine (750 mg/kg, i.p.) with sub-effective doses of atorvastatin and pioglitazone. Immobility time was significantly decreased after atorvastatin administration (0.1 and 1 mg/kg, p.o.). Administration of pioglitazone or L-NAME in combination with the sub-effective dose of atorvastatin (0.01 mg/kg, p.o.) reduced the immobility time in the FST compared to drugs alone, showing the participation of these pathways; while co-administration of non-effective doses of atorvastatin and pioglitazone with GW9662 or L-arginine reversed antidepressant-like effect of atorvastatin in FST. Data from concurrent use of GW9662 and atorvastatin also demonstrated that the antidepressant effect of atorvastatin was significantly reversed by GW9662. The antidepressant-like effect of atorvastatin on mice in the FST is mediated at least in part through PPAR_γ receptors and NO pathway. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Attenuated stress response to acute restraint and forced swimming stress in arginine vasopressin 1b receptor subtype (Avpr1b) receptor knockout mice and wild-type mice treated with a novel Avpr1b receptor antagonist.

    Science.gov (United States)

    Roper, J A; Craighead, M; O'Carroll, A-M; Lolait, S J

    2010-11-01

    Arginine vasopressin (AVP) synthesised in the parvocellular region of the hypothalamic paraventricular nucleus and released into the pituitary portal vessels acts on the 1b receptor subtype (Avpr1b) present in anterior pituitary corticotrophs to modulate the release of adrenocorticotrophic hormone (ACTH). Corticotrophin-releasing hormone is considered the major drive behind ACTH release; however, its action is augmented synergistically by AVP. To determine the extent of vasopressinergic influence in the hypothalamic-pituitary-adrenal axis response to restraint and forced swimming stress, we compared the stress hormone levels [plasma ACTH in both stressors and corticosterone (CORT) in restraint stress only] following acute stress in mutant Avpr1b knockout (KO) mice compared to their wild-type controls following the administration of a novel Avpr1b antagonist. Restraint and forced swimming stress-induced increases in plasma ACTH were significantly diminished in mice lacking a functional Avpr1b and in wild-type mice that had been pre-treated with Avpr1b antagonist. A corresponding decrease in plasma CORT levels was also observed in acute restraint-stressed knockout male mice, and in Avpr1b-antagonist-treated male wild-type mice. By contrast, plasma CORT levels were not reduced in acutely restraint-stressed female knockout animals, or in female wild-type animals pre-treated with Avpr1b antagonist. These results demonstrate that pharmacological antagonism or inactivation of Avpr1b causes a reduction in the hypothalamic-pituitary-adrenal (HPA) axis response, particularly ACTH, to acute restraint and forced swimming stress, and show that Avpr1b knockout mice constitute a model by which to study the contribution of Avpr1b to the HPA axis response to acute stressors. © 2010 The Authors. Journal of Neuroendocrinology © 2010 Blackwell Publishing Ltd.

  9. Prey capture by freely swimming flagellates

    Science.gov (United States)

    Andersen, Anders; Dolger, Julia; Nielsen, Lasse Tor; Kiorboe, Thomas

    2017-11-01

    Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. Here, we explore the dependence of swimming kinematics and prey clearance rate on flagellar arrangement and determine optimal flagellar arrangements and essential trade-offs. To describe near-cell flows around freely swimming flagellates we consider a model in which the cell is represented by a no-slip sphere and each flagellum by a point force. For uniflagellates pulled by a single flagellum the model suggests that a long flagellum favors fast swimming, whereas high clearance rate is favored by a very short flagellum. For biflagellates with both a longitudinal and a transversal flagellum we explore the helical swimming kinematics and the prey capture sites. We compare our predictions with observations of swimming kinematics, prey capture, and flows around common marine flagellates. The Centre for Ocean Life is a VKR Centre of Excellence supported by the Villum Foundation.

  10. Distraction-like phenomena in maxillary bone due to application of orthodontic forces in ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Apostolos I Tsolakis

    2012-01-01

    Full Text Available Background: Orthodontic forces may not only influence the dentoalveolar system, but also the adjacent and surrounding cortical bone. Aim: Since there is very limited information on this issue, we aimed to study the possible changes in maxillary cortical bone following the application of heavy orthodontic forces in mature normal and osteoporotic rats. Materials and Methods: Twenty-four 6-month-old female rats were selected and divided into an ovariectomized group and a normal group. In both groups, the rats were subjected to a 60 grFNx01 orthodontic force on the upper right first molar for 14 days. Results: In both groups, histological sections showed that the application of this force caused hypertrophy and fatigue failure of the cortical maxillary bone. The osteogenic reaction to distraction is expressed by the formation of subperiosteal callus on the outer bony side, resembling that seen in distracted bones. Conclusion: From this study we concluded that heavy experimental orthodontic forces in rats affect the maxillary cortical bone. The osteogenic reaction to these forces, expressed histologically by subperiosteal callus formation, is similar to that seen in distraction osteogenesis models.

  11. SWIM EVERYDAY TO KEEP DEMENTIA AWAY

    Directory of Open Access Journals (Sweden)

    Nirmal Singh

    2005-03-01

    Full Text Available A sound mind resides in a sound body. Many individuals with an active lifestyle show sharp mental skills at an advanced age. Regular exercise has been shown to exert numerous beneficial effects on brawn as well as brain. The present study was undertaken to evaluate the influence of swimming on memory of rodents. A specially designed hexagonal water maze was used for the swimming exposures of animals. The learning and memory parameters were measured using exteroceptive behavioral models such as Elevated plus-maze, Hebb-Williams maze and Passive avoidance apparatus. The rodents (rats and mice were divided into twelve groups. The swimming exposure to the rodents was for 10- minute period during each session and there were two swimming exposures on each day. Rats and mice were subjected to swimming for -15 and -30 consecutive days. Control group animals were not subjected to swimming during above period. The learning index and memory score of all the animals was recorded on 1st, 2nd, 15th, 16th, 30th and 31st day employing above exteroceptive models. It was observed that rodents that underwent swimming regularly for 30- days showed sharp memories, when tested on above behavioral models whereas, control group animals showed decline in memory scores. Those animals, which underwent swimming for 15- days only showed good memory on 16th day, which however, declined after 30-days. These results emphasize the role of regular physical exercise particularly swimming in the maintenance and promotion of brain functions. The underlying physiological mechanism for improvement of memory appears to be the result of enhanced neurogenesis.

  12. Extramuscular myofascial force transmission within the rat anterior tibial compartment: Proximodistal differences in muscle force

    NARCIS (Netherlands)

    Huijing, P.A.J.B.M.; Baan, G.C.

    2001-01-01

    Intramuscular connective tissues are continuous to extramuscular connective tissues. If force is transmitted there, differences should be present between force at proximal and distal attachments of muscles. Extensor digitorum longus (EDL), tibialis anterior (TA), and extensor hallucis longus muscles

  13. Effects of diabetes on tooth movement and root resorption after orthodontic force application in rats.

    Science.gov (United States)

    Arita, K; Hotokezaka, H; Hashimoto, M; Nakano-Tajima, T; Kurohama, T; Kondo, T; Darendeliler, M A; Yoshida, N

    2016-05-01

    To investigate the effects of diabetes on orthodontic tooth movement and orthodontically induced root resorption in rats. Twenty-three 10-week-old male Sprague-Dawley rats divided into control (n = 7), diabetes (n = 9), and diabetes + insulin (n = 7) groups. Diabetes was induced by administering a single intraperitoneal injection of streptozotocin. Rats with a blood glucose level exceeding 250 mg/dl were assigned to the diabetes group. Insulin was administered daily to the diabetes + insulin group. A nickel-titanium closed-coil spring of 10 g was applied for 2 weeks to the maxillary left first molar in all rats to induce mesial tooth movement. Tooth movement was measured using microcomputed tomography images. To determine the quantity of root resorption, the mesial surfaces of the mesial and distal roots of the first molar were analyzed using both scanning electron microscopy and scanning laser microscopy. After 2 weeks, the amount of tooth movement in the diabetic rats was lower than that in the control rats. Root resorption was also significantly lower in the diabetic rats. These responses of the rats caused by diabetes were mostly diminished by insulin administration. Diabetes significantly reduced orthodontic tooth movement and orthodontically induced root resorption in rats. The regulation of blood glucose level through insulin administration largely reduced these abnormal responses to orthodontic force application. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Body dynamics and hydrodynamics of swimming larvae: a computational study

    NARCIS (Netherlands)

    Li, G.; Müller, U.K.; Leeuwen, van J.L.; Liu, H.

    2012-01-01

    To understand the mechanics of fish swimming, we need to know the forces exerted by the fluid and how these forces affect the motion of the fish. To this end, we developed a 3-D computational approach that integrates hydrodynamics and body dynamics. This study quantifies the flow around a swimming

  15. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  16. Swimming pool granuloma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

  17. Laryngoscopy during swimming

    DEFF Research Database (Denmark)

    Walsted, Emil S; Swanton, Laura L; van van Someren, Ken

    2017-01-01

    that precipitates their symptoms. This report provides the first description of the feasibility of performing continuous laryngoscopy during exercise in a swimming environment. The report describes the methodology and safety of the use of continuous laryngoscopy while swimming. Laryngoscope, 2017....

  18. Diarrhea and Swimming

    Science.gov (United States)

    ... 888) 232-6348 Contact CDC–INFO Healthy Swimming Health Benefits of Water-based Exercise Swimmer Protection Steps of ... Disinfection Microbial Testing & Disinfection Swimming Pool Chemicals Injuries & Outdoor Health International Recreational Water RWIs, Swimmer Hygiene, & Behavioral ...

  19. The hydrodynamics of swimming microorganisms

    International Nuclear Information System (INIS)

    Lauga, Eric; Powers, Thomas R

    2009-01-01

    Cell motility in viscous fluids is ubiquitous and affects many biological processes, including reproduction, infection and the marine life ecosystem. Here we review the biophysical and mechanical principles of locomotion at the small scales relevant to cell swimming, tens of micrometers and below. At this scale, inertia is unimportant and the Reynolds number is small. Our emphasis is on the simple physical picture and fundamental flow physics phenomena in this regime. We first give a brief overview of the mechanisms for swimming motility, and of the basic properties of flows at low Reynolds number, paying special attention to aspects most relevant for swimming such as resistance matrices for solid bodies, flow singularities and kinematic requirements for net translation. Then we review classical theoretical work on cell motility, in particular early calculations of swimming kinematics with prescribed stroke and the application of resistive force theory and slender-body theory to flagellar locomotion. After examining the physical means by which flagella are actuated, we outline areas of active research, including hydrodynamic interactions, biological locomotion in complex fluids, the design of small-scale artificial swimmers and the optimization of locomotion strategies.

  20. Protection of swimming-induced oxidative stress in some vital ...

    African Journals Online (AJOL)

    Protection of swimming-induced oxidative stress in some vital organs by the treatment of composite extract of Withania somnifera, Ocimum sanctum and Zingiber officinalis in male rat. D Misra, B Maiti, D Ghosh ...

  1. Hippocampal 3alpha,5alpha-THP may alter depressive behavior of pregnant and lactating rats.

    Science.gov (United States)

    Frye, Cheryl A; Walf, Alicia A

    2004-07-01

    The 5alpha-reduced metabolite of progesterone (P), 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP), may mediate progestins' effects to reduce depressive behavior of female rats in part through actions in the hippocampus. To investigate, forced swim test behavior and plasma and hippocampal progestin levels were assessed in groups of rats expected to differ in their 3alpha,5alpha-THP levels due to endogenous differences (pregnant and postpartum), administration of a 5alpha-reductase inhibitor (finasteride; 50 mg/kg sc), and/or gestational stress [prenatal stress (PNS)], an animal model of depression. Pregnant rats had higher plasma and hippocampal 3alpha,5alpha-THP levels and less depressive behavior (decreased immobility, increased struggling and swimming) in the forced swim test than did postpartum rats. Finasteride, compared to vehicle-administration, reduced plasma and hippocampal 3alpha,5alpha-THP levels and increased depressive behavior (increased immobility, decreased struggling and swimming). PNS was associated with lower hippocampal, but not plasma, 3alpha,5alpha-THP levels and increased swimming compared to that observed in control rats. Together, these data suggest that 3alpha,5alpha-THP in the hippocampus may mediate antidepressive behavior of female rats.

  2. Rigor force responses of permeabilized fibres from fast and slow skeletal muscles of aged rats.

    Science.gov (United States)

    Plant, D R; Lynch, G S

    2001-09-01

    1. Ageing is generally associated with a decline in skeletal muscle mass and strength and a slowing of muscle contraction, factors that impact upon the quality of life for the elderly. The mechanisms underlying this age-related muscle weakness have not been fully resolved. The purpose of the present study was to determine whether the decrease in muscle force as a consequence of age could be attributed partly to a decrease in the number of cross-bridges participating during contraction. 2. Given that the rigor force is proportional to the approximate total number of interacting sites between the actin and myosin filaments, we tested the null hypothesis that the rigor force of permeabilized muscle fibres from young and old rats would not be different. 3. Permeabilized fibres from the extensor digitorum longus (fast-twitch; EDL) and soleus (predominantly slow-twitch) muscles of young (6 months of age) and old (27 months of age) male F344 rats were activated in Ca2+-buffered solutions to determine force-pCa characteristics (where pCa = -log(10)[Ca2+]) and then in solutions lacking ATP and Ca2+ to determine rigor force levels. 4. The rigor forces for EDL and soleus muscle fibres were not different between young and old rats, indicating that the approximate total number of cross-bridges that can be formed between filaments did not decline with age. We conclude that the age-related decrease in force output is more likely attributed to a decrease in the force per cross-bridge and/or decreases in the efficiency of excitation-contraction coupling.

  3. Swimming of Paramecium in confined channels

    Science.gov (United States)

    Jung, Sunghwan

    2012-02-01

    Many living organisms in nature have developed a few different swimming modes, presumably derived from hydrodynamic advantage. Paramecium is a ciliated protozoan covered by thousands of cilia with a few nanometers in diameter and tens of micro-meters in length and is able to exhibit both ballistic and meandering motions. First, we characterize ballistic swimming behaviors of ciliated microorganisms in glass capillaries of different diameters and explain the trajectories they trace out. We develop a theoretical model of an undulating sheet with a pressure gradient and discuss how it affects the swimming speed. Secondly, investigation into meandering swimmings within rectangular PDMS channels of dimension smaller than Paramecium length. We find that Paramecium executes a body-bend (an elastic buckling) using the cilia while it meanders. By considering an elastic beam model, we estimate and show the universal profile of forces it exerts on the walls. Finally, we discuss a few other locomotion of Paramecium in other extreme environments like gel.

  4. The effects of swimming pattern on the energy use of gilthead seabream (Sparus aurata L.)

    DEFF Research Database (Denmark)

    Steinhausen, Maria Faldborg; Steffensen, John Fleng; Andersen, Niels Gerner

    2010-01-01

    Oxygen consumption ( ) was measured for gilthead seabream (Sparus aurata) during spontaneous and forced activities. During spontaneous activity, the swimming pattern was analysed for the effect on   on the average speed (U), turning rate (¿) and change in speed (¿U). All swimming characteristics...... and   during forced activity was also established. During spontaneous activity, 2.5 times more energy was used than in forced swimming at a speed of 0.5 BL s-1. This indicates that spontaneous swimming costs may be considerably higher compared with those of a fixed swimming speed. However, comparing...... contributed significantly to the source of spontaneous swimming costs, and the models explained up to 58% of the variation in   Prediction of   of fish in field studies can thereby be improved if changes in speed and direction are determined in addition to swimming speed. A relationship between swimming speed...

  5. A Correlational Analysis of Tethered Swimming, Swim Sprint Performance and Dry-land Power Assessments.

    Science.gov (United States)

    Loturco, I; Barbosa, A C; Nocentini, R K; Pereira, L A; Kobal, R; Kitamura, K; Abad, C C C; Figueiredo, P; Nakamura, F Y

    2016-03-01

    Swimmers are often tested on both dry-land and in swimming exercises. The aim of this study was to test the relationships between dry-land, tethered force-time curve parameters and swimming performances in distances up to 200 m. 10 young male high-level swimmers were assessed using the maximal isometric bench-press and quarter-squat, mean propulsive power in jump-squat, squat and countermovement jumps (dry-land assessments), peak force, average force, rate of force development (RFD) and impulse (tethered swimming) and swimming times. Pearson product-moment correlations were calculated among the variables. Peak force and average force were very largely correlated with the 50- and 100-m swimming performances (r=- 0.82 and -0.74, respectively). Average force was very-largely/largely correlated with the 50- and 100-m performances (r=- 0.85 and -0.67, respectively). RFD and impulse were very-largely correlated with the 50-m time (r=- 0.72 and -0.76, respectively). Tethered swimming parameters were largely correlated (r=0.65 to 0.72) with mean propulsive power in jump-squat, squat-jump and countermovement jumps. Finally, mean propulsive power in jump-squat was largely correlated (r=- 0.70) with 50-m performance. Due to the significant correlations between dry-land assessments and tethered/actual swimming, coaches are encouraged to implement strategies able to increase leg power in sprint swimmers. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  7. Orthodontically induced osteocyte apoptosis under different force magnitudes in rats: an immunohistochemical study.

    Science.gov (United States)

    Kassem, Hassan E; Talaat, Iman M; El-Sawa, Afaf; Ismail, Hanan; Zaher, Abbas

    2017-10-01

    We investigated the effect of different force magnitudes on osteocyte apoptosis in a model of orthodontic tooth movement. Forty-nine male Sprague Dawley rats (7-9 wk of age) were divided into light- and heavy-force groups (n = 21 each group) and a control group (n = 7). A coil spring delivered pressure (either 10-15 g or 20-25 g) to the left maxillary first molar. The rats were sacrificed 1, 3, or 5 d after placement of the appliance. Sections of the maxillary first molars were immunostained for caspase-3. Upon force application, the number of apoptotic osteocytes significantly increased in the pressure side at 1 d and remained the same at 3 d and 5 d. However, there was no significant difference in the number of apoptotic osteocytes between the two force groups. We conclude that osteocyte apoptosis appears to increase under orthodontic loading, reaching a plateau after 1 d. However, osteocyte apoptosis seems to be independent of the magnitude of orthodontic forces tested. © 2017 Eur J Oral Sci.

  8. Continuous Force Decoding from Local Field Potentials of the Primary Motor Cortex in Freely Moving Rats.

    Science.gov (United States)

    Khorasani, Abed; Heydari Beni, Nargess; Shalchyan, Vahid; Daliri, Mohammad Reza

    2016-10-21

    Local field potential (LFP) signals recorded by intracortical microelectrodes implanted in primary motor cortex can be used as a high informative input for decoding of motor functions. Recent studies show that different kinematic parameters such as position and velocity can be inferred from multiple LFP signals as precisely as spiking activities, however, continuous decoding of the force magnitude from the LFP signals in freely moving animals has remained an open problem. Here, we trained three rats to press a force sensor for getting a drop of water as a reward. A 16-channel micro-wire array was implanted in the primary motor cortex of each trained rat, and obtained LFP signals were used for decoding of the continuous values recorded by the force sensor. Average coefficient of correlation and the coefficient of determination between decoded and actual force signals were r = 0.66 and R 2  = 0.42, respectively. We found that LFP signal on gamma frequency bands (30-120 Hz) had the most contribution in the trained decoding model. This study suggests the feasibility of using low number of LFP channels for the continuous force decoding in freely moving animals resembling BMI systems in real life applications.

  9. The effect of microinjection of dimethyl sulfoxide into the rostral ventromedial medulla on swim stress-induced analgesia

    Directory of Open Access Journals (Sweden)

    S. Nazemi

    2018-02-01

    Full Text Available Background: Dimethyl sulfoxide (DMSO is an important solvent for compounds that used in pain research. Rostral ventromedial medulla (RVM plays an important role in modulating nociception and stress-induced analgesia (SIA. Objective: The aim of this study was to investigate the effect of DMSO administration into the RVM on SIA by using formalin test. Methods: This experimental study was conducted on 27 Wistar male rats (200±30 gr were randomly assigned to control, stress and stress+DMSO groups. Animals were placed in a water reservoir (20±1°C for 3 minutes to induce forced swimming stress. Stereotaxic surgery was performed to microinjection of DMSO (0.5μl, 100% into RVM. The pain behavior score was evaluated by subcutaneous injection of formalin 2% in the dorsal plantar region of hid paw. Findings: The pain score of phase 1, interphase and phase 2 of formalin test in swim stress group decreased significantly in comparison to control group (P<0.001, P< 0.05, P<0.001 respectively. In addition, the pain score of three phase of formalin test after DMSO injection in swim stress group decreased significantly in comparison to control and stress group (P<0.001, P<0.05 respectively. Conclusion: Also microinjections of DMSO into the RVM potentiate the swim stress analgesia. According to the analgesic effects of dimethyl sulfoxide, as well as its ability to potentiate stressinduced analgesia, DMSO should be used with caution as a solvent in pain studies. Conclusion: Force swim stress induces analgesia in, and microinjections of DMSO into the RVM potentiate the swim stress analgesia. According to the analgesic effects of DMSO, as well as its ability to potentiate stress-induced analgesia, it should be used with caution as solvent in pain studies.

  10. Swim stress exaggerates the hyperactive mesocortical dopamine system in a rodent model of autism.

    Science.gov (United States)

    Nakasato, Akane; Nakatani, Yasushi; Seki, Yoshinari; Tsujino, Naohisa; Umino, Masahiro; Arita, Hideho

    2008-02-08

    Several clinical reports have suggested that there is a hyperactivation of the dopaminergic system in people with autism. Using rats exposed prenatally to valproic acid (VPA) as an animal model of autism, we measured dopamine (DA) levels in samples collected from the frontal cortex (FC) using in vivo microdialysis and HPLC. The basal DA level in FC was significantly higher in VPA-exposed rats relative to controls. Since the mesocortical DA system is known to be sensitive to physical and psychological stressors, we measured DA levels in FC before, during, and after a 60-min forced swim test (FST). There were further gradual increases in FC DA levels during the FST in the VPA-exposed rats, but not in the control rats. Behavioral analysis during the last 10 min of the FST revealed a significant decrease in active, escape-oriented behavior and an increase in immobility, which is thought to reflect the development of depressive behavior that disengages the animal from active forms of coping with stressful stimuli. These results suggest that this rodent model of autism exhibits a hyperactive mesocortical DA system, which is exaggerated by swim stress. This abnormality may be responsible for depressive and withdrawal behavior observed in autism.

  11. Propulsive efficiency of frog swimming with different feet and swimming patterns

    Directory of Open Access Journals (Sweden)

    Fan Jizhuang

    2017-04-01

    Full Text Available Aquatic and terrestrial animals have different swimming performances and mechanical efficiencies based on their different swimming methods. To explore propulsion in swimming frogs, this study calculated mechanical efficiencies based on data describing aquatic and terrestrial webbed-foot shapes and swimming patterns. First, a simplified frog model and dynamic equation were established, and hydrodynamic forces on the foot were computed according to computational fluid dynamic calculations. Then, a two-link mechanism was used to stand in for the diverse and complicated hind legs found in different frog species, in order to simplify the input work calculation. Joint torques were derived based on the virtual work principle to compute the efficiency of foot propulsion. Finally, two feet and swimming patterns were combined to compute propulsive efficiency. The aquatic frog demonstrated a propulsive efficiency (43.11% between those of drag-based and lift-based propulsions, while the terrestrial frog efficiency (29.58% fell within the range of drag-based propulsion. The results illustrate the main factor of swimming patterns for swimming performance and efficiency.

  12. Is paramecium swimming autonomic?

    Science.gov (United States)

    Bandyopadhyay, Promode R.; Toplosky, Norman; Hansen, Joshua

    2010-11-01

    We seek to explore if the swimming of paramecium has an underlying autonomic mechanism. Such robotic elements may be useful in capturing the disturbance field in an environment in real time. Experimental evidence is emerging that motion control neurons of other animals may be present in paramecium as well. The limit cycle determined using analog simulation of the coupled nonlinear oscillators of olivo-cerebellar dynamics (ieee joe 33, 563-578, 2008) agrees with the tracks of the cilium of a biological paramecium. A 4-motor apparatus has been built that reproduces the kinematics of the cilium motion. The motion of the biological cilium has been analyzed and compared with the results of the finite element modeling of forces on a cilium. The modeling equates applied torque at the base of the cilium with drag, the cilium stiffness being phase dependent. A low friction pendulum apparatus with a multiplicity of electromagnetic actuators is being built for verifying the maps of the attractor basin computed using the olivo-cerebellar dynamics for different initial conditions. Sponsored by ONR 33.

  13. Comparación de los efectos del D-004, imipramina y sertralina en el modelo de nado forzado en ratones Comparative effects of D-004, Imipramine and Sertraline in the forced swimming test in mice

    Directory of Open Access Journals (Sweden)

    Daisy Carbajal Quintana

    2012-09-01

    fruit (Roystonea regia that is effective to prevent prostatic hyperplasia by inhibiting 5 a-reductase and shows moderate antidepressant effects in the forced swimming test (FST and tail suspension test. Objective: to compare the effects of D-004, Imipramine and Sertraline on the duration of behaviours under conditions of immobility, swimming and climbing in the forced swimming test. Methods: mice were randomly distributed in 8 groups: control (vehicle, 3 treated with D-004 (100, 250 and 500 mg/kg, 2 with Sertraline and 2 with Imipramine (30 and 50 mg/kg respectively. Mice were placed in a glass cylinder containing 6 cm high column of water and their behaviours were quantified. Results: oral administration of D-004 (100, 250 and 500 mg/kg during 14 days reduced the length of time of immobility with respect to the control group (17, 22 and 25 %, and significantly increased the behaviours at swimming by 1.58, 1.68 and 1.74 times. This is a moderate effect (25 % if compared with Sertraline and Imipramine (³ 60 % The doses of 250 and 500 mg/kg showed that climbing behaviours were 2.79 and 3.55 times higher than the control group. The results were similar to those of Imipramine but less effective. Conclusions: D-004 showed moderate antidepressant effect. This fact could help in the treatment of patients with benign prostatic hyperplasia, who reported similar depressive status.

  14. Experimental hydrodynamics of swimming in fishes

    Science.gov (United States)

    Tytell, Eric Daniel

    2005-11-01

    The great diversity of fish body shapes suggests that they have adapted to different selective pressures. For many fishes, the pressures include hydrodynamic demands: swimming efficiently or accelerating rapidly, for instance. However, the hydrodynamic advantages or disadvantages to specific morphologies are poorly understood. In particular, eels have been considered inefficient swimmers, but they migrate long distances without feeding, a task that requires efficient swimming. This dissertation, therefore, begins with an examination of the swimming hydrodynamics of American eels, Anguilla rostrata, at steady swimming speeds from 0.5 to 2 body lengths (L) per second and during accelerations from -1.4 to 1.3 L s -2. The final chapter examines the hydrodynamic effects of body shape directly by describing three-dimensional flow around swimming bluegill sunfish, Lepomis macrochirus. In all chapters, flow is quantified using digital particle image velocimetry, and simultaneous kinematics are measured from high-resolution digital video. The wake behind a swimming eel in the horizontal midline plane is described first. Rather than producing a wake with fluid jets angled backwards, like in fishes such as sunfish, eels have a wake with exclusively lateral jets. The lack of downstream momentum indicates that eels balance the axial forces of thrust and drag evenly over time and over their bodies, and therefore do not change axial fluid momentum. This even balance, present at all steady swimming speeds, is probably due to the relatively uniform body shape of eels. As eels accelerate, thrust exceeds drag, axial momentum increases, and the wake approaches that of other fishes. During steady swimming, though, the lack of axial momentum prevents direct efficiency estimation. The effect of body shape was examined directly by measuring flow in multiple transverse planes along the body of bluegill sunfish swimming at 1.2 L s-1. The dorsal and anal fin, neglected in many previous

  15. Sex differences associated with intermittent swim stress.

    Science.gov (United States)

    Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

    2013-11-01

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

  16. THE STUDY OF VITAMINS B1, B6, AND B12 EFFECTS ON ADRENAL CORTEX ADAPTATION BY MONITORING SOME ENZYME SYSTEMS IN RATS TRAINED BY SWIMMING

    Directory of Open Access Journals (Sweden)

    Dragana Veličković

    2014-06-01

    Full Text Available The adrenal hormones play a central role in response to environmental stimuli, both internal and external. We analyzed enzymes activities (LDH- lactate dehydrogenase, GLDHglutamate dehydrogenase and AcPh – acid phosphatase in adrenal cortex through swimming exercises and under the influence of B-group vitamins. The analyzed cases in the experiment revealed significant increase of enzyme activities, namely in the zona fasciculata and zona reticularis of the adrenal cortex. Physical exertion is a form of stress and causes steroidogenesis process expression. The vitamins used take part as co-ferments in production of a lot of enzymes and in their activities as well. Improvement of the enzyme system in adrenal glands in animals through swimming training with addition of vitamins B1, B6 and B12 leads to faster and long-term production of hormones necessary for stress response known as General Adaptation Syndrome

  17. Validity Assessment of 5 Day Repeated Forced-Swim Stress to Model Human Depression in Young-Adult C57BL/6J and BALB/cJ Mice.

    Science.gov (United States)

    Mul, Joram D; Zheng, Jia; Goodyear, Laurie J

    2016-01-01

    The development of animal models with construct, face, and predictive validity to accurately model human depression has been a major challenge. One proposed rodent model is the 5 d repeated forced swim stress (5d-RFSS) paradigm, which progressively increases floating during individual swim sessions. The onset and persistence of this floating behavior has been anthropomorphically characterized as a measure of depression. This interpretation has been under debate because a progressive increase in floating over time may reflect an adaptive learned behavioral response promoting survival, and not depression (Molendijk and de Kloet, 2015). To assess construct and face validity, we applied 5d-RFSS to C57BL/6J and BALB/cJ mice, two mouse strains commonly used in neuropsychiatric research, and measured a combination of emotional, homeostatic, and psychomotor symptoms indicative of a depressive-like state. We also compared the efficacy of 5d-RFSS and chronic social defeat stress (CSDS), a validated depression model, to induce a depressive-like state in C57BL/6J mice. In both strains, 5d-RFSS progressively increased floating behavior that persisted for at least 4 weeks. 5d-RFSS did not alter sucrose preference, body weight, appetite, locomotor activity, anxiety-like behavior, or immobility behavior during a tail-suspension test compared with nonstressed controls. In contrast, CSDS altered several of these parameters, suggesting a depressive-like state. Finally, predictive validity was assessed using voluntary wheel running (VWR), a known antidepressant intervention. Four weeks of VWR after 5d-RFSS normalized floating behavior toward nonstressed levels. These observations suggest that 5d-RFSS has no construct or face validity but might have predictive validity to model human depression.

  18. Corticospinal signals recorded with MEAs can predict the volitional forearm forces in rats.

    Science.gov (United States)

    Guo, Yi; Mesut, Sahin; Foulds, Richard A; Adamovich, Sergei V

    2013-01-01

    We set out to investigate if volitional components in the descending tracts of the spinal cord white matter can be accessed with multi-electrode array (MEA) recording technique. Rats were trained to press a lever connected to a haptic device with force feedback to receive sugar pellets. A flexible-substrate multi-electrode array was chronically implanted into the dorsal column of the cervical spinal cord. Field potentials and multi-unit activities were recorded from the descending axons of the corticospinal tract while the rat performed a lever pressing task. Forelimb forces, recorded with the sensor attached to the lever, were reconstructed using the hand position data and the neural signals through multiple trials over three weeks. The regression coefficients found from the trial set were cross-validated on the other trials recorded on same day. Approximately 30 trials of at least 2 seconds were required for accurate model estimation. The maximum correlation coefficient between the actual and predicted force was 0.7 in the test set. Positional information and its interaction with neural signals improved the correlation coefficient by 0.1 to 0.15. These results suggest that the volitional information contained in the corticospinal tract can be extracted with multi-channel neural recordings made with parenchymal electrodes.

  19. Scaling the Thrust Production and Energetics of Inviscid Intermittent Swimming

    Science.gov (United States)

    Akoz, Emre; Moored, Keith

    2015-11-01

    Many fish have adopted an intermittent swimming gait sometimes referred as a burst-and-coast behavior. By using this gait, fish have been estimated at reducing their energetic cost of swimming by about 50%. Lighthill proposed that the skin friction drag of an undulating body can be around 400% greater than a rigidly-held coasting body, which may explain the energetic savings of intermittent swimming. Recent studies have confirmed the increase in skin friction drag over an undulating body, however, the increase is on the order of 20-70%. This more modest gain in skin friction drag is not sufficient to lead to the observed energy savings. Motivated by these observations, we investigate the inviscid mechanisms behind intermittent swimming for parameters typical of biology. We see that there is an energy savings at a fixed swimming speed for intermittent swimming as compared to continuous swimming. Then we consider three questions: What is the nature of the inviscid mechanism that leads to the observed energy savings, how do the forces and energetics of intermittent swimming scale with the swimming parameters, and what are the limitations to the benefit? Supported by the Office of Naval Research under Program Director Dr. Bob Brizzola, MURI grant number N00014-14-1-0533.

  20. Sex differences in the reinstatement of methamphetamine seeking after forced abstinence in Sprague-Dawley rats

    Directory of Open Access Journals (Sweden)

    Jana eKucerova

    2015-07-01

    Full Text Available Preventing relapse to drug abuse is one of the struggles faced by clinicians in order to treat patients with substance use disorders (DSM-5. There is a large body of clinical evidence suggesting differential characteristics of the disorder in men and women which is in line with preclinical findings as well. The aim of this study was to assess differences in relapse-like behavior in methamphetamine (METH seeking after a period of forced abstinence which simulates the real clinical situation very well. Findings from such study might add new insights in gender differences in relapse mechanisms to previous studies, which employ a classical drug or cue-induced reinstatement procedure following the extinction training.Adult male and female Sprague-Dawley rats were used in IV self-administration procedure conducted in operant boxes using nose-poke operandi (Coulborn Instruments, USA. Active nose-poke resulted in activation of the infusion pump to deliver one intravenous infusion of METH (0.08 mg/kg. After baseline drug intake was established (maintenance phase, a period of forced abstinence was initiated and rats were kept singly in their home-cages for 14 days. Finally, one reinstatement session in operant boxes was conducted. Females were found to self-administer significantly lower dose of METH. The relapse rate was assessed as a number of active nose-pokes during the reinstatement session, expressed as a percentage of active nose-poking during the maintenance phase. Females displayed approximately 300 % of active nose-pokes compared to 48 % in males. This indicates higher vulnerability to relapse of METH seeking behavior in female rats. This effect was detected in all females, independently of current phase of their estrous cycle. Therefore, this paradigm using operant drug self-administration and reinstatement of drug-seeking after forced abstinence model can be used for preclinical screening for potential new anti-relapse medications specific for

  1. Swimming Pool Safety

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

  2. Swimming pool special; Zwembadspecial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

  3. Quiet swimming at low Reynolds number

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Wadhwa, Navish; Kiørboe, Thomas

    2015-01-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that elim......The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode...... that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three......-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws...

  4. Orthodontic Forces Induce the Cytoprotective Enzyme Heme Oxygenase-1 in Rats

    Science.gov (United States)

    Suttorp, Christiaan M.; Xie, Rui; Lundvig, Ditte M. S.; Kuijpers-Jagtman, Anne Marie; Uijttenboogaart, Jasper Tom; Van Rheden, René; Maltha, Jaap C.; Wagener, Frank A. D. T. G.

    2016-01-01

    Orthodontic forces disturb the microenvironment of the periodontal ligament (PDL), and induce craniofacial bone remodeling which is necessary for tooth movement. Unfortunately, orthodontic tooth movement is often hampered by ischemic injury and cell death within the PDL (hyalinization) and root resorption. Large inter-individual differences in hyalinization and root resorption have been observed, and may be explained by differential protection against hyalinization. Heme oxygenase-1 (HO-1) forms an important protective mechanism by breaking down heme into the strong anti-oxidants biliverdin/bilirubin and the signaling molecule carbon monoxide. These versatile HO-1 products protect against ischemic and inflammatory injury. We postulate that orthodontic forces induce HO-1 expression in the PDL during experimental tooth movement. Twenty-five 6-week-old male Wistar rats were used in this study. The upper three molars at one side were moved mesially using a Nickel-Titanium coil spring, providing a continuous orthodontic force of 10 cN. The contralateral side served as control. After 6, 12, 72, 96, and 120 h groups of rats were killed. On parasagittal sections immunohistochemical staining was performed for analysis of HO-1 expression and quantification of osteoclasts. Orthodontic force induced a significant time-dependent HO-1 expression in mononuclear cells within the PDL at both the apposition- and resorption side. Shortly after placement of the orthodontic appliance HO-1 expression was highly induced in PDL cells but dropped to control levels within 72 h. Some osteoclasts were also HO-1 positive but this induction was shown to be independent of time- and mechanical stress. It is tempting to speculate that differential induction of tissue protecting- and osteoclast activating genes in the PDL determine the level of bone resorption and hyalinization and, subsequently, “fast” and “slow” tooth movers during orthodontic treatment. PMID:27486402

  5. Orthodontic Forces Induce the Cytoprotective Enzyme Heme Oxygenase-1 in Rats.

    Science.gov (United States)

    Suttorp, Christiaan M; Xie, Rui; Lundvig, Ditte M S; Kuijpers-Jagtman, Anne Marie; Uijttenboogaart, Jasper Tom; Van Rheden, René; Maltha, Jaap C; Wagener, Frank A D T G

    2016-01-01

    Orthodontic forces disturb the microenvironment of the periodontal ligament (PDL), and induce craniofacial bone remodeling which is necessary for tooth movement. Unfortunately, orthodontic tooth movement is often hampered by ischemic injury and cell death within the PDL (hyalinization) and root resorption. Large inter-individual differences in hyalinization and root resorption have been observed, and may be explained by differential protection against hyalinization. Heme oxygenase-1 (HO-1) forms an important protective mechanism by breaking down heme into the strong anti-oxidants biliverdin/bilirubin and the signaling molecule carbon monoxide. These versatile HO-1 products protect against ischemic and inflammatory injury. We postulate that orthodontic forces induce HO-1 expression in the PDL during experimental tooth movement. Twenty-five 6-week-old male Wistar rats were used in this study. The upper three molars at one side were moved mesially using a Nickel-Titanium coil spring, providing a continuous orthodontic force of 10 cN. The contralateral side served as control. After 6, 12, 72, 96, and 120 h groups of rats were killed. On parasagittal sections immunohistochemical staining was performed for analysis of HO-1 expression and quantification of osteoclasts. Orthodontic force induced a significant time-dependent HO-1 expression in mononuclear cells within the PDL at both the apposition- and resorption side. Shortly after placement of the orthodontic appliance HO-1 expression was highly induced in PDL cells but dropped to control levels within 72 h. Some osteoclasts were also HO-1 positive but this induction was shown to be independent of time- and mechanical stress. It is tempting to speculate that differential induction of tissue protecting- and osteoclast activating genes in the PDL determine the level of bone resorption and hyalinization and, subsequently, "fast" and "slow" tooth movers during orthodontic treatment.

  6. Simulation of swimming strings immersed in a viscous fluid flow

    Science.gov (United States)

    Huang, Wei-Xi; Sung, Hyung Jin

    2006-11-01

    In nature, many phenomena involve interactions between flexible bodies and their surrounding viscous fluid, such as a swimming fish or a flapping flag. The intrinsic dynamics is complicate and not well understood. A flexible string can be regarded as a one-dimensional flag model. Many similarities can be found between the flapping string and swimming fish, although different wake speed results in a drag force for the flapping string and a propulsion force for the swimming fish. In the present study, we propose a mathematical formulation for swimming strings immersed in a viscous fluid flow. Fluid motion is governed by the Navier-Stokes equations and a momentum forcing is added in order to bring the fluid to move at the same velocity with the immersed surface. A flexible inextensible string model is described by another set of equations with an additional momentum forcing which is a result of the fluid viscosity and the pressure difference across the string. The momentum forcing is calculated by a feedback loop. Simulations of several numerical examples are carried out, including a hanging string which starts moving under gravity without ambient fluid, a swinging string immersed in a quiescent viscous fluid, a string swimming within a uniform surrounding flow, and flow over two side-by-side strings. The numerical results agree well with the theoretical analysis and previous experimental observations. Further simulation of a swimming fish is under consideration.

  7. Biomechanical Analysis of the Swim-Start: A Review

    Directory of Open Access Journals (Sweden)

    Julien Vantorre, Didier Chollet, Ludovic Seifert

    2014-06-01

    Full Text Available This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water entry, require adaptations to the swimmer’s chosen technique over the course of a performance; we thus define the swim-start as the moment when preparation for take-off begins to the moment when the swimming pattern begins. A secondary objective is to determine the role of adaptive variability as it emerges during the swim-start. Variability is contextualized as having a functional role and operating across multiple levels of analysis: inter-subject (expert versus non-expert, inter-trial or intra-subject (through repetitions of the same movement, and inter-preference (preferred versus non-preferred technique. Regarding skill effects, we assume that swim-start expertise is distinct from swim stroke expertise. Highly skilled swim-starts are distinguished in terms of several factors: reaction time from the start signal to the impulse on the block, including the control and regulation of foot force and foot orientation during take-off; appropriate amount of glide time before leg kicking commences; effective transition from leg kicking to break-out of full swimming with arm stroking; overall maximal leg and arm propulsion and minimal water resistance; and minimized energy expenditure through streamlined body position. Swimmers who are less expert at the swim-start spend more time in this phase and would benefit from training designed to reduce: (i the time between reaction to the start signal and impulse on the block, and (ii the time in transition (i

  8. Effects of different delayed exercise regimens on cognitive performance in fimbria‑fornix transected rats

    DEFF Research Database (Denmark)

    Wogensen, Elise; Marschner, Linda; Gram, Marie Gajhede

    2017-01-01

    Studies have shown that exercise can positively influence cognitive performance after brain injury. This study investigated the effects of different exercise regimens on allocentric place learning after fimbria‑fornix (FF) transection. One hundred and sixteen pre‑shaped rats were subjected either...... to a mechanical transection of the FF or control sham surgery and divided into following groups: i) no exercise (NE), ii) voluntary exercise in a running wheel (RW), iii) forced swimming exercise administered as interval training of short (3x5 min) duration (FS‑SI), iv) forced swimming exercise administered...

  9. Orthodontic forces induce the cytoprotective enzyme heme oxygenase-1 in rats

    Directory of Open Access Journals (Sweden)

    Christiaan M. Suttorp

    2016-07-01

    Full Text Available Orthodontic forces disturb the microenvironment of the periodontal ligament (PDL, and induce craniofacial bone remodeling which is necessary for tooth movement. Unfortunately, orthodontic tooth movement is often hampered by ischemic injury and cell death within the PDL (hyalinization and root resorption. Large inter-individual differences in hyalinization and root resorption have been observed, and may be explained by differential protection against hyalization. Heme oxygenase-1 (HO-1 forms an important protective mechanism by breaking down heme into the strong anti-oxidants biliverdin/bilirubin and the signaling molecule carbon monoxide. These versatile HO-products protect against ischemic and inflammatory injury. We postulate that orthodontic forces induce HO-1 expression in the PDL during experimental tooth movement. Twenty-five 6-week-old male Wistar rats were used in this study. The upper three molars at one side were moved mesially using a Ni-Ti 10 cN coil spring. The contralateral side served as control. After 6, 12, 72, 96 and 120 hrs rats were killed. On parasagittal sections immunohistochemical staining was performed for analysis of HO-1 expression and quantification of multinuclear osteoclasts. Orthodontic force induced a significant time-dependent HO-1 expression in the mononuclear cell population within the PDL at both the apposition- and resorption side. Shortly after appliance placement HO-1 expression was highly induced in PDL cells but dropped to control levels within 72 hours. Some osteoclasts were HO-1 positive but this induction was shown to be independent of time- and mechanical stress. It is tempting to speculate that differential induction of cytoprotective enzymes as HO-1 in the PDL determines the level of hyalinization and, subsequently, fast and slow tooth movers during orthodontic treatment.

  10. TUNING IN TO FISH SWIMMING WAVES - BODY FORM, SWIMMING MODE AND MUSCLE FUNCTION

    NARCIS (Netherlands)

    WARDLE, CS; VIDELER, JJ; ALTRINGHAM, JD

    Most fish species swim with lateral body undulations running from head to tail, These waves run more slowly than the waves of muscle activation causing them, reflecting the effect of the interaction between the fish's body and the reactive forces from the water, The coupling between both waves

  11. The Effect of Endurance Swimming Exercise Training on Structural Remodeling and Apoptotic Index of Adrenal Cortex in Pregnant Rats Exposed to Cadmium Toxicity

    Directory of Open Access Journals (Sweden)

    Saeid Dabagh Nikukheslat

    2018-01-01

    Conclusion: Exercise training in determined intensity increased the structural and morphological complications of cadmium toxicity in the adrenal gland of pregnant rats. So, pregnant mothers are advised to use low-intensity exercises and trainings.

  12. Length dependence of force generation exhibit similarities between rat cardiac myocytes and skeletal muscle fibres.

    Science.gov (United States)

    Hanft, Laurin M; McDonald, Kerry S

    2010-08-01

    According to the Frank-Starling relationship, increased ventricular volume increases cardiac output, which helps match cardiac output to peripheral circulatory demand. The cellular basis for this relationship is in large part the myofilament length-tension relationship. Length-tension relationships in maximally calcium activated preparations are relatively shallow and similar between cardiac myocytes and skeletal muscle fibres. During twitch activations length-tension relationships become steeper in both cardiac and skeletal muscle; however, it remains unclear whether length dependence of tension differs between striated muscle cell types during submaximal activations. The purpose of this study was to compare sarcomere length-tension relationships and the sarcomere length dependence of force development between rat skinned left ventricular cardiac myocytes and fast-twitch and slow-twitch skeletal muscle fibres. Muscle cell preparations were calcium activated to yield 50% maximal force, after which isometric force and rate constants (k(tr)) of force development were measured over a range of sarcomere lengths. Myofilament length-tension relationships were considerably steeper in fast-twitch fibres compared to slow-twitch fibres. Interestingly, cardiac myocyte preparations exhibited two populations of length-tension relationships, one steeper than fast-twitch fibres and the other similar to slow-twitch fibres. Moreover, myocytes with shallow length-tension relationships were converted to steeper length-tension relationships by protein kinase A (PKA)-induced myofilament phosphorylation. Sarcomere length-k(tr) relationships were distinct between all three cell types and exhibited patterns markedly different from Ca(2+) activation-dependent k(tr) relationships. Overall, these findings indicate cardiac myocytes exhibit varied length-tension relationships and sarcomere length appears a dominant modulator of force development rates. Importantly, cardiac myocyte length

  13. Strouhal number for free swimming

    Science.gov (United States)

    Saadat, Mehdi; van Buren, Tyler; Floryan, Daniel; Smits, Alexander; Haj-Hariri, Hossein

    2015-11-01

    In this work, we present experimental results to explore the implications of free swimming for Strouhal number (as an outcome) in the context of a simple model for a fish that consists of a 2D virtual body (source of drag) and a 2D pitching foil (source of thrust) representing cruising with thunniform locomotion. The results validate the findings of Saadat and Haj-Hariri (2012): for pitching foils thrust coefficient is a function of Strouhal number for all gaits having amplitude less than a certain critical value. Equivalently, given the balance of thrust and drag forces at cruise, Strouhal number is only a function of the shape, i.e. drag coefficient and area, and essentially a constant for high enough swimming speeds for which the mild dependence of drag coefficient on the speed vanishes. Furthermore, a dimensional analysis generalizes the findings. A scaling analysis shows that the variation of Strouhal number with cruising speed is functionally related to the variation of body drag coefficient with speed. Supported by ONR MURI Grant N00014-14-1-0533.

  14. Geneva 24 hours swim

    CERN Document Server

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  15. Geneva 24 Hours Swim

    CERN Document Server

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  16. Swimming Pools and Molluscum Contagiosum

    Science.gov (United States)

    ... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

  17. 2012 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  18. Healthy Swimming/Recreational Water

    Science.gov (United States)

    ... Medical Professionals En Español Publications, Data, & Statistics Healthy Swimming Resources Health Promotion Materials Find Your State Training & ... Announcements Outbreak Response Toolkits CDC at Work: Healthy Swimming Fast Facts Index of Water-Related Topics Model ...

  19. Muscle specific changes in length-force characteristics of the calf muscles in the spastic Han-Wistar rat

    DEFF Research Database (Denmark)

    Olesen, Annesofie Thorup; Jensen, Bente Rona; Uhlendorf, Toni L

    2014-01-01

    length, passive stiffness and passive force of spastic GA were decreased whereas those of spastic SO were increased. No mechanical interaction between the calf muscles and TA was found. As GA was lengthened, force from SO and PL declined despite a constant muscle-tendon unit length of SO and PL. However......, the extent of this interaction was not different in the spastic rats. In conclusion, the effects of spasticity on length-force characteristics were muscle specific. The changes seen for GA and PL muscles are consistent with the changes in limb mechanics reported for human patients. Our results indicate......The purpose of the present study was to investigate muscle mechanical properties and mechanical interaction between muscles in the lower hindlimb of the spastic mutant rat. Length-force characteristics of gastrocnemius (GA), soleus (SO) and plantaris (PL) were assessed in anesthetized spastic...

  20. A natação minimiza o retardo no crescimento somático e ósseo de ratos? Does swimming minimize somatic and bone growth delay in rats?

    Directory of Open Access Journals (Sweden)

    Ana Cristina Falcão Esteves

    2010-10-01

    óreo induzidas precocemente no tecido ósseo.The bone formation is regulated by hormonal factors and modified by extrinsic stimuli, such as practice of exercises. The effect of swimming on the somatic and bone growth of female rats subjected to two experimental models to reproduce hormone deficiency was assessed.Twenty-eight Wistar, neonate female rats separated in two groups: Monosodium glutamate (MGlu, n = 14; solution of monosodium glutamate 4.0mg/g, alternate days, first 14 days of life and Saline Group (SAL, n = 14; saline solution. Body weight and measurements of somatic development (latero-lateral axis of the skull, anterior-posterior axis of the skull - LLS / APS - and length of the tail - LT were evaluated from the 1st to the 30th day of life. At 60 days of life, the MGlu group was ovariectomized and SAL just went though surgical stress. Subsequently, half of the animals in each group started the swimming training (12 weeks, 5 days/week, 60 min/session, resulting in the following experimental groups: Sedentary saline (Sedsal, n = 7, Swimming saline (Swisal, n = 7, Sedentary glutamate ovariectomy (SedMGluO, n = 7 and Swimming glutamate ovariectomy (SwiMGluO, n = 7.At the end of the experiment, the right femur was weighed and its length assessed. At the 30 initial days, the MGlu group reduced its body weight and the LLS, APC and LT compared to SAL. At day 60, body weight of MGlu group remained lower and at the end of the experiment it was similar between Swisal and Sedsal groups; SedMGLuO and SwiMGluO groups. However, weight reduction was observed in SedMGlutO compared to SedSAL. Swimming helped the weight of the femur in the SAL and did not alter it between SedMGluO and SwiMGluO, but it increased in Sedsal compared to SedMGluO group. In length, the SwiSal was similar to Sedsal and the same situation occurred between SwiMGluO and SedMGluO. However, Sedsal group presented greater length than SedMGluO. Swimming was not able to reverse the effects caused by situations of

  1. Continuous Aerobic Training in Individualized Intensity Avoids Spontaneous Physical Activity Decline and Improves MCT1 Expression in Oxidative Muscle of Swimming Rats.

    Science.gov (United States)

    Scariot, Pedro P M; Manchado-Gobatto, Fúlvia de Barros; Torsoni, Adriana S; Dos Reis, Ivan G M; Beck, Wladimir R; Gobatto, Claudio A

    2016-01-01

    Although aerobic training has been shown to affect the lactate transport of skeletal muscle, there is no information concerning the effect of continuous aerobic training on spontaneous physical activity (SPA). Because every movement in daily life (i.e., SPA) is generated by skeletal muscle, we think that it is possible that an improvement of SPA could affect the physiological properties of muscle with regard to lactate transport. The aim of this study was to evaluate the effect of 12 weeks of continuous aerobic training in individualized intensity on SPA of rats and their gene expressions of monocarboxylate transporters (MCT) 1 and 4 in soleus (oxidative) and white gastrocnemius (glycolytic) muscles. We also analyzed the effect of continuous aerobic training on aerobic and anaerobic parameters using the lactate minimum test (LMT). Sixty-day-old rats were randomly divided into three groups: a baseline group in which rats were evaluated prior to initiation of the study; a control group (Co) in which rats were kept without any treatment during 12 weeks; and a chronic exercise group (Tr) in which rats swam for 40 min/day, 5 days/week at 80% of anaerobic threshold during 12 weeks. After the experimental period, SPA of rats was measured using a gravimetric method. Rats had their expression of MCTs determined by RT-PCR analysis. In essence, aerobic training is effective in maintaining SPA, but did not prevent the decline of aerobic capacity and anaerobic performance, leading us to propose that the decline of SPA is not fully attributed to a deterioration of physical properties. Changes in SPA were concomitant with changes in MCT1 expression in the soleus muscle of trained rats, suggestive of an additional adaptive response toward increased lactate clearance. This result is in line with our observation showing a better equilibrium on lactate production-remotion during the continuous exercise (LMT). We propose an approach to combat the decline of SPA of rats in their home

  2. Continuous Aerobic Training in Individualized Intensity Avoids Spontaneous Physical Activity Decline and Improves MCT1 Expression in Oxidative Muscle of Swimming Rats

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Menezes Scariot

    2016-04-01

    Full Text Available Although aerobic training has been shown to affect the lactate transport of skeletal muscle, there is no information concerning the effect of continuous aerobic training on spontaneous physical activity (SPA. Because every movement in daily life (i.e. SPA is generated by skeletal muscle, we think that it is possible that an improvement of SPA could affect the physiological properties of muscle with regard to lactate transport. The aim of this study was to evaluate the effect of 12 weeks of continuous aerobic training in individualized intensity on SPA of rats and their gene expressions of monocarboxylate transporters (MCT 1 and 4 in soleus (oxidative and white gastrocnemius (glycolytic muscles. We also analyzed the effect of continuous aerobic training on aerobic and anaerobic parameters using the lactate minimum test (LMT. 60-day-old rats were randomly divided into three groups: a baseline group in which rats were evaluated prior to initiation of the study; a control group (Co in which rats were kept without any treatment during 12 weeks; and a chronic exercise group (Tr in which rats swam for 40min/day, 5 days/week at 80% of anaerobic threshold during 12 weeks. After the experimental period, SPA of rats was measured using a gravimetric method. Rats had their expression of MCTs determined by RT-PCR analysis. In essence, aerobic training is effective in maintaining SPA, but did not prevent the decline of aerobic capacity and anaerobic performance, leading us to propose that the decline of SPA is not fully attributed to a deterioration of physical properties. Changes in SPA were concomitant with changes in MCT1 expression in the soleus muscle of trained rats, suggestive of an additional adaptive response toward increased lactate clearance. This result is in line with our observation showing a better equilibrium on lactate production-remotion during the continuous exercise (LMT. We propose an approach to combat the decline of SPA of rats in their

  3. Effects of Swim Stress on Neophobia and Reconditioning Using a Conditioned Taste Aversion Procedure

    Science.gov (United States)

    Walker, Jennifer M.; Ramsey, Ashley K.; Fowler, Stephanie W.; Schachtman, Todd R.

    2012-01-01

    Previous research has found that swim stress during a classical conditioning trial attenuates conditioned taste aversion (CTA). In the current study, rats were used to examine the effects of inescapable swim stress on the habituation of neophobia to a flavored solution and reacquisition of an extinguished conditioned taste aversion. In Experiment…

  4. CXCR4 antagonist AMD3100 reverses the neurogenesis and behavioral recovery promoted by forced limb-use in stroke rats.

    Science.gov (United States)

    Zhao, Shanshan; Qu, Huiling; Zhao, Yi; Xiao, Ting; Zhao, Mei; Li, Yong; Jolkkonen, Jukka; Cao, Yunpeng; Zhao, Chuansheng

    2015-01-01

    Forced limb-use can enhance neurogenesis and behavioral recovery as well as increasing the level of stromal cell-derived factor-1 (SDF-1) in stroke rats. We examined whether the SDF-1/CXCR4 pathway is involved in the enhanced neurogenesis and promoted behavioral recovery induced by forced limb-use in the chronic phase of stroke. The CXCR4 antagonist, AMD3100, was used to block the SDF-1/CXCR4 pathway in the ischemic rats. Brain ischemia was induced by endothelin-1. One week after ischemia, the unimpaired forelimb of rats was immobilized for 3 weeks. The proliferation, migration, and survival of DCX-positive cells in the subventricular zone (SVZ), and the dendritic complexity of DCX-positive cells in the dentate gyrus (DG), as well as the inflammatory response in the infarcted striatum were analyzed by immunohistochemistry. Functional recovery was assessed in beam-walking and water maze tests. Forced limb-use enhanced the proliferation, migration, dendritic complexity and the survival of newborn neurons. Furthermore, forced limb-use suppressed the inflammatory response and improved both motor and cognitive functions after stroke. AMD3100 significantly abrogated the enhanced neurogenesis and behavioral recovery induced by forced limb-use without influencing the inflammatory response. SDF-1/CXCR4 pathway seems to be involved in the enhancement of neurogenesis and behavioral recovery induced by post-stroke forced limb-use.

  5. Unsteady propulsion by an intermittent swimming gait

    Science.gov (United States)

    Akoz, Emre; Moored, Keith W.

    2018-01-01

    Inviscid computational results are presented on a self-propelled swimmer modeled as a virtual body combined with a two-dimensional hydrofoil pitching intermittently about its leading edge. Lighthill (1971) originally proposed that this burst-and-coast behavior can save fish energy during swimming by taking advantage of the viscous Bone-Lighthill boundary layer thinning mechanism. Here, an additional inviscid Garrick mechanism is discovered that allows swimmers to control the ratio of their added mass thrust-producing forces to their circulatory drag-inducing forces by decreasing their duty cycle, DC, of locomotion. This mechanism can save intermittent swimmers as much as 60% of the energy it takes to swim continuously at the same speed. The inviscid energy savings are shown to increase with increasing amplitude of motion, increase with decreasing Lighthill number, Li, and switch to an energetic cost above continuous swimming for sufficiently low DC. Intermittent swimmers are observed to shed four vortices per cycle that form into groups that are self-similar with the DC. In addition, previous thrust and power scaling laws of continuous self-propelled swimming are further generalized to include intermittent swimming. The key is that by averaging the thrust and power coefficients over only the bursting period then the intermittent problem can be transformed into a continuous one. Furthermore, the intermittent thrust and power scaling relations are extended to predict the mean speed and cost of transport of swimmers. By tuning a few coefficients with a handful of simulations these self-propelled relations can become predictive. In the current study, the mean speed and cost of transport are predicted to within 3% and 18% of their full-scale values by using these relations.

  6. Swimming of the Honey Bees

    Science.gov (United States)

    Roh, Chris; Gharib, Morteza

    2016-11-01

    When the weather gets hot, nursing honey bees nudge foragers to collect water for thermoregulation of their hive. While on their mission to collect water, foragers sometimes get trapped on the water surface, forced to interact with a different fluid environment. In this study, we present the survival strategy of the honey bees at the air-water interface. A high-speed videography and shadowgraph were used to record the honey bees swimming. A unique thrust mechanism through rapid vibration of their wings at 60 to 150 Hz was observed. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1511414; additional support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.

  7. Environmental calcium and variation in yolk sac size influence swimming performance in larval lake sturgeon (Acipenser fulvescens)

    DEFF Research Database (Denmark)

    Deslauriers, David; Svendsen, Jon Christian; Genz, Janet

    2018-01-01

    , because the yolk sac is likely to affect drag forces during swimming. Testing swimming performance of larval A. fulvescens reared in four different calcium treatments spanning the range of 4-132 mg l-1 [Ca2+], this study found no treatment effects on the sprint swimming speed. A novel test of volitional...... reduced swimming performance and could be more susceptible to predation or premature downstream drift. Our study reveals how environmental factors and phenotypic variation influence locomotor performance in a larval fish....

  8. Quantification of the rat left ventricle force and Ca2+ -frequency relationships: similarities to dog and human.

    Science.gov (United States)

    Taylor, David G; Parilak, Leonard D; LeWinter, Martin M; Knot, Harm J

    2004-01-01

    To measure and quantify the force-frequency (FFR) and Ca(2+)-frequency (CaFR) relationships in isolated rat left ventricular (LV) muscle at physiological heart rates and compare the obtained FFR to that measured in larger mammalian muscle from dog and human using the same experimental protocol. Rat papillary muscle was isolated from the LV of adult male Sprague-Dawley rats, and dog and human muscles were from free-wall LV biopsies, loaded with the Ca(2+) indicator Fura-2, allowed to recover from isolation trauma and then subjected to direct electrical stimulation while measuring force production and intracellular Ca(2+) transients. We obtained a positive FFR between 1 and 4 Hz that is qualitatively similar to that found in isolated LV epicardial muscle strips from dogs and humans with normal LV function. The FFR reflects the cytosolic Ca(2+) transients in amplitude. Isoproterenol yielded an enhancement in force, but flattening of the FFR, whereas cyclopiazonic acid caused depression of FFR amplitude without changing frequency-dependent shape. We describe an experimental protocol that consistently yields positive FFRs in rat, dog and human LV muscle at stimulation rates between 1 and 4 Hz, without significant qualitative differences. We attribute previously observed negative FFR in rat muscle to an increase in SERCA activity early after excision and preparation of the muscle strips.

  9. Chronic treatment with caffeine and its withdrawal modify the antidepressant-like activity of selective serotonin reuptake inhibitors in the forced swim and tail suspension tests in mice. Effects on Comt, Slc6a15 and Adora1 gene expression.

    Science.gov (United States)

    Szopa, Aleksandra; Doboszewska, Urszula; Herbet, Mariola; Wośko, Sylwia; Wyska, Elżbieta; Świąder, Katarzyna; Serefko, Anna; Korga, Agnieszka; Wlaź, Aleksandra; Wróbel, Andrzej; Ostrowska, Marta; Terlecka, Joanna; Kanadys, Adam; Poleszak, Ewa; Dudka, Jarosław; Wlaź, Piotr

    2017-12-15

    Recent preclinical and clinical data suggest that low dose of caffeine enhances the effects of common antidepressants. Here we investigated the effects of chronic administration of caffeine (5mg/kg, twice daily for 14days) and its withdrawal on day 15th on the activity of per se ineffective doses of fluoxetine (5mg/kg) and escitalopram (2mg/kg) given on day 15th. We found decreased immobility time in the forced swim and tail suspension tests in mice in which caffeine was administered simultaneously with antidepressants on day 15th following a 14-day caffeine treatment and no alterations in the spontaneous locomotor activity. A decrease in the level of escitalopram and an increase in the level of caffeine in serum were observed after concomitant administration of these compounds, while the joint administration of caffeine and fluoxetine was not associated with changes in their levels in serum or brain. Caffeine withdrawal caused a decrease in Adora1 mRNA level in the cerebral cortex (Cx). Administration of escitalopram or fluoxetine followed by caffeine withdrawal caused an increase in this gene expression, whereas administration of escitalopram, but not fluoxetine, on day 15th together with caffeine caused a decrease in Adora1 mRNA level in the Cx. Furthermore, antidepressant-like activity observed after joint administration of the tested drugs with caffeine was associated with decreased Slc6a15 mRNA level in the Cx. The results show that withdrawal of caffeine after its chronic intake may change activity of antidepressants with concomitant alterations within monoamine, adenosine and glutamate systems. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Traxoprodil, a selective antagonist of the NR2B subunit of the NMDA receptor, potentiates the antidepressant-like effects of certain antidepressant drugs in the forced swim test in mice.

    Science.gov (United States)

    Poleszak, Ewa; Stasiuk, Weronika; Szopa, Aleksandra; Wyska, Elżbieta; Serefko, Anna; Oniszczuk, Anna; Wośko, Sylwia; Świąder, Katarzyna; Wlaź, Piotr

    2016-08-01

    One of the newest substances, whose antidepressant activity was shown is traxoprodil, which is a selective antagonist of the NR2B subunit of the NMDA receptor. The main goal of the present study was to evaluate the effect of traxoprodil on animals' behavior using the forced swim test (FST), as well as the effect of traxoprodil (10 mg/kg) on the activity of antidepressants, such as imipramine (15 mg/kg), fluoxetine (5 mg/kg), escitalopram (2 mg/kg) and reboxetine (2.5 mg/kg). Serotonergic lesion and experiment using the selective agonists of serotonin receptors 5-HT1A and 5-HT2 was conducted to evaluate the role of the serotonergic system in the antidepressant action of traxoprodil. Brain concentrations of tested agents were determined using HPLC. The results showed that traxoprodil at a dose of 20 and 40 mg/kg exhibited antidepressant activity in the FST and it was not related to changes in animals' locomotor activity. Co-administration of traxoprodil with imipramine, fluoxetine or escitalopram, each in subtherapeutic doses, significantly affected the animals' behavior in the FST and, what is important, these changes were not due to the severity of locomotor activity. The observed effect of traxoprodil is only partially associated with serotonergic system and is independent of the effect on the 5-HT1A and 5-HT2 serotonin receptors. The results of an attempt to assess the nature of the interaction between traxoprodil and the tested drugs show that in the case of joint administration of traxoprodil and fluoxetine, imipramine or escitalopram, there were interactions in the pharmacokinetic phase.

  11. Interaction of reelin and stress on immobility in the forced swim test but not dopamine-mediated locomotor hyperactivity or prepulse inhibition disruption: Relevance to psychotic and mood disorders.

    Science.gov (United States)

    Notaras, Michael J; Vivian, Billie; Wilson, Carey; van den Buuse, Maarten

    2017-07-13

    Psychotic disorders, such as schizophrenia, as well as some mood disorders, such as bipolar disorder, have been suggested to share common biological risk factors. One such factor is reelin, a large extracellular matrix glycoprotein that regulates neuronal migration during development as well as numerous activity-dependent processes in the adult brain. The current study sought to evaluate whether a history of stress exposure interacts with endogenous reelin levels to modify behavioural endophenotypes of relevance to psychotic and mood disorders. Heterozygous Reeler Mice (HRM) and wildtype (WT) controls were treated with 50mg/L of corticosterone (CORT) in their drinking water from 6 to 9weeks of age, before undergoing behavioural testing in adulthood. We assessed methamphetamine-induced locomotor hyperactivity, prepulse inhibition (PPI) of acoustic startle, short-term spatial memory in the Y-maze, and depression-like behaviour in the Forced-Swim Test (FST). HRM genotype or CORT treatment did not affect methamphetamine-induced locomotor hyperactivity, a model of psychosis-like behaviour. At baseline, HRM showed decreased PPI at the commonly used 100msec interstimulus interval (ISI), but not at the 30msec ISI or following challenge with apomorphine. A history of CORT exposure potentiated immobility in the FST amongst HRM, but not WT mice. In the Y-maze, chronic CORT treatment decreased novel arm preference amongst HRM, reflecting reduced short-term spatial memory. These data confirm a significant role of endogenous reelin levels on stress-related behaviour, supporting a possible role in both bipolar disorder and schizophrenia. However, an interaction of reelin deficiency with dopaminergic regulation of psychosis-like behaviour remains unclear. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. The role of NMDA receptor and nitric oxide/cyclic guanosine monophosphate pathway in the antidepressant-like effect of dextromethorphan in mice forced swimming test and tail suspension test.

    Science.gov (United States)

    Sakhaee, Ehsan; Ostadhadi, Sattar; Khan, Muhammad Imran; Yousefi, Farbod; Norouzi-Javidan, Abbas; Akbarian, Reyhaneh; Chamanara, Mohsen; Zolfaghari, Samira; Dehpour, Ahmad-Reza

    2017-01-01

    Depression is a devastating disorder which has a high impact on the wellbeing of overall society. As such, need for innovative therapeutic agents are always there. Most of the researchers focused on N-methyl-d-aspartate receptor to explore the antidepressant like activity of new therapeutic agents. Dextromethorphan is a cough suppressant agent with potential antidepressant activity reported in mouse force swimming test. Considering N-methyl-d-aspartate as a forefront in exploring antidepressant agents, here we focused to unpin the antidepressant mechanism of dextromethorphan targeting N-methyl-d-aspartate receptor induced nitric oxide-cyclic guanosine monophosphate signaling. Dextromethorphan administered at a dose of 10 and 30mg/kg i.p significantly reduced the immobility time. Interestingly, this effect of drug (30mg/kg) was inhibited when the animals were pretreated either with N-methyl-d-aspartate (75mg/kg), or l-arginine (750mg/kg) as a nitric oxide precursor and/or sildenafil (5mg/kg) as a phosphodiesterase 5 inhibitor. However, the antidepressant effect of Dextromethorphan subeffective dose (3mg/kg) was augmented when the animals were administered with either L-NG-Nitroarginine methyl ester (10mg/kg) non-specific nitric oxide synthase inhibitor, 7-Nitroindazole (30mg/kg) specific neural nitric oxide synthase inhibitor, MK-801 (0.05mg/kg) an N-methyl-d-aspartate receptor antagonist but not aminoguanidine (50mg/kg) which is specific inducible nitric oxide synthase inhibitor as compared to the drugs when administered alone. No remarkable effect on locomotor activity was observed during open field test when the drugs were administered at the above mentioned doses. Therefore, it is evident that the antidepressant like effect of Dextromethorphan is owed due to its inhibitory effect on N-methyl-d-aspartate receptor and NO- Cyclic guanosine monophosphate pathway. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Voluntary and forced exercise influence the survival and body composition of ageing male rats differently.

    Science.gov (United States)

    Narath, E; Skalicky, M; Viidik, A

    2001-11-01

    The importance of maintaining physical fitness by engaging in exercise in a life-long perspective as well as the avoidance of obesity has been emphasised in recent years by epidemiological studies on human populations as well as studies on laboratory rodents. In laboratory studies, voluntary running in wheels and forced training in a treadmill have been used with beneficial results. Restriction of the food intake of sedentary laboratory rodents can be regarded either as life prolongation or prevention of life shortening by obesity. We compared the effects of these interventions on male Sprague-Dawley rats from the age of 5 to 23 months in the following groups: (1) RW=voluntary running in wheels; (2) PW=fed to pair weight with RW animals; (3) TM=forced training in a treadmill; and (4) S1=sedentary with ad libitum access to food. Each group consisted of 32 animals, all housed individually in cages. Two RW animals died, five died in each of the PW and S1 groups and 10 in the TM group (pmuch they run.

  14. Effect of high wavelengths low intensity light during dark period on physical exercise performance, biochemical and haematological parameters of swimming rats.

    Science.gov (United States)

    Beck, W; Gobatto, C

    2016-03-01

    Nocturnal rodents should be assessed at an appropriate time of day, which leads to a challenge in identifying an adequate environmental light which allows animal visualisation without perturbing physiological homeostasis. Thus, we analysed the influence of high wavelength and low intensity light during dark period on physical exercise and biochemical and haematological parameters of nocturnal rats. We submitted 80 animals to an exhaustive exercise at individualised intensity under two different illuminations during dark period. Red light (> 600 nm; sports performance experiments.

  15. Stirring by swimming bodies

    International Nuclear Information System (INIS)

    Thiffeault, Jean-Luc; Childress, Stephen

    2010-01-01

    We consider the stirring of an inviscid fluid caused by the locomotion of bodies through it. The swimmers are approximated by non-interacting cylinders or spheres moving steadily along straight lines. We find the displacement of fluid particles caused by the nearby passage of a swimmer as a function of an impact parameter. We use this to compute the effective diffusion coefficient from the random walk of a fluid particle under the influence of a distribution of swimming bodies. We compare with the results of simulations. For typical sizes, densities and swimming velocities of schools of krill, the effective diffusivity in this model is five times the thermal diffusivity. However, we estimate that viscosity increases this value by two orders of magnitude.

  16. Quiet swimming at low Reynolds number

    Science.gov (United States)

    Andersen, Anders; Wadhwa, Navish; Kiørboe, Thomas

    2015-04-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws are valid surprisingly close to the organism. Finally, we discuss point force models as a general framework for hypothesis generation and experimental exploration of fluid mediated predator-prey interactions in the planktonic world.

  17. Tooth movement and changes in periodontal tissue in response to orthodontic force in rats vary depending on the time of day the force is applied.

    Science.gov (United States)

    Miyoshi, K; Igarashi, K; Saeki, S; Shinoda, H; Mitani, H

    2001-08-01

    The purpose of this study was to investigate whether there are any differences in tooth movement or in the response of periodontal tissue to orthodontic force when the force is applied at different times of the day. One hundred 6-week-old male Wistar rats were divided into one control group without force application and three experimental groups based on the time of day the force was applied to the upper first molars. Animals in the whole-day group received force continuously throughout the experimental period, while animals in the light- and dark-period groups received force only during the light (07:00-19:00) or dark period (19:00-07:00), respectively. Tooth movement was measured using the occlusal view of a precise plaster model with a profile projector. Periodontal tissues were evaluated histologically. The time course of tooth movement varied among the groups. Tooth movement over 21 days in the whole-day and light-period groups was about twice that as in the dark-period group. The formation of new bone on the tension side in the whole-day and light-period groups was more than twice that as in the dark-period group. On the pressure side, more osteoclasts appeared on the alveolar bone in the whole-day and light-period groups than in the dark-period group. The light-period group showed less extensive hyalinization of the periodontal ligament (PDL) than the whole-day group. The area of root resorption on day 21 also varied among the groups. Interference by masticatory forces did not seem to be a principal cause of the decreased tooth movement in the dark-period group. These results indicate that there are considerable variations in tooth movement and in the response of periodontal tissue to orthodontic force when the force is applied at different times of the day in rats. The results suggest that diurnal rhythms in bone metabolism have important implications in orthodontic treatment.

  18. Swimming Dynamics of the Lyme Disease Spirochete

    Science.gov (United States)

    Vig, Dhruv K.; Wolgemuth, Charles W.

    2012-11-01

    The Lyme disease spirochete, Borrelia burgdorferi, swims by undulating its cell body in the form of a traveling flat wave, a process driven by rotating internal flagella. We study B. burgdorferi’s swimming by treating the cell body and flagella as linearly elastic filaments. The dynamics of the cell are then determined from the balance between elastic and resistive forces and moments. We find that planar, traveling waves only exist when the flagella are effectively anchored at both ends of the bacterium and that these traveling flat waves rotate as they undulate. The model predicts how the undulation frequency is related to the torque from the flagellar motors and how the stiffness of the cell body and flagella affect the undulations and morphology.

  19. Unsteady computational fluid dynamics in front crawl swimming.

    Science.gov (United States)

    Samson, Mathias; Bernard, Anthony; Monnet, Tony; Lacouture, Patrick; David, Laurent

    2017-05-01

    The development of codes and power calculations currently allows the simulation of increasingly complex flows, especially in the turbulent regime. Swimming research should benefit from these technological advances to try to better understand the dynamic mechanisms involved in swimming. An unsteady Computational Fluid Dynamics (CFD) study is conducted in crawl, in order to analyse the propulsive forces generated by the hand and forearm. The k-ω SST turbulence model and an overset grid method have been used. The main objectives are to analyse the evolution of the hand-forearm propulsive forces and to explain this relative to the arm kinematics parameters. In order to validate our simulation model, the calculated forces and pressures were compared with several other experimental and numerical studies. A good agreement is found between our results and those of other studies. The hand is the segment that generates the most propulsive forces during the aquatic stroke. As the pressure component is the main source of force, the orientation of the hand-forearm in the absolute coordinate system is an important kinematic parameter in the swimming performance. The propulsive forces are biggest when the angles of attack are high. CFD appears as a very valuable tool to better analyze the mechanisms of swimming performance and offers some promising developments, especially for optimizing the performance from a parametric study.

  20. Swimming education in Australian society.

    OpenAIRE

    Lynch, TJ

    2014-01-01

    Abstract: The purpose of this paper is to explore a community swimming program using autoethnography qualitative research. Autoethnography is an approach to research and writing that seeks to describe and systematically analyze (graphy) personal experience (auto) in order to understand cultural experience (ethno) (Ellis 2004; Holman Jones 2005). Through childhood reflection of lived swimming experiences, and adult life reflection of lived swimming teaching experiences as a primary school teac...

  1. Mechanics of undulatory swimming in a frictional fluid.

    Science.gov (United States)

    Ding, Yang; Sharpe, Sarah S; Masse, Andrew; Goldman, Daniel I

    2012-01-01

    The sandfish lizard (Scincus scincus) swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. In previous work we predicted average swimming speed by developing a numerical simulation that incorporated experimentally measured biological kinematics into a multibody sandfish model. The model was coupled to an experimentally validated soft sphere discrete element method simulation of the granular medium. In this paper, we use the simulation to study the detailed mechanics of undulatory swimming in a "granular frictional fluid" and compare the predictions to our previously developed resistive force theory (RFT) which models sand-swimming using empirically determined granular drag laws. The simulation reveals that the forward speed of the center of mass (CoM) oscillates about its average speed in antiphase with head drag. The coupling between overall body motion and body deformation results in a non-trivial pattern in the magnitude of lateral displacement of the segments along the body. The actuator torque and segment power are maximal near the center of the body and decrease to zero toward the head and the tail. Approximately 30% of the net swimming power is dissipated in head drag. The power consumption is proportional to the frequency in the biologically relevant range, which confirms that frictional forces dominate during sand-swimming by the sandfish. Comparison of the segmental forces measured in simulation with the force on a laterally oscillating rod reveals that a granular hysteresis effect causes the overestimation of the body thrust forces in the RFT. Our models provide detailed testable predictions for biological locomotion in a granular environment.

  2. Comparisons of orthodontic root resorption under heavy and jiggling reciprocating forces during experimental tooth movement in a rat model.

    Science.gov (United States)

    Hikida, Takuji; Yamaguchi, Masaru; Shimizu, Mami; Kikuta, Jun; Yoshino, Tomokazu; Kasai, Kazutaka

    2016-07-01

    Root mobility due to reciprocating movement of the tooth (jiggling) may exacerbate orthodontic root resorption (ORR). "Jiggling" describes mesiodistal or buccolingual movement of the roots of the teeth during orthodontic treatment. In the present study, buccolingual movement is described as "jiggling." We aimed to investigate the relationship between ORR and jiggling and to test for positive cell expression in odontoclasts in resorbed roots during experimental tooth movement (jiggling) in vivo. Male Wistar rats were divided into control, heavy force (HF), optimal force (OF), and jiggling force (JF) groups. The expression levels of cathepsin K, matrix metalloproteinase (MMP)-9 protein, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant 1 (CINC-1; an IL-8-related protein in rodents), receptor activator of nuclear factor κB ligand (RANKL), and osteoprotegerin protein in the dental root were determined using immunohistochemistry. On day 21, a greater number of root resorption lacunae, which contained multinucleated odontoclasts, were observed in the palatal roots of rats in the JF group than in rats from other groups. Furthermore, there was a significant increase in the numbers of cathepsin K-positive and MMP-9-positive odontoclasts in the JF group on day 21. Immunoreactivities for IL-6, CINC-1, and RANKL were stronger in resorbed roots exposed to jiggling than in the other groups on day 21. Negative reactivity was observed in the controls. These results suggest that jiggling may induce ORR via inflammatory cytokine production during orthodontic tooth movement, and that jiggling may be a risk factor for ORR.

  3. Kinematics of swimming and thrust production during powerstroking bouts of the swim frenzy in green turtle hatchlings

    Directory of Open Access Journals (Sweden)

    David T. Booth

    2014-09-01

    Full Text Available Hatchling sea turtles emerge from nests, crawl down the beach and enter the sea where they typically enter a stereotypical hyperactive swimming frenzy. During this swim the front flippers are moved up and down in a flapping motion and are the primary source of thrust production. I used high-speed video linked with simultaneous measurement of thrust production in tethered hatchlings, along with high-speed video of free swimming hatchlings swimming at different water speeds in a swim flume to investigate the links between kinematics of front flipper movement, thrust production and swimming speed. In particular I tested the hypotheses that (1 increased swimming speed is achieved through an increased stroke rate; (2 force produced per stroke is proportional to stroke amplitude, (3 that forward thrust is produced during both the down and up phases of stroking; and (4 that peak thrust is produced towards the end of the downstroke cycle. Front flipper stroke rate was independent of water speed refuting the hypothesis that swimming speed is increased by increasing stroke rate. Instead differences in swimming speed were caused by a combination of varying flipper amplitude and the proportion of time spent powerstroking. Peak thrust produced per stroke varied within and between bouts of powerstroking, and these peaks in thrust were correlated with both flipper amplitude and flipper angular momentum during the downstroke supporting the hypothesis that stroke force is a function of stroke amplitude. Two distinct thrust production patterns were identified, monophasic in which a single peak in thrust was recorded during the later stages of the downstroke, and biphasic in which a small peak in thrust was recorded at the very end of the upstroke and this followed by a large peak in thrust during the later stages of the downstroke. The biphasic cycle occurs in ∼20% of hatchlings when they first started swimming, but disappeared after one to two hours of

  4. Swimming behavior and prey retention of the polychaete larvae Polydora ciliata (Johnston)

    DEFF Research Database (Denmark)

    Hansen, B.W.; Jakobsen, Hans Henrik; Andersen, Anders Peter

    2010-01-01

    in specific feeding rates and the observed increase in the difference between upward and downward swimming speeds with larval size. We estimated a critical larval length above which the buoyancy-corrected weight of the larva exceeds the propulsion force generated by the ciliary swimming apparatus and thus......The behavior of the ubiquitous estuarine planktotrophic spionid polychaete larvae Polydora ciliata was studied. We describe ontogenetic changes in morphology, swimming speed and feeding rates and have developed a simple swimming model using low Reynolds number hydrodynamics. In the model we assumed...... that the ciliary swimming apparatus is primarily composed of the prototroch and secondarily by the telotroch. The model predicted swimming speeds and feeding rates that corresponded well with the measured speeds and rates. Applying empirical data to the model, we were able to explain the profound decrease...

  5. Effect of fish oil and coconut fat supplementation on depressive-type behavior and corticosterone levels of prenatally stressed male rats.

    Science.gov (United States)

    Borsonelo, Elizabethe Cristina; Suchecki, Deborah; Galduróz, José Carlos Fernandes

    2011-04-18

    Prenatal stress (PNS) during critical periods of brain development has been associated with numerous behavioral and/or mood disorders in later life. These outcomes may result from changes in the hypothalamic-pituitary-adrenal (HPA) axis activity, which, in turn, can be modulated by environmental factors, such as nutritional status. In this study, the adult male offspring of dams exposed to restraint stress during the last semester of pregnancy and fed different diets were evaluated for depressive-like behavior in the forced swimming test and for the corticosterone response to the test. Female Wistar rats were allocated to one of three groups: regular diet, diet supplemented with coconut fat or with fish oil, offered during pregnancy and lactation. When pregnancy was confirmed, they were distributed into control or stress groups. Stress consisted of restraint and bright light for 45 min, three times per day, in the last week of pregnancy. The body weight of the adult offspring submitted to PNS was lower than that of controls. In the forced swimming test, time of immobility was reduced and swimming was increased in PNS rats fed fish oil and plasma corticosterone levels immediately after the forced swimming test were lower in PNS rats fed regular diet than their control counterparts; this response was reduced in control rats whose mothers were fed fish oil and coconut fat. The present results indicate that coconut fat and fish oil influenced behavioral and hormonal responses to the forced swimming test in both control and PNS adult male rats. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Paramecia swimming in viscous flow

    Science.gov (United States)

    Zhang, P.; Jana, S.; Giarra, M.; Vlachos, P. P.; Jung, S.

    2015-12-01

    Ciliates like Paramecia exhibit fore-aft asymmetry in their body shapes, and preferentially swim in the direction of the slender anterior rather than the wider posterior. However, the physical reasons for this preference are not well understood. In this work, we propose that specific features of the fluid flow around swimming Paramecia confer some energetic advantage to the preferred swimming direction. Therefore, we seek to understand the effects of body asymmetry and swimming direction on the efficiency of swimming and the flux of fluid into the cilia layer (and thus of food into the oral groove), which we assumed to be primary factors in the energy budgets of these organisms. To this end, we combined numerical techniques (the boundary element method) and laboratory experiments (micro particle image velocimetry) to develop a quantitative model of the flow around a Paramecium and investigate the effect of the body shape on the velocity fields, as well as on the swimming and feeding behaviors. Both simulation and experimental results show that velocity fields exhibit fore-aft asymmetry. Moreover, the shape asymmetry revealed an increase of the fluid flux into the cilia layer compared to symmetric body shapes. Under the assumption that cilia fluid intake and feeding efficiency are primary factors in the energy budgets of Paramecia, our model predicts that the anterior swimming direction is energetically favorable to the posterior swimming direction.

  7. Induction of habits in rats by a forced-choice procedure in T-maze and the effect of pre-test free exploration

    DEFF Research Database (Denmark)

    Moustgaard, Anette; Hau, Jann

    2009-01-01

    the opportunity to explore the entire maze immediately before the free-choice challenge after 200 forced-choice trials, this resulted in a large variation in the choice pattern of the individual rats, and a subgroup of rats choose the newly opened maze arm in 95-100% of the 20 free-choice trials....

  8. London 2012 Paralympic swimming: passive drag and the classification system.

    Science.gov (United States)

    Oh, Yim-Taek; Burkett, Brendan; Osborough, Conor; Formosa, Danielle; Payton, Carl

    2013-09-01

    The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ = -0.41, p < 0.01) and normalised drag and the swimming class (τ = -0.60, p < 0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (r(P) = -0.40, p < 0.01). Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups.

  9. Treinamento de natação na intensidade do limiar anaeróbio melhora a aptidão funcional de ratos idosos Swimming training at anaerobic threshold intensity improves the functional fitness of older rats

    Directory of Open Access Journals (Sweden)

    Verusca Najara de Carvalho Cunha

    2008-12-01

    3-min with blood lactate measurements. The LT was determined by visual inspection of the blood lactate breakpoint. The training program comprised of 30-min swimming/day, 5 days/week, loaded with 5% body mass (BM, or control without exercise. Significant increase on the LT intensity after training (pre = 4.5 ± 1.1 vs. post = 5.4 ± 0.9% BM. The maximal workload reached at the end of incremental test increased significantly from 39.7 ± 7.5 g on pre to 48.4 ± 10.5 g at post training, with no changes for the control group (44.7 ± 8 vs. 45.3 ± 9.3 g. The body mass of the trained group did not change as a result of 4 weeks of swimming at LT intensity (641.0 ± 62.0 to 636.0 ± 72.7 g; p > 0.05. On the other hand, the untrained group increased significantly the BM from 614.0 ± 80.0 to 643.0 ± 72.7 g. The maximal workload, as expressed both in relation to absolute and relative values (i.e. %BM increased significantly only as a result of training. It was concluded that four weeks of swimming training at LT intensity resulted in aerobic fitness improvement and body mass maintenance of older rats.

  10. Causal Link between the Cortico-Rubral Pathway and Functional Recovery through Forced Impaired Limb Use in Rats with Stroke

    Science.gov (United States)

    Ishida, Akimasa; Isa, Kaoru; Umeda, Tatsuya; Kobayashi, Kazuto; Kobayashi, Kenta; Hida, Hideki

    2016-01-01

    Intensive rehabilitation is believed to induce use-dependent plasticity in the injured nervous system; however, its causal relationship to functional recovery is unclear. Here, we performed systematic analysis of the effects of forced use of an impaired forelimb on the recovery of rats after lesioning the internal capsule with intracerebral hemorrhage (ICH). Forced limb use (FLU) group rats exhibited better recovery of skilled forelimb functions and their cortical motor area with forelimb representation was restored and enlarged on the ipsilesional side. In addition, abundant axonal sprouting from the reemerged forelimb area was found in the ipsilateral red nucleus after FLU. To test the causal relationship between the plasticity in the cortico-rubral pathway and recovery, loss-of-function experiments were conducted using a double-viral vector technique, which induces selective blockade of the target pathway. Blockade of the cortico-rubral tract resulted in deficits of the recovered forelimb function in FLU group rats. These findings suggest that the cortico-rubral pathway is a substrate for recovery induced by intensive rehabilitation after ICH. SIGNIFICANCE STATEMENT The research aimed at determining the causal linkage between reorganization of the motor pathway induced by intensive rehabilitative training and recovery after stroke. We clarified the expansion of the forelimb representation area of the ipsilesional motor cortex by forced impaired forelimb use (FLU) after lesioning the internal capsule with intracerebral hemorrhaging (ICH) in rats. Anterograde tracing showed robust axonal sprouting from the forelimb area to the red nucleus in response to FLU. Selective blockade of the cortico-rubral pathway by the novel double-viral vector technique clearly revealed that the increased cortico-rubral axonal projections had causal linkage to the recovery of reaching movements induced by FLU. Our data demonstrate that the cortico-rubral pathway is responsible for the

  11. The Impact of Baby Swimming on Introductory and Elementary Swimming Training

    OpenAIRE

    Břízová, Gabriela

    2007-01-01

    THESIS ANNOTATION Title: The Impact of Baby Swimming on Introductory and Elementary Swimming Training Aim: To assess the impact of 'baby swimming' on the successfulness in introductory and partly in elementary swimming training, and to find out whether also other circumstances (for example the length of attendance at 'baby swimming') have some influence on introductory swimming training. Methods: We used a questionnaire method for the parents of children who had attended 'baby swimming' and f...

  12. Swimming level of pupils from elementary schools with own swimming pool

    OpenAIRE

    Zálupská, Klára

    2012-01-01

    Title: Swimming level of pupils from primary school with private swimming pool. Work objectives: The aim is to identify assess level of swimming of pupils from first to ninth grade of primary school with a private pool in Chomutov district using continuous swimming test with regular swimming lessons, which is started in the first grade and persists until the ninth grade. The condition was organizing a school swimming lessons once a week for 45 minutes in all grades. Methodology: Swimming leve...

  13. Exercise-training intervention studies in competitive swimming.

    Science.gov (United States)

    Aspenes, Stian Thoresen; Karlsen, Trine

    2012-06-01

    Competitive swimming has a long history and is currently one of the largest Olympic sports, with 16 pool events. Several aspects separate swimming from most other sports such as (i) the prone position; (ii) simultaneous use of arms and legs for propulsion; (iii) water immersion (i.e. hydrostatic pressure on thorax and controlled respiration); (iv) propulsive forces that are applied against a fluctuant element; and (v) minimal influence of equipment on performance. Competitive swimmers are suggested to have specific anthropometrical features compared with other athletes, but are nevertheless dependent on physiological adaptations to enhance their performance. Swimmers thus engage in large volumes of training in the pool and on dry land. Strength training of various forms is widely used, and the energetic systems are addressed by aerobic and anaerobic swimming training. The aim of the current review was to report results from controlled exercise training trials within competitive swimming. From a structured literature search we found 17 controlled intervention studies that covered strength or resistance training, assisted sprint swimming, arms-only training, leg-kick training, respiratory muscle training, training the energy delivery systems and combined interventions across the aforementioned categories. Nine of the included studies were randomized controlled trials. Among the included studies we found indications that heavy strength training on dry land (one to five repetitions maximum with pull-downs for three sets with maximal effort in the concentric phase) or sprint swimming with resistance towards propulsion (maximal pushing with the arms against fixed points or pulling a perforated bowl) may be efficient for enhanced performance, and may also possibly have positive effects on stroke mechanics. The largest effect size (ES) on swimming performance was found in 50 m freestyle after a dry-land strength training regimen of maximum six repetitions across three

  14. Attenuated Increase in Maximal Force of Rat Medial Gastrocnemius Muscle after Concurrent Peak Power and Endurance Training

    Directory of Open Access Journals (Sweden)

    Regula Furrer

    2013-01-01

    Full Text Available Improvement of muscle peak power and oxidative capacity are generally presumed to be mutually exclusive. However, this may not be valid by using fibre type-specific recruitment. Since rat medial gastrocnemius muscle (GM is composed of high and low oxidative compartments which are recruited task specifically, we hypothesised that the adaptive responses to peak power training were unaffected by additional endurance training. Thirty rats were subjected to either no training (control, peak power training (PT, or both peak power and endurance training (PET, which was performed on a treadmill 5 days per week for 6 weeks. Maximal running velocity increased 13.5% throughout the training and was similar in both training groups. Only after PT, GM maximal force was 10% higher than that of the control group. In the low oxidative compartment, mRNA levels of myostatin and MuRF-1 were higher after PT as compared to those of control and PET groups, respectively. Phospho-S6 ribosomal protein levels remained unchanged, suggesting that the elevated myostatin levels after PT did not inhibit mTOR signalling. In conclusion, even by using task-specific recruitment of the compartmentalized rat GM, additional endurance training interfered with the adaptive response of peak power training and attenuated the increase in maximal force after power training.

  15. An experimental study on effect of antioxidant vitamin E in stress and alcohol induced changes in male fertility in albino rats.

    Directory of Open Access Journals (Sweden)

    Sanghishetti Vijay Prasad, Nayak BB, Ghongane BB, Raul AR, Vijay Kumar AN, Mutalik MM, Kapure NL.

    2012-09-01

    Full Text Available Introduction: Physical and Psychological stresses are believed to reduce sexual functions, resulting fromneurotransmission changes in various erectile response pathways and reduced blood flow in genital organs.Intake of alcohol depends on numerous genetic and environmental factors. Stress has long been thought to influence the alcohol drinking in humans. Forced swimming in laboratory animals has been widely used as a model of stress to study the physiological changes and the capacity of the organism in response to stress. Aim: 1. To assess the effect of forced swimming stress on seminal fluid profile, Serum testosterone level, Testicular lipid peroxidation levels. 2. To assess the effect of Vitamin E on stress induced changes. Method: Adult male albino rats weighing 200 – 220 g, aged 12-15 weeks were used in this study. The animals were randomly divided into four groups of 6 animals each. Group1 (control received distilled water, Group 2 (Forced Swimming Stress received distilled water Group 3: subjected to Forced Swimming stress with 20% alcohol intake p.o. Group 4: Swimming stress with 20% alcohol treated with Vitamin E(200mg/kg/day orally. The following parameters were studied in all groups 1. Body weight. 2. Sperm count Motility and Life /death Ratio (SLDR. 3. Serum Testosterone 4. Testicular Malondialdehyde level (MDA. Results: Forced swimming stress caused loss in body wt, reduction in sperm count, motility and SLDR in sperm analysis, reduction in serum testosterone and increase testicular MDA levels compared to control. All the changes were statistically significant. When alcohol was added along with forced swimming it caused further loss in body wt, sperm count, motility and SLDR, serum testosterone level and slightly further increase in MDA levels. These observations were also statistically significant. In case of group IV in which Vitamin E was administered long with stress with alcohol it showed a trend of reversal phenomenon of

  16. Mechanical Study of Standard Six Beat Front Crawl Swimming by Using Swimming Human Simulation Model

    Science.gov (United States)

    Nakashima, Motomu

    There are many dynamical problems in front crawl swimming which have not been fully investigated by analytical approaches. Therefore, in this paper, standard six beat front crawl swimming is analyzed by the swimming human simulation model SWUM, which has been developed by the authors. First, the outline of the simulation model, the joint motion for one stroke cycle, and the specifications of calculation are described respectively. Next, contribution of each fluid force component and of each body part to the thrust, effect of the flutter kick, estimation of the active drag, roll motion, and the propulsive efficiency are discussed respectively. The following results were theoretically obtained: The thrust is produced at the upper limb by the normal drag force component. The flutter kick plays a role in raising the lower half of the body. The active drag coefficient in the simulation becomes 0.082. Buoyancy determines the primal wave of the roll motion fluctuation. The propulsive efficiency in the simulation becomes 0.2.

  17. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Roebert, G.A.

    1978-01-01

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  18. Swimming Performance and Metabolism of Golden Shiners

    Science.gov (United States)

    The swimming ability and metabolism of golden shiners, Notemigonus crysoleucas, was examined using swim tunnel respirometery. The oxygen consumption and tail beat frequencies at various swimming speeds, an estimation of the standard metabolic rate, and the critical swimming speed (Ucrit) was determ...

  19. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

  20. Swimming ability and physiological response to swimming fatigue in ...

    African Journals Online (AJOL)

    The swimming endurance of kuruma shrimp, Marsupenaeus japonicus (11.04 ± 2.43 g) at five swimming speeds (23.0, 26.7, 31.0, 34.6 and 38.6 cm s-1) was determined in a circulating flume at 25.7 ± 0.7°C. The plasma glucose and total protein, hepatopancreas and pleopods muscle glycogen concentrations were ...

  1. Swimming literacy field hockey woman player ground.

    OpenAIRE

    Baštová, Miroslava

    2012-01-01

    Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...

  2. System Wide Information Management (SWIM)

    Science.gov (United States)

    Hritz, Mike; McGowan, Shirley; Ramos, Cal

    2004-01-01

    This viewgraph presentation lists questions regarding the implementation of System Wide Information Management (SWIM). Some of the questions concern policy issues and strategies, technology issues and strategies, or transition issues and strategies.

  3. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  4. Interferência dos ácidos graxos ômega-3 nos lipídeos sangüíneos de ratos submetidos ao exercício de natação Omega-3 fatty acids interference on the blood lipids of rats subjected to swimming exercise

    Directory of Open Access Journals (Sweden)

    Bettina Moritz

    2008-12-01

    as concentrações de lipídeos sangüíneos.OBJECTIVE: To investigate the effects of omega-3 fatty acid supplementation at doses of 0.5 and 1.0g/kg/day on the blood lipids of rats submitted or not to swimming exercise. METHODS: Wistar rats were divided into the following groups: control, control+swimming, omega-3 fatty acids and omega-3 fatty acids+swimming. The omega-3 fatty acids and omega-3 fatty acids+swimming groups received supplements by gavage, while the remaining animals received water by the same method. The control+swimming and omega-3 fatty acids +swimming groups were submitted to exercise. Plasma concentrations of total cholesterol, triglycerides and HDL were determined before and after the experimental procedures. RESULTS: The concentrations of total cholesterol in the 0.5g/kg/day groups reduced proportionally more in the omega-3 fatty acids+swimming group, even though total cholesterol of the control+swimming and omega-3 fatty acids groups also decreased. Total cholesterol decreased in both groups receiving 1.0g/kg/day supplementation, but the decrease was higher in the omega-3 fatty acids+swimming group than in the omega-3 fatty acids group. Triglycerides also decreased in all experimental groups. The greatest decrease was seen in the omega-3 fatty acids+swimming group receiving 0.5g/kg/day supplementation. In the 1.0g/kg/day protocol, the decrease was significant in both groups: the omega-3 fatty acids and omega-3 fatty acids+swimming groups. HDL increased among the non-supplemented animals and decreased among the animals receiving a supplementation of 1.0g/kg/day. CONCLUSION: Omega-3 fatty acid supplementation at doses of 0.5 or 1.0g/kg/day associated with swimming exercise reduced plasma concentrations of total cholesterol and triglycerides, yet additional studies, including varying doses, are necessary to better understand the relationship between ingestion of fish oil and blood lipid concentrations.

  5. A Simple Method for Determination of Critical Swimming Velocity in Swimming Flume

    OpenAIRE

    高橋, 繁浩; 若吉, 浩二; Shigehiro, TAKAHASHI; Kohji, WAKAYOSHI; 中京大学; 奈良教育大学教育学部

    2001-01-01

    The purpose of this study was to investigate a simple method for determination of critical swimming velocity (Vcri). Vcri is defined by Wakayoshi et al. (1992) as the swimming speed which could theoretically be maintained forever without exhaustion, and is expressed as the slope of a regression line between swimming distance (D) and swimming time (T) obtained at various swimming speeds. To determine Vcri, 20 well-trained swimmers were measured at several swimming speeds ranging from 1.25 m/se...

  6. Swimming with the Shoal

    Science.gov (United States)

    Childs, Ann

    2017-10-01

    This article responds to Yuli Rahmawati and Peter Charles Taylor's piece and explores my role as a science teacher, science teacher educator and researcher in two contexts, Sierra Leone and Bhutan. In the first part of the article I reflect on my 3 years as a science teacher in Sierra Leone and demonstrate resonances with Yuli's accounts of culture shock and with her positioning of herself in a third space. I also reflect on the importance of colleagues in helping me reshape my identity as a science teacher in this new context. The second part of the article reflects on much shorter periods of time in Bhutan and my work as a teacher educator and researcher where, unlike Sierra Leone, it was not possible because of the short periods I worked there, to occupy a third space. I close by discussing how in Bhutan, but also Sierra Leone, collaboration with colleagues allowed me to contribute my own expertise, despite my lack of a deep understanding of the cultural context, in a way that was as valuable as possible. I liken this way of collaborative working in my professional life as `swimming with the shoal'.

  7. Solar swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

  8. Distribution of sup 3 H-proline within transseptal fibers of the rat following release of orthodontic forces

    Energy Technology Data Exchange (ETDEWEB)

    Row, K.L.; Johnson, R.B. (Univ. of Manitoba, Winnipeg (Canada))

    1990-10-01

    Maxillary right first molar teeth of rats were tipped mesially with an orthodontic appliance for 2 weeks (experimental group), {sup 3}H-proline was injected, and orthodontic forces were removed 6 hr later (time 0). The contralateral molar teeth of treated (internal control group) and age- and weight-matched untreated animals (external control group) were also studied. Diastemata were created between the molar teeth by the orthodontic appliance, and transseptal fibers between first and second (P less than 0.001) and second and third molars (P less than 0.005) were significantly lengthened as compared to external and internal controls at time 0. Diastemata between molar teeth were closed 5 days after removal of orthodontic force. Transseptal fibers adjacent to the source of the orthodontic force (mesial region) had the highest mean number of {sup 3}H-proline-labeled proteins at time 0 and at all times following removal of the force (P less than 0.001), and had the highest rate of labeled protein removal (P less than 0.001). Half-lives for removal of 3H-proline-labeled transseptal fiber proteins were significantly greater in mesial and distal regions and significantly less in middle regions of experimentals than in corresponding regions of external controls (P less than 0.001).

  9. Distribution of 3H-proline within transseptal fibers of the rat following release of orthodontic forces

    International Nuclear Information System (INIS)

    Row, K.L.; Johnson, R.B.

    1990-01-01

    Maxillary right first molar teeth of rats were tipped mesially with an orthodontic appliance for 2 weeks (experimental group), 3 H-proline was injected, and orthodontic forces were removed 6 hr later (time 0). The contralateral molar teeth of treated (internal control group) and age- and weight-matched untreated animals (external control group) were also studied. Diastemata were created between the molar teeth by the orthodontic appliance, and transseptal fibers between first and second (P less than 0.001) and second and third molars (P less than 0.005) were significantly lengthened as compared to external and internal controls at time 0. Diastemata between molar teeth were closed 5 days after removal of orthodontic force. Transseptal fibers adjacent to the source of the orthodontic force (mesial region) had the highest mean number of 3 H-proline-labeled proteins at time 0 and at all times following removal of the force (P less than 0.001), and had the highest rate of labeled protein removal (P less than 0.001). Half-lives for removal of 3H-proline-labeled transseptal fiber proteins were significantly greater in mesial and distal regions and significantly less in middle regions of experimentals than in corresponding regions of external controls (P less than 0.001)

  10. Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins.

    Science.gov (United States)

    Tian, Jinge; Yu, Tingting; Xu, Yongming; Pu, Shaofeng; Lv, Yingying; Zhang, Xin; DU, Dongping

    2018-01-01

    Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT.

  11. Hydrodynamic advantages of swimming by salp chains.

    Science.gov (United States)

    Sutherland, Kelly R; Weihs, Daniel

    2017-08-01

    Salps are marine invertebrates comprising multiple jet-propelled swimming units during a colonial life-cycle stage. Using theory, we show that asynchronous swimming with multiple pulsed jets yields substantial hydrodynamic benefit due to the production of steady swimming velocities, which limit drag. Laboratory comparisons of swimming kinematics of aggregate salps ( Salpa fusiformis and Weelia cylindrica ) using high-speed video supported that asynchronous swimming by aggregates results in a smoother velocity profile and showed that this smoother velocity profile is the result of uncoordinated, asynchronous swimming by individual zooids. In situ flow visualizations of W. cylindrica swimming wakes revealed that another consequence of asynchronous swimming is that fluid interactions between jet wakes are minimized. Although the advantages of multi-jet propulsion have been mentioned elsewhere, this is the first time that the theory has been quantified and the role of asynchronous swimming verified using experimental data from the laboratory and the field. © 2017 The Author(s).

  12. Padronização de um protocolo experimental de treinamento periodizado em natação utilizando ratos Wistar Standardization of an experimental periodized training protocol in swimming rats

    Directory of Open Access Journals (Sweden)

    Gustavo Gomes de Araujo

    2010-02-01

    Full Text Available Verificar os efeitos de 12 semanas de treinamento periodizado de natação em ratos sobre os valores de glicogênio muscular (GM e hepático (GH, capacidade aeróbia (LAn e anaeróbia (Tlim e creatina quinase (CK. Foram utilizados 70 ratos da linhagem Wistar com 60 dias, adaptados individualmente ao meio líquido por duas semanas. Os animais foram divididos em grupos: controle (GC, n = 40 e periodizado (GP, n = 30; a intensidade do treinamento foi equivalente ao peso corporal do animal (% do PC. O treinamento (T para o GP foi dividido em períodos preparatório básico (PPB, seis semanas, específico (PPE, 4,5 semanas e polimento (PP, 1,5 semana, tendo como estímulos intensidades leve (4% do PC, moderada (5% do PC, pesada (6% do PC e intensa (13% do PC. Vinte e quatro horas após a adaptação, 10 ratos do GC foram sacrificados e avaliados pelo teste de lactato mínimo para mensuração dos valores de linha de base de GM, GH, CK, LAn e Tlim. Os dez animais restantes do GC e GP foram sacrificados ao final de cada período de T. O treinamento periodizado aumentou a concentração de glicogênio muscular ao final do período de polimento. O glicogênio hepático não se alterou no GC, porém no GP houve redução significativa no início do período específico com elevação no período de polimento. A concentração de CK não se modificou ao final dos PPB, PPE e PP. O LAn reduziu ao longo do período experimental no GC, mas ao final do PP para o GP, o LAn atingiu os mesmos valores do início do treinamento. O Tlim aumentou no PP. Desse modo, pode-se concluir que o treinamento periodizado provocou supercompensação energética ao final da periodização. A capacidade anaeróbia aumentou no PP bem como o LAn, que obteve maiores valores em relação ao GC nesse período.The objective of this study was to verify the swimming training periodization responses on aerobic and anaerobic performance, glycogen concentration in muscle (M and liver (L, and

  13. Efeitos do estresse agudo de contenção, do estresse crônico de natação e da administração de glutamina sobre a liberação de superóxido por macrófagos alveolares de ratos Effects of acute restraint stress, chronic swim stress and glutamine administration on the release of superoxide from alveolar macrophages of rats

    Directory of Open Access Journals (Sweden)

    Elizabeth do Nascimento

    2007-08-01

    Full Text Available OBJETIVO: Avaliar a liberação de ânion superóxido por macrófagos alveolares em ratos submetidos ou não ao estresse agudo, ao exercício físico de natação e à suplementação com glutamina. MÉTODOS: Quarenta e dois ratos machos da linhagem Wistar com idade em torno de 62 (desvio-padrão=3 dias de idade foram divididos em grupos controle, treino, estresse e glutamina. Após a intervenção, macrófagos alveolares foram coletados e estimulados com acetato de formol miristato para a avaliação da liberação de ânion superóxido. RESULTADOS: Em comparação à primeira hora (controle=26,2, desvio-padrão=4,2; treino=28,7, desvio-padrão=5,1; estresse=20,3, desvio-padrão=4,4; glutamina=26,2, desvio-padrão=4,2, houve aumento (pOBJECTIVE: To assess the release of superoxide anion from alveolar macrophages of rats submitted or not to acute restraint stress, forced swimming and glutamine supplementation. METHODS: Forty-two male Wistar rats aging roughly 62 days (standard deviation=3 were randomly divided into four groups: control, training, stress and glutamine. After the intervention, alveolar macrophages were collected and stimulated with phorbol myristate acetate to assess the release of superoxide anion. RESULTS: When compared with the first hour (control=26.2, standard deviation=4.2; training=28.7, standard deviation=5.1; stress=20.3 , standard deviation=4.4; glutamine=26.2, standard deviation=4.2, the release of superoxide increased (p<0.001 in all experimental groups in the second hour (control=38.4, standard deviation=4.9; training=40.7, standard deviation=6.1; stress=30.2, standard deviation=5.6; glutamine=39.2, standard deviation=5.2 of observation. Training and glutamine supplementation did not induce differences in the release of superoxide from alveolar macrophages when compared with the control group. Only the rats submitted to stress showed a reduction in the release of superoxide in both the first (20.3, standard deviation

  14. Numerical and experimental investigations of human swimming motions.

    Science.gov (United States)

    Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H

    2016-08-01

    This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer's potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m(2) area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency.

  15. Synergistic effect of estradiol and fluoxetine in young adult and middle-aged female rats in two models of experimental depression.

    Science.gov (United States)

    Récamier-Carballo, Soledad; Estrada-Camarena, Erika; Reyes, Rebeca; Fernández-Guasti, Alonso

    2012-08-01

    The antidepressant effect of estrogens combined with antidepressants is controversial: some preclinical data showed that estrogens facilitate the effect of antidepressants in the forced swimming test (FST) in young adult rats, while others failed to find such effect in middle-aged rats in the chronic mild stress (CMS) model. In clinics similar differences were reported and may be due to the compounds, the depression model or type of depression, the experimental design, and the age of the subjects or the women's menopause stage. The objective of this study was to analyze the antidepressant-like effect of the combination of 17β-estradiol (E(2)) and fluoxetine (FLX) in young adults (2-4 months) and middle-aged (12-14 months) ovariectomized (OVX) rats in two experimental models: FST and CMS. E(2) (5 and 10 μg/rat) and FLX (2.5 and 10 mg/kg) per se dose-dependently reduced immobility in both age groups and, in young adults both compounds increased swimming, whereas in middle-aged rats they increased swimming and climbing. Analysis of the antidepressant-like effect of the combination of suboptimal doses of FLX (1.25 mg/kg) and E(2) (2.5 μg/rat) showed a decrease in immobility and an increase in swimming in both age groups. In the CMS, chronic E(2) (2.5 μg/rat) with FLX (1.25 mg/kg) augmented relative sucrose intake, but middle-aged rats responded 2 weeks earlier than young adults. These results show that the antidepressant-like effect of the combination of E(2) and FLX in young adult and middle-aged female rats is evidenced in the two animal models of depression: FST and CMS. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Swimming and other activities: applied aspects of fish swimming performance

    Science.gov (United States)

    Castro-Santos, Theodore R.; Farrell, A.P.

    2011-01-01

    Human activities such as hydropower development, water withdrawals, and commercial fisheries often put fish species at risk. Engineered solutions designed to protect species or their life stages are frequently based on assumptions about swimming performance and behaviors. In many cases, however, the appropriate data to support these designs are either unavailable or misapplied. This article provides an overview of the state of knowledge of fish swimming performance – where the data come from and how they are applied – identifying both gaps in knowledge and common errors in application, with guidance on how to avoid repeating mistakes, as well as suggestions for further study.

  17. Alterations in the muscle force transfer apparatus in aged rats during unloading and reloading: Impact of microRNA-31.

    Science.gov (United States)

    Hughes, David C; Marcotte, George R; Baehr, Leslie M; West, Daniel W D; Marshall, Andrea G; Ebert, Scott M; Davidyan, Arik; Adams, Christopher M; Bodine, Sue C; Baar, Keith

    2018-05-03

    Force transfer is integral for maintaining skeletal muscle structure and function. One important component is dystrophin. There is limited understanding of how force transfer is impacted by age and loading. Here, we investigate the force transfer apparatus in muscles of adult and old rats exposed to periods of disuse and reloading. Our results demonstrate an increase in dystrophin protein during the reloading phase in the adult TA muscle that is delayed in old. The consequence of this delay is an increased susceptibility towards contraction-induced muscle injury. Central to the lack of dystrophin protein is an increase in miR-31, a microRNA that inhibits dystrophin translation. In vivo electroporation with a miR-31 sponge led to increased dystrophin protein and decreased contraction-induced muscle injury in old skeletal muscle. Overall, our results detail the importance of the force transfer apparatus and provide new mechanisms for contraction-induced injury in aging skeletal muscle. In healthy muscle, the dystrophin-associated glycoprotein (DGC) and integrin/focal adhesion complexes, intermediate filaments, and Z-line proteins transmit force from the contractile proteins to the extracellular matrix. How loading and age affect these proteins is poorly understood. The experiments reported here sought to determine the effect of aging on the force transfer apparatus following muscle unloading and reloading. Adult (9 months) and old (29 months) rats were subjected to 14 days hindlimb unloading (HU) and 1, 3, 7 and 14 days of reloading (REL). The DGC complex, intermediate filament and z-line protein and mRNA levels, as well as dystrophin-targeting miRNAs (miR-31, -146b and -374) were examined in the tibialis anterior (TA) and medial gastrocnemius (MG) muscles at both ages. There was a significant increase in dystrophin protein levels (2.79-fold) upon 3 days of reloading in the adult TA muscle that did not occur in the old rats (p ≤ 0.05), and the rise in

  18. Numerical study on the hydrodynamics of thunniform bio-inspired swimming under self-propulsion.

    Directory of Open Access Journals (Sweden)

    Ningyu Li

    Full Text Available Numerical simulations are employed to study the hydrodynamics of self-propelled thunniform swimming. The swimmer is modeled as a tuna-like flexible body undulating with kinematics of thunniform type. The wake evolution follows the vortex structures arranged nearly vertical to the forward direction, vortex dipole formation resulting in the propulsion motion, and finally a reverse Kármán vortex street. We also carry out a systematic parametric study of various aspects of the fluid dynamics behind the freely swimming behavior, including the swimming speed, hydrodynamic forces, power requirement and wake vortices. The present results show that the fin thrust as well as swimming velocity is an increasing function of both tail undulating amplitude Ap and oscillating amplitude of the caudal fin θm. Whereas change on the propulsive performance with Ap is associated with the strength of wake vortices and the area of suction region on the fin, the swimming performance improves with θm due to the favorable tilting of the fin that make the pressure difference force more oriented toward the thrust direction. Moreover, the energy loss in the transverse direction and the power requirement increase with Ap but decrease with θm, and this indicates that for achieving a desired swimming speed increasing θm seems more efficiently than increasing Ap. Furthermore, we have compared the current simulations with the published experimental studies on undulatory swimming. Comparisons show that our work tackles the flow regime of natural thunniform swimmers and follows the principal scaling law of undulatory locomotion reported. Finally, this study enables a detailed quantitative analysis, which is difficult to obtain by experiments, of the force production of the thunniform mode as well as its connection to the self-propelled swimming kinematics and vortex wake structure. The current findings help provide insights into the swimming performance and mechanisms of self

  19. Numerical study on the hydrodynamics of thunniform bio-inspired swimming under self-propulsion.

    Science.gov (United States)

    Li, Ningyu; Liu, Huanxing; Su, Yumin

    2017-01-01

    Numerical simulations are employed to study the hydrodynamics of self-propelled thunniform swimming. The swimmer is modeled as a tuna-like flexible body undulating with kinematics of thunniform type. The wake evolution follows the vortex structures arranged nearly vertical to the forward direction, vortex dipole formation resulting in the propulsion motion, and finally a reverse Kármán vortex street. We also carry out a systematic parametric study of various aspects of the fluid dynamics behind the freely swimming behavior, including the swimming speed, hydrodynamic forces, power requirement and wake vortices. The present results show that the fin thrust as well as swimming velocity is an increasing function of both tail undulating amplitude Ap and oscillating amplitude of the caudal fin θm. Whereas change on the propulsive performance with Ap is associated with the strength of wake vortices and the area of suction region on the fin, the swimming performance improves with θm due to the favorable tilting of the fin that make the pressure difference force more oriented toward the thrust direction. Moreover, the energy loss in the transverse direction and the power requirement increase with Ap but decrease with θm, and this indicates that for achieving a desired swimming speed increasing θm seems more efficiently than increasing Ap. Furthermore, we have compared the current simulations with the published experimental studies on undulatory swimming. Comparisons show that our work tackles the flow regime of natural thunniform swimmers and follows the principal scaling law of undulatory locomotion reported. Finally, this study enables a detailed quantitative analysis, which is difficult to obtain by experiments, of the force production of the thunniform mode as well as its connection to the self-propelled swimming kinematics and vortex wake structure. The current findings help provide insights into the swimming performance and mechanisms of self

  20. Resilience in shock and swim stress models of depression

    Directory of Open Access Journals (Sweden)

    Robert Charles Drugan

    2013-02-01

    Full Text Available Experimental models of depression often entail exposing a rodent to a stressor and subsequently characterizing changes in learning and anhedonia, which may reflect symptoms of human depression. Importantly, not all people and not all laboratory rats exposed to stressors develop depressed behavior; these resilient individuals are the focus of our review. Herein we describe research from the learned helplessness and intermittent swim stress models of depression in which rats that were allowed to cope with the stressor appear to be behaviorally and neurochemically similar to rats that were not allowed to cope yet appeared resilient in behavioral tests. For example, rats exposed to inescapable tailshock, but do not develop learned helplessness, exhibit altered sensitivity to the behavioral effects of GABAA receptor antagonists and reduced in vitro benzodiazepine receptor ligand binding. This pattern suggested that resilience might involve activation of an endogenous benzodiazepine-like compound, possibly an allostatic modulator of the GABAA receptor like allopregnanolone. From the intermittent swim stress model, we have observed in resilient rats protection from stressor-induced glucocorticoid increases and immune activation. In order to identify the neural mediators of these correlates of resilience, non-invasive measures are needed to predict the resilient or vulnerable phenotype prior to analysis of neural endpoints. To this end, we found that ultrasonic vocalizations (USVs appear to predict the resilient phenotype in the intermittent swim stress paradigm. We propose that combining non-invasive predictive measures, such as USVs with biological endpoint measures, will facilitate future research into the neural correlates of resilience.

  1. Orthodontic Forces Induce the Cytoprotective Enzyme Heme Oxygenase-1 in Rats

    NARCIS (Netherlands)

    Suttorp, C.M.; Xie, R.; Lundvig, D.M.S.; Kuijpers-Jagtman, A.M.; Uijttenboogaart, J.T.; Rheden, R.E.M. van; Maltha, J.C.; Wagener, F.A.D.T.G.

    2016-01-01

    Orthodontic forces disturb the microenvironment of the periodontal ligament (PDL), and induce craniofacial bone remodeling which is necessary for tooth movement. Unfortunately, orthodontic tooth movement is often hampered by ischemic injury and cell death within the PDL (hyalinization) and root

  2. Water Evaporation in Swimming Baths

    DEFF Research Database (Denmark)

    Hyldgård, Carl-Erik

    This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which are repres......This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which...... are represented in instructions for carrying out and running swimming baths. If you follow the instructions you can achieve less investments, less heat consumption and a better comfort to the bathers....

  3. Paramecium swimming in capillary tube

    Science.gov (United States)

    Jana, Saikat; Um, Soong Ho; Jung, Sunghwan

    2012-04-01

    Swimming organisms in their natural habitat need to navigate through a wide range of geometries and chemical environments. Interaction with boundaries in such situations is ubiquitous and can significantly modify the swimming characteristics of the organism when compared to ideal laboratory conditions. We study the different patterns of ciliary locomotion in glass capillaries of varying diameter and characterize the effect of the solid boundaries on the velocities of the organism. Experimental observations show that Paramecium executes helical trajectories that slowly transition to straight lines as the diameter of the capillary tubes decreases. We predict the swimming velocity in capillaries by modeling the system as a confined cylinder propagating longitudinal metachronal waves that create a finite pressure gradient. Comparing with experiments, we find that such pressure gradient considerations are necessary for modeling finite sized ciliary organisms in restrictive geometries.

  4. Optimal swimming of a sheet.

    Science.gov (United States)

    Montenegro-Johnson, Thomas D; Lauga, Eric

    2014-06-01

    Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

  5. Swimming in an Unsteady World

    Science.gov (United States)

    Koehl, M. A. R.

    2016-02-01

    When animals swim in marine habitats, the water through which they move is usually flowing. Therefore, an important part of understanding the physics of how animals swim in nature is determining how they interact with the fluctuating turbulent water currents in their environment. The research systems we have been using to address this question are microscopic marine animals swimming in turbulent, wavy water flow over spatially-complex communities of organisms growing on surfaces. Field measurements of water motion were used to design realistic turbulent flow in a laboratory wave-flume over different substrata, particle-image velocimetry was used to measure fine-scale, rapidly-varying water velocity vector fields, and planar laser-induced fluorescence was used to measure concentrations of chemical cues from the substratum. We used individual-based models of small animals swimming in this unsteady flow to determine how their trajectories and contacts with substrata were affected by their locomotion through the water, rotation by local shear, response to odors, and transport by ambient flow. We found that the shears, accelerations, and odor concentrations encountered by small swimmers fluctuate rapidly, with peaks much higher than mean values lasting fractions of a second. We identified ways in which the behavior of small, weak swimmers can bias how they are transported by ambient flow (e.g. sinking during brief encounters with shear or odor enhances settlement onto substrata below, whereas constant swimming enhances contact with surfaces above or beside larvae). Although microscopic organisms swim slowly relative to ambient water flow, their locomotory behavior in response to the rapidly-fluctuating shears and odors they encounter can affect where they are transported by ambient water movement.

  6. Resident intruder paradigm-induced aggression relieves depressive-like behaviors in male rats subjected to chronic mild stress

    Science.gov (United States)

    Wei, Sheng; Ji, Xiao-wei; Wu, Chun-ling; Li, Zi-fa; Sun, Peng; Wang, Jie-qiong; Zhao, Qi-tao; Gao, Jie; Guo, Ying-hui; Sun, Shi-guang; Qiao, Ming-qi

    2014-01-01

    Background Accumulating epidemiological evidence shows that life event stressors are major vulnerability factors for psychiatric diseases such as major depression. It is also well known that the resident intruder paradigm (RIP) results in aggressive behavior in male rats. However, it is not known how resident intruder paradigm-induced aggression affects depressive-like behavior in isolated male rats subjected to chronic mild stress (CMS), which is an animal model of depression. Material/Methods Male Wistar rats were divided into 3 groups: non-stressed controls, isolated rats subjected to the CMS protocol, and resident intruder paradigm-exposed rats subjected to the CMS protocol. Results In the sucrose intake test, ingestion of a 1% sucrose solution by rats in the CMS group was significantly lower than in control and CMS+RIP rats after 3 weeks of stress. In the open-field test, CMS rats had significantly lower open-field scores compared to control rats. Furthermore, the total scores given the CMS group were significantly lower than in the CMS+RIP rats. In the forced swimming test (FST), the immobility times of CMS rats were significantly longer than those of the control or CMS+RIP rats. However, no differences were observed between controls and CMS+RIP rats. Conclusions Our data show that aggressive behavior evoked by the resident intruder paradigm could relieve broad-spectrum depressive-like behaviors in isolated adult male rats subjected to CMS. PMID:24911067

  7. Surface Waters Information Management System (SWIMS)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Surface Waters Information Management System (SWIMS) has been designed to meet multi-agency hydrologic database needs for Kansas. The SWIMS project was supported...

  8. Morphometric evaluation of condylar cartilage of growing rats in response to mandibular retractive forces

    Directory of Open Access Journals (Sweden)

    Milena Peixoto Nogueira de Sá

    2013-08-01

    Full Text Available INTRODUCTION: The mandibular condylar surface is made up of four layers, i.e., an external layer composed of dense connective tissue, followed by a layer of undifferentiated cells, hyaline cartilage and bone. Few studies have demonstrated the behavior of the condylar cartilage when the mandible is positioned posteriorly, as in treatments for correcting functional Class III malocclusion. OBJECTIVE: The aim of this study was to assess the morphologic and histological aspects of rat condyles in response to posterior positioning of the mandible. METHODS: Thirty five-week-old male Wistar rats were selected and randomly divided into two groups: A control group (C and an experimental group (E which received devices for inducing mandibular retrusion. The animals were euthanized at time intervals of 7, 21 and 30 days after the experiment had began. For histological analysis, total condylar thickness was measured, including the proliferative, hyaline and hypertrophic layers, as well as each layer separately, totaling 30 measurements for each parameter of each animal. RESULTS: The greatest difference in cartilage thickness was observed in 21 days, although different levels were observed in the other periods. Group E showed an increase of 39.46% in the total layer, reflected by increases in the thickness of the hypertrophic (42.24%, hyaline (46.92% and proliferative (17.70% layers. CONCLUSIONS: Posteriorly repositioning the mandible produced a series of histological and morphological responses in the condyle, suggesting condylar and mandibular adaptation in rats.

  9. Morphometric evaluation of condylar cartilage of growing rats in response to mandibular retractive forces.

    Science.gov (United States)

    de Sá, Milena Peixoto Nogueira; Zanoni, Jacqueline Nelisis; de Salles, Carlos Luiz Fernandes; de Souza, Fabrício Dias; Suga, Uhana Seifert Guimarães; Terada, Raquel Sano Suga

    2013-01-01

    The mandibular condylar surface is made up of four layers, i.e., an external layer composed of dense connective tissue, followed by a layer of undifferentiated cells, hyaline cartilage and bone. Few studies have demonstrated the behavior of the condylar cartilage when the mandible is positioned posteriorly, as in treatments for correcting functional Class III malocclusion. The aim of this study was to assess the morphologic and histological aspects of rat condyles in response to posterior positioning of the mandible. Thirty five-week-old male Wistar rats were selected and randomly divided into two groups: A control group (C) and an experimental group (E) which received devices for inducing mandibular retrusion. The animals were euthanized at time intervals of 7, 21 and 30 days after the experiment had began. For histological analysis, total condylar thickness was measured, including the proliferative, hyaline and hypertrophic layers, as well as each layer separately, totaling 30 measurements for each parameter of each animal. The greatest difference in cartilage thickness was observed in 21 days, although different levels were observed in the other periods. Group E showed an increase of 39.46% in the total layer, reflected by increases in the thickness of the hypertrophic (42.24%), hyaline (46.92%) and proliferative (17.70%) layers. Posteriorly repositioning the mandible produced a series of histological and morphological responses in the condyle, suggesting condylar and mandibular adaptation in rats.

  10. The effect of external dummy transmitters on oxygen consumption and performance of swimming Atlantic cod

    DEFF Research Database (Denmark)

    Steinhausen, M.F.; Andersen, Niels Gerner; Steffensen, J.F.

    2006-01-01

    Decreased critical swimming speed and increased oxygen consumption (Mo-2) was found for externally tagged Atlantic cod Gadus morhua swimming at a high speed of 0 center dot 9 body length (total length, L-Gamma) s(-1). No difference was found in the standard metabolic rate, indicating...... that the higher Mo-2 for tagged cod was due to drag force rather than increased costs to keep buoyancy. (c) 2006 The Authors Journal compilation (c) 2006 The Fisheries Society of the British Isles....

  11. Development of a Simulation Model for Swimming with Diving Fins

    Directory of Open Access Journals (Sweden)

    Motomu Nakashima

    2018-02-01

    Full Text Available The simulation model to assess the performance of diving fin was developed by extending the swimming human simulation model SWUM. A diving fin was modeled as a series of five rigid plates and connected to the human model by springs and dampers. These plates were connected to each other by virtual springs and dampers, and fin’s bending property was represented by springs and dampers as well. An actual diver’s swimming motion with fins was acquired by a motion capture experiment. In order to determine the bending property of the fin, two bending tests on land were conducted. In addition, an experiment was conducted in order to determine the fluid force coefficients in the fluid force model for the fin. Finally, using all measured and identified information, a simulation, in which the experimental situation was reproduced, was carried out. It was confirmed that the diver in the simulation propelled forward in the water successfully.

  12. 43 CFR 423.36 - Swimming.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Swimming. 423.36 Section 423.36 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR... Swimming. (a) You may swim, wade, snorkel, scuba dive, raft, or tube at your own risk in Reclamation waters...

  13. 36 CFR 331.10 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 331.10 Section 331.10 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY REGULATIONS..., KENTUCKY AND INDIANA § 331.10 Swimming. Swimming is prohibited unless authorized in writing by the District...

  14. 36 CFR 327.5 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 327.5 Section 327.5 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY RULES AND REGULATIONS... Swimming. (a) Swimming, wading, snorkeling or scuba diving at one's own risk is permitted, except at...

  15. 1968 Listing of Swimming Pool Equipment.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

    An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

  16. Undulatory fish swimming : from muscles to flow

    NARCIS (Netherlands)

    Müller, U.K.; Leeuwen, van J.L.

    2006-01-01

    Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish's axial muscles power swimming; and (ii) how the fish's body and fins generate thrust. Fish have adapted the morphology of their axial

  17. Effect of Short-term Forced Exercise on Naloxone Induced Withdrawal Symptoms in Morphine Addicted Male Rats

    Directory of Open Access Journals (Sweden)

    KH Saadipour

    2008-01-01

    Full Text Available ABSTRACT: Introduction & Objective: Opioid dependence has been causing limitation in usage of morphine and other opioid drugs in pain control. The aim of this study was to assess the effect of short-term forced exercise on withdrawal syndrome in morphine addicted male rats. Materials & Methods: This experimental study was done in the physiology research center of Ahwas Jondishapour University of Medical Sciences. Twenty four young male Wistar rats, weighing 200-300gr, were randomly divided into four groups: no addiction and no exercise, no addiction and exercise, addiction and no exercise and addiction and exercise. The exercise groups underwent treadmill forced exercise for ten days. The first five days morphine was administrated (ip twice daily with increasing dose (5، 10، 20، 40, 50 mg/kg to addicted groups. Also single dose (50mg/kg of morphine was administrated to them on the 10th day of exercise. After administration of naloxone hydrochloride the withdrawal symptoms were evaluated for 5 minutes. The findings of this study were analyzed by SPSS software and One- way ANOVA (Tukey test. Results: The findings of this study showed that the withdrawal symptoms was elevated in exercise and addicted groups in comparison with control group (p<0.05 , p<0.01. However, most of withdrawal symptoms decreased in addicted and exercise group in comparison with addicted and no exercise group (p<0.01, p<0.001. Conclusion: The exercise could increase endogenous opioid and withdrawal symptoms in animals but reduce withdrawal symptoms in addicted and exercise groups compared to addicted and no exercise group. Its mechanism might be related to down regulation and low sensitivity of opioid receptors

  18. The influence of elements of synchronized swimming on technique of the selected swimming strokes

    OpenAIRE

    Široký, Michal

    2015-01-01

    Title: The influence of elements of synchronized swimming on technique of the selected swimming strokes Objectives: The objective of the thesis is to assess the effect of the elements of synchronized swimming at improving the techniques of swimming. Methods: The results were detected by overt observation with active participation and subsequent scaling on the ordinal scale 1 to 5. Results: The results show that the influence of the elements of synchronized swimming on improving the technique ...

  19. Impaired swimming performance of acid-exposed Arctic charr, Salvelinus alpinus L

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, L.A. (North/South Consultants Inc., Winnipeg, MB (Canada)); Scherer, E. (Dept. of Fisheries and Oceans, Freshwater Inst. Science Lab., Winnipeg, MB (Canada))

    1988-01-01

    Effects of increased ambient acidity are of particular interest, as the formation of metabolic and respiratory acids and acceleration of branchial ion loss during vigorous swimming duplicates or compounds effects of exposure to environmental acidity. Three year old Arctic charr (Salvelinus alpinus L.) were exposed to five levels of acidity between pH 6 and pH 3.8. Swimming performance as determined by critical swimming speeds was 67.5 cm {center dot} s{sup -1} or 4.4 body lengths per second for untreated fish (pH 7.8). Performance declined sharply below pH 4.5; at pH 3.8 it was reduced by 35% after 7 days of exposure. Tailbeat frequencies and ventilation rates showed no dose-response effects. This would support the assumption that afferent and efferent neuromuscular functions may have remained unimpaired under increased ambient acidity so that the stimulus of directed water current continued to elicit forced swimming, causing (forcing) the fish to use the entire scope for activity available at the various pH levels. At swimming speeds between 20 and 50 cm {center dot} s{sup -1}, ventilation rates at all levels of acidity were higher than at the control level. Based on this, spontaneous, i.e., non-forced swimming activity may show a lower response threshold. 19 refs., 3 figs., 1 tab.

  20. Análise do significado do tempo de imobilidade em modelos experimentais de natação Analysis of the meaning of the immobility time in swimming experimental models

    Directory of Open Access Journals (Sweden)

    Caroline Morini Calil

    2002-12-01

    Full Text Available O objetivo do trabalho foi testar a hipótese de que a interpretação do tempo de imobilidade (desamparo aprendido ou adaptação pode variar conforme o modelo utilizado (teste da natação forçada ou estresse por natação. Foram analisados o tempo de imobilidade (TI e a mobilização de glicogênio de ratos submetidos à natação em dois protocolos: estresse por natação (EN e teste da natação forçada (TNF. Também comparamos os efeitos da desipramina e diazepam. Os experimentos foram filmados para análise do TI. Os ratos, após a sessão de natação, foram sacrificados e amostras do fígado e músculos foram preparadas para quantificação do glicogênio. O TI foi menor no EN comparado ao TNF (p=0,001. As concentrações de glicogênio hepático dos grupos foram diferentes entre si (controle>EN>TNF; pThe aim of this work was to evaluate if the meaning of immobility (helplessness or adaptation depends on the experimental model (forced swimming test or swimming stress. Immobility time (IT and glycogen mobilization of rats submitted to swimming session were analyzed in two protocols: swimming stress (SS and forced swimming test (FST. We also compared the effects of desipramine and diazepam. The experiments were recorded to evaluate the IT. The rats, after swimming session, were sacrificed and hepatic and muscles samples were prepared to the quantification of glycogen. IT was lower in SS than in FST (p=0.001. Hepatic glycogen concentration were different one from another (control>FST>SS;p<0.05. The glycogen concentrations at gastrocnemius and soleus muscles were lower at SS compared to FST and control (p<0.05. The IT was recorded and measured from another group treated with desipramine and diazepam. Desipramine decreased the IT in the FST but not in the SS. Diazepam increased the IT in the SS but not in the FST. We conclude that SS and FST induced different physiological and behavioral responses and represent different situations for the

  1. Fluid Mechanics of Fish Swimming

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 1. Fluid Mechanics of Fish Swimming - Lift-based Propulsion. Jaywant H Arakeri. General Article Volume 14 Issue 1 January 2009 pp 32-46. Fulltext. Click here to view fulltext PDF. Permanent link:

  2. Sodium bicarbonate improves swimming performance.

    Science.gov (United States)

    Lindh, A M; Peyrebrune, M C; Ingham, S A; Bailey, D M; Folland, J P

    2008-06-01

    Sodium bicarbonate ingestion has been shown to improve performance in single-bout, high intensity events, probably due to an increase in buffering capacity, but its influence on single-bout swimming performance has not been investigated. The effects of sodium bicarbonate supplementation on 200 m freestyle swimming performance were investigated in elite male competitors. Following a randomised, double blind counterbalanced design, 9 swimmers completed maximal effort swims on 3 separate occasions: a control trial (C); after ingestion of sodium bicarbonate (SB: NaHCO3 300 mg . kg (-1) body mass); and after ingestion of a placebo (P: CaCO3 200 mg . kg (-1) body mass). The SB and P agents were packed in gelatine capsules and ingested 90 - 60 min prior to each 200 m swim. Mean 200 m performance times were significantly faster for SB than C or P (1 : 52.2 +/- 4.7; 1 : 53.7 +/- 3.8; 1 : 54.0 +/- 3.6 min : ss; p bicarbonate were all elevated pre-exercise in the SB compared to C and P trials (p < 0.05). Post-200 m blood lactate concentrations were significantly higher following the SB trial compared with P and C (p < 0.05). It was concluded that SB supplementation can improve 200 m freestyle performance time in elite male competitors, most likely by increasing buffering capacity.

  3. Shape Optimization of Swimming Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  4. Swimming and Persons with Mild Persistant Asthma

    Directory of Open Access Journals (Sweden)

    Mirjana Arandelovic

    2007-01-01

    Full Text Available The aim of our study was to analyze the effect of recreational swimming on lung function and bronchial hyperresponsiveness (BHR in patients with mild persistent asthma. This study included 65 patients with mild persistent asthma, who were divided into two groups: experimental group A (n = 45 and control group B (n = 20. Patients from both groups were treated with low doses of inhaled corticosteroids (ICS and short-acting β2 agonists salbutamol as needed. Our program for patients in group A was combined asthma education with swimming (twice a week on a 1-h basis for the following 6 months. At the end of the study, in Group A, we found a statistically significant increase of lung function parameters FEV1 (forced expiratory volume in 1 sec (3.55 vs. 3.65 (p < 0.01, FVC (forced vital capacity (4.27 vs. 4.37 (p < 0.05, PEF (peak expiratory flow (7.08 vs. 7.46 (p < 0.01, and statistically significant decrease of BHR (PD20 0.58 vs. 2.01 (p < 0.001. In Group B, there was a statistically significant improvement of FEV1 3.29 vs. 3.33 (p < 0.05 and although FVC, FEV1/FVC, and PEF were improved, it was not significant. When Groups A and B were compared at the end of the study, there was a statistically significant difference of FVC (4.01 vs. 4.37, FEV1 (3.33 vs. 3.55, PEF (6.79 vs.7.46, and variability (p <0.001, and statistically significantly decreased BHR in Group A (2.01 vs. 1.75 (p < 0.001. Engagement of patients with mild persistent asthma in recreational swimming in nonchlorinated pools, combined with regular medical treatment and education, leads to better improvement of their parameters of lung function and also to more significant decrease of their airway hyperresponsiveness compared to patients treated with traditional medicine

  5. CHARACTER OF THE CHANGES IN FEAR MOTIVATED DECLARATIVE MEMORY IN THE HIGH IMMOBILIZATION "DEPRESSIVE" RATS.

    Science.gov (United States)

    Nachkebia, N; Shavgulidze, M; Babilodze, M; Chkhartishvili, E; Rogava, N

    2016-10-01

    Present study investigated possible differences in the learning and memory of declarative memory task in rats selected according to the differences in immobilization response that is in high immobilization "depressive" and low immobilization "non-depressive" rats. Understanding the character of learning and memory disturbances in basal conditions of animal models of depression is still very topical for more intimate definition of the pathophysiology of major depressive disorder and appropriate searching the ways of its correction. Experiments were carried out on the adult white wild rats (with the weight 200-250 g, n=20). Selection of rats according to the level of immobilization was made by means of forced swim test. Learning and memory disturbances were studied using passive avoidance test that is fear motivated one trial declarative memory task. It was shown by us that 100% of low immobilization "non-depressive" rats remember painful stimulation and therefore they are not enter in the dark compartment during whole period of observation during testing session. Behavior of high immobilization "depressive" rats is not similar in passive avoidance camera; 50% of "depressive" rats, with long escape latency during training session (92±10 sec), remember painful stimulation during testing session and therefore they are not enter in the dark compartment during whole observation period. The remaining 50%, that are not differ significantly from the low immobility "non-depressive" rats by the latency of escape (5±1 sec) during training session, are not able to remember painful stimulation during testing session and therefore they enter in the dark compartment with shortest escape latency (6±1 sec). In conclusion, high immobility "depressive" rats perform passive avoidance declarative memory task at the chance level that is a direct indicator for the serious disturbances of declarative memory mechanisms in "depressive" rats selected in forced swim test according to the

  6. Possible involvement of neuropeptide Y Y1 receptors in antidepressant like effect of agmatine in rats.

    Science.gov (United States)

    Kotagale, Nandkishor R; Paliwal, Nikhilesh P; Aglawe, Manish M; Umekar, Milind J; Taksande, Brijesh G

    2013-09-01

    Agmatine and neuropeptide Y (NPY) are widely distributed in central nervous system and critically involved in modulation of depressive behavior in experimental animals. However their mutual interaction, if any, in regulation of depression remain largely unexplored. In the present study we explored the possible interaction between agmatine and neuropeptide Y in regulation of depression like behavior in forced swim test. We found that acute intracerebroventricular (i.c.v.) administration of agmatine (20-40μg/rat), NPY (5 and 10μg/rat) and NPY Y1 receptor agonist, [Leu(31), Pro(34)]-NPY (0.4 and 0.8ng/rat) dose dependently decreased immobility time in forced swim test indicating their antidepressant like effects. In combination studies, the antidepressant like effect of agmatine (10μg/rat) was significantly potentiated by NPY (1 and 5μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2 and 0.4ng/rat, icv) pretreatment. Conversely, pretreatment of animals with NPY Y1 receptor antagonist, BIBP3226 (0.1ng/rat, i.c.v.) completely blocked the antidepressant like effect of agmatine (20-40μg/rat) and its synergistic effect with NPY (1μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2ng/rat, icv). The results of the present study showed that, agmatine exerts antidepressant like effects via NPYergic system possibly mediated by the NPY Y1 receptor subtypes and suggest that interaction between agmatine and neuropeptide Y may be relevant to generate the therapeutic strategies for the treatment of depression. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Relative Contribution of Arms and Legs in 30 s Fully Tethered Front Crawl Swimming

    Directory of Open Access Journals (Sweden)

    Pedro G. Morouço

    2015-01-01

    Full Text Available The relative contribution of arm stroke and leg kicking to maximal fully tethered front crawl swimming performance remains to be solved. Twenty-three national level young swimmers (12 male and 11 female randomly performed 3 bouts of 30 s fully tethered swimming (using the whole body, only the arm stroke, and only the leg kicking. A load-cell system permitted the continuous measurement of the exerted forces, and swimming velocity was calculated from the time taken to complete a 50 m front crawl swim. As expected, with no restrictions swimmers were able to exert higher forces than that using only their arm stroke or leg kicking. Estimated relative contributions of arm stroke and leg kicking were 70.3% versus 29.7% for males and 66.6% versus 33.4% for females, with 15.6% and 13.1% force deficits, respectively. To obtain higher velocities, male swimmers are highly dependent on the maximum forces they can exert with the arm stroke (r=0.77, P<0.01, whereas female swimmers swimming velocity is more related to whole-body mean forces (r=0.81, P<0.01. The obtained results point that leg kicking plays an important role over short duration high intensity bouts and that the used methodology may be useful to identify strength and/or coordination flaws.

  8. The effects of voluntary, involuntary, and forced exercises on brain-derived neurotrophic factor and motor function recovery: a rat brain ischemia model.

    Directory of Open Access Journals (Sweden)

    Zheng Ke

    Full Text Available BACKGROUND: Stroke rehabilitation with different exercise paradigms has been investigated, but which one is more effective in facilitating motor recovery and up-regulating brain neurotrophic factor (BDNF after brain ischemia would be interesting to clinicians and patients. Voluntary exercise, forced exercise, and involuntary muscle movement caused by functional electrical stimulation (FES have been individually demonstrated effective as stroke rehabilitation intervention. The aim of this study was to investigate the effects of these three common interventions on brain BDNF changes and motor recovery levels using a rat ischemic stroke model. METHODOLOGY/PRINCIPAL FINDINGS: One hundred and seventeen Sprague-Dawley rats were randomly distributed into four groups: Control (Con, Voluntary exercise of wheel running (V-Ex, Forced exercise of treadmill running (F-Ex, and Involuntary exercise of FES (I-Ex with implanted electrodes placed in two hind limb muscles on the affected side to mimic gait-like walking pattern during stimulation. Ischemic stroke was induced in all rats with the middle cerebral artery occlusion/reperfusion model and fifty-seven rats had motor deficits after stroke. Twenty-four hours after reperfusion, rats were arranged to their intervention programs. De Ryck's behavioral test was conducted daily during the 7-day intervention as an evaluation tool of motor recovery. Serum corticosterone concentration and BDNF levels in the hippocampus, striatum, and cortex were measured after the rats were sacrificed. V-Ex had significantly better motor recovery in the behavioral test. V-Ex also had significantly higher hippocampal BDNF concentration than F-Ex and Con. F-Ex had significantly higher serum corticosterone level than other groups. CONCLUSION/SIGNIFICANCE: Voluntary exercise is the most effective intervention in upregulating the hippocampal BDNF level, and facilitating motor recovery. Rats that exercised voluntarily also showed less

  9. Application of a rat hindlimb model: a prediction of force spaces reachable through stimulation of nerve fascicles.

    Science.gov (United States)

    Johnson, Will L; Jindrich, Devin L; Zhong, Hui; Roy, Roland R; Edgerton, V Reggie

    2011-12-01

    A device to generate standing or locomotion through chronically placed electrodes has not been fully developed due in part to limitations of clinical experimentation and the high number of muscle activation inputs of the leg. We investigated the feasibility of functional electrical stimulation paradigms that minimize the input dimensions for controlling the limbs by stimulating at nerve fascicles, utilizing a model of the rat hindlimb, which combined previously collected morphological data with muscle physiological parameters presented herein. As validation of the model, we investigated the suitability of a lumped-parameter model for the prediction of muscle activation during dynamic tasks. Using the validated model, we found that the space of forces producible through activation of muscle groups sharing common nerve fascicles was nonlinearly dependent on the number of discrete muscle groups that could be individually activated (equivalently, the neuroanatomical level of activation). Seven commonly innervated muscle groups were sufficient to produce 78% of the force space producible through individual activation of the 42 modeled hindlimb muscles. This novel, neuroanatomically derived reduction in input dimension emphasizes the potential to simplify controllers for functional electrical stimulation to improve functional recovery after a neuromuscular injury.

  10. Reactive oxygen species and fatigue-induced prolonged low-frequency force depression in skeletal muscle fibres of rats, mice and SOD2 overexpressing mice.

    Science.gov (United States)

    Bruton, Joseph D; Place, Nicolas; Yamada, Takashi; Silva, José P; Andrade, Francisco H; Dahlstedt, Anders J; Zhang, Shi-Jin; Katz, Abram; Larsson, Nils-Göran; Westerblad, Håkan

    2008-01-01

    Skeletal muscle often shows a delayed force recovery after fatiguing stimulation, especially at low stimulation frequencies. In this study we focus on the role of reactive oxygen species (ROS) in this fatigue-induced prolonged low-frequency force depression. Intact, single muscle fibres were dissected from flexor digitorum brevis (FDB) muscles of rats and wild-type and superoxide dismutase 2 (SOD2) overexpressing mice. Force and myoplasmic free [Ca(2+)] ([Ca(2+)](i)) were measured. Fibres were stimulated at different frequencies before and 30 min after fatigue induced by repeated tetani. The results show a marked force decrease at low stimulation frequencies 30 min after fatiguing stimulation in all fibres. This decrease was associated with reduced tetanic [Ca(2+)](i) in wild-type mouse fibres, whereas rat fibres and mouse SOD2 overexpressing fibres instead displayed a decreased myofibrillar Ca(2+) sensitivity. The SOD activity was approximately 50% lower in wild-type mouse than in rat FDB muscles. Myoplasmic ROS increased during repeated tetanic stimulation in rat fibres but not in wild-type mouse fibres. The decreased Ca(2+) sensitivity in rat fibres could be partially reversed by application of the reducing agent dithiothreitol, whereas the decrease in tetanic [Ca(2+)](i) in wild-type mouse fibres was not affected by dithiothreitol or the antioxidant N-acetylcysteine. In conclusion, we describe two different causes of fatigue-induced prolonged low-frequency force depression, which correlate to differences in SOD activity and ROS metabolism. These findings may have clinical implications since ROS-mediated impairments in myofibrillar function can be counteracted by reductants and antioxidants, whereas changes in SR Ca(2+) handling appear more resistant to interventions.

  11. Behavioural profiles of two Wistar rat lines selectively bred for high or low anxiety-related behaviour.

    Science.gov (United States)

    Liebsch, G; Montkowski, A; Holsboer, F; Landgraf, R

    1998-08-01

    Over the past years, two breeding lines, derived originally from outbred Wistar rats, have been established that differ markedly and consistently in their anxiety-related behaviour in the elevated plus-maze. At the age of ten weeks, rats were tested once on the elevated plus-maze and the males and females displaying the most anxious and the least anxious behaviour were sib-mated to start a new generation of the high anxiety-related behaviour (HAB) and the low anxiety-related behaviour (LAB) lines, respectively. The resulting difference in emotionality between these two lines was also evident in an open field test and correlated with differences in the forced swim test. In the open field, the HAB rats tended to be less active and explored the central zone of the open field much less than the LAB animals. In the forced swim test, HAB rats started floating earlier, spent significantly more time in this immobile posture and struggled less than LAB rats. However, in an olfactory-cued social discrimination task there was no difference between male and female animals from either line. The overall performance in these various behavioural tests suggests that selective breeding has resulted in rat lines not only differing markedly in their innate anxiety-related behaviour in the plus-maze, but also in other stress-related behavioural performances, suggesting a close link between the emotional evaluation of a novel and stre