Manipulation of dopamine metabolism contributes to attenuating innate high locomotor activity in ICR mice.

Science.gov (United States)

Yamaguchi, Takeshi; Nagasawa, Mao; Ikeda, Hiromi; Kodaira, Momoko; Minaminaka, Kimie; Chowdhury, Vishwajit S; Yasuo, Shinobu; Furuse, Mitsuhiro

2017-06-15

Attention-deficit hyperactivity disorder (ADHD) is defined as attention deficiency, restlessness and distraction. The main characteristics of ADHD are hyperactivity, impulsiveness and carelessness. There is a possibility that these abnormal behaviors, in particular hyperactivity, are derived from abnormal dopamine (DA) neurotransmission. To elucidate the mechanism of high locomotor activity, the relationship between innate activity levels and brain monoamines and amino acids was investigated in this study. Differences in locomotor activity between ICR, C57BL/6J and CBA/N mice were determined using the open field test. Among the three strains, ICR mice showed the greatest amount of locomotor activity. The level of striatal and cerebellar DA was lower in ICR mice than in C57BL/6J mice, while the level of L-tyrosine (L-Tyr), a DA precursor, was higher in ICR mice. These results suggest that the metabolic conversion of L-Tyr to DA is lower in ICR mice than it is in C57BL/6J mice. Next, the effects of intraperitoneal injection of (6R)-5, 6, 7, 8-tetrahydro-l-biopterin dihydrochloride (BH 4 ) (a co-enzyme for tyrosine hydroxylase) and L-3,4-dihydroxyphenylalanine (L-DOPA) on DA metabolism and behavior in ICR mice were investigated. The DA level in the brain was increased by BH 4 administration, but the increased DA did not influence behavior. However, L-DOPA administration drastically lowered locomotor activity and increased DA concentration in several parts of the brain. The reduced locomotor activity may have been a consequence of the overproduction of DA. In conclusion, the high level of locomotor activity in ICR mice may be explained by a strain-specific DA metabolism. Copyright © 2017 Elsevier B.V. All rights reserved.

The Effects of Sex-Ratio and Density on Locomotor Activity in the House Fly, Musca domestica

OpenAIRE

Bahrndorff, Simon; Kjærsgaard, Anders; Pertoldi, Cino; Loeschcke, Volker; Schou, Toke M.; Skovgård, Henrik; Hald, Birthe

2012-01-01

Although locomotor activity is involved in almost all behavioral traits, there is a lack of knowledge on what factors affect it. This study examined the effects of sex-ratio and density on the circadian rhythm of locomotor activity of adult Musca domestica L. (Diptera: Muscidae) using an infra-red light system. Sex-ratio significantly affected locomotor activity, increasing with the percentage of males in the vials. In accordance with other studies, males were more active than females, but th...

Influence of temperature on daily locomotor activity in the crab Uca pugilator.

Directory of Open Access Journals (Sweden)

Audrey M Mat

Full Text Available Animals living in the intertidal zone are exposed to prominent temperature changes. To cope with the energetic demands of environmental thermal challenges, ectotherms rely mainly on behavioral responses, which may change depending on the time of the day and seasonally. Here, we analyze how temperature shapes crabs' behavior at 2 different times of the year and show that a transition from constant cold (13.5°C to constant warm (17.5°C water temperature leads to increased locomotor activity levels throughout the day in fiddler crabs (Uca pugilator collected during the summer. In contrast, the same transition in environmental temperature leads to a decrease in the amplitude of the daily locomotor activity rhythm in crabs collected during the winter. In other words, colder temperatures during the cold season favor a more prominent diurnal behavior. We interpret this winter-summer difference in the response of daily locomotor activity to temperature changes within the framework of the circadian thermoenergetics hypothesis, which predicts that a less favorable energetic balance would promote a more diurnal activity pattern. During the winter, when the energetic balance is likely less favorable, crabs would save energy by being more active during the expected high-temperature phase of the day-light phase-and less during the expected low-temperature phase of the day-dark phase. Our results suggest that endogenous rhythms in intertidal ectotherms generate adaptive behavioral programs to cope with thermoregulatory demands of the intertidal habitat.

Decrease of GSK3β phosphorylation in the rat nucleus accumbens core enhances cocaine-induced hyper-locomotor activity.

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Kim, Wha Y; Jang, Ju K; Lee, Jung W; Jang, Hyunduk; Kim, Jeong-Hoon

2013-06-01

Glycogen synthase kinase 3β (GSK3β), which is abundantly present in the brain, is known to contribute to psychomotor stimulant-induced locomotor behaviors. However, most studies have been focused in showing that GSK3β is able to attenuate psychomotor stimulants-induced hyperactivity by increasing its phosphorylation levels in the nucleus accumbens (NAcc). So, here we examined in the opposite direction about the effects of decreased phosphorylation of GSK3β in the NAcc core on both basal and cocaine-induced locomotor activity by a bilateral microinjection into this site of an artificially synthesized peptide, S9 (0.5 or 5.0 μg/μL), which contains sequences around N-terminal serine 9 residue of GSK3β. We found that decreased levels of GSK3β phosphorylation in the NAcc core enhance cocaine-induced hyper-locomotor activity, while leaving basal locomotor activity unchanged. This is the first demonstration, to our knowledge, that the selective decrease of GSK3β phosphorylation levels in the NAcc core may contribute positively to cocaine-induced locomotor activity, while this is not sufficient for the generation of locomotor behavior by itself without cocaine. Taken together, these findings importantly suggest that GSK3β may need other molecular targets which are co-activated (or deactivated) by psychomotor stimulants like cocaine to contribute to generation of locomotor behaviors. © 2013 International Society for Neurochemistry.

The effects of long-term dopaminergic treatment on locomotor behavior in rats.

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Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco

2014-12-01

Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole-PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions.

The effects of long-term dopaminergic treatment on locomotor behavior in rats

Science.gov (United States)

Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco

2014-01-01

Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole—PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions. PMID:26483930

The effects of long-term dopaminergic treatment on locomotor behavior in rats

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Welinton Alessandro Oliveira de Almeida

2014-12-01

Full Text Available Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL and drug (Pramipexole—PPX groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions.

Cocaine locomotor activation, sensitization and place preference in six inbred strains of mice

Science.gov (United States)

2011-01-01

Background The expanding set of genomics tools available for inbred mouse strains has renewed interest in phenotyping larger sets of strains. The present study aims to explore phenotypic variability among six commonly-used inbred mouse strains to both the rewarding and locomotor stimulating effects of cocaine in a place conditioning task, including several strains or substrains that have not yet been characterized for some or all of these behaviors. Methods C57BL/6J (B6), BALB/cJ (BALB), C3H/HeJ (C3H), DBA/2J (D2), FVB/NJ (FVB) and 129S1/SvImJ (129) mice were tested for conditioned place preference to 20 mg/kg cocaine. Results Place preference was observed in most strains with the exception of D2 and 129. All strains showed a marked increase in locomotor activity in response to cocaine. In BALB mice, however, locomotor activation was context-dependent. Locomotor sensitization to repeated exposure to cocaine was most significant in 129 and D2 mice but was absent in FVB mice. Conclusions Genetic correlations suggest that no significant correlation between conditioned place preference, acute locomotor activation, and locomotor sensitization exists among these strains indicating that separate mechanisms underlie the psychomotor and rewarding effects of cocaine. PMID:21806802

Woodlouse locomotor behavior in the assessment of clean and contaminated field sites

Energy Technology Data Exchange (ETDEWEB)

Bayley, M.; Baatrup, E. [Aarhus Univ. (Denmark). Inst. of Biological Sciences; Bjerregaard, P. [Odense Univ. (Denmark). Inst. of Biology

1997-11-01

Specimens of the woodlouse Oniscus asellus were collected at four clean field sites and from a recently closed iron foundry heavily contaminated with zinc, lead, chromium, and nickel. Each of the 30 woodlice per group was housed individually and acclimatized to laboratory conditions for 2 d on a humid plaster of paris substrate. Thereafter, the locomotor behavior of each animal was measured for 4 h employing automated computer-aided video tracking. Linear discriminant analysis of five locomotor parameters revealed average velocity and path length as the principle components separating the polluted site and control animals. Post hoc analysis of the discriminant variable for animals from all five sites showed that the animals from the polluted site where significantly hyperactive when compared to all controls. Further, control animals collected from sites separated by several hundred kilometers were remarkably similar in their locomotor behavior. This preliminary study highlights the potential utility of quantitative analysis of animal locomotor behavior in environmental monitoring.

Temperature and Population Density Effects on Locomotor Activity of Musca domestica (Diptera: Muscidae)

DEFF Research Database (Denmark)

Schou, T. M.; Faurby, S.; Kjærsgaard, A.

2013-01-01

The behavior of ectotherm organisms is affected by both abiotic and biotic factors. However, a limited number of studies have investigated the synergistic effects on behavioral traits. This study examined the effect of temperature and density on locomotor activity of Musca domestica (L.). Locomot...

Dose and time relationships of the radioprotector WR-2721 on locomotor activity in mice

International Nuclear Information System (INIS)

Landauer, M.R.; Davis, H.D.; Dominitz, J.A.; Weiss, J.F.

1987-01-01

The effects of the radioprotector S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) on locomotor activity were evaluated in CD2F1 male mice. Separate groups of animals (N = 10/group) received an IP injection of vehicle, 25, 50, 100, 200, or 400 mg/kg of WR-2721 immediately before testing. Horizontal and vertical activity were measured using a Digiscan automated animal activity monitor. The latency to onset and duration of action of each dose of the radioprotector were recorded. For both behavioral measures, a significant reduction was observed in activity at doses of 200 and 400 mg/kg. A dose of 200 mg/kg had a 12- to 14-min latency to onset and significantly reduced behavioral activity for 3 hr. Mice injected with 400 mg/kg exhibited locomotor deficits within 8-10 min and were affected for up to 9 hr. The ED50 for horizontal and vertical activities at 1 hr postinjection were determined to be 271 and 105 mg/kg, respectively. The results demonstrate that significant reductions in locomotor activity are exhibited at doses of 200 mg/kg or more and that vertical activity was more sensitive to the disruptive effects of WR-2721 than was horizontal activity

The possible interaction of dopamine system in nucleus accumbens shell and glutamate system of prelimbic region on locomotor activity in rat

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Hatam Ahmadi

2013-06-01

Full Text Available Background: Nucleus accumbens (NAc and prefrontal cortex (PFC dopaminergic and glutamatergic systems are involved in regulating of locomotor activity behaviors. This study has investigated the interaction of NAc shell dopaminergic system and prelimbic glutamatergic systems in regulating locomotor activity and related parameters. Methods: The aim of this study was the effect the drugs injection interaction in the brain of male Wistar rats on locomotor activity and related parameters, in the order of this purpose, open field apparatus that automatically recorded locomotor activity was employed. Unilateral intra-cerebral injection of drugs was done. Results: Unilateral intra-prelimbic injection of D-AP7 (N-methyl-D-aspartic acid= NMDA receptor antagonist; 0.25, 0.5 and 1μg/μl did not alter locomotor activity behaviors. However, infusion of NMDA (0.9μg/μl in this region increased locomotor activity (P<0.01, whereas decreased rearing (P<0.01 and grooming (P<0.01 which was blocked by D-AP7 (0.25μg/μl (P<0.01. Moreover, unilateral infusion of SCH23390 (dopamine D1 receptor antagonist; 0.25, 0.5 and 1μg/μl into the left NAc shell did not alter locomotor activity. However, injection of SKF38393 (dopamine D1 receptor agonist; 4μg/μl into the left NAc shell increased locomotor activity (P<0.05 which was blocked by SCH23390 (0.25μg/μl (P<0.01. Furthermore, the subthreshold dose infusion of SCH23390 (0.25μg/μl into the left NAc shell reduced the effect of intra- prelimbic NMDA on locomotor activity (P<0.01. In addition, intra-NAc shell administration of the subthreshold dose of SKF38393 (1μg/μl potentiated the middle dose (P<0.05, whereas decreased the higher dose of intra-left prelimbic NMDA response (P<0.05 on locomotor activity. Conclusion: The results suggested a modulatory effect of the NAc shell dopaminergic system on increased locomotor activity by activating glutamate system in prelimbic.

Anxiolytic-Like Effects and Increase in Locomotor Activity Induced by Infusions of NMDA into the Ventral Hippocampus in Rat: Interaction with GABAergic System.

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Bina, Payvand; Rezvanfard, Mehrnaz; Ahmadi, Shamseddin; Zarrindast, Mohammad Reza

2014-10-01

In this study, we investigated the role of N-Methyl-D-Aspartate (NMDA) receptors in the ventral hippocampus (VH) and their possible interactions with GABAA system on anxiety-like behaviors. We used an elevated-plus maze test (EPM) to assess anxiety-like behaviors and locomotor activity in male Wistar rats. The results showed that intra-VH infusions of different doses of NMDA (0.25 and 0.5 μg/rat) increased locomotor activity, and also induced anxiolytic-like behaviors, as revealed by a tendency to increase percentage of open arm time (%OAT), and a significant increase in percentage of open arm entries (%OAE). The results also showed that intra-VH infusions of muscimol (0.5 and 1 μg/rat) or bicuculline (0.5 and 1 μg/rat) did not significantly affect anxiety-like behaviors, but bicuculline at dose of 1 μg/rat increased locomotor activity. Intra-VH co-infusions of muscimol (0.5 μg/rat) along with low doses of NMDA (0.0625 and 0.125 μg/rat) showed a tendency to increase %OAT, %OAE and locomotor activity; however, no interaction was observed between the drugs. Interestingly, intra-VH co-infusions of bicuculline (0.5 μg/rat) along with effective doses of NMDA (0.25 and 0.5 μg/rat) decreased %OAT, %OAE and locomotor activity, and a significant interaction between two drugs was observed. It can be concluded that GABAergic system may mediate the anxiolytic-like effects and increase in locomotor activity induced by NMDA in the VH.

Effects of lipopolysaccharide and interleukin-6 on cataleptic immobility and locomotor activity in mice.

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Bazovkina, Daria V; Tibeikina, Marina A; Kulikov, Alexander V; Popova, Nina K

2011-01-10

Catalepsy (animal hypnosis, tonic immobility) is a type of passive defensive behavior. Its exaggerated form is a syndrome of some psychopathological disorders. Numerous neurotransmitters have impact on the regulation of catalepsy. In this paper we demonstrated the involvement of interleukin-6 (IL-6) in the mechanism of cataleptic immobility. Effects of exogenous IL-6 treatment (7.5 and 10μg/kg, i.p) or stimulation of endogenous IL-6 secretion with lipopolysaccharide (LPS) administration (50, 100 and 200μg/kg, i.p.) on catalepsy and locomotor activity were studied in adult C57BL/6 male mice. IL-6 induced catalepsy in 70% (7.5μg/kg) or 72.7% (10μg/kg) of animals with no effect on locomotor activity. LPS administration reduced distance travelled and number of rears in the open field at any dose used, however, only high doses (100 or 200μg/kg) of the toxin induced catalepsy in 50% of mice. This result indicates that IL-6 is involved in the regulation of catalepsy, this effect is specific and does not arise from inhibition of locomotor activity. The study provides a new evidence on participation of IL-6 in mechanisms of abnormal behavior. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Effect of Environmental Conditions and Toxic Compounds on the Locomotor Activity of Pediculus humanus capitis (Phthiraptera: Pediculidae).

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Ortega-Insaurralde, I; Toloza, A C; Gonzalez-Audino, P; Mougabure-Cueto, G A; Alvarez-Costa, A; Roca-Acevedo, G; Picollo, M I

2015-09-01

In this work, we evaluated the effect of environmental variables such as temperature, humidity, and light on the locomotor activity of Pediculus humanus capitis. In addition, we used selected conditions of temperature, humidity, and light to study the effects of cypermethrin and N,N-diethyl-3-methylbenzamide (DEET) on the locomotor activity of head lice. Head lice increased their locomotor activity in an arena at 30°C compared with activity at 20°C. When we tested the influence of the humidity level, the locomotor activity of head lice showed no significant differences related to humidity level, both at 30°C and 20°C. Concerning light influence, we observed that the higher the intensity of light, the slower the movement of head lice. We also demonstrated that sublethal doses of toxics may alter locomotor activity in adults of head lice. Sublethal doses of cypermethrin induced hyperactivated responses in adult head lice. Sublethal doses of DEET evocated hypoactivated responses in head lice. The observation of stereotyped behavior in head lice elicited by toxic compounds proved that measuring locomotor activity in an experimental set-up where environmental conditions are controlled would be appropriate to evaluate compounds of biological importance, such as molecules involved in the host-parasite interaction and intraspecific relationships. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Application of locomotor activity test to evaluate functional injury after global cerebral ischemia in C57BL/6 mice].

Science.gov (United States)

Zhang, Li-quan; Xu, Jia-ni; Wang, Zhen-zhen; Zeng, Li-jun; Ye, Yi-lu; Zhang, Wei-ping; Wei, Er-qing; Zhang, Qi

2014-05-01

To evaluate the application of locomotor activity test in functional injury after global cerebral ischemia (GCI) in C57BL/6 mice. GCI was induced by bilateral carotid arteries occlusion for 30 min in C57BL/6 mice. Mice were divided into sham group, GCI group and minocycline group. Saline or minocycline (45 mg/kg) was i.p. injected once daily for 6 d after ischemia. At Day 6 after ischemia, locomotor activity was recorded for 1 h in open field test. Total distance, central distance, central distance ratio, periphery distance, periphery distance ratio, central time and periphery time were used to evaluate the behavior characteristics of locomotor activity in C57BL/6 mice after ischemia. The survival neuron density was detected by Nissl staining in hippocampus, cortex and striatum. Compared with sham group, total distance, central distance and central time increased and periphery time decreased in C57BL/6 mice after GCI (PsLocomotor activity in open field test can objectively evaluate the behavior injury after GCI in mice. Central distance and central time can be used as indexes of quantitative assessment.

Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors

OpenAIRE

DiGiovanna, J.; Dominici, N.; Friedli, L.; Rigosa, J.; Duis, S.; Kreider, J.; Beauparlant, J.; van den Brand, R.; Schieppati, M.; Micera, S.; Courtine, G.

2016-01-01

Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral context. To investigate this possibility, we recorded whole-body kinematics, muscle synergies, and hindlimb motor cortex modulation in freely moving rats performing a range of natural locomotor pr...

Sex differences in the acute locomotor response to methamphetamine in BALB/c mice.

Science.gov (United States)

Ohia-Nwoko, Odochi; Haile, Colin N; Kosten, Therese A

2017-06-01

Women use methamphetamine more frequently than men and are more vulnerable to its negative psychological effects. Rodent models have been an essential tool for evaluating the sex-dependent effects of psychostimulants; however, evidence of sex differences in the behavioral responses to methamphetamine in mice is lacking. In the present study, we investigated acute methamphetamine-induced (1mg/kg and 4mg/kg) locomotor activation in female and male BALB/c mice. We also evaluated whether basal locomotor activity was associated with the methamphetamine-induced locomotor response. The results indicated that female BALB/c mice displayed enhanced methamphetamine-induced locomotor activity compared to males, while basal locomotor activity was positively correlated with methamphetamine-induced activity in males, but not females. This study is the first to show sex-dependent locomotor effects of methamphetamine in BALB/c mice. Our observations emphasize the importance of considering sex when assessing behavioral responses to methamphetamine. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

Science.gov (United States)

Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

2013-01-01

Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p reproductive synchrony of mature adults, thus increasing reproductive success in this species.

Sexual behavior induction of c-Fos in the nucleus accumbens and amphetamine-stimulated locomotor activity are sensitized by previous sexual experience in female Syrian hamsters.

Science.gov (United States)

Bradley, K C; Meisel, R L

2001-03-15

Dopamine transmission in the nucleus accumbens can be activated by drugs, stress, or motivated behaviors, and repeated exposure to these stimuli can sensitize this dopamine response. The objectives of this study were to determine whether female sexual behavior activates nucleus accumbens neurons and whether past sexual experience cross-sensitizes neuronal responses in the nucleus accumbens to amphetamine. Using immunocytochemical labeling, c-Fos expression in different subregions (shell vs core at the rostral, middle, and caudal levels) of the nucleus accumbens was examined in female hamsters that had varying amounts of sexual experience. Female hamsters, given either 6 weeks of sexual experience or remaining sexually naive, were tested for sexual behavior by exposure to adult male hamsters. Previous sexual experience increased c-Fos labeling in the rostral and caudal levels but not in the middle levels of the nucleus accumbens. Testing for sexual behavior increased labeling in the core, but not the shell, of the nucleus accumbens. To validate that female sexual behavior can sensitize neurons in the mesolimbic dopamine pathway, the locomotor responses of sexually experienced and sexually naive females to an amphetamine injection were then compared. Amphetamine increased general locomotor activity in all females. However, sexually experienced animals responded sooner to amphetamine than did sexually naive animals. These data indicate that female sexual behavior can activate neurons in the nucleus accumbens and that sexual experience can cross-sensitize neuronal responses to amphetamine. In addition, these results provide additional evidence for functional differences between the shell and core of the nucleus accumbens and across its anteroposterior axis.

High Throughput Measurement of Locomotor Sensitization to Volatilized Cocaine in Drosophila melanogaster.

Science.gov (United States)

Filošević, Ana; Al-Samarai, Sabina; Andretić Waldowski, Rozi

2018-01-01

Drosophila melanogaster can be used to identify genes with novel functional roles in neuronal plasticity induced by repeated consumption of addictive drugs. Behavioral sensitization is a relatively simple behavioral output of plastic changes that occur in the brain after repeated exposures to drugs of abuse. The development of screening procedures for genes that control behavioral sensitization has stalled due to a lack of high-throughput behavioral tests that can be used in genetically tractable organism, such as Drosophila . We have developed a new behavioral test, FlyBong, which combines delivery of volatilized cocaine (vCOC) to individually housed flies with objective quantification of their locomotor activity. There are two main advantages of FlyBong: it is high-throughput and it allows for comparisons of locomotor activity of individual flies before and after single or multiple exposures. At the population level, exposure to vCOC leads to transient and concentration-dependent increase in locomotor activity, representing sensitivity to an acute dose. A second exposure leads to further increase in locomotion, representing locomotor sensitization. We validate FlyBong by showing that locomotor sensitization at either the population or individual level is absent in the mutants for circadian genes period (per) , Clock (Clk) , and cycle (cyc) . The locomotor sensitization that is present in timeless (tim) and pigment dispersing factor (pdf) mutant flies is in large part not cocaine specific, but derived from increased sensitivity to warm air. Circadian genes are not only integral part of the neural mechanism that is required for development of locomotor sensitization, but in addition, they modulate the intensity of locomotor sensitization as a function of the time of day. Motor-activating effects of cocaine are sexually dimorphic and require a functional dopaminergic transporter. FlyBong is a new and improved method for inducing and measuring locomotor sensitization

High Throughput Measurement of Locomotor Sensitization to Volatilized Cocaine in Drosophila melanogaster

Directory of Open Access Journals (Sweden)

Ana Filošević

2018-02-01

Full Text Available Drosophila melanogaster can be used to identify genes with novel functional roles in neuronal plasticity induced by repeated consumption of addictive drugs. Behavioral sensitization is a relatively simple behavioral output of plastic changes that occur in the brain after repeated exposures to drugs of abuse. The development of screening procedures for genes that control behavioral sensitization has stalled due to a lack of high-throughput behavioral tests that can be used in genetically tractable organism, such as Drosophila. We have developed a new behavioral test, FlyBong, which combines delivery of volatilized cocaine (vCOC to individually housed flies with objective quantification of their locomotor activity. There are two main advantages of FlyBong: it is high-throughput and it allows for comparisons of locomotor activity of individual flies before and after single or multiple exposures. At the population level, exposure to vCOC leads to transient and concentration-dependent increase in locomotor activity, representing sensitivity to an acute dose. A second exposure leads to further increase in locomotion, representing locomotor sensitization. We validate FlyBong by showing that locomotor sensitization at either the population or individual level is absent in the mutants for circadian genes period (per, Clock (Clk, and cycle (cyc. The locomotor sensitization that is present in timeless (tim and pigment dispersing factor (pdf mutant flies is in large part not cocaine specific, but derived from increased sensitivity to warm air. Circadian genes are not only integral part of the neural mechanism that is required for development of locomotor sensitization, but in addition, they modulate the intensity of locomotor sensitization as a function of the time of day. Motor-activating effects of cocaine are sexually dimorphic and require a functional dopaminergic transporter. FlyBong is a new and improved method for inducing and measuring locomotor

Locomotor activity and tissue levels following acute administration of lambda- and gamma-cyhalothrin in rats

Science.gov (United States)

Pyrethroids produce neurotoxicity that depends, in part, on the chemical structure. Common behavioral effects include locomotor activity changes and specific toxic syndromes (types I and II). In general these neurobehavioral effects correlate well with peak internal dose metric...

Behavioral and locomotor measurements using an open field activity monitoring system for skeletal muscle diseases.

Science.gov (United States)

Tatem, Kathleen S; Quinn, James L; Phadke, Aditi; Yu, Qing; Gordish-Dressman, Heather; Nagaraju, Kanneboyina

2014-09-29

The open field activity monitoring system comprehensively assesses locomotor and behavioral activity levels of mice. It is a useful tool for assessing locomotive impairment in animal models of neuromuscular disease and efficacy of therapeutic drugs that may improve locomotion and/or muscle function. The open field activity measurement provides a different measure than muscle strength, which is commonly assessed by grip strength measurements. It can also show how drugs may affect other body systems as well when used with additional outcome measures. In addition, measures such as total distance traveled mirror the 6 min walk test, a clinical trial outcome measure. However, open field activity monitoring is also associated with significant challenges: Open field activity measurements vary according to animal strain, age, sex, and circadian rhythm. In addition, room temperature, humidity, lighting, noise, and even odor can affect assessment outcomes. Overall, this manuscript provides a well-tested and standardized open field activity SOP for preclinical trials in animal models of neuromuscular diseases. We provide a discussion of important considerations, typical results, data analysis, and detail the strengths and weaknesses of open field testing. In addition, we provide recommendations for optimal study design when using open field activity in a preclinical trial.

Effects of caffeine on locomotor activity in streptozotocin-induced diabetic rats.

Science.gov (United States)

Bădescu, S V; Tătaru, C P; Kobylinska, L; Georgescu, E L; Zahiu, D M; Zăgrean, A M; Zăgrean, L

2016-01-01

Diabetes mellitus modifies the expression of adenosine receptors in the brain. Caffeine acts as an antagonist of A1 and A2A adenosine receptors and was shown to have a dose-dependent biphasic effect on locomotion in mice. The present study investigated the link between diabetes and locomotor activity in an animal model of streptozotocin-induced diabetes, and the effects of a low-medium dose of caffeine in this relation. The locomotor activity was investigated by using Open Field Test at 6 weeks after diabetes induction and after 2 more weeks of chronic caffeine administration. Diabetes decreased locomotor activity (total distance moved and mobility time). Chronic caffeine exposure impaired the locomotor activity in control rats, but not in diabetic rats. Our data suggested that the medium doses of caffeine might block the A2A receptors, shown to have an increased density in the brain of diabetic rats, and improve or at least maintain the locomotor activity, offering a neuroprotective support in diabetic rats. Abbreviations : STZ = streptozotocin, OFT = Open Field Test.

Differences in Monoamine Oxidase Activity in the Brain of Wistar and August Rats with High and Low Locomotor Activity: A Cytochemical Study.

Science.gov (United States)

Sergutina, A V; Rakhmanova, V I

2016-06-01

Monoamine oxidase activity was quantitatively assessed by cytochemical method in brain structures (layers III and V of the sensorimotor cortex, caudate nucleus, nucleus accumbens, hippocampal CA3 field) of rats of August line and Wistar population with high and low locomotor activity in the open fi eld test. Monoamine oxidase activity (substrate tryptamine) predominated in the nucleus accumbens of Wistar rats with high motor activity in comparison with rats with low locomotor activity. In August rats, enzyme activity (substrates tryptamine and serotonin) predominated in the hippocampus of animals with high motor activity. Comparison of August rats with low locomotor activity and Wistar rats with high motor activity (i.e. animals demonstrating maximum differences in motor function) revealed significantly higher activity of the enzyme (substrates tryptamine and serotonin) in the hippocampus of Wistar rats. The study demonstrates clear-cut morphochemical specificity of monoaminergic metabolism based on the differences in the cytochemical parameter "monoamine oxidase activity", in the studied brain structures, responsible for the formation and realization of goal-directed behavior in Wistar and August rats.

Locomotor activity and tissue levels following acute administration of lambda- and gamma-cyhalothrin in rats

Energy Technology Data Exchange (ETDEWEB)

Moser, Virginia C., E-mail: Moser.ginger@epa.gov [Toxicity Assessment Division, National Health Effects and Environmental Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC (United States); Liu, Zhiwei [FMC Corporation, 701 Princeton South Corporate Center, Ewing, NJ (United States); Schlosser, Christopher [Health Effects Division, Office of Pesticide Programs, Office of Chemical Safety and Pollution Prevention, US Environmental Protection Agency, Washington, DC (United States); Spanogle, Terri L.; Chandrasekaran, Appavu [FMC Corporation, 701 Princeton South Corporate Center, Ewing, NJ (United States); McDaniel, Katherine L. [Toxicity Assessment Division, National Health Effects and Environmental Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC (United States)

2016-12-15

Pyrethroids produce neurotoxicity that depends, in part, on the chemical structure. Common behavioral effects include locomotor activity changes and specific toxic syndromes (types I and II). In general these neurobehavioral effects correlate well with peak internal dose metrics. Products of cyhalothrin, a type II pyrethroid, include mixtures of isomers (e.g., λ-cyhalothrin) as well as enriched active isomers (e.g., γ-cyhalothrin). We measured acute changes in locomotor activity in adult male rats and directly correlated these changes to peak brain and plasma concentrations of λ- and γ-cyhalothrin using a within-subject design. One-hour locomotor activity studies were conducted 1.5 h after oral gavage dosing, and immediately thereafter plasma and brains were collected for analyzing tissue levels using LC/MS/MS methods. Both isomers produced dose-related decreases in activity counts, and the effective dose range for γ-cyhalothrin was lower than for λ-cyhalothrin. Doses calculated to decrease activity by 50% were 2-fold lower for the γ-isomer (1.29 mg/kg) compared to λ-cyhalothrin (2.65 mg/kg). Salivation, typical of type II pyrethroids, was also observed at lower doses of γ-cyhalothrin. Administered dose correlated well with brain and plasma concentrations, which furthermore showed good correlations with activity changes. Brain and plasma levels were tightly correlated across doses. While γ-cyhalothrin was 2-fold more potent based on administered dose, the differences based on internal concentrations were less, with γ-cyhalothrin being 1.3- to 1.6-fold more potent than λ-cyhalothrin. These potency differences are consistent with the purity of the λ-isomer (approximately 43%) compared to the enriched isomer γ-cyhalothrin (approximately 98%). Thus, administered dose as well as differences in cyhalothrin isomers is a good predictor of behavioral effects. - Highlights: • Acute changes in locomotor activity were produced by λ- and γ-cyhalothrin. • �

Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

DEFF Research Database (Denmark)

Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

2011-01-01

these observations with observations made from mice examined by wheel-running activity. The study demonstrates that VPAC2 signaling is necessary for a functional circadian clock driving locomotor activity, core body temperature, and heart rate rhythmicity, since VPAC2-deficient mice lose the rhythms in all three...... to that of wild-type mice. The use of telemetric devices to measure circadian locomotor activity, temperature, and heart rate, together with the classical determination of circadian rhythms of wheel-running activity, raises questions about how representative wheel-running activity may be of other behavioral...

Effects of Lactuca sativa extract on exploratory behavior pattern, locomotor activity and anxiety in mice

Directory of Open Access Journals (Sweden)

S.N. Harsha

2012-05-01

Full Text Available Objective: To evaluate antianxiety property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties belongs to Asteraceae family. Methods: Elevated plus maze (EPM, open field test (OFT, rat exposure test, hyponeophagia and marble burying test were performed in mice models to assess the exploratory behaviour and to assess anxiolytic property of hydro-alcohol extract of Lactuca sativa. Diazepam (1 mg/kg body wt. served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and evaluated exploratory behaviour, locomotor and anxiolytic activities. Results: Time spent and number of entries into the open arm was measured in EPM followed by total locomotor activity in OFT and latency to enter the food zone in hyponeophagia. Conclusions: The study suggested that hydro-alcohol extract of Lactuca sativa leaves possess potent anxiolytic property.

Neuropharmacology of light-induced locomotor activation.

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Amato, Davide; Pum, Martin E; Groos, Dominik; Lauber, Andrea C; Huston, Joseph P; Carey, Robert J; de Souza Silva, Maria A; Müller, Christian P

2015-08-01

Presentation of non-aversive light stimuli for several seconds was found to reliably induce locomotor activation and exploratory-like activity. Light-induced locomotor activity (LIA) can be considered a convenient simple model to study sensory-motor activation. LIA was previously shown to coincide with serotonergic and dopaminergic activation in specific cortical areas in freely moving and anesthetized animals. In the present study we explore the neuropharmacology of LIA using a receptor antagonist/agonist approach in rats. The non-selective 5-HT2-receptor antagonist ritanserin (1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. Selective antagonism of either the 5-HT2A-receptor by MDL 11,939 (0.1-0.4 mg/kg, i.p.), or the 5-HT2C-receptor by SDZ SER 082 (0.125-0.5 mg/kg, i.p.), alone or in combination, had no significant influence on LIA. Also the selective 5-HT1A-receptor antagonist, WAY 100635 (0.4 mg/kg, i.p.) did not affect LIA. Neither did the preferential dopamine D2-receptor antagonist, haloperidol (0.025-0.1 mg/kg, i.p.) nor the D2/D3-receptor agonist, quinpirole (0.025-0.5 mg/kg, i.p.) affect the expression of LIA. However, blocking the glutamatergic NMDA-receptor with phencyclidine (PCP, 1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. This effect was also observed with ketamine (10 mg/kg, i.p.). These findings suggest that serotonin and dopamine receptors abundantly expressed in the cortex do not mediate light-stimulus triggered locomotor activity. PCP and ketamine effects, however, suggest an important role of NMDA receptors in LIA. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

Science.gov (United States)

Muchtaridi; Diantini, Adjeng; Subarnas, Anas

2011-01-01

Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L.) leaves, lemongrass (Cymbopogon citrates L.) herbs, ki lemo (Litsea cubeba L.) bark, and laja gowah (Alpinia malaccencis Roxb.) rhizomes on locomotor activity in mice and identify the active component(s) that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%), 0.1 (55.72%), 0.5 (60.75%), and 0.1 mL/cage (47.09%), respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

Effects of ketamine on the unconditioned and conditioned locomotor activity of preadolescent and adolescent rats: impact of age, sex, and drug dose.

Science.gov (United States)

McDougall, Sanders A; Moran, Andrea E; Baum, Timothy J; Apodaca, Matthew G; Real, Vanessa

2017-09-01

Ketamine is used by preadolescent and adolescent humans for licit and illicit purposes. The goal of the present study was to determine the effects of acute and repeated ketamine treatment on the unconditioned behaviors and conditioned locomotor activity of preadolescent and adolescent rats. To assess unconditioned behaviors, female and male rats were injected with ketamine (5-40 mg/kg), and distance traveled was measured on postnatal day (PD) 21-25 or PD 41-45. To assess conditioned activity, male and female rats were injected with saline or ketamine in either a novel test chamber or the home cage on PD 21-24 or PD 41-44. One day later, rats were injected with saline and conditioned activity was assessed. Ketamine produced a dose-dependent increase in the locomotor activity of preadolescent and adolescent rats. Preadolescent rats did not exhibit sex differences, but ketamine-induced locomotor activity was substantially stronger in adolescent females than males. Repeated ketamine treatment neither caused a day-dependent increase in locomotor activity nor produced conditioned activity in preadolescent or adolescent rats. The activity-enhancing effects of ketamine are consistent with the actions of an indirect dopamine agonist, while the inability of ketamine to induce conditioned activity is unlike what is observed after repeated cocaine or amphetamine treatment. This dichotomy could be due to ketamine's ability to both enhance DA neurotransmission and antagonize N-methyl-D-aspartate (NMDA) receptors. Additional research will be necessary to parse out the relative contributions of DA and NMDA system functioning when assessing the behavioral effects of ketamine during early ontogeny.

Oxytocin decreases cocaine taking, cocaine seeking, and locomotor activity in female rats.

Science.gov (United States)

Leong, Kah-Chung; Zhou, Luyi; Ghee, Shannon M; See, Ronald E; Reichel, Carmela M

2016-02-01

Oxytocin has been shown to decrease cocaine taking and seeking in male rats, suggesting potential treatment efficacy for drug addiction. In the present study, we extended these findings to the assessment of cocaine seeking and taking in female rats. Further, we made direct comparisons of oxytocin's impact on cocaine induced locomotor activity in both males and females. In females, systemic oxytocin (0.3, 1.0, 3.0 mg/kg) attenuated lever pressing for cocaine during self-administration and oxytocin (1.0 mg/kg) attenuated cue-induced cocaine seeking following extinction. Cocaine increased baseline locomotor activity to a greater degree in females relative to males. Oxytocin (0.1, 0.3, 1.0, and 3.0 mg/kg) reduced cocaine-induced locomotor activity in females, but not significantly in males. These data illustrate sex similarities in oxytocin's attenuation of cocaine seeking, but sex differences in cocaine-induced locomotor effects. While reductions in cocaine seeking cannot be attributed to a reduction in locomotor activity in males, attenuation of locomotor function cannot be entirely ruled out as an explanation for a decrease in cocaine seeking in females suggesting that oxytocin's effect on cocaine seeking may be mediated by different mechanisms in male and females. PsycINFO Database Record (c) 2016 APA, all rights reserved.

The correspondence between proximal phalanx morphology and locomotion: implications for inferring the locomotor behavior of fossil catarrhines.

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Rein, Thomas R

2011-11-01

Phalanges are considered to be highly informative in the reconstruction of extinct primate locomotor behavior since these skeletal elements directly interact with the substrate during locomotion. Variation in shaft curvature and relative phalangeal length has been linked to differences in the degree of suspension and overall arboreal locomotor activities. Building on previous work, this study investigated these two skeletal characters in a comparative context to analyze function, while taking evolutionary relationships into account. This study examined the correspondence between proportions of suspension and overall substrate usage observed in 17 extant taxa and included angle of curvature and relative phalangeal length. Predictive models based on these traits are reported. Published proportions of different locomotor behaviors were regressed against each phalangeal measurement and a size proxy. The relationship between each behavior and skeletal trait was investigated using ordinary least-squares, phylogenetic generalized least-squares (pGLS), and two pGLS transformation methods to determine the model of best-fit. Phalangeal curvature and relative length had significant positive relationships with both suspension and overall arboreal locomotion. Cross-validation analyses demonstrated that relative length and curvature provide accurate predictions of relative suspensory behavior and substrate usage in a range of extant species when used together in predictive models. These regression equations provide a refined method to assess the amount of suspensory and overall arboreal locomotion characterizing species in the catarrhine fossil record. Copyright © 2011 Wiley-Liss, Inc.

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.

Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part 2. Variability of measurement parameters under toxicant-induced stress

Energy Technology Data Exchange (ETDEWEB)

Grillitsch, B.; Vogl, C.; Wytek, R.

1999-12-01

Spontaneous locomotor behavior of semiadult zebra fish (Brachydanio rerio) was recorded under sublethal short-term exposure to the anionic technical surfactant, linear alkylbenzene sulfonate (C{sub 10-13}-LAS) and cadmium in single compound tests using an automated video-monitoring and object-tracing system. Vertical position and swimming velocity in the horizontal and vertical directions were used as behavioral measurement parameters. Data were analyzed by different statistical methods. In pairwise comparisons, consistent, statistically significant, and toxicant-induced alterations of locomotor behavior were observed only for test concentrations, which also caused aspectoric symptoms of intoxication. This comparatively low sensitivity of the behavioral indication criteria was related to high variation in the measurement parameters and corresponding high, minimum detectable, statistically significant, and toxicant-induced deviations. In contrast, results obtained by regression analysis showed significant trends in locomotor activity over the range of toxicant concentrations tested. Thus, the findings support the inappropriateness of no observed effect concentrations and the lowest observed effect concentrations as summary measures of toxicity and indicate that the regression analysis approach is superior to the analysis of variance approach.

Agomelatine's effect on circadian locomotor rhythm alteration and depressive-like behavior in 6-OHDA lesioned rats.

Science.gov (United States)

Souza, Leonardo C; Martynhak, Bruno J; Bassani, Taysa B; Turnes, Joelle de M; Machado, Meira M; Moura, Eric; Andreatini, Roberto; Vital, Maria A B F

2018-05-01

Parkinson's disease (PD) patients often suffer from circadian locomotor rhythms impairment and depression, important non-motor symptoms. It is known that toxin-based animal models of PD can reproduce these features. In a 6-hydroxydopamine (6-OHDA) intranigral model, we first investigated the possible disturbances on circadian rhythms of locomotor activity. The rats were divided into 6-OHDA and Sham groups. After a partial dopaminergic lesion, the 6-OHDA group showed slight alterations in different circadian locomotor rhythms parameters. In a second experiment, we hypothesized agomelatine, an melatoninergic antidepressant with potential to resynchronize disturbed rhythms, could prevent neuronal damage and rhythm alterations in the same 6-OHDA model. The animals were divided into four groups: 6-OHDA+vehicle, 6-OHDA+ago, Sham+vehicle and 6-OHDA+ago. However, the treated animals (agomelatine 50 mg/kg for 22 days) showed an impaired rhythm robustness, and agomelatine did not induce significant changes in the other circadian parameters nor neuroprotection. Finally, in a third experiment, we examined the effects of agomelatine in the 6-OHDA model regarding depressive-like behavior, evaluated by sucrose preference test. The animals were also divided into four groups: 6-OHDA+vehicle, 6-OHDA+ago, Sham+vehicle and 6-OHDA+ago. The toxin infused animals showed a decrease in sucrose preference in comparison with the vehicle infused animals, however, agomelatine did not prevent this decrease. Our findings indicate that agomelatine worsened circadian locomotor rhythm and was not able to reverse the depressive-like behavior of rats in the 6-OHDA PD model. Copyright © 2018. Published by Elsevier Inc.

Statistical Analysis of Zebrafish Locomotor Response.

Science.gov (United States)

Liu, Yiwen; Carmer, Robert; Zhang, Gaonan; Venkatraman, Prahatha; Brown, Skye Ashton; Pang, Chi-Pui; Zhang, Mingzhi; Ma, Ping; Leung, Yuk Fai

2015-01-01

Zebrafish larvae display rich locomotor behaviour upon external stimulation. The movement can be simultaneously tracked from many larvae arranged in multi-well plates. The resulting time-series locomotor data have been used to reveal new insights into neurobiology and pharmacology. However, the data are of large scale, and the corresponding locomotor behavior is affected by multiple factors. These issues pose a statistical challenge for comparing larval activities. To address this gap, this study has analyzed a visually-driven locomotor behaviour named the visual motor response (VMR) by the Hotelling's T-squared test. This test is congruent with comparing locomotor profiles from a time period. Different wild-type (WT) strains were compared using the test, which shows that they responded differently to light change at different developmental stages. The performance of this test was evaluated by a power analysis, which shows that the test was sensitive for detecting differences between experimental groups with sample numbers that were commonly used in various studies. In addition, this study investigated the effects of various factors that might affect the VMR by multivariate analysis of variance (MANOVA). The results indicate that the larval activity was generally affected by stage, light stimulus, their interaction, and location in the plate. Nonetheless, different factors affected larval activity differently over time, as indicated by a dynamical analysis of the activity at each second. Intriguingly, this analysis also shows that biological and technical repeats had negligible effect on larval activity. This finding is consistent with that from the Hotelling's T-squared test, and suggests that experimental repeats can be combined to enhance statistical power. Together, these investigations have established a statistical framework for analyzing VMR data, a framework that should be generally applicable to other locomotor data with similar structure.

Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

Directory of Open Access Journals (Sweden)

Anas Subarnas

2011-04-01

Full Text Available Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L. leaves, lemongrass (Cymbopogon citrates L. herbs, ki lemo (Litsea cubeba L. bark, and laja gowah (Alpinia malaccencis Roxb. rhizomes on locomotor activity in mice and identify the active component(s that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%, 0.1 (55.72%, 0.5 (60.75%, and 0.1 mL/cage (47.09%, respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

Pharmacological Modulation of 5-HT2C Receptor Activity Produces Bidirectional Changes in Locomotor Activity, Responding for a Conditioned Reinforcer, and Mesolimbic DA Release in C57BL/6 Mice.

Science.gov (United States)

Browne, Caleb J; Ji, Xiaodong; Higgins, Guy A; Fletcher, Paul J; Harvey-Lewis, Colin

2017-10-01

Converging lines of behavioral, electrophysiological, and biochemical evidence suggest that 5-HT 2C receptor signaling may bidirectionally influence reward-related behavior through an interaction with the mesolimbic dopamine (DA) system. Here we directly test this hypothesis by examining how modulating 5-HT 2C receptor activity affects DA-dependent behaviors and relate these effects to changes in nucleus accumbens (NAc) DA release. In C57BL/6 mice, locomotor activity and responding for a conditioned reinforcer (CRf), a measure of incentive motivation, were examined following treatment with three 5-HT 2C receptor ligands: the agonist CP809101 (0.25-3 mg/kg), the antagonist SB242084 (0.25-1 mg/kg), or the antagonist/inverse agonist SB206553 (1-5 mg/kg). We further tested whether doses of these compounds that changed locomotor activity and responding for a CRf (1 mg/kg CP809101, 0.5 mg/kg SB242084, or 2.5 mg/kg SB206553) also altered NAc DA release using in vivo microdialysis in anesthetized mice. CP809101 reduced locomotor activity, responding for a CRf, and NAc DA release. In contrast, both SB242084 and SB206553 enhanced locomotor activity, responding for a CRf, and NAc DA release, although higher doses of SB206553 produced opposite behavioral effects. Pretreatment with the non-selective DA receptor antagonist α-flupenthixol prevented SB242084 from enhancing responding for a CRf. Thus blocking tonic 5-HT 2C receptor signaling can release serotonergic inhibition of mesolimbic DA activity and enhance reward-related behavior. The observed bidirectional effects of 5-HT 2C receptor ligands may have important implications when considering the 5-HT 2C receptor as a therapeutic target for psychiatric disorders, particularly those presenting with motivational dysfunctions.

Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors

NARCIS (Netherlands)

DiGiovanna, J.; Dominici, N.; Friedli, L.; Rigosa, J.; Duis, S.; Kreider, J.; Beauparlant, J.; van den Brand, R.; Schieppati, M.; Micera, S.; Courtine, G.

2016-01-01

Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral

Effects of cholestasis on learning and locomotor activity in bile duct ligated rats.

Science.gov (United States)

Hosseini, Nasrin; Alaei, Hojjatallah; Nasehi, Mohammad; Radahmadi, Maryam; Mohammad Reza, Zarrindast

2014-01-01

Cognitive functions are impaired in patients with liver disease. Bile duct ligation causes cholestasis that impairs liver function. This study investigated the impact of cholestasis progression on the acquisition and retention times in the passive avoidance test and on the locomotor activity of rats. Cholestasis was induced in male Wistar rats by ligating the main bile duct. Locomotor activity, learning and memory were assessed by the passive avoidance learning test at day 7, day 14, and day 21 post-bile duct ligation. The serum levels of bilirubin, alanine aminotransferase, and alkaline phosphatase were measured. The results showed that acquisition time and locomotor activity were not affected at day 7 and day 14, but they were significantly (P locomotor activity were impaired at 21 days after bile duct ligation following the progression of cholestasis.

The hippocampus and appetitive Pavlovian conditioning: effects of excitotoxic hippocampal lesions on conditioned locomotor activity and autoshaping.

Science.gov (United States)

Ito, Rutsuko; Everitt, Barry J; Robbins, Trevor W

2005-01-01

The hippocampus (HPC) is known to be critically involved in the formation of associations between contextual/spatial stimuli and behaviorally significant events, playing a pivotal role in learning and memory. However, increasing evidence indicates that the HPC is also essential for more basic motivational processes. The amygdala, by contrast, is important for learning about the motivational significance of discrete cues. This study investigated the effects of excitotoxic lesions of the rat HPC and the basolateral amygdala (BLA) on the acquisition of a number of appetitive behaviors known to be dependent on the formation of Pavlovian associations between a reward (food) and discrete stimuli or contexts: (1) conditioned/anticipatory locomotor activity to food delivered in a specific context and (2) autoshaping, where rats learn to show conditioned discriminated approach to a discrete visual CS+. While BLA lesions had minimal effects on conditioned locomotor activity, hippocampal lesions facilitated the development of both conditioned activity to food and autoshaping behavior, suggesting that hippocampal lesions may have increased the incentive motivational properties of food and associated conditioned stimuli, consistent with the hypothesis that the HPC is involved in inhibitory processes in appetitive conditioning. (c) 2005 Wiley-Liss, Inc.

Syngeneic B16F10 Melanoma Causes Cachexia and Impaired Skeletal Muscle Strength and Locomotor Activity in Mice

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Fabrício A. Voltarelli

2017-09-01

Full Text Available Muscle wasting has been emerging as one of the principal components of cancer cachexia, leading to progressive impairment of work capacity. Despite early stages melanomas rarely promotes weight loss, the appearance of metastatic and/or solid tumor melanoma can leads to cachexia development. Here, we investigated the B16F10 tumor-induced cachexia and its contribution to muscle strength and locomotor-like activity impairment. C57BL/6 mice were subcutaneously injected with 5 × 104 B16F10 melanoma cells or PBS as a Sham negative control. Tumor growth was monitored during a period of 28 days. Compared to Sham mice, tumor group depicts a loss of skeletal muscle, as well as significantly reduced muscle grip strength and epididymal fat mass. This data are in agreement with mild to severe catabolic host response promoted by elevated serum tumor necrosis factor-alpha (TNF-α, interleukin-6 (IL-6 and lactate dehydrogenase (LDH activity. Tumor implantation has also compromised general locomotor activity and decreased exploratory behavior. Likewise, muscle loss, and elevated inflammatory interleukin were associated to muscle strength loss and locomotor activity impairment. In conclusion, our data demonstrated that subcutaneous B16F10 melanoma tumor-driven catabolic state in response to a pro-inflammatory environment that is associated with impaired skeletal muscle strength and decreased locomotor activity in tumor-bearing mice.

Fluctuation-Driven Neural Dynamics Reproduce Drosophila Locomotor Patterns.

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Andrea Maesani

2015-11-01

Full Text Available The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circuits that drive animal behavior from moment to moment. To examine how fluctuating activity can contribute to action timing, we paired high-resolution measurements of freely walking Drosophila melanogaster with data-driven neural network modeling and dynamical systems analysis. We generated fluctuation-driven network models whose outputs-locomotor bouts-matched those measured from sensory-deprived Drosophila. From these models, we identified those that could also reproduce a second, unrelated dataset: the complex time-course of odor-evoked walking for genetically diverse Drosophila strains. Dynamical models that best reproduced both Drosophila basal and odor-evoked locomotor patterns exhibited specific characteristics. First, ongoing fluctuations were required. In a stochastic resonance-like manner, these fluctuations allowed neural activity to escape stable equilibria and to exceed a threshold for locomotion. Second, odor-induced shifts of equilibria in these models caused a depression in locomotor frequency following olfactory stimulation. Our models predict that activity fluctuations in action selection circuits cause behavioral output to more closely match sensory drive and may therefore enhance navigation in complex sensory environments. Together these data reveal how simple neural dynamics, when coupled with activity fluctuations, can give rise to complex patterns of animal behavior.

Effect of 1 GeV/n Fe particles on cocaine-stimulated locomotor activity

Science.gov (United States)

Vazquez, M.; Bruneus, M.; Gatley, J.; Russell, S.; Billups, A.

Space travel beyond the Earth's protective magnetic field (for example, to Mars) will involve exposure of astronauts to irradiation by high-energy nuclei such as 56Fe (HZE radiation), which are a component of galactic cosmic rays. These particles have high linear energy transfer (LET) and are expected to irreversibly damage cells they traverse. Our working hypothesis is that long-term behavioral alterations are induced after exposure of the brain to 1 GeV/n iron particles with fluences of 1 to 8 particles/cell targets. Previous studies support this notion but are not definitive, especially with regard to long-term effects. Using the Alternating Gradient Synchrotron (AGS) we expose C57 mice to 1 GeV/n 56Fe radiation (head only) at doses of 0, 15, 30, 60, 120 and 240 cGy. There were originally 19 mice per group. The ability of cocaine to increase locomotor activity in 16 of these animals in response to an intraperitoneal injection of cocaine has been measured so far at 1, 4, 8, 12, 16, 20, 24 and 28 weeks. Cocaine-stimulated locomotor activity was chosen in part because it is a behavioral assay with which we have considerable experience. More importantly, the ability to respond to cocaine is a complex behavior involving many neurotransmitter systems and brain circuits. Therefore, the probability of alteration of this behavior by HZE particles was considered high. However, the central circuit is the nigrostriatal dopamine system, in which dopamine is released in striatum from nerve terminals whose cell bodies are located in the substantia nigra. Cocaine activates behavior by blocking dopamine transporters on striatal nerve terminals and therefore elevating the concentration of dopamine in the synapse. Dopamine activates receptors on striatal GABAergic cells that project via other brain regions to the thalamus. Activation of the motor cortex by glutamatergic projections from the thalamus leads ultimately to increased locomotion. The experimental paradigm involves

Activation of the GABAB receptor prevents nicotine-induced locomotor stimulation in mice

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Carla eLobina

2011-12-01

Full Text Available Recent studies demonstrated that activation of the GABAB receptor, either by means of orthosteric agonists or positive allosteric modulators (PAMs, inhibited different nicotine-related behaviors, including intravenous self-administration and conditioned place preference, in rodents. The present study investigated whether the anti-nicotine effects of the GABAB receptor agonist, baclofen, and GABAB PAMs, CGP7930 and GS39783, extend to nicotine stimulant effects. To this end, CD1 mice were initially treated with baclofen (0, 1.25, and 2.5 mg/kg, i.p., CGP7930 (0, 25, and 50 mg/kg, i.g., or GS39783 (0, 25, and 50 mg/kg, i.g., then treated with nicotine (0 and 0.05 mg/kg, s.c., and finally exposed to an automated apparatus for recording of locomotor activity. Pretreatment with doses of baclofen, CGP7930, or GS39783 that did not alter locomotor activity when given with nicotine vehicle fully prevented hyperlocomotion induced by 0.05 mg/kg nicotine. These data extend to nicotine stimulant effects the capacity of baclofen and GABAB PAMs to block the reinforcing, motivational, and rewarding properties of nicotine. These data strengthen the hypothesis that activation of the GABAB receptor may represent a potentially useful, anti-smoking therapeutic strategy.

Impairment of the organization of locomotor and exploratory behaviors in bile duct-ligated rats

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Leke, Renata; de Oliveira, Diogo L; Mussulini, Ben Hur M.

2012-01-01

Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to several problems, including motor impairment. Animal models of chronic liver disease have extensively investigated the mechanisms of this disease. Impairment of locomotor activity has been described in different...... female Wistar rats underwent common bile duct ligation (BDL rats) or the manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent open-field, plus-maze and foot-fault behavioral tasks. The BDL rats developed chronic liver failure...

Limitations to the Generality of Cocaine Locomotor Sensitization

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Marusich, Julie A.; Branch, Marc N.; Dallery, Jesse

2008-01-01

Repeated exposure to cocaine often leads to tolerance to effects on operant behavior, whereas sensitization often develops to effects on locomotor activity. The purpose of the present set of experiments was to examine if locomotor sensitization to cocaine would develop in the presence or absence of an operant contingency in rats. In Experiment 1, rats lever pressed on an FR schedule of reinforcement, and were administered chronic cocaine. Tolerance to effects of cocaine on lever pressing deve...

Effect of thiamethoxam on cockroach locomotor activity is associated with its metabolite clothianidin.

Science.gov (United States)

Benzidane, Yassine; Touinsi, Sarra; Motte, Emilie; Jadas-Hécart, Alain; Communal, Pierre-Yves; Leduc, Lionel; Thany, Steeve H

2010-12-01

In the present study, the effect of thiamethoxam and clothianidin on the locomotor activity of American cockroach, Periplaneta americana (L.), was evaluated. Because it has been proposed that thiamethoxam is metabolised to clothianidin, high-performance liquid chromatography coupled with mass spectrometry was used to evaluate the amount of clothianidin on thiamethoxam-treated cockroaches. One hour after neonicotinoid treatment, the time spent in the open-field-like apparatus significantly increased, suggesting a decrease in locomotor activity. The percentage of cockroaches displaying locomotor activity was significantly reduced 1 h after haemolymph application of 1 nmol g(-1) neonicotinoid, while no significant effect was found after topical and oral administration. However, at 24 and 48 h, all neonicotinoids were able to reduce locomotor activity, depending on their concentrations and the way they were applied. Interestingly, it was found that thiamethoxam was converted to clothianidin 1 h after application, but the amount of clothianidin did not rise proportionately to thiamethoxam, especially after oral administration. The data suggest that the effect of thiamethoxam on cockroach locomotor activity is due in part to clothianidin action because (1) thiamethoxam levels remained persistent 48 h after application and (2) the amount of clothianidin in cockroach tissues was consistent with the toxicity of thiamethoxam. Copyright © 2010 Society of Chemical Industry.

Virus-mediated shRNA knockdown of prodynorphin in the rat nucleus accumbens attenuates depression-like behavior and cocaine locomotor sensitization.

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Cohen, Ami; Whitfield, Timothy W; Kreifeldt, Max; Koebel, Pascale; Kieffer, Brigitte L; Contet, Candice; George, Olivier; Koob, George F

2014-01-01

Dynorphins, endogenous opioid peptides that arise from the precursor protein prodynorphin (Pdyn), are hypothesized to be involved in the regulation of mood states and the neuroplasticity associated with addiction. The current study tested the hypothesis that dynorphin in the nucleus accumbens (NAcc) mediates such effects. More specifically, we examined whether knockdown of Pdyn within the NAcc in rats would alter the expression of depressive-like and anxiety-like behavior, as well as cocaine locomotor sensitization. Wistar rats were injected with adeno-associated viral (AAV) vectors encoding either a Pdyn-specific short hairpin RNA (AAV-shPdyn) or a scrambled shRNA (AAV-shScr) as control. Four weeks later, rats were tested for anxiety-like behavior in the elevated plus maze test and depressive-like behavior in the forced swim test (FST). Finally, rats received one daily injection of saline or cocaine (20 mg/kg, i.p.), followed by assessment of locomotion for 4 consecutive days. Following 3 days of abstinence, the rats completed 2 additional daily cocaine/saline locomotor trials. Pdyn knockdown in the NAcc led to a significant reduction in depressive-like behavior in the FST, but had no effect on anxiety-like behavior in the elevated plus maze. Pdyn knockdown did not alter baseline locomotor behavior, the locomotor response to acute cocaine, or the initial sensitization of the locomotor response to cocaine over the first 4 cocaine treatment days. However, following 3 days abstinence the locomotor response to the cocaine challenge returned to their original levels in the AAV-shPdyn rats while remaining heightened in the AAV-shScr rats. These results suggest that dynorphin in a very specific area of the nucleus accumbens contributes to depressive-like states and may be involved in neuroadaptations in the NAcc that contribute to the development of cocaine addiction as a persistent and lasting condition.

Virus-mediated shRNA knockdown of prodynorphin in the rat nucleus accumbens attenuates depression-like behavior and cocaine locomotor sensitization.

Directory of Open Access Journals (Sweden)

Ami Cohen

Full Text Available Dynorphins, endogenous opioid peptides that arise from the precursor protein prodynorphin (Pdyn, are hypothesized to be involved in the regulation of mood states and the neuroplasticity associated with addiction. The current study tested the hypothesis that dynorphin in the nucleus accumbens (NAcc mediates such effects. More specifically, we examined whether knockdown of Pdyn within the NAcc in rats would alter the expression of depressive-like and anxiety-like behavior, as well as cocaine locomotor sensitization. Wistar rats were injected with adeno-associated viral (AAV vectors encoding either a Pdyn-specific short hairpin RNA (AAV-shPdyn or a scrambled shRNA (AAV-shScr as control. Four weeks later, rats were tested for anxiety-like behavior in the elevated plus maze test and depressive-like behavior in the forced swim test (FST. Finally, rats received one daily injection of saline or cocaine (20 mg/kg, i.p., followed by assessment of locomotion for 4 consecutive days. Following 3 days of abstinence, the rats completed 2 additional daily cocaine/saline locomotor trials. Pdyn knockdown in the NAcc led to a significant reduction in depressive-like behavior in the FST, but had no effect on anxiety-like behavior in the elevated plus maze. Pdyn knockdown did not alter baseline locomotor behavior, the locomotor response to acute cocaine, or the initial sensitization of the locomotor response to cocaine over the first 4 cocaine treatment days. However, following 3 days abstinence the locomotor response to the cocaine challenge returned to their original levels in the AAV-shPdyn rats while remaining heightened in the AAV-shScr rats. These results suggest that dynorphin in a very specific area of the nucleus accumbens contributes to depressive-like states and may be involved in neuroadaptations in the NAcc that contribute to the development of cocaine addiction as a persistent and lasting condition.

Efficacy of Static Magnetic Field for Locomotor Activity of Experimental Osteopenia

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Norimasa Taniguchi

2007-01-01

Full Text Available In order to examine the effectiveness of applying a static magnetic field (SMF for increasing bone mineral density (BMD, we assessed the degree of osteopenia by dual-energy X-ray absorptiometry (DEXA, the metabolism measuring system, and histological examination of bone tissue in an ovariectomized (OVX rat model. Thirty-six female Wistar rats (8 weeks old, 160–180 g were divided into three groups. The rats in the OVX-M group were exposed to SMF for 12 weeks after ovariectomy. The ovariectomized rats in the OVX-D group were not exposed to SMF as a control. The rats in the normal group received neither ovariectomy nor exposure to SMF. Twelve-week exposure to SMF in the OVX-M group inhibited the reduction in BMD that was observed in the OVX-D group. Moreover, in the OVX rats, before exposure to SMF, there was no clear difference in the level of locomotor activity between the active and resting phases, and the pattern of locomotor activity was irregular. After exposure of OVX rats to SMF, the pattern of locomotor activity became diphasic with clear active and resting phases, as was observed in the normal group. In the OVX-M group, the continuity of the trabecular bone was maintained more favorably and bone mass was higher than the respective parameters in the OVX-D group. These results demonstrate that exposure to SMF increased the level of locomotor activity in OVX rats, thereby increasing BMD.

Effects of caffeine and L-phenylisopropyladenosine on locomotor activity of mice

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Buckholtz, N.S.; Middaugh, L.D.

1987-10-01

C57BL/6J and DBA/2J mice were used to determine if possible differences in the behavioral response to caffeine might be related to differences in A1 adenosine receptors. Caffeine stimulated locomotor activity of both strains, but the dose-response relationship and time course of drug action differed according to strain. Although their response to caffeine differed, the strains did not differ in response to the A1 adenosine agonist L-phenylisopropyladenosine (PIA) nor in the binding of the A1 agonist (/sup 3/H)N6-cyclohexyladenosine (CHA) in various brain regions. Thus, the behavioral differences in response to caffeine could not be accounted for by differences in adenosine binding. Of alternative mechanisms, strain differences in A2 receptors appear to be the most promising.

Effect of injection of antisense oligodeoxynucleotides of GAD isozymes into rat ventromedial hypothalamus on food intake and locomotor activity.

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Bannai, M; Ichikawa, M; Nishihara, M; Takahashi, M

1998-02-16

In the ventromedial hypothalamus (VMH), gamma-aminobutyric acid (GABA) plays a role in regulating feeding and running behaviors. The GABA synthetic enzyme, glutamic acid decarboxylase (GAD), consists of two isozymes, GAD65 and GAD67. In the present study, the phosphorothioated antisense oligodeoxynucleotides (ODNs) of each GAD isozyme were injected bilaterally into the VMH of male rats, and food intake, body weight and locomotor activity were monitored. ODNs were incorporated in the water-absorbent polymer (WAP, 0.2 nmol/microliter) so that ODNs were retained at the injection site. Each antisense ODN of GAD65 or GAD67 tended to reduce food intake on day 1 (day of injection=day 0) though not significantly. An injection combining both antisense ODNs significantly decreased food intake only on day 1, but body weight remained significantly lower than the control for 5 days. This suppression of body weight gain could be attributed to a significant increase in locomotor activity between days 3 and 5. Individual treatment with either ODNs did not change locomotor activity. The increase in daily locomotor activity in the group receiving the combined antisense ODNs occurred mainly during the light phase. Neither vehicle (WAP) nor control ODN affected food intake, body weight and locomotor activity. Histological studies indicated that antisense ODN distributed within 800 micron from the edge of the area where WAP was located 24 h after the injection gradually disappeared within days, but still remained within 300 micron m distance even 7 days after the injection. Antisense ODN was effectively incorporated by all the cell types examined, i.e., neurons, astrocytes and microglias. Further, HPLC analysis revealed that antisense ODNs of GAD isozymes, either alone or combined, decreased the content of GABA by 50% in VMH 24 h after the injection. These results indicate that suppression of GABA synthesis by either of the GAD isozymes is synergistically involved in suppressing food

Neonatal programming with testosterone propionate reduces dopamine transporter expression in nucleus accumbens and methylphenidate-induced locomotor activity in adult female rats.

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Dib, Tatiana; Martínez-Pinto, Jonathan; Reyes-Parada, Miguel; Torres, Gonzalo E; Sotomayor-Zárate, Ramón

2018-07-02

Research in programming is focused on the study of stimuli that alters sensitive periods in development, such as prenatal and neonatal stages, that can produce long-term deleterious effects. These effects can occur in various organs or tissues such as the brain, affecting brain circuits and related behaviors. Our laboratory has demonstrated that neonatal programming with sex hormones affects the mesocorticolimbic circuitry, increasing the synthesis and release of dopamine (DA) in striatum and nucleus accumbens (NAcc). However, the behavioral response to psychostimulant drugs such as methylphenidate and the possible mechanism(s) involved have not been studied in adult rats exposed to sex hormones during the first hours of life. Thus, the aim of this study was to examine the locomotor activity induced by methylphenidate (5mg/kg i.p.) and the expression of the DA transporter (DAT) in NAcc of adult rats exposed to a single dose of testosterone propionate (TP: 1mg/50μLs.c.) or estradiol valerate (EV: 0.1mg/50μLs.c.) at postnatal day 1. Our results demonstrated that adult female rats treated with TP have a lower methylphenidate-induced locomotor activity compared to control and EV-treated adult female rats. This reduction in locomotor activity is related with a lower NAcc DAT expression. However, neither methylphenidate-induced locomotor activity nor NAcc DAT expression was affected in EV or TP-treated adult male rats. Our results suggest that early exposure to sex hormones affects long-term dopaminergic brain areas involved in the response to psychostimulants, which could be a vulnerability factor to favor the escalating doses of drugs of abuse. Copyright © 2017 Elsevier B.V. All rights reserved.

Voluntary exercise contributed to an amelioration of abnormal feeding behavior, locomotor activity and ghrelin production concomitantly with a weight reduction in high fat diet-induced obese rats.

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Mifune, Hiroharu; Tajiri, Yuji; Nishi, Yoshihiro; Hara, Kento; Iwata, Shimpei; Tokubuchi, Ichiro; Mitsuzono, Ryouichi; Yamada, Kentaro; Kojima, Masayasu

2015-09-01

In the present study, effects of voluntary exercise in an obese animal model were investigated in relation to the rhythm of daily activity and ghrelin production. Male Sprague-Dawley rats were fed either a high fat diet (HFD) or a chow diet (CD) from four to 16 weeks old. They were further subdivided into either an exercise group (HFD-Ex, CD-Ex) with a running wheel for three days of every other week or sedentary group (HFD-Se, CD-Se). At 16 weeks old, marked increases in body weight and visceral fat were observed in the HFD-Se group, together with disrupted rhythms of feeding and locomotor activity. The induction of voluntary exercise brought about an effective reduction of weight and fat, and ameliorated abnormal rhythms of activity and feeding in the HFD-Ex rats. Wheel counts as voluntary exercise was greater in HFD-Ex rats than those in CD-Ex rats. The HFD-obese had exhibited a deterioration of ghrelin production, which was restored by the induction of voluntary exercise. These findings demonstrated that abnormal rhythms of feeding and locomotor activity in HFD-obese rats were restored by infrequent voluntary exercise with a concomitant amelioration of the ghrelin production and weight reduction. Because ghrelin is related to food anticipatory activity, it is plausible that ghrelin participates in the circadian rhythm of daily activity including eating behavior. A beneficial effect of voluntary exercise has now been confirmed in terms of the amelioration of the daily rhythms in eating behavior and physical activity in an animal model of obesity. Copyright © 2015 Elsevier Inc. All rights reserved.

Adaptive locomotor behavior in larval zebrafish.

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Portugues, Ruben; Engert, Florian

2011-01-01

In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish.

Fenproporex increases locomotor activity and alters energy metabolism, and mood stabilizers reverse these changes: a proposal for a new animal model of mania.

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Rezin, Gislaine T; Furlanetto, Camila B; Scaini, Giselli; Valvassori, Samira S; Gonçalves, Cinara L; Ferreira, Gabriela K; Jeremias, Isabela C; Resende, Wilson R; Cardoso, Mariane R; Varela, Roger B; Quevedo, João; Streck, Emilio L

2014-04-01

Fenproporex (Fen) is converted in vivo into amphetamine, which is used to induce mania-like behaviors in animals. In the present study, we intend to present a new animal model of mania. In order to prove through face, construct, and predictive validities, we evaluated behavioral parameters (locomotor activity, stereotypy activity, and fecal boli amount) and brain energy metabolism (enzymes citrate synthase; malate dehydrogenase; succinate dehydrogenase; complexes I, II, II-III, and IV of the mitochondrial respiratory chain; and creatine kinase) in rats submitted to acute and chronic administration of fenproporex, treated with lithium (Li) and valproate (VPA). The administration of Fen increased locomotor activity and decreased the activity of Krebs cycle enzymes, mitochondrial respiratory chain complexes, and creatine kinase, in most brain structures evaluated. In addition, treatment with mood stabilizers prevented and reversed this effect. Our results are consistent with the literature that demonstrates behavioral changes and mitochondrial dysfunction caused by psychostimulants. These findings suggest that chronic administration of Fen may be a potential animal model of mania.

Initial locomotor sensitivity to cocaine varies widely among inbred mouse strains.

Science.gov (United States)

Wiltshire, T; Ervin, R B; Duan, H; Bogue, M A; Zamboni, W C; Cook, S; Chung, W; Zou, F; Tarantino, L M

2015-03-01

Initial sensitivity to psychostimulants can predict subsequent use and abuse in humans. Acute locomotor activation in response to psychostimulants is commonly used as an animal model of initial drug sensitivity and has been shown to have a substantial genetic component. Identifying the specific genetic differences that lead to phenotypic differences in initial drug sensitivity can advance our understanding of the processes that lead to addiction. Phenotyping inbred mouse strain panels are frequently used as a first step for studying the genetic architecture of complex traits. We assessed locomotor activation following a single, acute 20 mg/kg dose of cocaine (COC) in males from 45 inbred mouse strains and observed significant phenotypic variation across strains indicating a substantial genetic component. We also measured levels of COC, the active metabolite, norcocaine and the major inactive metabolite, benzoylecgonine, in plasma and brain in the same set of inbred strains. Pharmacokinetic (PK) and behavioral data were significantly correlated, but at a level that indicates that PK alone does not account for the behavioral differences observed across strains. Phenotypic data from this reference population of inbred strains can be utilized in studies aimed at examining the role of psychostimulant-induced locomotor activation on drug reward and reinforcement and to test theories about addiction processes. Moreover, these data serve as a starting point for identifying genes that alter sensitivity to the locomotor stimulatory effects of COC. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Conditioned Place Preference to Acetone Inhalation and the Effects on Locomotor Behavior and 18FDG Uptake

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Pai, J.C.; Dewey, S.L.; Schiffer, W.; Lee, D.

2006-01-01

Acetone is a component in many inhalants that have been widely abused. While other solvents have addictive potential, such as toluene, it is unclear whether acetone alone contains addictive properties. The locomotor, relative glucose metabolism and abusive effects of acetone inhalation were studied in animals using the conditioned place preference (CPP) paradigm and [18F]2-fluorodeoxy-D-glucose (18FDG) imaging. The CPP apparatus contains two distinct conditioning chambers and a middle adaptation chamber, each lined with photocells to monitor locomotor activity. Adolescent Sprague-Dawley rats (n=16; 90-110 g) were paired with acetone in least preferred conditioning chamber, determined on the pretest day. The animals were exposed to a 10,000 ppm dose for an hour, alternating days with air. A CPP test was conducted after the 3rd, 6th and 12th pairing. In these same animals, the relative glucose metabolism effects were determined using positron emission tomography (PET) imaging with 18FDG. Following the 3rd pairing, there was a significant aversion to the acetone paired chamber (190.9 ± 13.7 sec and 241.7 ± 16.9 sec, acetone and air, respectively). After the 6th pairing, there was no significant preference observed with equal time spent in each chamber (222 ± 21 sec and 207 ± 20 sec, acetone and air-paired, respectively). A similar trend was observed after the 12th pairing (213 ± 21 sec and 221 ± 22 sec, acetone and air-paired, respectively). Locomotor analysis indicated a significant decrease (p<0.05) from air pairings to acetone pairings on the first and sixth pairings. The observed locomotor activity was characteristic of central nervous system (CNS) depressants, without showing clear abusive effects in this CPP model. In these studies, acetone vapors were not as reinforcing as other solvents, shown by overall lack of preference for the acetone paired side of the chamber. PET imaging indicated a regionally specific distribution of 18FDG uptake following

Activity of Renshaw cells during locomotor-like rhythmic activity in the isolated spinal cord of neonatal mice

DEFF Research Database (Denmark)

Nishimaru, Hiroshi; Restrepo, Carlos E.; Kiehn, Ole

2006-01-01

% of the recorded RCs fired in-phase with the ipsilateral L2 flexor-related rhythm, whereas the rest fired in the extensor phase. Each population of RCs fired throughout the corresponding locomotor phase. All RCs received both excitatory and inhibitory synaptic inputs during the locomotor-like rhythmic activity...

V3 spinal neurons establish a robust and balanced locomotor rhythm during walking.

Science.gov (United States)

Zhang, Ying; Narayan, Sujatha; Geiman, Eric; Lanuza, Guillermo M; Velasquez, Tomoko; Shanks, Bayle; Akay, Turgay; Dyck, Jason; Pearson, Keir; Gosgnach, Simon; Fan, Chen-Ming; Goulding, Martyn

2008-10-09

A robust and well-organized rhythm is a key feature of many neuronal networks, including those that regulate essential behaviors such as circadian rhythmogenesis, breathing, and locomotion. Here we show that excitatory V3-derived neurons are necessary for a robust and organized locomotor rhythm during walking. When V3-mediated neurotransmission is selectively blocked by the expression of the tetanus toxin light chain subunit (TeNT), the regularity and robustness of the locomotor rhythm is severely perturbed. A similar degeneration in the locomotor rhythm occurs when the excitability of V3-derived neurons is reduced acutely by ligand-induced activation of the allatostatin receptor. The V3-derived neurons additionally function to balance the locomotor output between both halves of the spinal cord, thereby ensuring a symmetrical pattern of locomotor activity during walking. We propose that the V3 neurons establish a regular and balanced motor rhythm by distributing excitatory drive between both halves of the spinal cord.

A stochastic locomotor control model for the nurse shark, Ginglymostoma cirratum.

Science.gov (United States)

Gerald, K B; Matis, J H; Kleerekoper, H

1978-06-12

The locomotor behavior of the nurse shark (Ginglymostoma cirratum) is characterized by 17 variables (frequency and ratios of left, right, and total turns; their radians; straight paths (steps); distance travelled; and velocity) Within each of these variables there is an internal time dependency the structure of which was elaborated together with an improved statistical model predicting their behavior within 90% confidence limits. The model allows for the sensitive detection of subtle locomotor response to sensory stimulation as values of variables may exceed the established confidence limits within minutes after onset of the stimulus. The locomotor activity is well described by an autoregression time series model and can be predicted by only seven variables. Six of these form two independently operating clusters. The first one consists of: the number of right turns, the distance travelled and the mean velocity; the second one of: the mean size of right turns, of left turns, and of all turns. The same clustering is obtained independently by a cluster analysis of cross-sections of the seven time series. It is apparent that, among a total of 17 locomotor variables, seven behave as individually independent agents, presumably controlled by seven separate and independent centers. The output of each center can only be predicted by its own behavior. In spite of the individual of the seven variables, their internal structure is similar in important aspects which may result from control by a common command center. The shark locomotor model differs in important aspects from the previously constructed for the goldfish. The interdependence of the locomotor variables in both species may be related to the control mechanisms postulated by von Holst for the coordination of rhythmic fin movements in fishes. A locomotor control model for the nurse shark is proposed.

Individual differences in object permanence performance at 8 months: locomotor experience and brain electrical activity.

Science.gov (United States)

Bell, M A; Fox, N A

1997-12-01

This work was designed to investigate individual differences in hands-and-knees crawling and frontal brain electrical activity with respect to object permanence performance in 76 eight-month-old infants. Four groups of infants (one prelocomotor and 3 with varying lengths of hands-and-knees crawling experience) were tested on an object permanence scale in a research design similar to that used by Kermoian and Campos (1988). In addition, baseline EEG was recorded and used as an indicator of brain development, as in the Bell and Fox (1992) longitudinal study. Individual differences in frontal and occipital EEG power and in locomotor experience were associated with performance on the object permanence task. Infants successful at A-not-B exhibited greater frontal EEG power and greater occipital EEG power than unsuccessful infants. In contrast to Kermoian and Campos (1988), who noted that long-term crawling experience was associated with higher performance on an object permanence scale, infants in this study with any amount of hands and knees crawling experience performed at a higher level on the object permanence scale than prelocomotor infants. There was no interaction among brain electrical activity, locomotor experience, and object permanence performance. These data highlight the value of electrophysiological research and the need for a brain-behavior model of object permanence performance that incorporates both electrophysiological and behavioral factors.

Progesterone receptor antagonist CDB-4124 increases depression-like behavior in mice without affecting locomotor ability

Science.gov (United States)

Beckley, Ethan H.; Scibelli, Angela C.; Finn, Deborah A.

2010-01-01

Progesterone withdrawal has been proposed as an underlying factor in premenstrual syndrome and postpartum depression. Progesterone withdrawal induces forced swim test (FST) immobility in mice, a depression-like behavior, but the contribution of specific receptors to this effect is unclear. The role of progesterone’s GABAA receptor-modulating metabolite allopregnanolone in depression- and anxiety-related behaviors has been extensively documented, but little attention has been paid to the role of progesterone receptors. We administered the classic progesterone receptor antagonist mifepristone (RU-38486) and the specific progesterone receptor antagonist CDB-4124 to mice that had been primed with progesterone for five days, and found that both compounds induced FST immobility reliably, robustly, and in a dose-dependent fashion. Although CDB-4124 increased FST immobility, it did not suppress initial activity in a locomotor test. These findings suggest that decreased progesterone receptor activity contributes to depression-like behavior in mice, consistent with the hypothesis that progesterone withdrawal may contribute to the symptoms of premenstrual syndrome or postpartum depression. PMID:21163582

Progesterone receptor antagonist CDB-4124 increases depression-like behavior in mice without affecting locomotor ability.

Science.gov (United States)

Beckley, Ethan H; Scibelli, Angela C; Finn, Deborah A

2011-07-01

Progesterone withdrawal has been proposed as an underlying factor in premenstrual syndrome and postpartum depression. Progesterone withdrawal induces forced swim test (FST) immobility in mice, a depression-like behavior, but the contribution of specific receptors to this effect is unclear. The role of progesterone's GABA(A) receptor-modulating metabolite allopregnanolone in depression- and anxiety-related behaviors has been extensively documented, but little attention has been paid to the role of progesterone receptors. We administered the classic progesterone receptor antagonist mifepristone (RU-38486) and the specific progesterone receptor antagonist CDB-4124 to mice that had been primed with progesterone for five days, and found that both compounds induced FST immobility reliably, robustly, and in a dose-dependent fashion. Although CDB-4124 increased FST immobility, it did not suppress initial activity in a locomotor test. These findings suggest that decreased progesterone receptor activity contributes to depression-like behavior in mice, consistent with the hypothesis that progesterone withdrawal may contribute to the symptoms of premenstrual syndrome or postpartum depression. Copyright © 2010 Elsevier Ltd. All rights reserved.

Cardiovascular responses to locomotor activity and feeding in unrestrained three-toed sloths, Bradypus variegatus

Directory of Open Access Journals (Sweden)

D.P.F. Duarte

2004-10-01

Full Text Available Heart rate (HR and systolic (SBP, diastolic (DBP and mean (MBP blood pressure were recorded by biotelemetry in nine conscious unrestrained sloths for 1 min every 15 min over a 24-h period. The animals were allowed to freely move in an acoustically isolated and temperature-controlled (24 ± 1ºC experimental room with light-dark cycle (12/12 h. Behavior was closely monitored through a unidirectional visor and classified as resting (sitting or suspended, feeding (chewing and swallowing embauba leaves, Cecropia adenops, or locomotor activity around the tree trunk or on the room floor. Locomotor activity caused statistically significant increases in SBP (+8%, from 121 ± 22 to 131 ± 18 mmHg, DBP (+7%, from 86 ± 17 to 92 ± 10 mmHg, MBP (+8%, from 97 ± 19 to 105 ± 12 mmHg, and HR (+14%, from 84 ± 15 to 96 ± 15 bpm compared to resting values, indicating a possible major influence of the autonomic nervous system on the modulation of cardiac function during this behavior. During feeding, the increase in blood pressure was even higher (SBP +27%, from 119 ± 21 to 151 ± 21 mmHg; DBP +21%, from 85 ± 16 to 103 ± 15 mmHg; MBP +24%, from 96 ± 17 to 119 ± 17 mmHg, while HR remained at 14% (from 84 ± 15 to 96 ± 10 bpm above resting values. The proportionally greater increase in blood pressure than in HR during feeding suggests an increase in peripheral vascular resistance as part of the overall response to this behavior.

Low dose radiation enhances the Locomotor activity of D. melanogaster

Energy Technology Data Exchange (ETDEWEB)

Seong, Ki Moon; Lee, Buyng Sub; Nam Seon Young; Kim, Ji Young; Yang, Kwang Hee; Choi, Tae In; Kim, Cha Soon [Radiation Effect Research Team, Radiation Health Research Institute, Korea Hydro and Nuclear Power Co., Ltd., Gyeongju (Korea, Republic of)

2013-04-15

Mild stresses at low level including radiation can induce the beneficial effects in many vertebrate and invertebrate species. However, a large amount of studies in radiation biology have focused on the detrimental effects of high dose radiation (HDR) such as the increased incidence of cancers and developmental diseases. Low dose radiation (LDR) induces biologically favorable effects in diverse fields, for example, cancer development, genomic instability, immune response, and longevity. Our previous data indicated that LDR promotes cells proliferation of which degree is not much but significant, and microarray data explained that LDR irradiated fruit flies showing the augmented immunity significantly changed the program for gene expression of many genes in Gene Ontology (GO) categories related to metabolic process. Metabolic process in development one of major contributors in organism growth, interbreeding, motility, and aging. Therefore, it is valuable to examine whether LDR change the physiological parameters related to metabolism, and how LDR regulates the metabolism in D. melanogaster. In this study, to investigate that LDR influences change of the metabolism, a representative parameter, locomotor activity. In addition, the activation of several cellular signal molecules was determined to investigate the specific molecular mechanism of LDR effects on the metabolism. We explored whether ionizing radiation affects the motility activity. We performed the RING assays to evaluate the locomotor activity, a representative parameter presenting motility of fruit flies. HDR dramatically decreased the motor activity of irradiated flies. Surprisingly, the irradiated flies at low dose radiation in both acute and chronic showed the significantly increased locomotor activity, compared to non-irradiated flies. Irradiation would induce change of the several signal pathways for flies to respond to it. The activation of some proteins involved in the cells proliferation and stress

Modular diversification of the locomotor system in damselfishes (Pomacentridae).

Science.gov (United States)

Aguilar-Medrano, Rosalía; Frédérich, Bruno; Barber, Paul H

2016-05-01

As fish move and interact with their aquatic environment by swimming, small morphological variations of the locomotor system can have profound implications on fitness. Damselfishes (Pomacentridae) have inhabited coral reef ecosystems for more than 50 million years. As such, habitat preferences and behavior could significantly constrain the morphology and evolvability of the locomotor system. To test this hypothesis, we used phylogenetic comparative methods on morphometric, ecological and behavioral data. While body elongation represented the primary source of variation in the locomotor system of damselfishes, results also showed a diverse suite of morphological combinations between extreme morphologies. Results show clear associations between behavior, habitat preferences, and morphology, suggesting ecological constraints on shape diversification of the locomotor system. In addition, results indicate that the three modules of the locomotor system are weakly correlated, resulting in versatile and independent characters. These results suggest that Pomacentridae is shape may result from the interaction between (1) integrated parts of morphological variation that maintain overall swimming ability and (2) relatively independent parts of the morphology that facilitate adaptation and diversification. © 2016 Wiley Periodicals, Inc.

Behavioral toxicity of selected radioprotectors

Science.gov (United States)

Landauer, M. R.; Davis, H. D.; Kumar, K. S.; Weiss, J. F.

1992-10-01

Effective radioprotection with minimal behavioral disruption is essential for the selection of protective agents to be used in manned spaceflight. This overview summarizes the studies on the behavioral toxicity of selected radioprotectors classified as phosphorothioates (WR-2721, WR-3689), bioactive lipids (16, 16 dimethylprostaglandin E2(DiPGE2), platelet activating factor (PAF), leukotriene C4), and immunomodulators (glucan, synthetic trehalose dicorynomycolate, and interleukin-1). Behavioral toxicity was examined in laboratory mice using a locomotor activity test. For all compounds tested, there was a dose-dependent decrease in locomotor behavior that paralleled the dose-dependent increase in radioprotection. While combinations of radioprotective compounds (DiPGE2 plus WR-2721) increased radioprotection, they also decreased locomotor activity. The central nervous system stimulant, caffeine, was able to mitigate the locomotor decrement produced by WR-3689 or PAF.

Gender-specific alteration of energy balance and circadian locomotor activity in the Crtc1 knockout mouse model of depression

KAUST Repository

Rossetti, Clara

2017-12-06

Obesity and depression are major public health concerns, and there is increasing evidence that they share etiological mechanisms. CREB-regulated transcription coactivator 1 (CRTC1) participates in neurobiological pathways involved in both mood and energy balance regulation. Crtc1 -/- mice rapidly develop a depressive-like and obese phenotype in early adulthood, and are therefore a relevant animal model to explore possible common mechanisms underlying mood disorders and obesity. Here, the obese phenotype of male and female Crtc1 -/- mice was further characterized by investigating CRTC1\\'s role in the homeostatic and hedonic regulation of food intake, as well as its influence on daily locomotor activity. Crtc1 -/- mice showed a strong gender difference in the homeostatic regulation of energy balance. Mutant males were hyperphagic and rapidly developed obesity on normal chow diet, whereas Crtc1 -/- females exhibited mild late-onset obesity without hyperphagia. Overeating of mutant males was accompanied by alterations in the expression of several orexigenic and anorexigenic hypothalamic genes, thus confirming a key role of CRTC1 in the central regulation of food intake. No alteration in preference and conditioned response for saccharine was observed in Crtc1 -/- mice, suggesting that mutant males\\' hyperphagia was not due to an altered hedonic regulation of food intake. Intriguingly, mutant males exhibited a hyperphagic behavior only during the resting (diurnal) phase of the light cycle. This abnormal feeding behavior was associated with a higher diurnal locomotor activity indicating that the lack of CRTC1 may affect circadian rhythmicity. Collectively, these findings highlight the male-specific involvement of CRTC1 in the central control of energy balance and circadian locomotor activity.

Gender-specific alteration of energy balance and circadian locomotor activity in the Crtc1 knockout mouse model of depression

KAUST Repository

Rossetti, Clara; Sciarra, Daniel; Petit, Jean-Marie; Eap, Chin B.; Halfon, Olivier; Magistretti, Pierre J.; Boutrel, Benjamin; Cardinaux, Jean-René

2017-01-01

Obesity and depression are major public health concerns, and there is increasing evidence that they share etiological mechanisms. CREB-regulated transcription coactivator 1 (CRTC1) participates in neurobiological pathways involved in both mood and energy balance regulation. Crtc1 -/- mice rapidly develop a depressive-like and obese phenotype in early adulthood, and are therefore a relevant animal model to explore possible common mechanisms underlying mood disorders and obesity. Here, the obese phenotype of male and female Crtc1 -/- mice was further characterized by investigating CRTC1's role in the homeostatic and hedonic regulation of food intake, as well as its influence on daily locomotor activity. Crtc1 -/- mice showed a strong gender difference in the homeostatic regulation of energy balance. Mutant males were hyperphagic and rapidly developed obesity on normal chow diet, whereas Crtc1 -/- females exhibited mild late-onset obesity without hyperphagia. Overeating of mutant males was accompanied by alterations in the expression of several orexigenic and anorexigenic hypothalamic genes, thus confirming a key role of CRTC1 in the central regulation of food intake. No alteration in preference and conditioned response for saccharine was observed in Crtc1 -/- mice, suggesting that mutant males' hyperphagia was not due to an altered hedonic regulation of food intake. Intriguingly, mutant males exhibited a hyperphagic behavior only during the resting (diurnal) phase of the light cycle. This abnormal feeding behavior was associated with a higher diurnal locomotor activity indicating that the lack of CRTC1 may affect circadian rhythmicity. Collectively, these findings highlight the male-specific involvement of CRTC1 in the central control of energy balance and circadian locomotor activity.

Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity.

Science.gov (United States)

Hasegawa, Yasushi; Inoue, Tatsuro; Kawaminami, Satoshi; Fujita, Miho

2016-07-01

To evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801). Effect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test. Scallop shell extract significantly reduced scopolamine-induced short-term memory impairment and partially reduced scopolamine-induced spatial memory impairment in the Morris water maze test. Scallop shell extract suppressed scopolamine-induced elevation of acetylcholine esterase activity in the cerebral cortex. Treatment with scallop shell extract reversed the increase in locomotor activity induced by scopolamine. Scallop shell extract also suppressed the increase in locomotor activity induced by MK801. Our results provide initial evidence that scallop shell extract reduces scopolamine-induced memory impairment and suppresses MK-801-induced hyperlocomotion. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

Integration of Descending Command Systems for the Generation of Context-Specific Locomotor Behaviors

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Linda H. Kim

2017-10-01

Full Text Available Over the past decade there has been a renaissance in our understanding of spinal cord circuits; new technologies are beginning to provide key insights into descending circuits which project onto spinal cord central pattern generators. By integrating work from both the locomotor and animal behavioral fields, we can now examine context-specific control of locomotion, with an emphasis on descending modulation arising from various regions of the brainstem. Here we examine approach and avoidance behaviors and the circuits that lead to the production and arrest of locomotion.

Efffects of vigabatrin on spontaneous locomotor activity of rats

NARCIS (Netherlands)

Bouwman, B.M.; Rijn, C.M. van; Willems-van Bree, P.C.M.; Coenen, A.M.L.

2003-01-01

Effects of vigibatrin (saline, 125, 250, or 500 mg/kg i.p.) on spontaneous locomotor activity in Wistar rats were investigated. There was a dose dependent decrease in amount of locomotion for doses up to 250 mg/kg. This decrease was measurable 2-4 hours after injection and still became more

Neuronal control of locomotor handedness in Drosophila.

Science.gov (United States)

Buchanan, Sean M; Kain, Jamey S; de Bivort, Benjamin L

2015-05-26

Genetically identical individuals display variability in their physiology, morphology, and behaviors, even when reared in essentially identical environments, but there is little mechanistic understanding of the basis of such variation. Here, we investigated whether Drosophila melanogaster displays individual-to-individual variation in locomotor behaviors. We developed a new high-throughout platform capable of measuring the exploratory behavior of hundreds of individual flies simultaneously. With this approach, we find that, during exploratory walking, individual flies exhibit significant bias in their left vs. right locomotor choices, with some flies being strongly left biased or right biased. This idiosyncrasy was present in all genotypes examined, including wild-derived populations and inbred isogenic laboratory strains. The biases of individual flies persist for their lifetime and are nonheritable: i.e., mating two left-biased individuals does not yield left-biased progeny. This locomotor handedness is uncorrelated with other asymmetries, such as the handedness of gut twisting, leg-length asymmetry, and wing-folding preference. Using transgenics and mutants, we find that the magnitude of locomotor handedness is under the control of columnar neurons within the central complex, a brain region implicated in motor planning and execution. When these neurons are silenced, exploratory laterality increases, with more extreme leftiness and rightiness. This observation intriguingly implies that the brain may be able to dynamically regulate behavioral individuality.

Dose-response characteristics of methylphenidate on locomotor behavior and on sensory evoked potentials recorded from the VTA, NAc, and PFC in freely behaving rats

Directory of Open Access Journals (Sweden)

Swann Alan C

2006-01-01

Full Text Available Abstract Background Methylphenidate (MPD is a psychostimulant commonly prescribed for attention deficit/hyperactivity disorder. The mode of action of the brain circuitry responsible for initiating the animals' behavior in response to psychostimulants is not well understood. There is some evidence that psychostimulants activate the ventral tegmental area (VTA, nucleus accumbens (NAc, and prefrontal cortex (PFC. Methods The present study was designed to investigate the acute dose-response of MPD (0.6, 2.5, and 10.0 mg/kg on locomotor behavior and sensory evoked potentials recorded from the VTA, NAc, and PFC in freely behaving rats previously implanted with permanent electrodes. For locomotor behavior, adult male Wistar-Kyoto (WKY; n = 39 rats were given saline on experimental day 1 and either saline or an acute injection of MPD (0.6, 2.5, or 10.0 mg/kg, i.p. on experimental day 2. Locomotor activity was recorded for 2-h post injection on both days using an automated, computerized activity monitoring system. Electrophysiological recordings were also performed in the adult male WKY rats (n = 10. Five to seven days after the rats had recovered from the implantation of electrodes, each rat was placed in a sound-insulated, electrophysiological test chamber where its sensory evoked field potentials were recorded before and after saline and 0.6, 2.5, and 10.0 mg/kg MPD injection. Time interval between injections was 90 min. Results Results showed an increase in locomotion with dose-response characteristics, while a dose-response decrease in amplitude of the components of sensory evoked field responses of the VTA, NAc, and PFC neurons. For example, the P3 component of the sensory evoked field response of the VTA decreased by 19.8% ± 7.4% from baseline after treatment of 0.6 mg/kg MPD, 37.8% ± 5.9% after 2.5 mg/kg MPD, and 56.5% ± 3.9% after 10 mg/kg MPD. Greater attenuation from baseline was observed in the NAc and PFC. Differences in the intensity of

Sleep pattern and locomotor activity are impaired by doxorubicin in non-tumor-bearing rats.

Science.gov (United States)

Lira, Fabio Santos; Esteves, Andrea Maculano; Pimentel, Gustavo Duarte; Rosa, José Cesar; Frank, Miriam Kannebley; Mariano, Melise Oliveira; Budni, Josiane; Quevedo, João; Santos, Ronaldo Vagner Dos; de Mello, Marco Túlio

2016-01-01

We sought explore the effects of doxorubicin on sleep patterns and locomotor activity. To investigate these effects, two groups were formed: a control group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control or DOXO groups. The sleep patterns were examined by polysomnographic recording and locomotor activity was evaluated in an open-field test. In the light period, the total sleep time and slow wave sleep were decreased, while the wake after sleep onset and arousal were increased in the DOXO group compared with the control group (plocomotor activity.

Olanzapine affects locomotor activity and meal size in male rats

NARCIS (Netherlands)

van der Zwaal, Esther M.; Luijendijk, Mieneke C. M.; Evers, Simon S.; la Fleur, Susanne E.; Adan, Roger A. H.

2010-01-01

Olanzapine is an antipsychotic drug that frequently induces weight gain accompanied by increased fat deposition as a side effect. To investigate how olanzapine affects different aspects of energy balance, we used male rats to determine effects on meal patterns, food preference, locomotor activity

Cell phone-generated radio frequency electromagnetic field effects on the locomotor behaviors of the fishes Poecilia reticulata and Danio rerio.

Science.gov (United States)

Lee, David; Lee, Joshua; Lee, Imshik

2015-01-01

The locomotor behavior of small fish was characterized under a cell phone-generated radio frequency electromagnetic field (RF EMF). The trajectory of movement of 10 pairs of guppy (Poecilia reticulate) and 15 pairs of Zebrafish (Danio rerio) in a fish tank was recorded and tracked under the presence of a cell phone-generated RF EMF. The measures were based on spatial and temporal distributions. A time-series trajectory was utilized to emphasize the dynamic nature of locomotor behavior. Fish movement was recorded in real-time. Their spatial, velocity, turning angle and sinuosity distribution were analyzed in terms of F(v,x), P[n(x,t)], P(v), F (θ) and F(s), respectively. In addition, potential temperature elevation caused by a cellular phone was also examined. We demonstrated that a cellular phone-induced temperature elevation was not relevant, and that our measurements reflected RF EMF-induced effects on the locomotor behavior of Poecilia reticulata and Danio rerio. Fish locomotion was observed under normal conditions, in the visual presence of a cell phone, after feeding, and under starvation. Fish locomotor behavior was random both in normal conditions and in the presence of an off-signaled cell phone. However, there were significant changes in the locomotion of the fish after feeding under the RF EMF. The locomotion of the fed fish was affected in terms of changes in population and velocity distributions under the presence of the RF EMF emitted by the cell phone. There was, however, no significant difference in angular distribution.

Olanzapine affects locomotor activity and meal size in male rats

NARCIS (Netherlands)

van der Zwaal, Esther M.; Luijendijk, Mieneke C. M.; Evers, Simon S.; la Fleur, Susanne E.; Adan, Roger A. H.

2010-01-01

Olanzapine is an antipsychotic drug that frequently induces weight gain accompanied by increased fat deposition as a side effect To investigate how olanzapine affects different aspects of energy balance we used male rats to determine effects on meal patterns food preference locomotor activity and

Grainyhead-like 3 (Grhl3) deficiency in brain leads to altered locomotor activity and decreased anxiety-like behaviors in aged mice.

Science.gov (United States)

Dworkin, Sebastian; Auden, Alana; Partridge, Darren D; Daglas, Maria; Medcalf, Robert L; Mantamadiotis, Theo; Georgy, Smitha R; Darido, Charbel; Jane, Stephen M; Ting, Stephen B

2017-06-01

The highly conserved Grainyhead-like (Grhl) family of transcription factors, comprising three members in vertebrates (Grhl1-3), play critical regulatory roles during embryonic development, cellular proliferation, and apoptosis. Although loss of Grhl function leads to multiple neural abnormalities in numerous animal models, a comprehensive analysis of Grhl expression and function in the mammalian brain has not been reported. Here they show that only Grhl3 expression is detectable in the embryonic mouse brain; particularly within the habenula, an organ known to modulate repressive behaviors. Using both Grhl3-knockout mice (Grhl3 -/- ), and brain-specific conditional deletion of Grhl3 in adult mice (Nestin-Cre/Grhl3 flox/flox ), they performed histological expression analyses and behavioral tests to assess long-term effects of Grhl3 loss on motor co-ordination, spatial memory, anxiety, and stress. They found that complete deletion of Grhl3 did not lead to noticeable structural or cell-intrinsic defects in the embryonic brain; however, aged Grhl3 conditional knockout (cKO) mice showed enlarged lateral ventricles and displayed marked changes in motor function and behaviors suggestive of decreased fear and anxiety. They conclude that loss of Grhl3 in the brain leads to significant alterations in locomotor activity and decreased self-inhibition, and as such, these mice may serve as a novel model of human conditions of impulsive behavior or hyperactivity. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 775-788, 2017. © 2017 Wiley Periodicals, Inc.

Mephedrone interactions with cocaine: prior exposure to the 'bath salt' constituent enhances cocaine-induced locomotor activation in rats.

Science.gov (United States)

Gregg, Ryan A; Tallarida, Christopher S; Reitz, Allen B; Rawls, Scott M

2013-12-01

Concurrent use of mephedrone (4-methylmethcathinone; MEPH) and established drugs of abuse is now commonplace, but knowledge about interactions between these drugs is sparse. The present study was designed to test the hypothesis that prior MEPH exposure enhances the locomotor-stimulant effects of cocaine and methamphetamine (METH). For cocaine experiments, rats pretreated with saline, cocaine (15 mg/kg), or MEPH (15 mg/kg) for 5 days were injected with cocaine after 10 days of drug absence. For METH experiments, rats pretreated with saline, METH (2 mg/kg), or MEPH (15 mg/kg) were injected with METH after 10 days of drug absence. Cocaine challenge produced greater locomotor activity after pretreatment with cocaine or MEPH than after pretreatment with saline. METH challenge produced greater locomotor activity after METH pretreatment than after saline pretreatment; however, locomotor activity in rats pretreated with MEPH or saline and then challenged with METH was not significantly different. The locomotor response to MEPH (15 mg/kg) was not significantly affected by pretreatment with cocaine (15 mg/kg) or METH (0.5, 2 mg/kg). The present demonstration that cocaine-induced locomotor activation is enhanced by prior MEPH exposure suggests that MEPH cross-sensitizes to cocaine and increases cocaine efficacy. Interestingly, MEPH cross-sensitization was not bidirectional and did not extend to METH, suggesting that the phenomenon is sensitive to specific psychostimulants.

S-phenylpiracetam, a selective DAT inhibitor, reduces body weight gain without influencing locomotor activity.

Science.gov (United States)

Zvejniece, Liga; Svalbe, Baiba; Vavers, Edijs; Makrecka-Kuka, Marina; Makarova, Elina; Liepins, Vilnis; Kalvinsh, Ivars; Liepinsh, Edgars; Dambrova, Maija

2017-09-01

S-phenylpiracetam is an optical isomer of phenotropil, which is a clinically used nootropic drug that improves physical condition and cognition. Recently, it was shown that S-phenylpiracetam is a selective dopamine transporter (DAT) inhibitor that does not influence norepinephrine (NE) or serotonin (5-HT) receptors. The aim of the present study was to study the effects of S-phenylpiracetam treatment on body weight gain, blood glucose and leptin levels, and locomotor activity. Western diet (WD)-fed mice and obese Zucker rats were treated daily with peroral administration of S-phenylpiracetam for 8 and 12weeks, respectively. Weight gain and plasma metabolites reflecting glucose metabolism were measured. Locomotor activity was detected in an open-field test. S-phenylpiracetam treatment significantly decreased body weight gain and fat mass increase in the obese Zucker rats and in the WD-fed mice. In addition, S-phenylpiracetam reduced the plasma glucose and leptin concentration and lowered hyperglycemia in a glucose tolerance test in both the mice and the rats. S-phenylpiracetam did not influence locomotor activity in the obese Zucker rats or in the WD-fed mice. The results demonstrate that S-phenylpiracetam reduces body weight gain and improves adaptation to hyperglycemia without stimulating locomotor activity. Our findings suggest that selective DAT inhibitors, such as S-phenylpiracetam, could be potentially useful for treating obesity in patients with metabolic syndrome with fewer adverse health consequences compared to other anorectic agents. Copyright © 2017. Published by Elsevier Inc.

Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

Energy Technology Data Exchange (ETDEWEB)

Zago, A. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Leão, R.M.; Carneiro-de-Oliveira, P.E. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil); Marin, M.T.; Cruz, F.C. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Planeta, C.S. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil)

2011-11-18

Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

International Nuclear Information System (INIS)

Zago, A.; Leão, R.M.; Carneiro-de-Oliveira, P.E.; Marin, M.T.; Cruz, F.C.; Planeta, C.S.

2011-01-01

Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats

Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

Directory of Open Access Journals (Sweden)

A. Zago

2012-01-01

Full Text Available Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although cross-sensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P 28-37 and adult (P60-67 rats received nicotine (0.4 mg/kg, sc or saline (0.9% NaCl, sc and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

Inbreeding affects locomotor activity in Drosophila melanogaster at different ages

DEFF Research Database (Denmark)

Manenti, Tommaso; Pertoldi, Cino; Nasiri Moghadam, Neda

2015-01-01

The ability to move is essential for many behavioural traits closely related to fitness. Here we studied the effect of inbreeding on locomotor activity (LA) of Drosophila melanogaster at different ages under both dark and light regimes. We expected to find a decreased LA in inbred lines compared...

Locomotor Activity and Body Temperature Patterns over a Temperature Gradient in the Highveld Mole-Rat (Cryptomys hottentotus pretoriae).

Science.gov (United States)

Haupt, Meghan; Bennett, Nigel C; Oosthuizen, Maria K

2017-01-01

African mole-rats are strictly subterranean mammals that live in extensive burrow systems. High humidity levels in the burrows prevent mole-rats from thermoregulating using evaporative cooling. However, the relatively stable environment of the burrows promotes moderate temperatures and small daily temperature fluctuations. Mole-rats therefore display a relatively wide range of thermoregulation abilities. Some species cannot maintain their body temperatures at a constant level, whereas others employ behavioural thermoregulation. Here we test the effect of ambient temperature on locomotor activity and body temperature, and the relationship between the two parameters, in the highveld mole-rat. We exposed mole-rats to a 12L:12D and a DD light cycle at ambient temperatures of 30°C, 25°C and 20°C while locomotor activity and body temperature were measured simultaneously. In addition, we investigated the endogenous rhythms of locomotor activity and body temperature at different ambient temperatures. Mole-rats displayed nocturnal activity at all three ambient temperatures and were most active at 20°C, but least active at 30°C. Body temperature was highest at 30°C and lowest at 20°C, and the daily cycle was highly correlated with locomotor activity. We show that the mole-rats have endogenous rhythms for both locomotor activity and body temperature. However, the endogenous body temperature rhythm appears to be less robust compared to the locomotor activity rhythm. Female mole-rats appear to be more sensitive to temperature changes than males, increased heterothermy is evident at lower ambient temperatures, whilst males show smaller variation in their body temperatures with changing ambient temperatures. Mole-rats may rely more heavily on behavioural thermoregulation as it is more energy efficient in an already challenging environment.

Effects of nutmeg consumption on the open field locomotor activities ...

African Journals Online (AJOL)

... was a steady significant difference (p < 0.05) in the behaviours of line crossing and walling. There was no much significant changes (P<0.05) in the behaviours of hinding, grooming and defeacation between the Treatments and Control groups of animals. Keywords: Nutmeg, Wistar rats, Open field, Locomotor activities ...

The 28-day exposure to fenpropathrin decreases locomotor activity and reduces activity of antioxidant enzymes in mice brains.

Science.gov (United States)

Nieradko-Iwanicka, Barbara; Borzęcki, Andrzej

2016-04-01

Fenpropathrin (Fen) is a pyrethroid (Pyr) insecticide. Pyrs are used in veterinary medicine, in agriculture and for domestic purposes. As their use increases, new questions about their side effects and mode of action in non-target organisms arise. The objective of this work was to characterize dose-response relationship for in vivo motor function and memory in mice exposed to Fen for 28 days and to assess its influence on activity of antioxidant enzymes in mice brains. The experiment was performed using 64 female mice. Fen at the dose of 11.9mg/kg of body mass, 5.95mg/kg or 2.38mg/kg was administered ip to the mice for 28 consecutive days. Motor function and spatial working memory were tested on days 7, 14 and 28. On day 29, the animals were sacrificed and brains were used to determine activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Fen significantly decreased locomotor activity in mice receiving the highest dose at every stage of the experiment. Lower doses reduced locomotion on days 7 and 14. Fen did not produce memory impairment. A decrease in activities of SOD and GPx was recorded in mice brains. The decrease of SOD activity in mice brains results from direct inhibition of the enzyme by Fen and/or increased utilization due to excessive free radical formation in conditions of Fen-induced oxidative stress. The reduction in GPx activity is probably due to limited glutathione availability. The reduced locomotor activity is a behavioral demonstration of Fen-induced damage in the dopaminergic system. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Effects of cocaine on norepinephrine stimulated phosphoinositide hydrolysis and locomotor activity in rat

International Nuclear Information System (INIS)

Mosaddeghi, M.

1989-01-01

The function of α 1 -adrenoceptors was determined by stimulating cortical tissue slices, which were pre-labeled with [ 3 H]inositol, with norepinephrine (NE) in the presence of 8 mM LiCl. Results of in vitro studies showed that cocaine 10 μM potentiated maximal NE-stimulated PI hydrolysis by 30%. In addition, the EC 50 was decreased from 3.93 ± 0.42 to 1.91 ± 0.31 μM NE. Concentrations of 0.1-100 μM and 0.1-10 μM cocaine enhanced PI hydrolysis stimulated by 0.3 and 3 μM NE, respectively. The concentration-effect curves for NE-stimulated PI hydrolysis were shifted to the right 100-fold in the presence of 0.1 μM prazosin. Cocaine (10 μM) did not potentiate NE-stimulated PI hydrolysis in the presence of 0.1 μM prazosin. [ 3 H]Prazosin saturation and NE [ 3 H]prazosin competition binding studies using crude membrane preparations showed that 10 μM cocaine did not alter binding parameters B max , K d , Hill slope, and IC 50 . Together, these results implied that cocaine in vitro potentiated NE-stimulated PI hydrolysis by blocking NE reuptake. For in vivo studies, the locomotor activity was determined after an acute or chronic injections of either cocaine or saline. Cocaine or saline-treated rats were killed after measurement of the locomotor activity, and NE-stimulated PI hydrolysis was measured. Acute administration of cocaine 3.2-42 mg/kg (i.p.) produced an inverted U shaped dose-response curve on locomotor activity. The peak increase in locomotor activity was at 32 mg/kg cocaine. A dose of 42 mg/kg cocaine produced a significant depression of maximal NE-stimulated PI hydrolysis

Effects of opioid drugs on dopamine mediated locomotor activity in rats

Energy Technology Data Exchange (ETDEWEB)

Leathern, L L

1986-01-01

Opioid drugs influence various behavioural parameters including locomotor activity in experimental animals. The interaction between the opioid and dopaminergic systems is one possible explanation for the effect of opioid drugs on locomotor activity. In this study behavioural and biochemical assays were done to investigate the interaction between the opioid and dopaminergic systems. Behavioural studies were done by measurement of locomotor activity (LA) of rats after acute or chronic pretreatment with opioid andor dopaminergic drugs. Biochemical studies were in the form of radioligand binding assays, the effect on the number (Bmax) and affinity (K/sub D/) of receptors was measured after chronic pretreatment with opioid andor dopaminergic drugs. The opioid drugs used are morphine, nalbuphine and naloxone. Dopaminergic drugs used included: agonists-apomorphine and piribedil; antagonists-pimozide, haloperidol, chlorpromazine. In the acute situation increased LA was obtained with morphine and the DA agonists. A correlation between the behavioural and biochemical assays was found. Chronic pretreatment with morphine enhanced apomorphine induced LA, this supersensitivity was also measured as an increased receptor density (Bmax) of D2 receptors in the striatum. Chronic morphine pretreatment caused a decrease in morphine induced LA, while this subsensitivity was not apparent in the ligand binding assays - where no change in receptor number was observed. Chronic naloxone pretreatment enhanced morphine induced LA, as well as increased the Bmax of opioid receptors in the whole brain. It is concluded that an interaction between the opioid and dopaminergic systems does exist, and may account for the mechanism of action of the opioids.

[INFLUENCE OF IONIZING RADIATION ON THE LOCOMOTOR ACTIVITY AND BODY WEIGHT OF RATS].

Science.gov (United States)

Saimova, A; Chaizhunusоva, N; Kairkhanova, Y; Uzbеkоv, D; Hоshi, М

2017-02-01

The aim of our study was to study influence of ionizing radiation on the locomotor activity and body weight of rats, for this animals was irradiated by via inhalation. Beta- emitter 56Mn was obtained by neutron activation of powdered MnО2 by using nuclear reactor IVG.1M (experimental facility «Baikal-1», Kurchatov, Kazakhstan). Exposure of rats to radioactive powder had two way, the first experiment was contained only air filter for animal's breathing and the second with the system of forced ventilation. Also we developed the method for observation of the locomotor activity of rats, based on quantitative data. The experiment was conducted on 8 «Wistar» breed white laboratory rats. Statistical analysis was performed using descriptive statistics and non-parametric test. Based on our data, we can say that our method has the advantage over the others is that there is no need to move about the animal out of the box in the test field. So we reduce animal stress factor, as the transfer of an animal from one to second place creates additional stress for him. The initial activity of the pulverized powder in both experiments were 2,74х108Bq, but in the second experiment when we used the system of forced ventilation, internal radiation doses were 0.041±0.0075 Gy, this didn't have effect on locomotor activity of rats (Z= -0,841, р=0,4). In the first experiment where we used only air filter for animal's breathing internal radiation doses were 0.15±0.025 Gr, that showed a decrease in locomotor activity in rats (Z=-6,653, р=0,001). After exposure to ionizing radiation changes in the mammals' weight were not found. Thus, based on our data we have made conclusion, that even after a single irradiation at low dose 0.15±0.025 Gr changes occur in the nervous system.

Plateau properties in mammalian spinal interneurons during transmitter-induced locomotor activity

DEFF Research Database (Denmark)

Kiehn, O.; Johnson, B. R.; Raastad, M.

1996-01-01

We examined the organization of spinal networks controlling locomotion in the isolated spinal cord of the neonatal rat, and in this study we provide the first demonstration of plateau and bursting mechanisms in mammalian interneurons that show locomotor-related activity. Using tight-seal whole...

[Age-specific dynamics of mental working capacity in different regimens of locomotor activity].

Science.gov (United States)

Miakotnykh, V V; Khodasevich, L S

2012-01-01

The present study included a total of 392 practically healthy men aged between 40 and 79 years differing in the character of routine locomotor activity and the training status (from masters of sport of international grade to the subjects who had never been engaged in sporting activities). They were divided into 4 groups each comprised of subjects ranged by age with a ten-year interval. Their mental working capacity was estimated from the results of the correction test. The study demonstrated that the subjects characterized by a high level of day-to-day locomotor activity have higher indices of attention intensity and information processing speed compared with the age-matched ones leading a relatively sedentary lifestyle. Moreover, they have better chances to retain the mental working capacity up to the age of 70 years.

Limb Bone Structural Proportions and Locomotor Behavior in A.L. 288-1 ("Lucy".

Directory of Open Access Journals (Sweden)

Christopher B Ruff

Full Text Available While there is broad agreement that early hominins practiced some form of terrestrial bipedality, there is also evidence that arboreal behavior remained a part of the locomotor repertoire in some taxa, and that bipedal locomotion may not have been identical to that of modern humans. It has been difficult to evaluate such evidence, however, because of the possibility that early hominins retained primitive traits (such as relatively long upper limbs of little contemporaneous adaptive significance. Here we examine bone structural properties of the femur and humerus in the Australopithecus afarensis A.L. 288-1 ("Lucy", 3.2 Myr that are known to be developmentally plastic, and compare them with other early hominins, modern humans, and modern chimpanzees. Cross-sectional images were obtained from micro-CT scans of the original specimens and used to derive section properties of the diaphyses, as well as superior and inferior cortical thicknesses of the femoral neck. A.L. 288-1 shows femoral/humeral diaphyseal strength proportions that are intermediate between those of modern humans and chimpanzees, indicating more mechanical loading of the forelimb than in modern humans, and by implication, a significant arboreal locomotor component. Several features of the proximal femur in A.L. 288-1 and other australopiths, including relative femoral head size, distribution of cortical bone in the femoral neck, and cross-sectional shape of the proximal shaft, support the inference of a bipedal gait pattern that differed slightly from that of modern humans, involving more lateral deviation of the body center of mass over the support limb, which would have entailed increased cost of terrestrial locomotion. There is also evidence consistent with increased muscular strength among australopiths in both the forelimb and hind limb, possibly reflecting metabolic trade-offs between muscle and brain development during hominin evolution. Together these findings imply

Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity

OpenAIRE

HASEGAWA, Yasushi; INOUE, Tatsuro; KAWAMINAMI, Satoshi; FUJITA, Miho

2016-01-01

ObjectiveTo evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801).MethodsEffect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test.ResultsScallop shell extract significantly reduced scopolami...

Chronic low-level arsenic exposure causes gender-specific alterations in locomotor activity, dopaminergic systems, and thioredoxin expression in mice

International Nuclear Information System (INIS)

Bardullas, U.; Limon-Pacheco, J.H.; Giordano, M.; Carrizales, L.; Mendoza-Trejo, M.S.; Rodriguez, V.M.

2009-01-01

Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has been associated with the development of skin and internal organ cancers and cardiovascular disorders, among other diseases. A few studies report decreases in intelligence quotient (IQ), and sensory and motor alterations after chronic As exposure in humans. On the other hand, studies of rodents exposed to high doses of As have found alterations in locomotor activity, brain neurochemistry, behavioral tasks, and oxidative stress. In the present study both male and female C57Bl/6J mice were exposed to environmentally relevant doses of As such as 0.05, 0.5, 5.0, or 50 mg As/L of drinking water for 4 months, and locomotor activity was assessed every month. Male mice presented hyperactivity in the group exposed to 0.5 mg As/L and hypoactivity in the group exposed to 50 mg As/L after 4 months of As exposure, whereas female mice exposed to 0.05, 0.5, and 5.0 mg As/L exhibited hyperactivity in every monthly test during As exposure. Furthermore, striatal and hypothalamic dopamine content was decreased only in female mice. Also decreases in tyrosine hydroxylase (TH) and cytosolic thioredoxin (Trx-1) mRNA expression in striatum and nucleus accumbens were observed in male and female mice, respectively. These results indicate that chronic As exposure leads to gender-dependent alterations in dopaminergic markers and spontaneous locomotor activity, and down-regulation of the antioxidant capacity of the brain.

Rats classified as low or high cocaine locomotor responders: A unique model involving striatal dopamine transporters that predicts cocaine addiction-like behaviors

Science.gov (United States)

Yamamoto, Dorothy J.; Nelson, Anna M.; Mandt, Bruce H.; Larson, Gaynor A.; Rorabaugh, Jacki M.; Ng, Christopher M.C.; Barcomb, Kelsey M.; Richards, Toni L.; Allen, Richard M.; Zahniser, Nancy R.

2013-01-01

Individual differences are a hallmark of drug addiction. Here, we describe a rat model based on differential initial responsiveness to low dose cocaine. Despite similar brain cocaine levels, individual outbred Sprague-Dawley rats exhibit markedly different magnitudes of acute cocaine-induced locomotor activity and, thereby, can be classified as low or high cocaine responders (LCRs or HCRs). LCRs and HCRs differ in drug-induced, but not novelty-associated, hyperactivity. LCRs have higher basal numbers of striatal dopamine transporters (DATs) than HCRs and exhibit marginal cocaine inhibition of in vivo DAT activity and cocaine-induced increases in extracellular DA. Importantly, lower initial cocaine response predicts greater locomotor sensitization, conditioned place preference and greater motivation to self-administer cocaine following low dose acquisition. Further, outbred Long-Evans rats classified as LCRs, versus HCRs, are more sensitive to cocaine’s discriminative stimulus effects. Overall, results to date with the LCR/HCR model underscore the contribution of striatal DATs to individual differences in initial cocaine responsiveness and the value of assessing the influence of initial drug response on subsequent expression of addiction-like behaviors. PMID:23850581

[CHANGES IN THE NUMBER OF NEURONS IN THE MOTOR CORTEX OF RATS AND THEIR LOCOMOTOR ACTIVITY IN THE AGE ASPECT].

Science.gov (United States)

Piavchenko, G A; Shmarkova, L I; Nozdrin, V I

2015-01-01

Using Laboras hardware-software complex, which is a system of automatic registration of behavioral reactions, the locomotor activity 1-, 8- and 16-month-old male rats (12 animals in each group) was recorded followed by counting the number of neuron cell bodies of in the layer V of the motor cortex in Nissl stained slides. It was found that the number of neurons in the motor cortex varied in different age groups. Maximal number of neurons was observed in 8-month-old animals. Motor activity was found to correlate with the number of neurons.

Prenatal Iron Deficiency in Guinea Pigs Increases Locomotor Activity but Does Not Influence Learning and Memory

OpenAIRE

Fiset, Catherine; Rioux, France M.; Surette, Marc E.; Fiset, Sylvain

2015-01-01

The objective of the current study was to determine whether prenatal iron deficiency induced during gestation in guinea pigs affected locomotor activity and learning and memory processes in the progeny. Dams were fed either iron-deficient anemic or iron-sufficient diets throughout gestation and lactation. After weaning, all pups were fed an iron-sufficient diet. On postnatal day 24 and 40, the pups' locomotor activity was observed within an open-field test, and from postnatal day 25 to 40, th...

The effects of exercise on cocaine self-administration, food-maintained responding, and locomotor activity in female rats: importance of the temporal relationship between physical activity and initial drug exposure.

Science.gov (United States)

Smith, Mark A; Witte, Maryam A

2012-12-01

Previous studies have reported that exercise decreases cocaine self-administration in rats with long-term access (8+ weeks) to activity wheels in the home cage. The purpose of this study was to (a) examine the importance of the temporal relationship between physical activity and initial drug exposure, (b) determine the effects of exercise on responding maintained by a nondrug reinforcer (i.e., food), and (c) investigate the effects of exercise on cocaine-induced increases in locomotor activity. To this end, female rats were obtained at weaning and divided into 4 groups: (a) EXE-SED rats were housed in exercise cages for 6 weeks and then transferred to sedentary cages after the first day of behavioral testing; (b) SED-EXE rats were housed in sedentary cages for 6 weeks and then transferred to exercise cages after the first day of behavioral testing; (c) SED-SED rats remained in sedentary cages for the duration of the study; and (d) EXE-EXE rats remained in exercise cages for the duration of the study. Relative to the sedentary group (SED-SED), exercise reduced cocaine self-administration in both groups with access to activity wheels after initial drug exposure (EXE-EXE, SED-EXE) but did not reduce cocaine self-administration in the group with access to activity wheels only before drug exposure (EXE-SED). Exercise also decreased the effects of cocaine on locomotor activity but did not reduce responding maintained by food. These data suggest that exercise may reduce cocaine use in drug-experienced individuals with no prior history of aerobic activity without decreasing other types of positively reinforced behaviors.

Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

DEFF Research Database (Denmark)

Bayley, M; Baatrup, E; Heimbach, U

1995-01-01

It is generally believed that copper causes changes in carabid communities indirectly by reducing food availability, because these animals are frequently found to have only slightly elevated metal contents even close to pollution sources. Using computer-centered video tracking, the locomotor......, but not to effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

Differential neurotoxic effects of in utero and lactational exposure to hydroxylated polychlorinated biphenyl (OH-PCB 106) on spontaneous locomotor activity and motor coordination in young adult male mice.

Science.gov (United States)

Haijima, Asahi; Lesmana, Ronny; Shimokawa, Noriaki; Amano, Izuki; Takatsuru, Yusuke; Koibuchi, Noriyuki

2017-01-01

We investigated whether in utero or lactational exposure to 4-hydroxy-2',3,3',4',5'-pentachlorobiphenyl (OH-PCB 106) affects spontaneous locomotor activity and motor coordination in young adult male mice. For in utero exposure, pregnant C57BL/6J mice received 0.05 or 0.5 mg/kg body weight of OH-PCB 106 or corn oil vehicle via gavage every second day from gestational day 10 to 18. For lactational exposure, the different groups of dams received 0.05 or 0.5 mg/kg body weight of OH-PCB 106 or corn oil vehicle via gavage every second day from postpartum day 3 to 13. At 6-7 weeks of age, the spontaneous locomotor activities of male offspring were evaluated for a 24-hr continuous session in a home cage and in an open field for 30-min. Motor coordination function on an accelerating rotarod was also measured. Mice exposed prenatally to OH-PCB 106 showed increased spontaneous locomotor activities during the dark phase in the home cage and during the first 10-min in the open field compared with control mice. Mice exposed lactationally to OH-PCB 106, however, did not show a time-dependent decrease in locomotor activity in the open field. Instead, their locomotor activity increased significantly during the second 10-min block. In addition, mice exposed lactationally to OH-PCB 106 displayed impairments in motor coordination in the rotarod test. These results suggest that perinatal exposure to OH-PCB 106 affects motor behaviors in young adult male mice. Depending on the period of exposure, OH-PCB 106 may have different effects on neurobehavioral development.

The effects of opioid drugs on dopamine mediated locomotor activity in rats

International Nuclear Information System (INIS)

Leathern, L.L.

1986-12-01

Opioid drugs influence various behavioural parameters including locomotor activity in experimental animals. The interaction between the opioid and dopaminergic systems is one possible explanation for the effect of opioid drugs on locomotor activity. In this study behavioural and biochemical assays were done to investigate the interaction between the opioid and dopaminergic systems. Behavioural studies were done by measurement of locomotor activity (LA) of rats after acute or chronic pretreatment with opioid and/or dopaminergic drugs. Biochemical studies were in the form of radioligand binding assays, the effect on the number (Bmax) and affinity (K D ) of receptors was measured after chronic pretreatment with opioid and/or dopaminergic drugs. The opioid drugs used are morphine, nalbuphine and naloxone. Dopaminergic drugs used included: agonists-apomorphine and piribedil; antagonists-pimozide, haloperidol, chlorpromazine. In the acute situation increased LA was obtained with morphine and the DA agonists. A correlation between the behavioural and biochemical assays was found. Chronic pretreatment with morphine enhanced apomorphine induced LA, this supersensitivity was also measured as an increased receptor density (Bmax) of D2 receptors in the striatum. Chronic morphine pretreatment caused a decrease in morphine induced LA, while this subsensitivity was not apparent in the ligand binding assays - where no change in receptor number was observed. Chronic naloxone pretreatment enhanced morphine induced LA, as well as increased the Bmax of opioid receptors in the whole brain. It is concluded that an interaction between the opioid and dopaminergic systems does exist, and may account for the mechanism of action of the opioids

Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

DEFF Research Database (Denmark)

Bayley, M; Baatrup, E; Heimbach, U

1995-01-01

behavior of adult Pterostichus cupreus carabid beetles was quantified after being raised on copper-contaminated food and soil during larval development. Copper was found to have an acute toxic effect measured in larval mortality, to cause a slight increase in the developmental period of males......It is generally believed that copper causes changes in carabid communities indirectly by reducing food availability, because these animals are frequently found to have only slightly elevated metal contents even close to pollution sources. Using computer-centered video tracking, the locomotor......, but not to effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

Comparative anatomy of the arm muscles of the Japanese monkey (Macaca fuscata) with some comments on locomotor mechanics and behavior.

Science.gov (United States)

Aversi-Ferreira, Tales Alexandre; Aversi-Ferreira, Roqueline A G M F; Bretas, Rafael Vieira; Nishimaru, Hiroshi; Nishijo, Hisao

2016-08-01

The anatomical literature on the genus Macaca has focused mainly on the rhesus monkey. However, some aspects in the positional behaviors of the Japanese monkey may be different from those in rhesus monkey, suggesting that the anatomical details of these species are divergent. Four thoracic limbs of Macaca fuscata adults were dissected. The arm muscles in Japanese macaques are more similar to rhesus monkeys and Papio; these characteristics are closer to those of bearded capuchins than apes, indicating more proximity of this genus to New World primates. The anatomical features observed favor quadrupedal locomotor behaviors on the ground and in arboreal environments. Japanese monkeys, rhesus monkeys, and bearded capuchins, which share more primitive characteristics in their arm muscles, present features that favor both arboreal and quadrupedal locomotor behaviors, whereas apes, mainly Pan and Gorilla, which spend more time on the ground, present more quadrupedal specializations. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Drugs that Target Dopamine Receptors: Changes in Locomotor Activity in Larval Zebrafish

Science.gov (United States)

As part of an effort at the US Environmental Protection Agency to develop a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae. This includes assessing the acute effects of drugs known...

Caffeine-supplemented diet modulates oxidative stress markers and improves locomotor behavior in the lobster cockroach Nauphoeta cinerea.

Science.gov (United States)

da Silva, Cícera Simoni; de Cássia Gonçalves de Lima, Rita; Elekofehinti, Olusola Olalekan; Ogunbolude, Yetunde; Duarte, Antonia Eliene; Rocha, João Batista Teixeira; Alencar de Menezes, Irwin Rose; Barros, Luiz Marivando; Tsopmo, Appolinaire; Lukong, Kiven Erique; Kamdem, Jean Paul

2018-02-25

The effects of caffeine supplementation is well documented in conventional animal models, however, in the lobster cockroaches Nauphoeta cinerea, they have not been reported. Thus, the aim of this study was to investigate the locomotor behavior and biochemical endpoints in the head of the nymphs of N. cinerea following 60 days exposure to food supplemented with 0, 0.5, 1.0, 2.5, 5.0 and 10.0 mg of caffeine/g of diet. The analysis of the locomotor behavior using the video-tracking software, Any-maze, for 12 min revealed that caffeine supplementation caused significant behavioral improvement. There was increase in distance travelled, velocity, frequency of rotation and turn angle (stereotypical behavior such as circling movements), and this was supported by the representative track plots of the path travelled by cockroaches in the open-field arena. In addition, caffeine supplementation markedly increased total thiol and non-protein thiol glutathione (GSH) levels in the heads of cockroaches, and this was in parallel with significant reduction of lipid peroxidation and free Fe(II) content. Taking together, our results indicate that long-term caffeine supplementation may exert preventive effects against oxidative stress and support the use of N. cinerea as an efficient alternative model to assess the efficacy of food molecules. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of insemination and blood-feeding on locomotor activity of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) females under laboratory conditions.

Science.gov (United States)

Lima-Camara, Tamara Nunes; Lima, José Bento Pereira; Bruno, Rafaela Vieira; Peixoto, Alexandre Afranio

2014-07-02

Dengue is an arbovirus disease transmitted by two Aedes mosquitoes: Ae. aegypti and Ae. albopictus. Virgin females of these two species generally show a bimodal and diurnal pattern of activity, with early morning and late afternoon peaks. Although some studies on the flight activity of virgin, inseminated and blood-fed Ae. aegypti females have been carried out under laboratory conditions, little is known about the effects of such physiological states on the locomotor activity of Ae. albopictus and Ae. aegypti females. The aim of this study was to analyze, under laboratory conditions, the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under LD 12:12, at 25°C. Both Ae. albopictus and Ae. aegypti females were obtained from established laboratory colonies. Control groups were represented by virgin/unfed Ae. albopictus and Ae. aegypti females. Experiments were conducted under laboratory conditions, using an activity monitor that registers individual activity every thirty minutes. Virgin/unfed Ae. albopictus and Ae. aegypti females showed a diurnal and bimodal pattern of locomotor activity, with peaks at early morning and late afternoon. Insemination and blood-feeding significantly decreased the locomotor activity of Ae. aegypti females, but inseminated/blood-fed Ae. aegypti and Ae. albopictus females showed a similar significant decrease on the locomotor activity compared to virgin/unfed females. This study is the first demonstration of the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under artificial conditions. Data suggest that Ae. albopictus and Ae. aegypti females respond in different ways to physiological status changes and such divergence between these two dengue vectors, associated with several ecological differences, could be related to the greater dengue vectorial capacity of Ae. aegypti in Americas in comparison to Ae. albopictus.

Voluntary locomotor activity mitigates oxidative damage associated with isolation stress in the prairie vole (Microtus ochrogaster).

Science.gov (United States)

Fletcher, Kelsey L; Whitley, Brittany N; Treidel, Lisa A; Thompson, David; Williams, Annie; Noguera, Jose C; Stevenson, Jennie R; Haussmann, Mark F

2015-07-01

Organismal performance directly depends on an individual's ability to cope with a wide array of physiological challenges. For social animals, social isolation is a stressor that has been shown to increase oxidative stress. Another physiological challenge, routine locomotor activity, has been found to decrease oxidative stress levels. Because we currently do not have a good understanding of how diverse physiological systems like stress and locomotion interact to affect oxidative balance, we studied this interaction in the prairie vole (Microtus ochrogaster). Voles were either pair housed or isolated and within the isolation group, voles either had access to a moving wheel or a stationary wheel. We found that chronic periodic isolation caused increased levels of oxidative stress. However, within the vole group that was able to run voluntarily, longer durations of locomotor activity were associated with less oxidative stress. Our work suggests that individuals who demonstrate increased locomotor activity may be better able to cope with the social stressor of isolation. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Effects of zacopride and BMY25801 (batanopride) on radiation-induced emesis and locomotor behavior in the ferret

International Nuclear Information System (INIS)

King, G.L.; Landauer, M.R.

1990-01-01

The antiemetic and locomotor effects of two substituted benzamides, zacopride and batanopride (BMY25801), were compared in ferrets after bilateral 60Co irradiation at 2, 4 or 6 Gy. Both zacopride and BMY25801 were effective against emesis and related signs. Zacopride, tested at several doses (0.003, 0.03 and 0.3 mg/kg), appeared to be more potent because it abolished emesis at 100-fold lower doses than did BMY25801 (3 mg/kg). The ED50 value for the antiemetic effect of zacopride was 0.026 mg/kg (confidence levels = 0.0095, 0.072 mg/kg). However, analysis of emetic parameters recorded from vomiting animals (e.g., latency to first emesis) demonstrated that BMY25801 provided greater antiemetic protection in this population than zacopride without any apparent side effects. Locomotor activity was significantly depressed by both radiation (all doses) and zacopride alone (0.03 mg/kg and 0.3 mg/kg). BMY25801 alone did not affect locomotor activity, and protected against the radiation-induced locomotor decrement. Although zacopride potentiated the locomotor decrement to radiation, no clear dose-response relationship was evident. Bilateral abdominal vagotomy significantly increased the latency to the first emetic episode and significantly reduced the number of retches, but did not alter the duration of the prodromal response to 4-Gy irradiation. Unilateral vagotomies had no effect. Zacopride (at 0.03 mg/kg and 0.3 mg/kg) remained an effective antiemetic in animals that received a bilateral vagotomy, abolishing emesis in four of eight and two of eight ferrets, respectively. These data suggest that the antiemetic action of zacopride does not fully depend on intact vagal innervation and also acts via other pathways

Age and egg-sac loss determine maternal behaviour and locomotor activity of wolf spiders (Araneae, Lycosidae).

Science.gov (United States)

Ruhland, Fanny; Chiara, Violette; Trabalon, Marie

2016-11-01

Wolf spiders' (Lycosidae) maternal behaviour includes a specific phase called "egg brooding" which consists of guarding and carrying an egg-sac throughout the incubation period. The transport of an egg-sac can restrict mothers' exploratory and locomotor activity, in particular when foraging. The present study details the ontogeny of maternal behaviour and assesses the influence of age of egg-sac (or embryos' developmental stage) on vagrant wolf spider Pardosa saltans females' exploration and locomotion. We observed these spiders' maternal behaviour in the laboratory and evaluated their locomotor activity using a digital activity recording device. Our subjects were virgin females (without egg-sac) and first time mothers (with her egg-sac) who were divided into three groups. The first group of mothers were tested on the day the egg-sac was built (day 0), and the females of the other two groups were tested 10 or 15days after they had built their egg-sac. We evaluated the effects of the presence and the loss of egg-sac on mothers' activity. Pardosa saltans females' behaviour depended on mothers' physiological state and/or age of egg-sac (developmental stage of embryos). Virgin females' behaviour was not modified by the presence of an egg-sac in their environment. Mothers' reactions to the presence, the loss and the recovery of their egg-sac varied during the maternal cycle. Maternal behaviour changed with age of egg-sac, but the levels of locomotor activity of mothers with egg-sacs was similar to those of virgin females. Loss of egg-sac modified the maternal behaviour and locomotor activity of all mothers; these modifications were greater on "day 15" when embryos had emerged from eggs. All mothers were able to retrieve their egg-sacs and to re-attach them to their spinnerets. Copyright © 2016 Elsevier B.V. All rights reserved.

Circadian Clock Protein Content and Daily Rhythm of Locomotor Activity Are Altered after Chronic Exposure to Lead in Rat

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Sabbar, Mariam; Dkhissi-Benyahya, Ouria; Benazzouz, Abdelhamid; Lakhdar-Ghazal, Nouria

2017-01-01

Lead exposure has been reported to produce many clinical features, including parkinsonism. However, its consequences on the circadian rhythms are still unknown. Here we aimed to examine the circadian rhythms of locomotor activity following lead intoxication and investigate the mechanisms by which lead may induce alterations of circadian rhythms in rats. Male Wistar rats were injected with lead or sodium acetate (10 mg/kg/day, i.p.) during 4 weeks. Both groups were tested in the “open field” to quantify the exploratory activity and in the rotarod to evaluate motor coordination. Then, animals were submitted to continuous 24 h recordings of locomotor activity under 14/10 Light/dark (14/10 LD) cycle and in complete darkness (DD). At the end of experiments, the clock proteins BMAL1, PER1-2, and CRY1-2 were assayed in the suprachiasmatic nucleus (SCN) using immunohistochemistry. We showed that lead significantly reduced the number of crossing in the open field, impaired motor coordination and altered the daily locomotor activity rhythm. When the LD cycle was advanced by 6 h, both groups adjusted their daily locomotor activity to the new LD cycle with high onset variability in lead-intoxicated rats compared to controls. Lead also led to a decrease in the number of immunoreactive cells (ir-) of BMAL1, PER1, and PER2 without affecting the number of ir-CRY1 and ir-CRY2 cells in the SCN. Our data provide strong evidence that lead intoxication disturbs the rhythm of locomotor activity and alters clock proteins expression in the SCN. They contribute to the understanding of the mechanism by which lead induce circadian rhythms disturbances. PMID:28970786

Synchronization to light and mealtime of daily rhythms of locomotor activity, plasma glucose and digestive enzymes in the Nile tilapia (Oreochromis niloticus).

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Guerra-Santos, Bartira; López-Olmeda, José Fernando; de Mattos, Bruno Olivetti; Baião, Alice Borba; Pereira, Denise Soledade Peixoto; Sánchez-Vázquez, Francisco Javier; Cerqueira, Robson Bahia; Albinati, Ricardo Castelo Branco; Fortes-Silva, Rodrigo

2017-02-01

The light-dark cycle and feeding can be the most important factors acting as synchronizers of biological rhythms. In this research we aimed to evaluate synchronization to feeding schedule of daily rhythms of locomotor activity and digestive enzymes of tilapia. For that purpose, 120 tilapias (65.0±0.6g) were distributed in 12 tanks (10 fish per tank) and divided into two groups. One group was fed once a day at 11:00h (zeitgeber time, ZT6) (ML group) and the other group was fed at 23:00h (ZT18) (MD group). The fish were anesthetized to collect samples of blood, stomach and midgut at 4-hour intervals over a period of 24h. Fish fed at ML showed a diurnal locomotor activity (74% of the total daily activity occurring during the light phase) and synchronization to the feeding schedule, as this group showed anticipation to the feeding time. Fish fed at MD showed a disruption in the pattern of locomotor activity and became less diurnal (59%). Alkaline protease activity in the midgut showed daily rhythm with the achrophase at the beginning of the dark phase in both ML and MD groups. Acid protease and amylase did not show significant daily rhythms. Plasma glucose showed a daily rhythm with the achrophase shifted by 12h in the ML and MD groups. These results revealed that the feeding time and light cycle synchronize differently the daily rhythms of behavior, digestive physiology and plasma metabolites in the Nile tilapia, which indicate the plasticity of the circadian system and its synchronizers. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of Error Augmentation on Brain Activation and Motor Learning of a Complex Locomotor Task

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Laura Marchal-Crespo

2017-09-01

Full Text Available Up to date, the functional gains obtained after robot-aided gait rehabilitation training are limited. Error augmenting strategies have a great potential to enhance motor learning of simple motor tasks. However, little is known about the effect of these error modulating strategies on complex tasks, such as relearning to walk after a neurologic accident. Additionally, neuroimaging evaluation of brain regions involved in learning processes could provide valuable information on behavioral outcomes. We investigated the effect of robotic training strategies that augment errors—error amplification and random force disturbance—and training without perturbations on brain activation and motor learning of a complex locomotor task. Thirty-four healthy subjects performed the experiment with a robotic stepper (MARCOS in a 1.5 T MR scanner. The task consisted in tracking a Lissajous figure presented on a display by coordinating the legs in a gait-like movement pattern. Behavioral results showed that training without perturbations enhanced motor learning in initially less skilled subjects, while error amplification benefited better-skilled subjects. Training with error amplification, however, hampered transfer of learning. Randomly disturbing forces induced learning and promoted transfer in all subjects, probably because the unexpected forces increased subjects' attention. Functional MRI revealed main effects of training strategy and skill level during training. A main effect of training strategy was seen in brain regions typically associated with motor control and learning, such as, the basal ganglia, cerebellum, intraparietal sulcus, and angular gyrus. Especially, random disturbance and no perturbation lead to stronger brain activation in similar brain regions than error amplification. Skill-level related effects were observed in the IPS, in parts of the superior parietal lobe (SPL, i.e., precuneus, and temporal cortex. These neuroimaging findings

Modular Diversification of the Locomotor System in Damselfishes (Pomacentridae)

OpenAIRE

Aguilar-Medrano, Rosalia; Frederich, Bruno; Barber, Paul H.

2016-01-01

As fish move and interact with their aquatic environment by swimming, small morphological variations of the locomotor system can have profound implications on fitness. Damselfishes (Pomacentridae) have inhabited coral reef ecosystems for more than 50 million years. As such, habitat preferences and behavior could significantly constrain the morphology and evolvability of the locomotor system. To test this hypothesis, we used phylogenetic comparative methods on morphometric, ecological and beha...

Dissociation of corticotropin-releasing factor receptor subtype involvement in sensitivity to locomotor effects of methamphetamine and cocaine.

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Giardino, William J; Mark, Gregory P; Stenzel-Poore, Mary P; Ryabinin, Andrey E

2012-02-01

Enhanced sensitivity to the euphoric and locomotor-activating effects of psychostimulants may influence an individual's predisposition to drug abuse and addiction. While drug-induced behaviors are mediated by the actions of several neurotransmitter systems, past research revealed that the corticotropin-releasing factor (CRF) system is important in driving the acute locomotor response to psychostimulants. We previously reported that genetic deletion of the CRF type-2 receptor (CRF-R2), but not the CRF type-1 receptor (CRF-R1) dampened the acute locomotor stimulant response to methamphetamine (1 mg/kg). These results contrasted with previous studies implicating CRF-R1 in the locomotor effects of psychostimulants. Since the majority of previous studies focused on cocaine, rather than methamphetamine, we set out to test the hypothesis that these drugs differentially engage CRF-R1 and CRF-R2. We expanded our earlier findings by first replicating our previous experiments at a higher dose of methamphetamine (2 mg/kg), and by assessing the effects of the CRF-R1-selective antagonist CP-376,395 (10 mg/kg) on methamphetamine-induced locomotor activity. Next, we used both genetic and pharmacological tools to examine the specific components of the CRF system underlying the acute locomotor response to cocaine (5-10 mg/kg). While genetic deletion of CRF-R2 dampened the locomotor response to methamphetamine (but not cocaine), genetic deletion and pharmacological blockade of CRF-R1 dampened the locomotor response to cocaine (but not methamphetamine). These findings highlight the differential involvement of CRF receptors in acute sensitivity to two different stimulant drugs of abuse, providing an intriguing basis for the development of more targeted therapeutics for psychostimulant addiction.

The effects of the novel DA D3 receptor antagonist SR 21502 on cocaine reward, cocaine seeking and cocaine-induced locomotor activity in rats.

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Galaj, E; Ananthan, S; Saliba, M; Ranaldi, Robert

2014-02-01

There is a focus on developing D3 receptor antagonists as cocaine addiction treatments. We investigated the effects of a novel selective D3 receptor antagonist, SR 21502, on cocaine reward, cocaine-seeking, food reward, spontaneous locomotor activity and cocaine-induced locomotor activity in rats. In Experiment 1, rats were trained to self-administer cocaine under a progressive ratio (PR) schedule of reinforcement and tested with vehicle or one of three doses of SR 21502. In Experiment 2, animals were trained to self-administer cocaine under a fixed ratio schedule of reinforcement followed by extinction of the response. Then, animals were tested with vehicle or one of the SR 21502 doses on cue-induced reinstatement of responding. In Experiment 3, animals were trained to lever press for food under a PR schedule and tested with vehicle or one dose of the compound. In Experiments 4 and 5, in separate groups of animals, the vehicle and three doses of SR 21502 were tested on spontaneous or cocaine (10 mg/kg, IP)-induced locomotor activity, respectively. SR 21502 produced significant, dose-related (3.75, 7.5 and 15 mg/kg) reductions in breakpoint for cocaine self-administration, cue-induced reinstatement (3.75, 7.5 and 15 mg/kg) and cocaine-induced locomotor activity (3.75, 7.5 and 15 mg/kg) but failed to reduce food self-administration and spontaneous locomotor activity. SR 21502 decreases cocaine reward, cocaine-seeking and locomotor activity at doses that have no effect on food reward or spontaneous locomotor activity. These data suggest SR 21502 may selectively inhibit cocaine's rewarding, incentive motivational and stimulant effects.

Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

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Dimitri Ryczko

2017-05-01

Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

The Rewarding and Locomotor-Sensitizing Effects of Repeated Cocaine Administration are Distinct and Separable in Mice

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Riday, Thorfinn T.; Kosofsky, Barry E.; Malanga, C.J.

2011-01-01

Repeated psychostimulant exposure progressively increases their potency to stimulate motor activity in rodents. This behavioral or locomotor sensitization is considered a model for some aspects of drug addiction in humans, particularly drug craving during abstinence. However, the role of increased motor behavior in drug reward remains incompletely understood. Intracranial self-stimulation (ICSS) was measured concurrently with locomotor activity to determine if acute intermittent cocaine administration had distinguishable effects on motor behavior and perception of brain stimulation-reward (BSR) in the same mice. Sensitization is associated with changes in neuronal activity and glutamatergic neurotransmission in brain reward circuitry. Expression of AMPA receptor subunits (GluR1 and GluR2) and CRE binding protein (CREB) was measured in the ventral tegmental area (VTA), dorsolateral striatum (STR) and nucleus accumbens (NAc) before and after a sensitizing regimen of cocaine, with and without ICSS. Repeated cocaine administration sensitized mice to its locomotor stimulating effects but not its ability to potentiate BSR. ICSS increased GluR1 in the VTA but not NAc or STR, demonstrating selective changes in protein expression with electrical stimulation of discrete brain structures. Repeated cocaine reduced GluR1, GluR2 and CREB expression in the NAc, and reductions of GluR1 and GluR2 but not CREB were further enhanced by ICSS. These data suggest that the effects of repeated cocaine exposure on reward and motor processes are dissociable in mice, and that reduction of excitatory neurotransmission in the NAc may predict altered motor function independently from changes in reward perception. PMID:22197517

Use of the Open Field Maze to measure locomotor and anxiety-like behavior in mice.

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Seibenhener, Michael L; Wooten, Michael C

2015-02-06

Animal models have proven to be invaluable to researchers trying to answer questions regarding the mechanisms of behavior. The Open Field Maze is one of the most commonly used platforms to measure behaviors in animal models. It is a fast and relatively easy test that provides a variety of behavioral information ranging from general ambulatory ability to data regarding the emotionality of the subject animal. As it relates to rodent models, the procedure allows the study of different strains of mice or rats both laboratory bred and wild-captured. The technique also readily lends itself to the investigation of different pharmacological compounds for anxiolytic or anxiogenic effects. Here, a protocol for use of the open field maze to describe mouse behaviors is detailed and a simple analysis of general locomotor ability and anxiety-related emotional behaviors between two strains of C57BL/6 mice is performed. Briefly, using the described protocol we show Wild Type mice exhibited significantly less anxiety related behaviors than did age-matched Knock Out mice while both strains exhibited similar ambulatory ability.

Locomotor sensitization to ethanol: Contribution of b-Endorphin

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Stephani eDempsey

2012-08-01

Full Text Available Alcohol use disorders, like all drug addictions, involve a constellation of adaptive changes throughout the brain. Neural activity underlying changes in the rewarding properties of alcohol reflect changes in dopamine transmission in mesolimbic and nigrostriatal pathways and these effects are modulated by endogenous opioids such as b-Endorphin. In order to study the role of b-Endorphin in the development of locomotor sensitization to repeated EtOH exposure, we tested transgenic mice that vary in their capacity to synthesize this peptide as a result of constitutive modification of the Pomc gene. Our results indicate that mice deficient in b-Endorphin show attenuated locomotor activation following an acute injection of EtOH (2 g/kg and, in contrast to wildtype mice, fail to demonstrate locomotor sensitization after 12 days of repeated EtOH injections. These data support the idea that b-Endorphin modulates the locomotor effects of EtOH and contributes to the neuroadaptive changes associated with chronic use.

Speed-Dependent Modulation of the Locomotor Behavior in Adult Mice Reveals Attractor and Transitional Gaits.

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Lemieux, Maxime; Josset, Nicolas; Roussel, Marie; Couraud, Sébastien; Bretzner, Frédéric

2016-01-01

Locomotion results from an interplay between biomechanical constraints of the muscles attached to the skeleton and the neuronal circuits controlling and coordinating muscle activities. Quadrupeds exhibit a wide range of locomotor gaits. Given our advances in the genetic identification of spinal and supraspinal circuits important to locomotion in the mouse, it is now important to get a better understanding of the full repertoire of gaits in the freely walking mouse. To assess this range, young adult C57BL/6J mice were trained to walk and run on a treadmill at different locomotor speeds. Instead of using the classical paradigm defining gaits according to their footfall pattern, we combined the inter-limb coupling and the duty cycle of the stance phase, thus identifying several types of gaits: lateral walk, trot, out-of-phase walk, rotary gallop, transverse gallop, hop, half-bound, and full-bound. Out-of-phase walk, trot, and full-bound were robust and appeared to function as attractor gaits (i.e., a state to which the network flows and stabilizes) at low, intermediate, and high speeds respectively. In contrast, lateral walk, hop, transverse gallop, rotary gallop, and half-bound were more transient and therefore considered transitional gaits (i.e., a labile state of the network from which it flows to the attractor state). Surprisingly, lateral walk was less frequently observed. Using graph analysis, we demonstrated that transitions between gaits were predictable, not random. In summary, the wild-type mouse exhibits a wider repertoire of locomotor gaits than expected. Future locomotor studies should benefit from this paradigm in assessing transgenic mice or wild-type mice with neurotraumatic injury or neurodegenerative disease affecting gait.

Swing Boat: Inducing and Recording Locomotor Activity in a Drosophila melanogaster Model of Alzheimer’s Disease

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Johannes Berlandi

2017-08-01

Full Text Available Recent studies indicate that physical activity can slow down progression of neurodegeneration in humans. To date, automated ways to induce activity have been predominantly described in rodent models. To study the impact of activity on behavior and survival in adult Drosophila melanogaster, we aimed to develop a rotating tube device “swing boat” which is capable of monitoring activity and sleep patterns as well as survival rates of flies. For the purpose of a first application, we tested our device on a transgenic fly model of Alzheimer’s disease (AD. Activity of flies was recorded in a climate chamber using the Drosophila Activity Monitoring (DAM System connected to data acquisition software. Locomotor activity was induced by a rotating tube device “swing boat” by repetitively tilting the tubes for 30 min per day. A non-exercising group of flies was used as control and activity and sleep patterns were obtained. The GAL4-/UAS system was used to drive pan-neuronal expression of human Aβ42 in flies. Immunohistochemical stainings for Aβ42 were performed on paraffin sections of adult fly brains. Daily rotation of the fly tubes evoked a pronounced peak of activity during the 30 min exercise period. Pan-neuronal expression of human Aβ42 in flies caused abnormalities in locomotor activity, reduction of life span and elevated sleep fragmentation in comparison to wild type flies. Furthermore, the formation of amyloid accumulations was observed in the adult fly brain. Gently induced activity over 12 days did not evoke prominent effects in wild type flies but resulted in prolongation of median survival time by 7 days (32.6% in Aβ42-expressing flies. Additionally, restoration of abnormally decreased night time sleep (10% and reduced sleep fragmentation (28% were observed compared to non-exercising Aβ42-expressing flies. On a structural level no prominent effects regarding prevalence of amyloid aggregations and Aβ42 RNA expression were

The anatomy and physiology of the locomotor system.

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Farley, Alistair; McLafferty, Ella; Hendry, Charles

Mobilisation is one of the activities of living. The term locomotor system refers to those body tissues and organs responsible for movement. Nurses and healthcare workers should be familiar with the body structures that enable mobilisation to assist those in their care with this activity. This article outlines the structure and function of the locomotor system, including the skeleton, joints, muscles and muscle attachments. Two common bone disorders, osteoporosis and osteoarthritis, are also considered.

Increased amphetamine-induced locomotor activity, sensitization, and accumbal dopamine release in M5 muscarinic receptor knockout mice

DEFF Research Database (Denmark)

Schmidt, Lene S; Miller, Anthony D; Lester, Deranda B

2010-01-01

showed that M(5) receptor knockout (M (5) (-/-) ) mice are less sensitive to the reinforcing properties of addictive drugs. MATERIALS AND METHODS: Here, we investigate the role of M(5) receptors in the effects of amphetamine and cocaine on locomotor activity, locomotor sensitization, and dopamine release......-induced hyperactivity and dopamine release as well as amphetamine sensitization are enhanced in mice lacking the M(5) receptor. These results support the concept that the M(5) receptor modulates effects of addictive drugs....

Volumetric changes in the aging rat brain and its impact on cognitive and locomotor functions.

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Hamezah, Hamizah Shahirah; Durani, Lina Wati; Ibrahim, Nor Faeizah; Yanagisawa, Daijiro; Kato, Tomoko; Shiino, Akihiko; Tanaka, Sachiko; Damanhuri, Hanafi Ahmad; Ngah, Wan Zurinah Wan; Tooyama, Ikuo

2017-12-01

Impairments in cognitive and locomotor functions usually occur with advanced age, as do changes in brain volume. This study was conducted to assess changes in brain volume, cognitive and locomotor functions, and oxidative stress levels in middle- to late-aged rats. Forty-four male Sprague-Dawley rats were divided into four groups: 14, 18, 23, and 27months of age. 1 H magnetic resonance imaging (MRI) was performed using a 7.0-Tesla MR scanner system. The volumes of the lateral ventricles, medial prefrontal cortex (mPFC), hippocampus, striatum, cerebellum, and whole brain were measured. Open field, object recognition, and Morris water maze tests were conducted to assess cognitive and locomotor functions. Blood was taken for measurements of malondialdehyde (MDA), protein carbonyl content, and antioxidant enzyme activity. The lateral ventricle volumes were larger, whereas the mPFC, hippocampus, and striatum volumes were smaller in 27-month-old rats than in 14-month-old rats. In behavioral tasks, the 27-month-old rats showed less exploratory activity and poorer spatial learning and memory than did the 14-month-old rats. Biochemical measurements likewise showed increased MDA and lower glutathione peroxidase (GPx) activity in the 27-month-old rats. In conclusion, age-related increases in oxidative stress, impairment in cognitive and locomotor functions, and changes in brain volume were observed, with the most marked impairments observed in later age. Copyright © 2017. Published by Elsevier Inc.

The locomotor activity of soccer players based on playing positions during the 2010 World Cup.

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Soroka, Andrzej

2018-06-01

The aim of this study was to define the locomotor activity of footballer players during the 2010 World Cup and to assess what differences existed among different playing positions. Research was conducted using research material collected from the Castrol Performance Index, a kinematic game analysis system that records player movements during a game by use of semi-automatic cameras. A total of 599 players who participated in the championships were analyzed. The results were evaluated using one-way analysis of variance (ANOVA) and a post-hoc test that calculated the Honestly Significant Difference (HSD) in order to determine which mean values significantly differed among the player positions. It was found that midfielders covered on average the largest distance during a match (10,777.6 m, Plocomotor activity at high and sprint intensities (2936.8 m and 108.4 m, respectively). Additionally, midfielders also spent the largest amount of time at performing at a high intensity (10.6%). Strikers also featured high levels of the above parameters; the total length of distance covered with high intensities was found to be on average 2586.7 m, the distance covered at sprint intensity was 105 m. The footballers, playing at the championship level feature excellent locomotor preparation. This fact is undoubtedly supported by the aerobic training of high intensity. Such training allows footballers to extend the distance they cover during the match, increase the intensity of locomotor activities and sprint speed distance.

Locomotor activity and discriminative stimulus effects of a novel series of synthetic cathinone analogs in mice and rats.

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Gatch, Michael B; Dolan, Sean B; Forster, Michael J

2017-04-01

Recent years have seen an increase in the recreational use of novel, synthetic psychoactive substances. There are little or no data on the abuse liability of many of the newer compounds. The current study investigated the discriminative stimulus and locomotor effects of a series of synthetic analogs of cathinone: α-pyrrolidinopropiophenone (α-PPP), α-pyrrolidinohexiophenone (α-PHP), α-pyrrolidinopentiothiophenone (α-PVT), 3,4-methylenedioxybutiophenone (MDPBP), and ethylone. Locomotor activity was assessed in an open-field assay using Swiss-Webster mice. Discriminative stimulus effects were assessed in Sprague-Dawley rats trained to discriminate either cocaine or methamphetamine from vehicle. Each of the compounds produced an inverted-U dose-effect on locomotor activity. Maximal effects were similar among the test compounds, but potencies varied with relative potencies of MDPBP > α-PPP = α-PHP > ethylone > α-PVT. Each of the test compounds substituted fully for the discriminative stimulus effects of methamphetamine. α-PPP, α-PHP, and ethylone fully substituted for cocaine. α-PVT produced a maximum of 50% cocaine-appropriate responding, and MDPBP produced an inverted-U-shaped dose-effect curve with maximum effects of 67%. These data provide initial evidence that these structurally similar, emerging novel psychoactive substances demonstrate potential for abuse and may be utilized for their stimulant-like effects, given their ability to stimulate locomotor activity and their substitution for the discriminative stimulus effects of the classical psychostimulants cocaine and/or methamphetamine.

Distinct sets of locomotor modules control the speed and modes of human locomotion

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Yokoyama, Hikaru; Ogawa, Tetsuya; Kawashima, Noritaka; Shinya, Masahiro; Nakazawa, Kimitaka

2016-01-01

Although recent vertebrate studies have revealed that different spinal networks are recruited in locomotor mode- and speed-dependent manners, it is unknown whether humans share similar neural mechanisms. Here, we tested whether speed- and mode-dependence in the recruitment of human locomotor networks exists or not by statistically extracting locomotor networks. From electromyographic activity during walking and running over a wide speed range, locomotor modules generating basic patterns of muscle activities were extracted using non-negative matrix factorization. The results showed that the number of modules changed depending on the modes and speeds. Different combinations of modules were extracted during walking and running, and at different speeds even during the same locomotor mode. These results strongly suggest that, in humans, different spinal locomotor networks are recruited while walking and running, and even in the same locomotor mode different networks are probably recruited at different speeds. PMID:27805015

The H2O2 scavenger ebselen decreases ethanol-induced locomotor stimulation in mice.

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Ledesma, Juan Carlos; Font, Laura; Aragon, Carlos M G

2012-07-01

In the brain, the enzyme catalase by reacting with H(2)O(2) forms Compound I (catalase-H(2)O(2) system), which is the main system of central ethanol metabolism to acetaldehyde. Previous research has demonstrated that acetaldehyde derived from central-ethanol metabolism mediates some of the psychopharmacological effects produced by ethanol. Manipulations that modulate central catalase activity or sequester acetaldehyde after ethanol administration modify the stimulant effects induced by ethanol in mice. However, the role of H(2)O(2) in the behavioral effects caused by ethanol has not been clearly addressed. The present study investigated the effects of ebselen, an H(2)O(2) scavenger, on ethanol-induced locomotion. Swiss RjOrl mice were pre-treated with ebselen (0-50mg/kg) intraperitoneally (IP) prior to administration of ethanol (0-3.75g/kg; IP). In another experiment, animals were pre-treated with ebselen (0 or 25mg/kg; IP) before caffeine (15mg/kg; IP), amphetamine (2mg/kg; IP) or cocaine (10mg/kg; IP) administration. Following these treatments, animals were placed in an open field to measure their locomotor activity. Additionally, we evaluated the effect of ebselen on the H(2)O(2)-mediated inactivation of brain catalase activity by 3-amino-1,2,4-triazole (AT). Ebselen selectively prevented ethanol-induced locomotor stimulation without altering the baseline activity or the locomotor stimulating effects caused by caffeine, amphetamine and cocaine. Ebselen reduced the ability of AT to inhibit brain catalase activity. Taken together, these data suggest that a decline in H(2)O(2) levels might result in a reduction of the ethanol locomotor-stimulating effects, indicating a possible role for H(2)O(2) in some of the psychopharmacological effects produced by ethanol. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Effects of Resveratrol on Daily Rhythms of Locomotor Activity and Body Temperature in Young and Aged Grey Mouse Lemurs

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Fabien Pifferi

2013-01-01

Full Text Available In several species, resveratrol, a polyphenolic compound, activates sirtuin proteins implicated in the regulation of energy balance and biological clock processes. To demonstrate the effect of resveratrol on clock function in an aged primate, young and aged mouse lemurs (Microcebus murinus were studied over a 4-week dietary supplementation with resveratrol. Spontaneous locomotor activity and daily variations in body temperature were continuously recorded. Reduction in locomotor activity onset and changes in body temperature rhythm in resveratrol-supplemented aged animals suggest an improved synchronisation on the light-dark cycle. Resveratrol could be a good candidate to restore the circadian rhythms in the elderly.

Neuromodulation of the lumbar spinal locomotor circuit.

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AuYong, Nicholas; Lu, Daniel C

2014-01-01

The lumbar spinal cord contains the necessary circuitry to independently drive locomotor behaviors. This function is retained following spinal cord injury (SCI) and is amenable to rehabilitation. Although the effectiveness of task-specific training and pharmacologic modulation has been repeatedly demonstrated in animal studies, results from human studies are less striking. Recently, lumbar epidural stimulation (EDS) along with locomotor training was shown to restore weight-bearing function and lower-extremity voluntary control in a chronic, motor-complete human SCI subject. Related animal studies incorporating EDS as part of the therapeutic regiment are also encouraging. EDS is emerging as a promising neuromodulatory tool for SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

Developing the content of a locomotor disability scale for adults in Bangladesh: a qualitative study.

Science.gov (United States)

Mahmud, Ilias; Clarke, Lynda; Ploubidis, George B

2017-01-01

Bangladesh has an estimated 17 million adults with disabilities. A significant proportion of them are believed to have locomotor disabilities. There are over 300 non-governmental organizations providing different types of rehabilitation services to them. However, there is no locally developed and validated locomotor disability measurement scale in Bangladesh. The purpose of this study was to develop a locomotor disability scale with disability indicators suitable for adults in Bangladesh. Semi-structured interviews were conducted with 25 purposively selected adults with locomotor disabilities to generate scale items. At the second stage, cognitive interviews were conducted with 12 purposively selected adults with locomotor disabilities in order to refine the measurement questions and response categories. Data were analysed using the framework technique- identifying, abstracting, charting and matching themes across the interviews. For a locomotor disability scale, 70 activities (disability indicators) were identified: 37 mobility activities, 9 activities of daily living, 17 work/productivity activities and 7 leisure activities. Cognitive interviews revealed that when asking the respondents to rate their difficulty in performing the activities, instead of just mentioning the activity name, such as taking a bath or shower, a detailed description of the activity and response options were necessary to ensure consistent interpretation of the disability indicators and response options across all respondents. Identifying suitable disability indicators was the first step in developing a locomotor disability scale for adults in Bangladesh. Interviewing adults with locomotor disabilities in Bangladesh ensured that the locomotor disability scale is of relevance to them and consequently it has excellent content validity. Further research is needed to evaluate the psychometric properties of this scale.

Assessment of long-range correlation in animal behavior time series: The temporal pattern of locomotor activity of Japanese quail (Coturnix coturnix) and mosquito larva (Culex quinquefasciatus)

Science.gov (United States)

Kembro, Jackelyn M.; Flesia, Ana Georgina; Gleiser, Raquel M.; Perillo, María A.; Marin, Raul H.

2013-12-01

Detrended Fluctuation Analysis (DFA) is a method that has been frequently used to determine the presence of long-range correlations in human and animal behaviors. However, according to previous authors using statistical model systems, in order to correctly use DFA different aspects should be taken into account such as: (1) the establishment by hypothesis testing of the absence of short term correlation, (2) an accurate estimation of a straight line in the log-log plot of the fluctuation function, (3) the elimination of artificial crossovers in the fluctuation function, and (4) the length of the time series. Taking into consideration these factors, herein we evaluated the presence of long-range correlation in the temporal pattern of locomotor activity of Japanese quail (Coturnix coturnix) and mosquito larva (Culex quinquefasciatus). In our study, modeling the data with the general autoregressive integrated moving average (ARFIMA) model, we rejected the hypothesis of short-range correlations (d=0) in all cases. We also observed that DFA was able to distinguish between the artificial crossover observed in the temporal pattern of locomotion of Japanese quail and the crossovers in the correlation behavior observed in mosquito larvae locomotion. Although the test duration can slightly influence the parameter estimation, no qualitative differences were observed between different test durations.

Regulation by orexin of feeding behaviour and locomotor activity in the goldfish.

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Nakamachi, T; Matsuda, K; Maruyama, K; Miura, T; Uchiyama, M; Funahashi, H; Sakurai, T; Shioda, S

2006-04-01

Orexin is a hypothalamic neuropeptide that is implicated in the regulation of feeding behaviour and the sleep-wakefulness cycle in mammals. However, in spite of a growing body of knowledge concerning orexin in mammals, the orexin system and its function have not been well studied in lower vertebrates. In the present study, we first examined the effect of feeding status on the orexin-like immunoreactivity (orexin-LI) and the expression of orexin mRNA in the goldfish brain. The number of cells showing orexin-LI in the hypothalamus of goldfish brain showed a significant increase in fasted fish and a significant decrease in glucose-injected fish. The expression level of orexin mRNA in the brains of fasted fish increased compared to that of fed fish. We also examined the effect of an i.c.v. injection of orexin or an anti-orexin serum on food intake and locomotor activity in the goldfish. Administration of orexin by i.c.v. injection induced a significant increase of food intake and locomotor activity, whereas i.p. injection of glucose or i.c.v. injection of anti-orexin serum decreased food consumption. These results indicate that the orexin functions as an orexigenic factor in the goldfish brain.

Effect of subacute poisoning with bifenthrin on locomotor activity, memory retention, haematological, biochemical and histopathological parameters in mice.

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Nieradko-Iwanicka, B; Borzecki, A; Jodlowska-Jedrych, B

2015-02-01

Bifenthrin (BIF) is a pyrethroid (PYR) insecticide. The target point for PYR's toxic action are voltage sensitive sodium channels in the central nervous system (CNS). Intoxication with PYRs results in motor activity impairment and death in insects. Although PYRs are considered to be safe for mammals, there were numerous cases of pyrethroid poisoning in humans, animals and pets described. The general population is chronically exposed to PYRs via grain products, dust and indoor air. Therefore new questions arise: whether PYRs act in a dose-additive fashion in the course of subacute poisoning, are there other target organs (but brain) for BIF and if there is one common mechanism of its' toxic action in different organs. The objective of this work was to characterize the effect of BIF at the doses of 4 or 8 mg/kg injected intraperitoneally (i.p.) daily for 28 consecutive days on memory and motor activity, hematological, biochemical and histopathological parameters in mice. BIF at the doses of 8 mg/kg or 4 mg/kg of body mass was administered i.p. daily to the mice for 28 consecutive days. Motor function was measured on day 1, 7, 14 and 28 and memory retention was tested in a passive avoidance task on day 2, 7, 14 and 28. BIF significantly impaired memory retention on day 2. BIF decreased locomotor activity at every stage of the experiment in a single dose depending manner. No behavioral cumulative effect was observed. Subacute poisoning with the higher dose of BIF caused anaemia, elevated white blood cell count (WBC), elevated alanine transaminase (ALT), superoxide dismuthase (SOD), and decreased glutathione peroxidase (GPx) activity. Lymphocyte infiltrates were visualized in the livers. subacute poisoning with BIF decreases locomotor activity in a single dose proportionate manner. BIF damages also the liver and alters blood morphology. The possible common mechanism of these effects can be oxidative stress.

Fundamental motor skill, physical activity, and sedentary behavior in socioeconomically disadvantaged kindergarteners.

Science.gov (United States)

Gu, Xiangli

2016-10-01

Guided by Stodden et al's conceptual model, the main purpose of the study was to examine the relation between fundamental motor skills (FMS; locomotor and objective control skills), different intensity levels of physical activity (light PA [LPA], moderate-to-vigorous PA [MVPA], and vigorous PA[VPA]), and sedentary behavior (SB) in socioeconomically disadvantaged kindergarteners. A prospective design was used in this study and the data were collected across the 2013-2014 academic school year. Participants were 256 (129 boys; 127 girls; Mage = 5.37, SD = 0.48) kindergarteners recruited from three public schools in the southern United States. Results found that FMS were significantly related to LPA, MVPA, VPA, and SB. Regression analyses indicate that locomotor skills explained significant variance for LPA (6.4%; p < .01), MVPA (7.9%; p < .001), and VPA (5.3%; p < .01) after controlling for weight status. Mediational analysis supports the significant indirect effect of MVPA on the relation between FMS and SB (95% CI: [-0.019, -0.006]). Adequate FMS development during early childhood may result in participating in more varied physical activities, thus leading to lower risk of obesity-related behaviors.

Sexual differences in post-hatching Saunders's gulls: size, locomotor activity, and foraging skill.

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Yoon, Jongmin; Lee, Seung-Hee; Joo, Eun-Jin; Na, Ki-Jeong; Park, Shi-Ryong

2013-04-01

Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

Impairment of locomotor activity induced by the novel N-acylhydrazone derivatives LASSBio-785 and LASSBio-786 in mice

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G.A.P. Silva

Full Text Available The N-acylhydrazone (NAH analogues N-methyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-785 and N-benzyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-786 were prepared from 2-thienylidene 3,4-methylenedioxybenzoylhydrazine (LASSBio-294. The ability of LASSBio-785 and LASSBio-786 to decrease central nervous system activity was investigated in male Swiss mice. LASSBio-785 or LASSBio-786 (30 mg/kg, ip reduced locomotor activity from 209 ± 26 (control to 140 ± 18 (P < 0.05 or 146 ± 15 crossings/min (P < 0.05, respectively. LASSBio-785 (15 or 30 mg/kg, iv also reduced locomotor activity from 200 ± 15 to 116 ± 29 (P < 0.05 or 60 ± 16 crossings/min (P < 0.01, respectively. Likewise, LASSBio-786 (15 or 30 mg/kg, iv reduced locomotor activity from 200 ± 15 to 127 ± 10 (P < 0.01 or 96 ± 14 crossings/min (P < 0.01, respectively. Pretreatment with flumazenil (20 mg/kg, ip prevented the locomotor impairment induced by NAH analogues (15 mg/kg, iv, providing evidence that the benzodiazepine (BDZ receptor is involved. This finding was supported by the structural similarity of NAH analogues to midazolam. However, LASSBio-785 showed weak binding to the BDZ receptor. LASSBio-785 or LASSBio-786 (30 mg/kg, ip, n = 10 increased pentobarbital-induced sleeping time from 42 ± 5 (DMSO to 66 ± 6 (P < 0.05 or 75 ± 4 min (P < 0.05, respectively. The dose required to achieve 50% hypnosis (HD50 following iv injection of LASSBio-785 or LASSBio-786 was 15.8 or 9.5 mg/kg, respectively. These data suggest that both NAH analogues might be useful for the development of new neuroactive drugs for the treatment of insomnia or for use in conjunction with general anesthesia.

Impairment of locomotor activity induced by the novel N-acylhydrazone derivatives LASSBio-785 and LASSBio-786 in mice

Energy Technology Data Exchange (ETDEWEB)

Silva, G.A.P. [Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Kummerle, A.E. [Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Antunes, F. [Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Fraga, C.A.M.; Barreiro, E.J. [Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Programa de Pós-Graduação em Química, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Zapata-Sudo, G.; Sudo, R.T. [Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

2013-03-19

The N-acylhydrazone (NAH) analogues N-methyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-785) and N-benzyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-786) were prepared from 2-thienylidene 3,4-methylenedioxybenzoylhydrazine (LASSBio-294). The ability of LASSBio-785 and LASSBio-786 to decrease central nervous system activity was investigated in male Swiss mice. LASSBio-785 or LASSBio-786 (30 mg/kg, ip) reduced locomotor activity from 209 ± 26 (control) to 140 ± 18 (P < 0.05) or 146 ± 15 crossings/min (P < 0.05), respectively. LASSBio-785 (15 or 30 mg/kg, iv) also reduced locomotor activity from 200 ± 15 to 116 ± 29 (P < 0.05) or 60 ± 16 crossings/min (P < 0.01), respectively. Likewise, LASSBio-786 (15 or 30 mg/kg, iv) reduced locomotor activity from 200 ± 15 to 127 ± 10 (P < 0.01) or 96 ± 14 crossings/min (P < 0.01), respectively. Pretreatment with flumazenil (20 mg/kg, ip) prevented the locomotor impairment induced by NAH analogues (15 mg/kg, iv), providing evidence that the benzodiazepine (BDZ) receptor is involved. This finding was supported by the structural similarity of NAH analogues to midazolam. However, LASSBio-785 showed weak binding to the BDZ receptor. LASSBio-785 or LASSBio-786 (30 mg/kg, ip, n = 10) increased pentobarbital-induced sleeping time from 42 ± 5 (DMSO) to 66 ± 6 (P < 0.05) or 75 ± 4 min (P < 0.05), respectively. The dose required to achieve 50% hypnosis (HD{sub 50}) following iv injection of LASSBio-785 or LASSBio-786 was 15.8 or 9.5 mg/kg, respectively. These data suggest that both NAH analogues might be useful for the development of new neuroactive drugs for the treatment of insomnia or for use in conjunction with general anesthesia.

Impairment of locomotor activity induced by the novel N-acylhydrazone derivatives LASSBio-785 and LASSBio-786 in mice

International Nuclear Information System (INIS)

Silva, G.A.P.; Kummerle, A.E.; Antunes, F.; Fraga, C.A.M.; Barreiro, E.J.; Zapata-Sudo, G.; Sudo, R.T.

2013-01-01

The N-acylhydrazone (NAH) analogues N-methyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-785) and N-benzyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-786) were prepared from 2-thienylidene 3,4-methylenedioxybenzoylhydrazine (LASSBio-294). The ability of LASSBio-785 and LASSBio-786 to decrease central nervous system activity was investigated in male Swiss mice. LASSBio-785 or LASSBio-786 (30 mg/kg, ip) reduced locomotor activity from 209 ± 26 (control) to 140 ± 18 (P < 0.05) or 146 ± 15 crossings/min (P < 0.05), respectively. LASSBio-785 (15 or 30 mg/kg, iv) also reduced locomotor activity from 200 ± 15 to 116 ± 29 (P < 0.05) or 60 ± 16 crossings/min (P < 0.01), respectively. Likewise, LASSBio-786 (15 or 30 mg/kg, iv) reduced locomotor activity from 200 ± 15 to 127 ± 10 (P < 0.01) or 96 ± 14 crossings/min (P < 0.01), respectively. Pretreatment with flumazenil (20 mg/kg, ip) prevented the locomotor impairment induced by NAH analogues (15 mg/kg, iv), providing evidence that the benzodiazepine (BDZ) receptor is involved. This finding was supported by the structural similarity of NAH analogues to midazolam. However, LASSBio-785 showed weak binding to the BDZ receptor. LASSBio-785 or LASSBio-786 (30 mg/kg, ip, n = 10) increased pentobarbital-induced sleeping time from 42 ± 5 (DMSO) to 66 ± 6 (P < 0.05) or 75 ± 4 min (P < 0.05), respectively. The dose required to achieve 50% hypnosis (HD 50 ) following iv injection of LASSBio-785 or LASSBio-786 was 15.8 or 9.5 mg/kg, respectively. These data suggest that both NAH analogues might be useful for the development of new neuroactive drugs for the treatment of insomnia or for use in conjunction with general anesthesia

Mouse short- and long-term locomotor activity analyzed by video tracking software.

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York, Jason M; Blevins, Neil A; McNeil, Leslie K; Freund, Gregory G

2013-06-20

Locomotor activity (LMA) is a simple and easily performed measurement of behavior in mice and other rodents. Improvements in video tracking software (VTS) have allowed it to be coupled to LMA testing, dramatically improving specificity and sensitivity when compared to the line crossings method with manual scoring. In addition, VTS enables high-throughput experimentation. While similar to automated video tracking used for the open field test (OFT), LMA testing is unique in that it allows mice to remain in their home cage and does not utilize the anxiogenic stimulus of bright lighting during the active phase of the light-dark cycle. Traditionally, LMA has been used for short periods of time (mins), while longer movement studies (hrs-days) have often used implanted transmitters and biotelemetry. With the option of real-time tracking, long-, like short-term LMA testing, can now be conducted using videography. Long-term LMA testing requires a specialized, but easily constructed, cage so that food and water (which is usually positioned on the cage top) does not obstruct videography. Importantly, videography and VTS allows for the quantification of parameters, such as path of mouse movement, that are difficult or unfeasible to measure with line crossing and/or biotelemetry. In sum, LMA testing coupled to VTS affords a more complete description of mouse movement and the ability to examine locomotion over an extended period of time.

Developmental Deltamethrin Exposure Causes Persistent Changes in Dopaminergic Gene Expression, Neurochemistry, and Locomotor Activity in Zebrafish.

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Kung, Tiffany S; Richardson, Jason R; Cooper, Keith R; White, Lori A

2015-08-01

Pyrethroids are commonly used insecticides that are considered to pose little risk to human health. However, there is an increasing concern that children are more susceptible to the adverse effects of pesticides. We used the zebrafish model to test the hypothesis that developmental exposure to low doses of the pyrethroid deltamethrin results in persistent alterations in dopaminergic gene expression, neurochemistry, and locomotor activity. Zebrafish embryos were treated with deltamethrin (0.25-0.50 μg/l), at concentrations below the LOAEL, during the embryonic period [3-72 h postfertilization (hpf)], after which transferred to fresh water until the larval stage (2-weeks postfertilization). Deltamethrin exposure resulted in decreased transcript levels of the D1 dopamine (DA) receptor (drd1) and increased levels of tyrosine hydroxylase at 72 hpf. The reduction in drd1 transcripts persisted to the larval stage and was associated with decreased D2 dopamine receptor transcripts. Larval fish, exposed developmentally to deltamethrin, had increased levels of homovanillic acid, a DA metabolite. Since the DA system is involved in locomotor activity, we measured the swim activity of larval fish following a transition to darkness. Developmental exposure to deltamethrin significantly increased larval swim activity which was attenuated by concomitant knockdown of the DA transporter. Acute exposure to methylphenidate, a DA transporter inhibitor, increased swim activity in control larva, while reducing swim activity in larva developmentally exposed to deltamethrin. Developmental exposure to deltamethrin causes locomotor deficits in larval zebrafish, which is likely mediated by dopaminergic dysfunction. This highlights the need to understand the persistent effects of low-dose neurotoxicant exposure during development. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Catalase inhibition in the Arcuate nucleus blocks ethanol effects on the locomotor activity of rats.

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Sanchis-Segura, Carles; Correa, Mercé; Miquel, Marta; Aragon, Carlos M G

2005-03-07

Previous studies have demonstrated that there is a bidirectional modulation of ethanol-induced locomotion produced by drugs that regulate brain catalase activity. In the present study we have assessed the effect in rats of intraperitoneal, intraventricular or intracraneal administration of the catalase inhibitor sodium azide in the locomotor changes observed after ethanol (1 g/kg) administration. Our results show that sodium azide prevents the effects of ethanol in rats locomotion not only when sodium azide was systemically administered but also when it was intraventricularly injected, then confirming that the interaction between catalase and ethanol takes place in Central Nervous System (CNS). Even more interestingly, the same results were observed when sodium azide administration was restricted to the hypothalamic Arcuate nucleus (ARC), a brain region which has one of the highest levels of expression of catalase. Therefore, the results of the present study not only confirm a role for brain catalase in the mediation of ethanol-induced locomotor changes in rodents but also point to the ARC as a major neuroanatomical location for this interaction. These results are in agreement with our reports showing that ethanol-induced locomotor changes are clearly dependent of the ARC integrity and, especially of the POMc-synthesising neurons of this nucleus. According to these data we propose a model in which ethanol oxidation via catalase could produce acetaldehyde into the ARC and to promote a release of beta-endorphins that would activate opioid receptors to produce locomotion and other ethanol-induced neurobehavioural changes.

CRFR1 in the ventromedial caudate putamen modulates acute stress-enhanced expression of cocaine locomotor sensitization.

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Liu, Shuli; Wang, Zhiyan; Li, Yijing; Sun, Xiaowei; Ge, Feifei; Yang, Mingda; Wang, Xinjuan; Wang, Na; Wang, Junkai; Cui, Cailian

2017-07-15

Repeated exposure to psychostimulants induces a long-lasting enhancement of locomotor activity called behavioral sensitization, which is often reinforced by stress after drug withdrawal. The mechanisms underlying these phenomena remain elusive. Here we explored the effects of acute stress 3 or 14 days after the cessation of chronic cocaine treatment on the expression of locomotor sensitization induced by a cocaine challenge in rats and the key brain region and molecular mechanism underlying the phenomenon. A single session of forced swimming, as an acute stress (administered 2 days after the cessation of cocaine), significantly enhanced the expression of cocaine locomotor sensitization 14 days after the final cocaine injection (challenge at 12 days after acute stress) but not 3 days after the cessation of cocaine (challenge at 1 day after acute stress). The result indicated that acute stress enhanced the expression of cocaine locomotor sensitization after incubation for 12 days rather than 1 day after the last cocaine injection. Moreover, the enhancement in locomotor sensitization was paralleled by a selective increase in the number of the c-Fos + cells, the level of CRFR1 mRNA in the ventromedial caudate putamen (vmCPu). Furthermore, the enhancement was significantly attenuated by CRFR1 antagonist NBI-27914 into the vmCPu, implying that the up-regulation of CRFR1 in the vmCPu seems to be critical in the acute stress-enhanced expression of cocaine locomotor sensitization. The findings demonstrate that the long-term effect of acute stress on the expression of cocaine locomotor sensitization is partially mediated by CRFR1 in the vmCPu. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Role of spared pathways in locomotor recovery after body-weight-supported treadmill training in contused rats.

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Singh, Anita; Balasubramanian, Sriram; Murray, Marion; Lemay, Michel; Houle, John

2011-12-01

Body-weight-supported treadmill training (BWSTT)-related locomotor recovery has been shown in spinalized animals. Only a few animal studies have demonstrated locomotor recovery after BWSTT in an incomplete spinal cord injury (SCI) model, such as contusion injury. The contribution of spared descending pathways after BWSTT to behavioral recovery is unclear. Our goal was to evaluate locomotor recovery in contused rats after BWSTT, and to study the role of spared pathways in spinal plasticity after BWSTT. Forty-eight rats received a contusion, a transection, or a contusion followed at 9 weeks by a second transection injury. Half of the animals in the three injury groups were given BWSTT for up to 8 weeks. Kinematics and the Basso-Beattie-Bresnahan (BBB) test assessed behavioral improvements. Changes in Hoffmann-reflex (H-reflex) rate depression property, soleus muscle mass, and sprouting of primary afferent fibers were also evaluated. BWSTT-contused animals showed accelerated locomotor recovery, improved H-reflex properties, reduced muscle atrophy, and decreased sprouting of small caliber afferent fibers. BBB scores were not improved by BWSTT. Untrained contused rats that received a transection exhibited a decrease in kinematic parameters immediately after the transection; in contrast, trained contused rats did not show an immediate decrease in kinematic parameters after transection. This suggests that BWSTT with spared descending pathways leads to neuroplasticity at the lumbar spinal level that is capable of maintaining locomotor activity. Discontinuing training after the transection in the trained contused rats abolished the improved kinematics within 2 weeks and led to a reversal of the improved H-reflex response, increased muscle atrophy, and an increase in primary afferent fiber sprouting. Thus continued training may be required for maintenance of the recovery. Transected animals had no effect of BWSTT, indicating that in the absence of spared pathways this

Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats.

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Adriaan W Bruijnzeel

Full Text Available Cannabis is the most widely used illicit drug in the world. Delta-9-tetrahydrocannabinol (Δ9-THC is the main psychoactive component of cannabis and its effects have been well-studied. However, cannabis contains many other cannabinoids that affect brain function. Therefore, these studies investigated the effect of cannabis smoke exposure on locomotor activity, rearing, anxiety-like behavior, and the development of dependence in rats. It was also investigated if cannabis smoke exposure leads to tolerance to the locomotor-suppressant effects of the endogenous cannabinoid anandamide. Cannabis smoke was generated by burning 5.7% Δ9-THC cannabis cigarettes in a smoking machine. The effect of cannabis smoke on the behavior of rats in a small and large open field and an elevated plus maze was evaluated. Cannabis smoke exposure induced a brief increase in locomotor activity followed by a prolonged decrease in locomotor activity and rearing in the 30-min small open field test. The cannabinoid receptor type 1 (CB1 receptor antagonist rimonabant increased locomotor activity and prevented the smoke-induced decrease in rearing. Smoke exposure also increased locomotor activity in the 5-min large open field test and the elevated plus maze test. The smoke exposed rats spent more time in the center zone of the large open field, which is indicative of a decrease in anxiety-like behavior. A high dose of anandamide decreased locomotor activity and rearing in the small open field and this was not prevented by rimonabant or pre-exposure to cannabis smoke. Serum Δ9-THC levels were 225 ng/ml after smoke exposure, which is similar to levels in humans after smoking cannabis. Exposure to cannabis smoke led to dependence as indicated by more rimonabant-precipitated somatic withdrawal signs in the cannabis smoke exposed rats than in the air-control rats. In conclusion, chronic cannabis smoke exposure in rats leads to clinically relevant Δ9-THC levels, dependence, and has

Tributyltin induces premature hatching and reduces locomotor activity in zebrafish (Danio rerio) embryos/larvae at environmentally relevant levels.

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Liang, Xuefang; Souders, Christopher L; Zhang, Jiliang; Martyniuk, Christopher J

2017-12-01

Tributyltin (TBT) is an organotin compound that is the active ingredient of many biocides and antifouling agents. In addition to its well established role as an endocrine disruptor, TBT is also associated with adverse effects on the nervous system and behavior. In this study, zebrafish (Danio rerio) embryos were exposed to environmentally relevant concentrations of TBT (0.01, 0.1, 1 nM) to determine how low levels affected development and behavior. Fish exposed to 1 nM TBT hatched earlier when compared to controls. Following a 96-h exposure, total swimming distance, velocity, and activity of zebrafish larvae were reduced compared to controls. To identify putative mechanisms for these altered endpoints, we assessed embryo bioenergetics and gene expression. We reasoned that the accelerated hatch time could be related to ATP production and energy, thus embryos were exposed to TBT for 24 and 48-h exposure prior to hatch. There were no differences among groups for endpoints related to bioenergetics (i.e. basal, ATP-dependent, and maximal respiration). To address mechanisms related to changes in behavioral activity, we measured transcripts associated with muscle function (myf6, myoD, and myoG) and dopamine signaling (th, dat, dopamine receptors) as dopamine regulates behavior. No transcript was altered in expression by TBT in larvae, suggesting that other mechanisms exist that may explain changes in higher level endpoints. These results suggest that endpoints related to the whole animal (i.e. timing of hatch and locomotor behavior) are more sensitive to environmentally-relevant concentrations of TBT compared to the molecular and metabolic endpoints examined here. Copyright © 2017 Elsevier Ltd. All rights reserved.

Oxytocin decreases cocaine taking, cocaine seeking, and locomotor activity in female rats

OpenAIRE

Leong, Kah-Chung; Zhou, Luyi; Ghee, Shannon M.; See, Ronald E.; Reichel, Carmela M.

2016-01-01

Oxytocin has been shown to decrease cocaine taking and seeking in male rats, suggesting potential treatment efficacy for drug addiction. In the present study, we extended these findings to the assessment of cocaine seeking and taking in female rats. Further, we made direct comparisons of oxytocin’s impact on cocaine induced locomotor activity in both males and females. In females, systemic oxytocin (0.3, 1.0, 3.0 mg/kg) attenuated lever pressing for cocaine during self-administration and oxyt...

Novelty response and 50 kHz ultrasonic vocalizations: Differential prediction of locomotor and affective response to amphetamine in Sprague-Dawley rats.

Science.gov (United States)

Garcia, Erik J; Cain, Mary E

2016-02-01

Novelty and sensation seeking (NSS) predisposes humans and rats to experiment with psychostimulants. In animal models, different tests of NSS predict different phases of drug dependence. Ultrasonic vocalizations (USVs) are evoked by psychomotor stimulants and measure the affective/motivation response to stimuli, yet the role NSS has on USVs in response to amphetamine is not determined. The aim of the present study was to determine if individual differences in NSS and USVs can predict locomotor and USV response to amphetamine (0.0, 0.3, and 1.0 mg/kg) after acute and chronic exposure. Thirty male rats were tested for their response to novelty (IEN), choice to engage in novelty (NPP), and heterospecific play (H-USV). Rats were administered non-contingent amphetamine or saline for seven exposures, and USVs and locomotor activity were measured. After a 14-day rest, rats were administered a challenge dose of amphetamine. Regression analyses indicated that amphetamine dose-dependently increased locomotor activity and the NPP test negatively predicted treatment-induced locomotor activity. The H-USV test predicted treatment-induced frequency-modulated (FM) USVs, but the strength of prediction depended on IEN response. Results provide evidence that locomotor activity and FM USVs induced by amphetamine represent different behavioral responses. The prediction of amphetamine-induced FM USVs by the H-USV screen was changed by the novelty response, indicating that the affective value of amphetamine-measured by FM USVs-depends on novelty response. This provides evidence that higher novelty responders may develop a tolerance faster and may escalate intake faster.

Comprehensive behavioral analysis of pituitary adenylate cyclase-activating polypeptide (PACAP knockout mice

Directory of Open Access Journals (Sweden)

Satoko eHattori

2012-10-01

Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP is a neuropeptide acting as a neurotransmitter, neuromodulator, or neurotrophic factor. PACAP is widely expressed throughout the brain and exerts its functions through the PACAP-specific receptor (PAC1. Recent studies reveal that genetic variants of the PACAP and PAC1 genes are associated with mental disorders, and several behavioral abnormalities of PACAP knockout (KO mice are reported. However, an insufficient number of backcrosses was made using PACAP KO mice on the C57BL/6J background due to their postnatal mortality. To elucidate the effects of PACAP on neuropsychiatric function, the PACAP gene was knocked out in F1 hybrid mice (C57BL/6J x 129SvEv for appropriate control of the genetic background. The PACAP KO mice were then subjected to a behavioral test battery. PACAP deficiency had no significant effects on neurological screen. As shown previously, the mice exhibited significantly increased locomotor activity in a novel environment and abnormal anxiety-like behavior, while no obvious differences between genotypes were shown in home cage activity. In contrast to previous reports, the PACAP KO mice showed normal prepulse inhibition and slightly decreased depression-like behavior. Previous study demonstrates that the social interaction in a resident-intruder test was decreased in PACAP KO mice. On the other hand, we showed that PACAP KO mice exhibited increased social interaction in Crawley’s three-chamber social approach test, although PACAP KO had no significant impact on social interaction in a home cage. PACAP KO mice also exhibited mild performance deficit in working memory in an eight-arm radial maze and the T-maze, while they did not show any significant abnormalities in the left-right discrimination task in the T-maze. These results suggest that PACAP has an important role in the regulation of locomotor activity, social behavior, anxiety-like behavior and, potentially

Astrocytic IL-6 mediates locomotor activity, exploration, anxiety, learning and social behavior.

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Erta, Maria; Giralt, Mercedes; Esposito, Flavia Lorena; Fernandez-Gayol, Olaya; Hidalgo, Juan

2015-07-01

Interleukin-6 (IL-6) is a major cytokine in the central nervous system, secreted by different brain cells and with roles in a number of physiological functions. We herewith confirm and expand the importance of astrocytic production of and response to IL-6 by using transgenic mice deficient in astrocytic IL-6 (Ast-IL-6 KO) or in its receptor (Ast-IL-6R KO) in full C57Bl/6 genetic background. A major prosurvival effect of astrocytic IL-6 at early ages was clearly demonstrated. Robust effects were also evident in the control of activity and anxiety in the hole-board and elevated plus-maze, and in spatial learning in the Morris water-maze. The results also suggest an inhibitory role of IL-6 in the mechanism controlling the consolidation of hippocampus-dependent spatial learning. Less robust effects of astrocytic IL-6 system were also observed in despair behavior in the tail suspension test, and social behavior in the dominance and resident-intruder tests. The behavioral phenotype was highly dependent on age and/or sex in some cases. The phenotype of Ast-IL-6R KO mice mimicked only partially that of Ast-IL-6KO mice, which indicates both a role of astrocytes in behavior and the participation of other cells besides astrocytes. No evidences of altered function of the hypothalamic-pituitary-adrenal axis were observed. These results demonstrate that astrocytic IL-6 (acting at least partially in astrocytes) regulates normal behavior in mice. Copyright © 2015 Elsevier Inc. All rights reserved.

Quaternary naltrexone reverses radiogenic and morphine-induced locomotor hyperactivity

Energy Technology Data Exchange (ETDEWEB)

Mickley, G.A.; Stevens, K.E.; Galbraith, J.A.; White, G.A.; Gibbs, G.L.

1984-04-01

The present study attempted to determine the relative role of the peripheral and central nervous system in the production of morphine-induced or radiation-induced locomotor hyperactivity of the mouse. Toward this end, we used a quaternary derivative of an opiate antagonist (naltrexone methobromide), which presumably does not cross the blood-brain barrier. Quaternary naltrexone was used to challenge the stereotypic locomotor response observed in these mice after either an i.p. injection of morphine or exposure to 1500 rads /sup 60/Co. The quaternary derivative of naltrexone reversed the locomotor hyperactivity normally observed in the C57BL/6J mouse after an injection of morphine. It also significantly attenuated radiation-induced locomotion. The data reported here support the hypothesis of endorphin involvement in radiation-induced and radiogenic behaviors. However, these conclusions are contingent upon further research which more fully evaluates naltrexone methobromide's capacity to cross the blood-brain barrier.

Hepatic mTORC1 controls locomotor activity, body temperature, and lipid metabolism through FGF21

Science.gov (United States)

Cornu, Marion; Oppliger, Wolfgang; Albert, Verena; Robitaille, Aaron M.; Trapani, Francesca; Quagliata, Luca; Fuhrer, Tobias; Sauer, Uwe; Terracciano, Luigi; Hall, Michael N.

2014-01-01

The liver is a key metabolic organ that controls whole-body physiology in response to nutrient availability. Mammalian target of rapamycin (mTOR) is a nutrient-activated kinase and central controller of growth and metabolism that is negatively regulated by the tumor suppressor tuberous sclerosis complex 1 (TSC1). To investigate the role of hepatic mTOR complex 1 (mTORC1) in whole-body physiology, we generated liver-specific Tsc1 (L-Tsc1 KO) knockout mice. L-Tsc1 KO mice displayed reduced locomotor activity, body temperature, and hepatic triglyceride content in a rapamycin-sensitive manner. Ectopic activation of mTORC1 also caused depletion of hepatic and plasma glutamine, leading to peroxisome proliferator–activated receptor γ coactivator-1α (PGC-1α)–dependent fibroblast growth factor 21 (FGF21) expression in the liver. Injection of glutamine or knockdown of PGC-1α or FGF21 in the liver suppressed the behavioral and metabolic defects due to mTORC1 activation. Thus, mTORC1 in the liver controls whole-body physiology through PGC-1α and FGF21. Finally, mTORC1 signaling correlated with FGF21 expression in human liver tumors, suggesting that treatment of glutamine-addicted cancers with mTOR inhibitors might have beneficial effects at both the tumor and whole-body level. PMID:25082895

Conditioned place preference and locomotor activity in response to methylphenidate, amphetamine and cocaine in mice lacking dopamine D4 receptors

Energy Technology Data Exchange (ETDEWEB)

Thanos, P.K.; Thanos, P.K.; Bermeo, C.; Rubinstein, M.; Suchland, K.L.; Wang, G.-J.; Grandy, D.K.; Volkow, N.D.

2010-05-01

Methylphenidate (MP) and amphetamine (AMPH) are the most frequently prescribed medications for the treatment of attention-deficit/hyperactivity disorder (ADHD). Both drugs are believed to derive their therapeutic benefit by virtue of their dopamine (DA)-enhancing effects, yet an explanation for the observation that some patients with ADHD respond well to one medication but not to the other remains elusive. The dopaminergic effects of MP and AMPH are also thought to underlie their reinforcing properties and ultimately their abuse. Polymorphisms in the human gene that codes for the DA D4 receptor (D4R) have been repeatedly associated with ADHD and may correlate with the therapeutic as well as the reinforcing effects of responses to these psychostimulant medications. Conditioned place preference (CPP) for MP, AMPH and cocaine were evaluated in wild-type (WT) mice and their genetically engineered littermates, congenic on the C57Bl/6J background, that completely lack D4Rs (knockout or KO). In addition, the locomotor activity in these mice during the conditioning phase of CPP was tested in the CPP chambers. D4 receptor KO and WT mice showed CPP and increased locomotor activity in response to each of the three psychostimulants tested. D4R differentially modulates the CPP responses to MP, AMPH and cocaine. While the D4R genotype affected CPP responses to MP (high dose only) and AMPH (low dose only) it had no effects on cocaine. Inasmuch as CPP is considered an indicator of sensitivity to reinforcing responses to drugs these data suggest a significant but limited role of D4Rs in modulating conditioning responses to MP and AMPH. In the locomotor test, D4 receptor KO mice displayed attenuated increases in AMPH-induced locomotor activity whereas responses to cocaine and MP did not differ. These results suggest distinct mechanisms for D4 receptor modulation of the reinforcing (perhaps via attenuating dopaminergic signalling) and locomotor properties of these stimulant drugs

Mechanisms of Left-Right Coordination in Mammalian Locomotor Pattern Generation Circuits: A Mathematical Modeling View

Science.gov (United States)

Talpalar, Adolfo E.; Rybak, Ilya A.

2015-01-01

The locomotor gait in limbed animals is defined by the left-right leg coordination and locomotor speed. Coordination between left and right neural activities in the spinal cord controlling left and right legs is provided by commissural interneurons (CINs). Several CIN types have been genetically identified, including the excitatory V3 and excitatory and inhibitory V0 types. Recent studies demonstrated that genetic elimination of all V0 CINs caused switching from a normal left-right alternating activity to a left-right synchronized “hopping” pattern. Furthermore, ablation of only the inhibitory V0 CINs (V0D subtype) resulted in a lack of left-right alternation at low locomotor frequencies and retaining this alternation at high frequencies, whereas selective ablation of the excitatory V0 neurons (V0V subtype) maintained the left–right alternation at low frequencies and switched to a hopping pattern at high frequencies. To analyze these findings, we developed a simplified mathematical model of neural circuits consisting of four pacemaker neurons representing left and right, flexor and extensor rhythm-generating centers interacting via commissural pathways representing V3, V0D, and V0V CINs. The locomotor frequency was controlled by a parameter defining the excitation of neurons and commissural pathways mimicking the effects of N-methyl-D-aspartate on locomotor frequency in isolated rodent spinal cord preparations. The model demonstrated a typical left-right alternating pattern under control conditions, switching to a hopping activity at any frequency after removing both V0 connections, a synchronized pattern at low frequencies with alternation at high frequencies after removing only V0D connections, and an alternating pattern at low frequencies with hopping at high frequencies after removing only V0V connections. We used bifurcation theory and fast-slow decomposition methods to analyze network behavior in the above regimes and transitions between them. The model

Effects of short-term fasting on stress physiology, body condition, and locomotor activity in wintering male white-crowned sparrows.

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Krause, Jesse S; Pérez, Jonathan H; Meddle, Simone L; Wingfield, John C

2017-08-01

For wild free-living animals the availability of food resources can be greatly affected by environmental perturbations such as weather events. In response to environmental perturbations, animals activate the hypothalamic-pituitary-adrenal (HPA) axis to adjust physiology and behavior. The literature asserts that during weather events food intake declines leading to changes in HPA axis activity, as measured by both baseline and stress-induced glucocorticoid concentrations. Here we investigated how body condition, locomotor activity, and stress physiology were affected by varying lengths of a fast (1, 2, 6, and 24h; similar to that experienced by free-living birds) compared to when food was provided ad libitum in captive wintering male white-crowned sparrows, Zonotrichia leucophrys gambelii, exposed to a short day photoperiod. Baseline corticosterone concentrations were increased for all fasting durations but were highest in 6 and 24h fasted birds. Stress-induced corticosterone was elevated in 1h fasted birds with a trend for the 2h of fast; no other differences were found. Baseline corticosterone concentrations were negatively related to both total fat scores and body mass. All birds lost body mass regardless of fast length but birds fasted for 24h lost the most. Fat scores declined in the 6 and 24h groups, and no measureable changes were detected in pectoralis muscle profile. Locomotor activity was increased over the entire period in which food was removed regardless of fasting duration. Together this suggests that reduced food availability is responsible, at least in part, for the rapid elevation both baseline corticosterone under any duration of fast and stress-induced concentrations during short-term fasts. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Distribution of networks generating and coordinating locomotor activity in the neonatal rat spinal cord in vitro: a lesion study

DEFF Research Database (Denmark)

Kjaerulff, O; Kiehn, O

1996-01-01

The isolated spinal cord of the newborn rat contains networks that are able to create a patterned motor output resembling normal locomotor movements. In this study, we sought to localize the regions of primary importance for rhythm and pattern generation using specific mechanical lesions. We used...... ventral root recordings to monitor neuronal activity and tested the ability of various isolated parts of the caudal thoraciclumbar cord to generate rhythmic bursting in a combination of 5-HT and NMDA. In addition, pathways mediating left/right and rostrocaudal burst alternation were localized. We found......, these pathways were distributed along the lumbar enlargement. Both lateral and ventral funiculi were sufficient to coordinate activity in the rostral and caudal regions. We conclude that the networks organizing locomotor-related activity in the spinal cord of the newborn rat are distributed....

Attenuated food anticipatory activity and abnormal circadian locomotor rhythms in Rgs16 knockdown mice.

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Naoto Hayasaka

Full Text Available Regulators of G protein signaling (RGS are a multi-functional protein family, which functions in part as GTPase-activating proteins (GAPs of G protein α-subunits to terminate G protein signaling. Previous studies have demonstrated that the Rgs16 transcripts exhibit robust circadian rhythms both in the suprachiasmatic nucleus (SCN, the master circadian light-entrainable oscillator (LEO of the hypothalamus, and in the liver. To investigate the role of RGS16 in the circadian clock in vivo, we generated two independent transgenic mouse lines using lentiviral vectors expressing short hairpin RNA (shRNA targeting the Rgs16 mRNA. The knockdown mice demonstrated significantly shorter free-running period of locomotor activity rhythms and reduced total activity as compared to the wild-type siblings. In addition, when feeding was restricted during the daytime, food-entrainable oscillator (FEO-driven elevated food-anticipatory activity (FAA observed prior to the scheduled feeding time was significantly attenuated in the knockdown mice. Whereas the restricted feeding phase-advanced the rhythmic expression of the Per2 clock gene in liver and thalamus in the wild-type animals, the above phase shift was not observed in the knockdown mice. This is the first in vivo demonstration that a common regulator of G protein signaling is involved in the two separate, but interactive circadian timing systems, LEO and FEO. The present study also suggests that liver and/or thalamus regulate the food-entrained circadian behavior through G protein-mediated signal transduction pathway(s.

Differential housing and novelty response: Protection and risk from locomotor sensitization.

Science.gov (United States)

Garcia, Erik J; Haddon, Tara N; Saucier, Donald A; Cain, Mary E

2017-03-01

High novelty seeking increases the risk for drug experimentation and locomotor sensitization. Locomotor sensitization to psychostimulants is thought to reflect neurological adaptations that promote the transition to compulsive drug taking. Rats reared in enrichment (EC) show less locomotor sensitization when compared to rats reared in isolation (IC) or standard conditions (SC). The current research study was designed to test if novelty response contributed locomotor sensitization and more importantly, if the different housing environments could change the novelty response to protect against the development of locomotor sensitization in both adolescence and adulthood. Experiment 1: rats were tested for their response to novelty using the inescapable novelty test (IEN) and pseudorandomly assigned to enriched (EC), isolated (IC), or standard (SC) housing conditions for 30days. After housing, they were tested with IEN. Rats were then administered amphetamine (0.5mg/kg) or saline and locomotor activity was measured followed by a sensitization test 14days later. Experiment 2: rats were tested in the IEN test early adulthood and given five administrations of amphetamine (0.3mg/kg) or saline and then either stayed in or switched housing environments for 30days. Rats were then re-tested in the IEN test in late adulthood and administered five more injections of their respective treatments and tested for locomotor sensitization. Results indicate that IC and SC increased the response to novelty. EC housing decreased locomotor response to amphetamine and saline, and SC housing increased the locomotor response to amphetamine. Mediation results indicated that the late adult novelty response fully mediates the locomotor response to amphetamine and saline, while the early adulthood novelty response did not. Differential housing changes novelty and amphetamine locomotor response. Novelty response is altered into adulthood and provides evidence that enrichment can be used to reduce

Diurnal changes in core body temperature, day/night locomotor activity patterns, and actigraphy-generated behavioral sleep in aged canines with varying levels of cognitive dysfunction

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Brian M. Zanghi

2016-10-01

Full Text Available Core body temperature (CBT rhythm, locomotor activity, and actigraphy-sleep were evaluated in geriatric dogs with cognitive dysfunction. Dogs (n=33; 9–16 yrs performed a spatial working memory task and divided into three memory groups: Low, Moderate, and High, with subsequent evaluation of learning and attention. Rectal CBT was recorded 6 times over a 17.5 h period and Actiwatch® activity monitoring system for 5 days while housed indoors with 12 h light/dark schedule. Rhythm of daily activity data was evaluated using the traditional cosinor analysis and generation of non-parametric measures of interdaily stability, intradaily variability, and relative amplitude. CBT differed with time (F (5, 130=11.36, p<0.001, and was the highest at 19:00C. CBT at 19:00 was positively related (p<0.01 to memory (r(31=0.50 and 3-domain cognitive performance index (memory, learning, attention; r(31=0.39. Total daytime or night-time activity did not differ between memory groups, but hourly counts at 8:00 were positively related (p<0.05 to memory (r(31=0.52, learning (r(31=0.36, and 3-domain cognitive performance index (r(31=0.53. There were no significant differences between age or memory groups for any circadian rhythm measures. Daytime naps were inversely related to memory accuracy (r(31=−0.39; p<0.05 and BT at 15:00 (r(30=−0.51; p<0.01. Lower peak BT and increased napping may predict some aspects of cognitive performance of working memory, learning, and/or attention processes in these geriatric dogs, but minimal diurnal rhythm disruption of locomotor activity is observed when these cognitive processes decline.

Delineating the Diversity of Spinal Interneurons in Locomotor Circuits.

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Gosgnach, Simon; Bikoff, Jay B; Dougherty, Kimberly J; El Manira, Abdeljabbar; Lanuza, Guillermo M; Zhang, Ying

2017-11-08

Locomotion is common to all animals and is essential for survival. Neural circuits located in the spinal cord have been shown to be necessary and sufficient for the generation and control of the basic locomotor rhythm by activating muscles on either side of the body in a specific sequence. Activity in these neural circuits determines the speed, gait pattern, and direction of movement, so the specific locomotor pattern generated relies on the diversity of the neurons within spinal locomotor circuits. Here, we review findings demonstrating that developmental genetics can be used to identify populations of neurons that comprise these circuits and focus on recent work indicating that many of these populations can be further subdivided into distinct subtypes, with each likely to play complementary functions during locomotion. Finally, we discuss data describing the manner in which these populations interact with each other to produce efficient, task-dependent locomotion. Copyright © 2017 the authors 0270-6474/17/3710835-07$15.00/0.

Evidence for a role of orexin/hypocretin system in vestibular lesion-induced locomotor abnormalities in rats

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Leilei Pan

2016-07-01

Full Text Available Vestibular damage can induce locomotor abnormalities in both animals and humans. Rodents with bilateral vestibular loss showed vestibular deficits syndrome such as circling, opisthotonus as well as locomotor and exploratory hyperactivity. Previous studies have investigated the changes in the dopamine system after vestibular loss, but the results are inconsistent and inconclusive. Numerous evidences indicate that the orexin system is implicated in central motor control. We hypothesized that orexin may be potentially involved in vestibular loss-induced motor disorders. In this study, we examined the effects of arsanilate- or 3, 3′-iminodipropionitrile (IDPN-induced vestibular lesion (AVL or IVL on the orexin-A (OXA labeling in rat hypothalamus using immunohistochemistry. The vestibular lesion-induced locomotor abnormalities were recorded and verified using a histamine H4 receptor antagonist JNJ7777120 (20 mg/kg, i.p.. The effects of the orexin receptor type 1 antagonist SB334867 (16 μg, i.c.v. on these behavior responses were also investigated. At 72 h post-AVL and IVL, animals exhibited vestibular deficit syndrome and locomotor hyperactivity in the home cages. These responses were significantly alleviated by JNJ7777120 which also eliminated AVL-induced increases in exploratory behavior in an open field. The numbers of OXA-labeled neurons in the hypothalamus were significantly increased in the AVL animals at 72 h post-AVL and in the IVL animals at 24, 48 and 72 h post-IVL. SB334867 significantly attenuated the vestibular deficit syndrome and locomotor hyperactivity at 72 h post-AVL and IVL. It also decreased exploratory behavior in the AVL animals. These results suggested that the alteration of OXA expression might contribute to locomotor abnormalities after acute vestibular lesion. The orexin receptors might be the potential therapeutic targets for vestibular disorders.

Neuronal activity in the isolated mouse spinal cord during spontaneous deletions in fictive locomotion: insights into locomotor central pattern generator organization

Science.gov (United States)

Zhong, Guisheng; Shevtsova, Natalia A; Rybak, Ilya A; Harris-Warrick, Ronald M

2012-01-01

We explored the organization of the spinal central pattern generator (CPG) for locomotion by analysing the activity of spinal interneurons and motoneurons during spontaneous deletions occurring during fictive locomotion in the isolated neonatal mouse spinal cord, following earlier work on locomotor deletions in the cat. In the isolated mouse spinal cord, most spontaneous deletions were non-resetting, with rhythmic activity resuming after an integer number of cycles. Flexor and extensor deletions showed marked asymmetry: flexor deletions were accompanied by sustained ipsilateral extensor activity, whereas rhythmic flexor bursting was not perturbed during extensor deletions. Rhythmic activity on one side of the cord was not perturbed during non-resetting spontaneous deletions on the other side, and these deletions could occur with no input from the other side of the cord. These results suggest that the locomotor CPG has a two-level organization with rhythm-generating (RG) and pattern-forming (PF) networks, in which only the flexor RG network is intrinsically rhythmic. To further explore the neuronal organization of the CPG, we monitored activity of motoneurons and selected identified interneurons during spontaneous non-resetting deletions. Motoneurons lost rhythmic synaptic drive during ipsilateral deletions. Flexor-related commissural interneurons continued to fire rhythmically during non-resetting ipsilateral flexor deletions. Deletion analysis revealed two classes of rhythmic V2a interneurons. Type I V2a interneurons retained rhythmic synaptic drive and firing during ipsilateral motor deletions, while type II V2a interneurons lost rhythmic synaptic input and fell silent during deletions. This suggests that the type I neurons are components of the RG, whereas the type II neurons are components of the PF network. We propose a computational model of the spinal locomotor CPG that reproduces our experimental results. The results may provide novel insights into the

Exposição repetida à cafeína aumenta a atividade locomotora induzida pelo femproporex em ratos adolescentes e adultos Repeated administration of caffeine increases femproporex-induced locomotor activity in adolescent and adult rats

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Ana Helena Paro

2008-09-01

Full Text Available A cafeína e o femproporex são substâncias psicoestimulantes. O femproporex é muito utilizado no Brasil como anorexígeno enquanto a cafeína é amplamente consumida como constituinte regular da dieta. A administração repetida de psicoestimulantes induz sensibilização comportamental que se caracteriza pelo aumento progressivo dos seus efeitos locomotores. Pode ocorrer ainda sensibilização cruzada entre essas substâncias. Investigamos se a administração repetida de cafeína aumenta a locomoção induzida pelo femproporex em ratos adolescentes e adultos. Quarenta e oito ratos adolescentes (dia pós-natal 27 e 32 adultos (dia pós-natal 60 foram distribuídos em dois grupos que receberam injeção intra-peritoneal de 10,0 mg/kg de cafeína (CAF (adolescentes N = 24; adultos N = 16 ou salina (SAL (adolescentes N = 24; adultos N = 16 diariamente durante 10 dias. Três dias após a última injeção, cada grupo CAF ou SAL foi subdividido em dois subgrupos que receberam injeção i.p. de salina (SAL (1 mL/kg ou femproporex (FEM (2,0 mg/kg. Após as injeções, a atividade locomotora foi avaliada automaticamente em intervalos de 5 minutos durante 1 hora. Nossos resultados demonstraram que em ratos adolescentes e adultos o pré-tratamento com CAF aumenta a atividade locomotora induzida pela administração aguda de FEM, sugerindo que a cafeína causa sensibilização aos efeitos locomotores desse derivado anfetamínico.Caffeine and femproporex are psychostimulants drugs widely consumed in Brazil. Behavioral sensitization is defined as an augmentation in the behavioral effect of a psychostimulant upon re-administration. Repeated administration of a psychostimulant produces behavioral sensitization to that drug and cross-sensitization to other drugs. We investigated whether repeated administration of caffeine increases femproporex-induced locomotor activity in adolescent and adult rats. Forty-eight adolescent (postnatal day 27 and 32 adult

Effect of thermal acclimation on locomotor energetics and locomotor performance in a lungless salamander, Desmognathus ochrophaeus.

Science.gov (United States)

Feder, M E

1986-03-01

To determine the effects of thermal acclimation upon locomotor performance and the rate of oxygen consumption (MO2) during activity, small (less than 3 g), lungless salamanders, Desmognathus ochrophaeus Cope, were acclimated to three temperatures (5, 13 and 21 degrees C) and exercised at various controlled speeds within an exercise wheel while their MO2 was measured. MO2 increased with speed at low speeds (less than 14 cm min-1). Although animals could sustain greater speeds, MO2 did not increase further. These small, exclusively skin-breathing salamanders could increase their MO2 9-11 times during exercise and could sustain nearly half of the oxygen flux expected across a similar surface area of the mammalian lung. However, their maximum aerobic speed was remarkably slow (14 cm min-1) and their net cost of transport remarkably large (15-17 ml O2 g-1 km-1). Thermal acclimation affected MO2 during activity, the maximum sustainable speed and locomotor stamina in different ways. During exercise at 13 degrees C, cold-acclimated animals had a significantly greater MO2 than warm-acclimated animals, but did not differ in stamina or the maximum sustainable speed. During exercise at 21 degrees C, cold acclimation did not affect the MO2 significantly, but it decreased the stamina and increased the rate of lactate accumulation. Thus, these results suggest that thermal acclimation of the MO2 is not tightly coupled to thermal acclimation of locomotor performance in salamanders.

Interaction between Sex Hormones and Matricaria Chamomilla Hydroalcholic Extract on Motor Activity Behavior in Gonadectomized Male and Female Mice

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H. Raie

2006-04-01

Full Text Available Introduction & Objective: Locomotor activity is an important physiologic phenomenon that is influenced by several factors. In previous study we showed that the matricaria chamomilla (chamomile hydroalcholic extract acts differently in male and female mice. Therefore in this study, the role of sex hormones and chamomile hydroalcholic extract were investigated on motor activity behavior in absence of sex glands in adult male and female NMRI mice. Materials and Methods: Gonadectomized male and female mice were divided into groups (seven mice in each group including: receiving testosterone (2 mg/kg S.C., estradiol benzoate (0.1 mg/kg S.C., and progesterone (0.5 mg/kg S.C. with and without hydroalcholic extract of chamomile (50 mg/kg i.p. Motor activity monitor system was used to evaluate locomotor activity parameters (fast and slow activity, fast and slow stereotype activity, fast and slow rearing in all groups. Results: 1 Testosterone had no any effect on motor activity parameters, but extract of chamomile with and without testosterone decreased motor activity parameters in male mice. 2 Estradiol benzoate and chamomile hydroalcholic extract in presence and absence of each other increased locomotor activity parameters in female mice. 3 Progesterone also did not change motor activity parameters in presence and absence of chamomile hydroalcholic extract in female mice. 4 Administration of Estradiol benzoate with progestrone in presence and absence of chamomile hydroalcholic extract did not alter motor activity parameters in female mice. Conclusion: It seems both of the chamomile hydroalcholic extract and estradiol enhance motor activity and probably act through same system and potentiate the effect of each other. Also it seems there are interaction between estradiol and progesterone and also between chamomile extract and progesterone. Testosterone probably did not have any interaction with chamomile extract in locomotor activity.

Hesperidin effects on behavior and locomotor activity of diabetic ...

African Journals Online (AJOL)

African Journal of Biotechnology ... Today, there are sufficient validated scientific data that support the existence of relations between diabetes and certain ... disorders, such as behavioral disorders, anxiety, cognitive decline and depression.

Selective brain lesions reduce morphine- and radiation-induced locomotor hyperactivity of the C57BL/6J mouse

International Nuclear Information System (INIS)

Mickley, G.A.; Stevens, K.E.; White, G.A.; Gibbs, G.L.

1984-01-01

The apparent resemblance between the stereotypic locomotor hyperactivity observed after either an injection of morphine or irradiation of the C57BL/6J mouse has suggested the possibility of similar biochemical and neuroanatomical substrates of these behaviors. In this study the authors made selective brain lesions in an attempt to reverse the locomotor response observed after morphine (30 mg/kg) or radiation (1500 rads /sup 60/Co) treatments. Lesions impinging on both the dorso-medial caudate and lateral septal nuclei caused a significant decrease in morphine-induced and radiogenic locomotion. Lesions of the individual brain areas did not significantly alter the opiate locomotor response. This reduction in locomotion could not be attributed to a generalized post-surgical lethargy since other brain lesions of similar size did not significantly suppress these behaviors. These data suggest the possibility of some common central nervous system mechanisms which may support the stereotypic locomotor hyperactivity observed in the C57BL/6J mouse after either morphine or radiation treatment

Hesperidin effects on behavior and locomotor activity of diabetic ...

African Journals Online (AJOL)

Tuoyo Aghomotsegin

2016-11-09

Nov 9, 2016 ... causing behavioral disorders, depression and cognitive dysfunction .... to control which was analysed using Student's t-test, at P<0.05. RESULTS .... music is used as a therapy that modulates a combined predator and noise ...

Shared human-chimpanzee pattern of perinatal femoral shaft morphology and its implications for the evolution of hominin locomotor adaptations.

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Naoki Morimoto

Full Text Available Acquisition of bipedality is a hallmark of human evolution. How bipedality evolved from great ape-like locomotor behaviors, however, is still highly debated. This is mainly because it is difficult to infer locomotor function, and even more so locomotor kinematics, from fossil hominin long bones. Structure-function relationships are complex, as long bone morphology reflects phyletic history, developmental programs, and loading history during an individual's lifetime. Here we discriminate between these factors by investigating the morphology of long bones in fetal and neonate great apes and humans, before the onset of locomotion.Comparative morphometric analysis of the femoral diaphysis indicates that its morphology reflects phyletic relationships between hominoid taxa to a greater extent than taxon-specific locomotor adaptations. Diaphyseal morphology in humans and chimpanzees exhibits several shared-derived features, despite substantial differences in locomotor adaptations. Orangutan and gorilla morphologies are largely similar, and likely represent the primitive hominoid state.These findings are compatible with two possible evolutionary scenarios. Diaphyseal morphology may reflect retained adaptive traits of ancestral taxa, hence human-chimpanzee shared-derived features may be indicative of the locomotor behavior of our last common ancestor. Alternatively, diaphyseal morphology might reflect evolution by genetic drift (neutral evolution rather than selection, and might thus be more informative about phyletic relationships between taxa than about locomotor adaptations. Both scenarios are consistent with the hypothesis that knuckle-walking in chimpanzees and gorillas resulted from convergent evolution, and that the evolution of human bipedality is unrelated to extant great ape locomotor specializations.

Effects of pinealectomy on the neuroendocrine reproductive system and locomotor activity in male European sea bass, Dicentrarchus labrax.

Science.gov (United States)

Cowan, Mairi; Paullada-Salmerón, José A; López-Olmeda, José Fernando; Sánchez-Vázquez, Francisco Javier; Muñoz-Cueto, José A

2017-05-01

The seasonally changing photoperiod controls the timing of reproduction in most fish species, however, the transduction of this photoperiodic information to the reproductive axis is still unclear. This study explored the potential role of two candidate neuropeptide systems, gonadotropin-inhibitory hormone (Gnih) and kisspeptin, as mediators between the pineal organ (a principle transducer of photoperiodic information) and reproductive axis in male European sea bass, Dicentrarchus labrax. Two seven-day experiments of pinealectomy (Px) were performed, in March (end of reproductive season) and August (resting season). Effects of Px and season on the brain expression of gnih (sbgnih) and its receptor (sbgnihr), kisspeptins (kiss1, kiss2) and their receptors (kissr2, kissr3) and gonadotropin-releasing hormone (gnrh1, gnrh2, gnrh3) and the main brain receptor (gnrhr-II-2b) genes, plasma melatonin levels and locomotor activity rhythms were examined. Results showed that Px reduced night-time plasma melatonin levels. Gene expression analyses demonstrated a sensitivity of the Gnih system to Px in March, with a reduction in sbgnih in the mid-hindbrain, a region with bilateral connections to the pineal organ. In August, kiss2 levels increased in Px animals but not in controls. Significant differences in expression were observed for diencephalic sbgnih, sbgnihr, kissr3 and tegmental gnrh2 between seasons. Recordings of locomotor activity following surgery revealed a change from light-synchronised to free-running rhythmic behavior. Altogether, the Gnih and Kiss2 sensitivity to Px and seasonal differences observed for Gnih and its receptor, Gnrh2, and the receptor for Kiss2 (Kissr3), suggested they could be mediators involved in the relay between environment and seasonal reproduction. Copyright © 2017 Elsevier Inc. All rights reserved.

Spontaneous locomotor activity correlates with the degranulation of mast cells in the meninges rather than in the thalamus: disruptive effect of cocaine.

Science.gov (United States)

Larson, Alice A; Thomas, Mark J; McElhose, Alex; Kovács, Katalin J

2011-06-13

Mast cells are located in the central nervous system (CNS) of many mammals and stress induces their degranulation. We postulated that mast cells are associated with wakefulness and stimulatory tone in the CNS, as reflected by spontaneous motor activity. Because stress also precipitates drug-seeking behavior in cocaine addicts, we also postulated that cocaine manifests its effects through this relationship. We investigated the influence of single and repeated injections of cocaine on circulating corticosterone, motor activity and degranulation of mast cells in both the thalamus and meninges of mice. Mice were subjected to 5 consecutive days of cocaine or saline followed by a single injection of cocaine or saline 11 days later. Spontaneous locomotor activity was measure for 1h after the final injection before death. Neither a single injection nor prior treatment with cocaine increased motor activity compared to saline-injected controls, however, repeated administration of cocaine induced a significant sensitization to its behavioral effect when delivered 11 days later. In mice that received only saline, motor activity correlated positively with mast cell degranulation in the meninges but not in the thalamus. Cocaine, regardless of the treatment schedule, disrupted this correlation. The concentration of corticosterone did not differ amongst groups and did not correlate with either behavior or mast cell parameters in any group. The correlation between behavioral activity and the mast cell degranulation in the meninges suggests that these parameters are linked. The disruptive effect of cocaine on this relationship indicates a role downstream from mast cells in the regulation of motor activity. Copyright © 2011 Elsevier B.V. All rights reserved.

Endogenous opiates mediate radiogenic behavioral change

International Nuclear Information System (INIS)

Mickley, G.A.; Stevens, K.E.; White, G.A.; Gibbs, G.L.

1983-01-01

Exposure of C57BL/6J mice to ionizing radiation caused stereotypical locomotor hyperactivity similar to that produced by morphine. Naloxone administration prevented this radiation-induced behavioral activation. These results support the hypothesis that endorphins are involved in some aspects of radiogenic behavioral change

The delta-opioid receptor agonist SNC80 [(+)-4-[alpha(R)-alpha-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-(3-methoxybenzyl)-N,N-diethylbenzamide] synergistically enhances the locomotor-activating effects of some psychomotor stimulants, but not direct dopamine agonists, in rats.

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Jutkiewicz, Emily M; Baladi, Michelle G; Folk, John E; Rice, Kenner C; Woods, James H

2008-02-01

The nonpeptidic delta-opioid agonist SNC80 [(+)-4-[alpha(R)-alpha-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-(3-methoxybenzyl)-N,N-diethylbenzamide] produces many stimulant-like behavioral effects in rodents and monkeys, such as locomotor stimulation, generalization to cocaine in discrimination procedures, and antiparkinsonian effects. Tolerance to the locomotor-stimulating effects of SNC80 develops after a single administration of SNC80 in rats; it is not known whether cross-tolerance develops to the effects of other stimulant compounds. In the initial studies to determine whether SNC80 produced cross-tolerance to other stimulant compounds, it was discovered that amphetamine-stimulated locomotor activity was greatly enhanced in SNC80-pretreated rats. This study evaluated acute cross-tolerance between delta-opioid agonists and other locomotor-stimulating drugs. Locomotor activity was measured in male Sprague-Dawley rats implanted with radiotransmitters, and activity levels were recorded in the home cage environment. Three-hour SNC80 pretreatment produced tolerance to further delta-opioid receptor stimulation but also augmented greatly amphetamine-stimulated locomotor activity in a dose-dependent manner. Pretreatments with other delta-opioid agonists, (+)BW373U86 [(+)-4-[alpha(R)-alpha-[(2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl]-3-hydroxybenzyl]-N,N-diethylbenzamide] and oxymorphindole (17-methyl-6,7-dehydro-4,5-epoxy-3,14-dihydroxy-6,7,2',3'-indolomorphinan), also modified amphetamine-induced activity levels. SNC80 pretreatment enhanced the stimulatory effects of the dopamine/norepinephrine transporter ligands cocaine and nomifensine (1,2,3,4-tetrahydro-2-methyl-4-phenyl-8-isoquinolinanmine maleate salt), but not the direct dopamine receptor agonists SKF81297 [R-(+)-6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide] and quinpirole [trans-(-)-(4alphaR)-4,4a, 5,6,7,8,8a,9-octahydro-5-propyl-1H-pyrazolo[3,4-g] quinoline

Early-life risperidone enhances locomotor responses to amphetamine during adulthood.

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Lee Stubbeman, Bobbie; Brown, Clifford J; Yates, Justin R; Bardgett, Mark E

2017-10-05

Antipsychotic drug prescriptions for pediatric populations have increased over the past 20 years, particularly the use of atypical antipsychotic drugs such as risperidone. Most antipsychotic drugs target forebrain dopamine systems, and early-life antipsychotic drug exposure could conceivably reset forebrain neurotransmitter function in a permanent manner that persists into adulthood. This study determined whether chronic risperidone administration during development modified locomotor responses to the dopamine/norepinephrine agonist, D-amphetamine, in adult rats. Thirty-five male Long-Evans rats received an injection of one of four doses of risperidone (vehicle, .3, 1.0, 3.0mg/kg) each day from postnatal day 14 through 42. Locomotor activity was measured for 1h on postnatal days 46 and 47, and then for 24h once a week over the next two weeks. Beginning on postnatal day 75, rats received one of four doses of amphetamine (saline, .3, 1.0, 3.0mg/kg) once a week for four weeks. Locomotor activity was measured for 27h after amphetamine injection. Rats administered risperidone early in life demonstrated increased activity during the 1 and 24h test sessions conducted prior to postnatal day 75. Taking into account baseline group differences, these same rats exhibited significantly more locomotor activity in response to the moderate dose of amphetamine relative to controls. These results suggest that early-life treatment with atypical antipsychotic drugs, like risperidone, permanently alters forebrain catecholamine function and increases sensitivity to drugs that target such function. Copyright © 2017 Elsevier B.V. All rights reserved.

Transcriptome analysis of the brain of the silkworm Bombyx mori infected with Bombyx mori nucleopolyhedrovirus: A new insight into the molecular mechanism of enhanced locomotor activity induced by viral infection.

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Wang, Guobao; Zhang, Jianjia; Shen, Yunwang; Zheng, Qin; Feng, Min; Xiang, Xingwei; Wu, Xiaofeng

2015-06-01

Baculoviruses have been known to induce hyperactive behavior in their lepidopteran hosts for over a century. As a typical lepidopteran insect, the silkworm Bombyx mori displays enhanced locomotor activity (ELA) following infection with B. mori nucleopolyhedrovirus (BmNPV). Some investigations have focused on the molecular mechanisms underlying this abnormal hyperactive wandering behavior due to the virus; however, there are currently no reports about B. mori. Based on previous studies that have revealed that behavior is controlled by the central nervous system, the transcriptome profiles of the brains of BmNPV-infected and non-infected silkworm larvae were analyzed with the RNA-Seq technique to reveal the changes in the BmNPV-infected brain on the transcriptional level and to provide new clues regarding the molecular mechanisms that underlies BmNPV-induced ELA. Compared with the controls, a total of 742 differentially expressed genes (DEGs), including 218 up-regulated and 524 down-regulated candidates, were identified, of which 499, 117 and 144 DEGs could be classified into GO categories, KEGG pathways and COG annotations by GO, KEGG and COG analyses, respectively. We focused our attention on the DEGs that are involved in circadian rhythms, synaptic transmission and the serotonin receptor signaling pathway of B. mori. Our analyses suggested that these genes were related to the locomotor activity of B. mori via their essential roles in the regulations of a variety of behaviors and the down-regulation of their expressions following BmNPV infection. These results provide new insight into the molecular mechanisms of BmNPV-induced ELA. Copyright © 2015 Elsevier Inc. All rights reserved.

Mice Lacking EGR1 Have Impaired Clock Gene (BMAL1) Oscillation, Locomotor Activity, and Body Temperature.

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Riedel, Casper Schwartz; Georg, Birgitte; Jørgensen, Henrik L; Hannibal, Jens; Fahrenkrug, Jan

2018-01-01

Early growth response transcription factor 1 (EGR1) is expressed in the suprachiasmatic nucleus (SCN) after light stimulation. We used EGR1-deficient mice to address the role of EGR1 in the clock function and light-induced resetting of the clock. The diurnal rhythms of expression of the clock genes BMAL1 and PER1 in the SCN were evaluated by semi-quantitative in situ hybridization. We found no difference in the expression of PER1 mRNA between wildtype and EGR1-deficient mice; however, the daily rhythm of BMAL1 mRNA was completely abolished in the EGR1-deficient mice. In addition, we evaluated the circadian running wheel activity, telemetric locomotor activity, and core body temperature of the mice. Loss of EGR1 neither altered light-induced phase shifts at subjective night nor affected negative masking. Overall, circadian light entrainment was found in EGR1-deficient mice but they displayed a reduced locomotor activity and an altered temperature regulation compared to wild type mice. When placed in running wheels, a subpopulation of EGR1-deficient mice displayed a more disrupted activity rhythm with no measurable endogenous period length (tau). In conclusion, the present study provides the first evidence that the circadian clock in the SCN is disturbed in mice deficient of EGR1.

Interpreting locomotor biomechanics from the morphology of human footprints.

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Hatala, Kevin G; Wunderlich, Roshna E; Dingwall, Heather L; Richmond, Brian G

2016-01-01

Fossil hominin footprints offer unique direct windows to the locomotor behaviors of our ancestors. These data could allow a clearer understanding of the evolution of human locomotion by circumventing issues associated with indirect interpretations of habitual locomotor patterns from fossil skeletal material. However, before we can use fossil hominin footprints to understand better the evolution of human locomotion, we must first develop an understanding of how locomotor biomechanics are preserved in, and can be inferred from, footprint morphologies. In this experimental study, 41 habitually barefoot modern humans created footprints under controlled conditions in which variables related to locomotor biomechanics could be quantified. Measurements of regional topography (depth) were taken from 3D models of those footprints, and principal components analysis was used to identify orthogonal axes that described the largest proportions of topographic variance within the human experimental sample. Linear mixed effects models were used to quantify the influences of biomechanical variables on the first five principal axes of footprint topographic variation, thus providing new information on the biomechanical variables most evidently expressed in the morphology of human footprints. The footprint's overall depth was considered as a confounding variable, since biomechanics may be linked to the extent to which a substrate deforms. Three of five axes showed statistically significant relationships with variables related to both locomotor biomechanics and substrate displacement; one axis was influenced only by biomechanics and another only by the overall depth of the footprint. Principal axes of footprint morphological variation were significantly related to gait type (walking or running), kinematics of the hip and ankle joints and the distribution of pressure beneath the foot. These results provide the first quantitative framework for developing hypotheses regarding the

Individual differences in ethanol locomotor sensitization are associated with dopamine D1 receptor intra-cellular signaling of DARPP-32 in the nucleus accumbens.

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Karina Possa Abrahao

Full Text Available In mice there are clear individual differences in the development of behavioral sensitization to ethanol, a progressive potentiation of its psychomotor stimulant effect. Variability in the behavioral responses to ethanol has been associated with alcohol preference. Here we investigated if the functional hyperresponsiveness of D1 receptors observed in ethanol sensitized mice leads to an increased activation of DARPP-32, a central regulatory protein in medium spiny neurons, in the nucleus accumbens - a brain region known to play a role in drug reinforcement. Swiss Webster mice received ethanol (2.2 g/kg/day or saline i.p. administrations for 21 days and were weekly evaluated regarding their locomotor activity. From those treated with ethanol, the 33% with the highest levels of locomotor activity were classified as "sensitized" and the 33% with the lowest levels as "non-sensitized". The latter presented similar locomotor levels to those of saline-treated mice. Different subgroups of mice received intra-accumbens administrations of saline and, 48 h later, SKF-38393, D1 receptor agonist 0.1 or 1 µg/side. Indeed, sensitized mice presented functional hyperresponsiveness of D1 receptors in the accumbens. Two weeks following the ethanol treatment, other subgroups received systemic saline or SKF 10 mg/kg, 20 min before the euthanasia. The nucleus accumbens were dissected for the Western Blot analyses of total DARPP-32 and phospho-Thr34-DARPP-32 expression. D1 receptor activation induced higher phospho-Thr34-DARPP-32 expression in sensitized mice than in non-sensitized or saline. The functionally hyperresponsiveness of D1 receptors in the nucleus accumbens is associated with an increased phospho-Thr34-DARPP-32 expression after D1 receptor activation. These data suggest that an enduring increase in the sensitivity of the dopamine D1 receptor intracellular pathway sensitivity represents a neurobiological correlate associated with the development of

SEE locomotor behavior test discriminates C57BL/6J and DBA/2J mouse inbred strains across laboratories and protocol conditions.

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Kafkafi, Neri; Lipkind, Dina; Benjamini, Yoav; Mayo, Cheryl L; Elmer, Gregory I; Golani, Ilan

2003-06-01

Conventional tests of behavioral phenotyping frequently have difficulties differentiating certain genotypes and replicating these differences across laboratories and protocol conditions. This study explores the hypothesis that automated tests can be designed to quantify ethologically relevant behavior patterns that more readily characterize heritable and replicable phenotypes. It used SEE (Strategy for the Exploration of Exploration) to phenotype the locomotor behavior of the C57BL/6 and DBA/2 mouse inbred strains across 3 laboratories. The 2 genotypes differed in 15 different measures of behavior, none of which had a significant genotype-laboratory interaction. Within the same laboratory, most of these differences were replicated in additional experiments despite the test photoperiod phase being changed and saline being injected. Results suggest that well-designed tests may considerably enhance replicability across laboratories.

Oxotremorine treatment reduces repetitive behaviors in BTBR T+ tf/J mice

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Dionisio A. Amodeo

2014-08-01

Full Text Available Repetitive behaviors with restricted interests is one of the core criteria for the diagnosis of autism spectrum disorder (ASD. Current pharmacotherapies that target the dopaminergic or serotonergic systems have limited effectiveness in treating repetitive behaviors. Previous research has demonstrated that administration of muscarinic cholinergic receptor (mAChR antagonists can exacerbate motor stereotypies while mAChR agonists reduce stereotypies. The present study determined whether the mAChR agonist, oxotremorine affected repetitive behaviors in the BTBR T+ tf/J (BTBR mouse model of autism. To test the effects of oxotremorine on repetitive behaviors, marble burying and grooming behavior were measured in BTBR mice and compared to that in C57BL/6J (B6 mice. The effects of oxotremorine on locomotor activity was also measured. Thirty minutes before each test, mice received an intraperitoneal injection of saline, 0.001 mg or 0.01 mg of oxotremorine methiodide. Saline- treated BTBR mice exhibited increased marble burying and self-grooming behavior compared to that of saline-treated B6 mice. Oxotremorine significantly reduced marble burying and self-grooming behavior in BTBR mice, but had no significant effect in B6 mice. In addition, oxotremorine did not affect locomotor activity in BTBR mice, but significantly reduced locomotor activity in B6 mice at the 0.01 mg dose. These findings demonstrate that activation of mAChRs reduces repetitive behavior in the BTBR mouse and suggest that treatment with a mAChR agonist may be effective in reducing repetitive behaviors in ASD.

Cognitive Performance and Locomotor Adaptation in Persons With Anterior Cruciate Ligament Reconstruction.

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Stone, Amanda E; Roper, Jaimie A; Herman, Daniel C; Hass, Chris J

2018-05-01

Persons with anterior cruciate ligament reconstruction (ACLR) show deficits in gait and neuromuscular control following rehabilitation. This altered behavior extends to locomotor adaptation and learning, however the contributing factors to this observed behavior have yet to be investigated. The purpose of this study was to assess differences in locomotor adaptation and learning between ACLR and controls, and identify underlying contributors to motor adaptation in these individuals. Twenty ACLR individuals and 20 healthy controls (CON) agreed to participate in this study. Participants performed four cognitive and dexterity tasks (local version of Trail Making Test, reaction time test, electronic pursuit rotor test, and the Purdue pegboard). Three-dimensional kinematics were also collected while participants walked on a split-belt treadmill. ACLR individuals completed the local versions of Trails A and Trails B significantly faster than CON. During split-belt walking, ACLR individuals demonstrated smaller step length asymmetry during EARLY and LATE adaptation, smaller double support asymmetry during MID adaptation, and larger stance time asymmetry during DE-ADAPT compared with CON. ACLR individuals performed better during tasks that required visual attention and task switching and were less perturbed during split-belt walking compared to controls. Persons with ACLR may use different strategies than controls, cognitive or otherwise, to adapt locomotor patterns.

Descending propriospinal neurons mediate restoration of locomotor function following spinal cord injury

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Benthall, Katelyn N.; Hough, Ryan A.

2016-01-01

Following spinal cord injury (SCI) in the lamprey, there is virtually complete recovery of locomotion within a few weeks, but interestingly, axonal regeneration of reticulospinal (RS) neurons is mostly limited to short distances caudal to the injury site. To explain this situation, we hypothesize that descending propriospinal (PS) neurons relay descending drive from RS neurons to indirectly activate spinal central pattern generators (CPGs). In the present study, the contributions of PS neurons to locomotor recovery were tested in the lamprey following SCI. First, long RS neuron projections were interrupted by staggered spinal hemitransections on the right side at 10% body length (BL; normalized from the tip of the oral hood) and on the left side at 30% BL. For acute recovery conditions (≤1 wk) and before axonal regeneration, swimming muscle burst activity was relatively normal, but with some deficits in coordination. Second, lampreys received two spaced complete spinal transections, one at 10% BL and one at 30% BL, to interrupt long-axon RS neuron projections. At short recovery times (3–5 wk), RS and PS neurons will have regenerated their axons for short distances and potentially established a polysynaptic descending command pathway. At these short recovery times, swimming muscle burst activity had only minor coordination deficits. A computer model that incorporated either of the two spinal lesions could mimic many aspects of the experimental data. In conclusion, descending PS neurons are a viable mechanism for indirect activation of spinal locomotor CPGs, although there can be coordination deficits of locomotor activity. NEW & NOTEWORTHY In the lamprey following spinal lesion-mediated interruption of long axonal projections of reticulospinal (RS) neurons, sensory stimulation still elicited relatively normal locomotor muscle burst activity, but with some coordination deficits. Computer models incorporating the spinal lesions could mimic many aspects of the

Descending propriospinal neurons mediate restoration of locomotor function following spinal cord injury.

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Benthall, Katelyn N; Hough, Ryan A; McClellan, Andrew D

2017-01-01

Following spinal cord injury (SCI) in the lamprey, there is virtually complete recovery of locomotion within a few weeks, but interestingly, axonal regeneration of reticulospinal (RS) neurons is mostly limited to short distances caudal to the injury site. To explain this situation, we hypothesize that descending propriospinal (PS) neurons relay descending drive from RS neurons to indirectly activate spinal central pattern generators (CPGs). In the present study, the contributions of PS neurons to locomotor recovery were tested in the lamprey following SCI. First, long RS neuron projections were interrupted by staggered spinal hemitransections on the right side at 10% body length (BL; normalized from the tip of the oral hood) and on the left side at 30% BL. For acute recovery conditions (≤1 wk) and before axonal regeneration, swimming muscle burst activity was relatively normal, but with some deficits in coordination. Second, lampreys received two spaced complete spinal transections, one at 10% BL and one at 30% BL, to interrupt long-axon RS neuron projections. At short recovery times (3-5 wk), RS and PS neurons will have regenerated their axons for short distances and potentially established a polysynaptic descending command pathway. At these short recovery times, swimming muscle burst activity had only minor coordination deficits. A computer model that incorporated either of the two spinal lesions could mimic many aspects of the experimental data. In conclusion, descending PS neurons are a viable mechanism for indirect activation of spinal locomotor CPGs, although there can be coordination deficits of locomotor activity. In the lamprey following spinal lesion-mediated interruption of long axonal projections of reticulospinal (RS) neurons, sensory stimulation still elicited relatively normal locomotor muscle burst activity, but with some coordination deficits. Computer models incorporating the spinal lesions could mimic many aspects of the experimental results

Visual and kinesthetic locomotor imagery training integrated with auditory step rhythm for walking performance of patients with chronic stroke.

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Kim, Jin-Seop; Oh, Duck-Won; Kim, Suhn-Yeop; Choi, Jong-Duk

2011-02-01

To compare the effect of visual and kinesthetic locomotor imagery training on walking performance and to determine the clinical feasibility of incorporating auditory step rhythm into the training. Randomized crossover trial. Laboratory of a Department of Physical Therapy. Fifteen subjects with post-stroke hemiparesis. Four locomotor imagery trainings on walking performance: visual locomotor imagery training, kinesthetic locomotor imagery training, visual locomotor imagery training with auditory step rhythm and kinesthetic locomotor imagery training with auditory step rhythm. The timed up-and-go test and electromyographic and kinematic analyses of the affected lower limb during one gait cycle. After the interventions, significant differences were found in the timed up-and-go test results between the visual locomotor imagery training (25.69 ± 16.16 to 23.97 ± 14.30) and the kinesthetic locomotor imagery training with auditory step rhythm (22.68 ± 12.35 to 15.77 ± 8.58) (P kinesthetic locomotor imagery training exhibited significantly increased activation in a greater number of muscles and increased angular displacement of the knee and ankle joints compared with the visual locomotor imagery training, and these effects were more prominent when auditory step rhythm was integrated into each form of locomotor imagery training. The activation of the hamstring during the swing phase and the gastrocnemius during the stance phase, as well as kinematic data of the knee joint, were significantly different for posttest values between the visual locomotor imagery training and the kinesthetic locomotor imagery training with auditory step rhythm (P kinesthetic locomotor imagery training than in the visual locomotor imagery training. The auditory step rhythm together with the locomotor imagery training produces a greater positive effect in improving the walking performance of patients with post-stroke hemiparesis.

Assessment of locomotion behavior in adult Zebrafish after acute exposure to different pharmacological reference compounds

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Pankaj Gupta

2014-01-01

Full Text Available Objectives: The objective of the present study was to assess locomotor behavior of adult zebrafish after acute exposure to different pharmacological reference compounds. Materials and Methods: Adult zebrafish of 4-5-months-old were exposed to different concentrations of known reference compounds for 15 min. The test was conducted separately for each drug concentration as well as control. Locomotor activity parameters viz. distance travelled, speed, total mobile time, and total immobile time were recorded for each animal during the exposure period. Results: Out of 11 compounds tested, nine compounds showed decrease in locomotor behavior with significant changes in distance travelled, speed, total mobile time, and total immobile time. Caffeine exhibited biphasic response in locomotion behavior, while scopolamine failed to induce any significant changes. Conclusion: In view of the above findings, these results suggested that exposure of adult zebrafish with different known compounds produce the expected changes in the locomotion behavior; therefore, adult zebrafish can be used an alternative approach for the assessment of new chemical entities for their effect on locomotor behavior.

A simple behavioral test for locomotor function after brain injury in mice.

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Tabuse, Masanao; Yaguchi, Masae; Ohta, Shigeki; Kawase, Takeshi; Toda, Masahiro

2010-11-01

To establish a simple and reliable test for assessing locomotor function in mice with brain injury, we developed a new method, the rotarod slip test, in which the number of slips of the paralytic hind limb from a rotarod is counted. Brain injuries of different severity were created in adult C57BL/6 mice, by inflicting 1-point, 2-point and 4-point cryo-injuries. These mice were subjected to the rotarod slip test, the accelerating rotarod test and the elevated body swing test (EBST). Histological analyses were performed to assess the severity of the brain damage. Significant and consistent correlations between test scores and severity were observed for the rotarod slip test and the EBST. Only the rotarod slip test detected the mild hindlimb paresis in the acute and sub-acute phase after injury. Our results suggest that the rotarod slip test is the most sensitive and reliable method for assessing locomotor function after brain damage in mice. Copyright © 2010 Elsevier Ltd. All rights reserved.

Onset of behavioral effects in mice exposed to 10 Gy Co-60 radiation

International Nuclear Information System (INIS)

Maier, D.M.; Landauer, M.R.

1990-01-01

The effects of 10 Gray (Gy) Co-60 radiation on social behavior, locomotor activity, and body weight were assessed in individually housed male Swiss-Webster mice. In experiment 1, aggressive behavior was evaluated prior to irradiation and for 7 d postirradiation by placing an untreated intruder in the irradiated or sham-irradiated resident's home cage for 5 min. Offensive aggressive behavior was not affected significantly by radiation until day 7 postirradiation, when attack latency increased, the frequency and duration of fighting decreased, and the frequency of bites, lunges, and chases decreased. Untreated intruder mice paired with irradiated resident mice showed a decrease in the duration of defensive upright postures and a decrease in the frequency of defensive upright postures, squeaks, and escapes on day 7 postirradiation. In experiment 2, locomotor activity and body weight were monitored for 7 d postirradiation. Body weight was decreased in irradiated mice beginning 4 d postirradiation. Locomotor activity was suppressed in irradiated animals 90 min after irradiation and remained depressed throughout the 7-d testing period. 25 refs

The relationship between hippocampal EEG theta activity and locomotor behaviour in freely moving rats: effects of vigabatrin.

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Bouwman, B M; van Lier, H; Nitert, H E J; Drinkenburg, W H I M; Coenen, A M L; van Rijn, C M

2005-01-30

The relationship between hippocampal electroencephalogram (EEG) theta activity and locomotor speed in both spontaneous and forced walking conditions was studied in rats after vigabatrin injection (500 mg/kg i.p.). Vigabatrin increased the percentage of time that rats spent being immobile. During spontaneous walking in the open field, the speed of locomotion was increased by vigabatrin, while theta peak frequency was decreased. Vigabatrin also reduced the theta peak frequency during forced (speed controlled) walking. There was only a weak positive correlation (r=0.22) between theta peak frequency and locomotor speed for the saline condition. Furthermore, vigabatrin abolishes the weak relationship between speed of locomotion and theta peak frequency. Vigabatrin and saline did not differ in the slope of the regression line, but showed different offset points at the theta peak frequency axis. Thus, other factors than speed of locomotion seem to be involved in determination of the theta peak frequency.

Rhythmic 24 h variation of core body temperature and locomotor activity in a subterranean rodent (Ctenomys aff. knighti, the tuco-tuco.

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Patricia Tachinardi

Full Text Available The tuco-tuco Ctenomys aff. knighti is a subterranean rodent which inhabits a semi-arid area in Northwestern Argentina. Although they live in underground burrows where environmental cycles are attenuated, they display robust, 24 h locomotor activity rhythms that are synchronized by light/dark cycles, both in laboratory and field conditions. The underground environment also poses energetic challenges (e.g. high-energy demands of digging, hypoxia, high humidity, low food availability that have motivated thermoregulation studies in several subterranean rodent species. By using chronobiological protocols, the present work aims to contribute towards these studies by exploring day-night variations of thermoregulatory functions in tuco-tucos, starting with body temperature and its temporal relationship to locomotor activity. Animals showed daily, 24 h body temperature rhythms that persisted even in constant darkness and temperature, synchronizing to a daily light/dark cycle, with highest values occurring during darkness hours. The range of oscillation of body temperature was slightly lower than those reported for similar-sized and dark-active rodents. Most rhythmic parameters, such as period and phase, did not change upon removal of the running wheel. Body temperature and locomotor activity rhythms were robustly associated in time. The former persisted even after removal of the acute effects of intense activity on body temperature by a statistical method. Finally, regression gradients between body temperature and activity were higher in the beginning of the night, suggesting day-night variation in thermal conductance and heat production. Consideration of these day-night variations in thermoregulatory processes is beneficial for further studies on thermoregulation and energetics of subterranean rodents.

Dual spinal lesion paradigm in the cat: evolution of the kinematic locomotor pattern.

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Barrière, Grégory; Frigon, Alain; Leblond, Hugues; Provencher, Janyne; Rossignol, Serge

2010-08-01

The recovery of voluntary quadrupedal locomotion after an incomplete spinal cord injury can involve different levels of the CNS, including the spinal locomotor circuitry. The latter conclusion was reached using a dual spinal lesion paradigm in which a low thoracic partial spinal lesion is followed, several weeks later, by a complete spinal transection (i.e., spinalization). In this dual spinal lesion paradigm, cats can express hindlimb walking 1 day after spinalization, a process that normally takes several weeks, suggesting that the locomotor circuitry within the lumbosacral spinal cord had been modified after the partial lesion. Here we detail the evolution of the kinematic locomotor pattern throughout the dual spinal lesion paradigm in five cats to gain further insight into putative neurophysiological mechanisms involved in locomotor recovery after a partial spinal lesion. All cats recovered voluntary quadrupedal locomotion with treadmill training (3-5 days/wk) over several weeks. After the partial lesion, the locomotor pattern was characterized by several left/right asymmetries in various kinematic parameters, such as homolateral and homologous interlimb coupling, cycle duration, and swing/stance durations. When no further locomotor improvement was observed, cats were spinalized. After spinalization, the hindlimb locomotor pattern rapidly reappeared, but left/right asymmetries in swing/stance durations observed after the partial lesion could disappear or reverse. It is concluded that, after a partial spinal lesion, the hindlimb locomotor pattern was actively maintained by new dynamic interactions between spinal and supraspinal levels but also by intrinsic changes within the spinal cord.

Drosophila Clock Is Required in Brain Pacemaker Neurons to Prevent Premature Locomotor Aging Independently of Its Circadian Function.

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Alexandra Vaccaro

2017-01-01

Full Text Available Circadian clocks control many self-sustained rhythms in physiology and behavior with approximately 24-hour periodicity. In many organisms, oxidative stress and aging negatively impact the circadian system and sleep. Conversely, loss of the clock decreases resistance to oxidative stress, and may reduce lifespan and speed up brain aging and neurodegeneration. Here we examined the effects of clock disruptions on locomotor aging and longevity in Drosophila. We found that lifespan was similarly reduced in three arrhythmic mutants (ClkAR, cyc0 and tim0 and in wild-type flies under constant light, which stops the clock. In contrast, ClkAR mutants showed significantly faster age-related locomotor deficits (as monitored by startle-induced climbing than cyc0 and tim0, or than control flies under constant light. Reactive oxygen species accumulated more with age in ClkAR mutant brains, but this did not appear to contribute to the accelerated locomotor decline of the mutant. Clk, but not Cyc, inactivation by RNA interference in the pigment-dispersing factor (PDF-expressing central pacemaker neurons led to similar loss of climbing performance as ClkAR. Conversely, restoring Clk function in these cells was sufficient to rescue the ClkAR locomotor phenotype, independently of behavioral rhythmicity. Accelerated locomotor decline of the ClkAR mutant required expression of the PDF receptor and correlated to an apparent loss of dopaminergic neurons in the posterior protocerebral lateral 1 (PPL1 clusters. This neuronal loss was rescued when the ClkAR mutation was placed in an apoptosis-deficient background. Impairing dopamine synthesis in a single pair of PPL1 neurons that innervate the mushroom bodies accelerated locomotor decline in otherwise wild-type flies. Our results therefore reveal a novel circadian-independent requirement for Clk in brain circadian neurons to maintain a subset of dopaminergic cells and avoid premature locomotor aging in Drosophila.

Developmental Changes in Dopamine Neurotransmission in Adolescence: Behavioral Implications and Issues in Assessment

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Wahlstrom, Dustin; Collins, Paul; White, Tonya; Luciana, Monica

2010-01-01

Adolescence is characterized by increased risk-taking, novelty-seeking, and locomotor activity, all of which suggest a heightened appetitive drive. The neurotransmitter dopamine is typically associated with behavioral activation and heightened forms of appetitive behavior in mammalian species, and this pattern of activation has been described in…

Dynamic locomotor capabilities revealed by early dinosaur trackmakers from southern Africa.

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Jeffrey A Wilson

Full Text Available BACKGROUND: A new investigation of the sedimentology and ichnology of the Early Jurassic Moyeni tracksite in Lesotho, southern Africa has yielded new insights into the behavior and locomotor dynamics of early dinosaurs. METHODOLOGY/PRINCIPAL FINDINGS: The tracksite is an ancient point bar preserving a heterogeneous substrate of varied consistency and inclination that includes a ripple-marked riverbed, a bar slope, and a stable algal-matted bar top surface. Several basal ornithischian dinosaurs and a single theropod dinosaur crossed its surface within days or perhaps weeks of one another, but responded to substrate heterogeneity differently. Whereas the theropod trackmaker accommodated sloping and slippery surfaces by gripping the substrate with its pedal claws, the basal ornithischian trackmakers adjusted to the terrain by changing between quadrupedal and bipedal stance, wide and narrow gauge limb support (abduction range = 31 degrees , and plantigrade and digitigrade foot posture. CONCLUSIONS/SIGNIFICANCE: The locomotor adjustments coincide with changes in substrate consistency along the trackway and appear to reflect 'real time' responses to a complex terrain. It is proposed that these responses foreshadow important locomotor transformations characterizing the later evolution of the two main dinosaur lineages. Ornithischians, which shifted from bipedal to quadrupedal posture at least three times in their evolutionary history, are shown to have been capable of adopting both postures early in their evolutionary history. The substrate-gripping behavior demonstrated by the early theropod, in turn, is consistent with the hypothesized function of pedal claws in bird ancestors.

Acetylcholinesterase inhibition and locomotor function after motor-sensory cortex impact injury.

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Holschneider, Daniel P; Guo, Yumei; Roch, Margareth; Norman, Keith M; Scremin, Oscar U

2011-09-01

Traumatic brain injury (TBI) induces transient or persistent dysfunction of gait and balance. Enhancement of cholinergic transmission has been reported to accelerate recovery of cognitive function after TBI, but the effects of this intervention on locomotor activity remain largely unexplored. The hypothesis that enhancement of cholinergic function by inhibition of acetylcholinesterase (AChE) improves locomotion following TBI was tested in Sprague-Dawley male rats after a unilateral controlled cortical impact (CCI) injury of the motor-sensory cortex. Locomotion was tested by time to fall on the constant speed and accelerating Rotarod, placement errors and time to cross while walking through a horizontal ladder, activity monitoring in the home cages, and rearing behavior. Assessments were performed the 1st and 2nd day and the 1st, 2nd, and 3rd week after TBI. The AChE inhibitor physostigmine hemisulfate (PHY) was administered continuously via osmotic minipumps implanted subcutaneously at the rates of 1.6-12.8 μmol/kg/day. All measures of locomotion were impaired by TBI and recovered to initial levels between 1 and 3 weeks post-TBI, with the exception of the maximum speed achievable on the accelerating Rotarod, as well as rearing in the open field. PHY improved performance in the accelerating Rotarod at 1.6 and 3.2 μmol/kg/day (AChE activity 95 and 78% of control, respectively), however, higher doses induced progressive deterioration. No effect or worsening of outcomes was observed at all PHY doses for home cage activity, rearing, and horizontal ladder walking. Potential benefits of cholinesterase inhibition on locomotor function have to be weighed against the evidence of the narrow range of useful doses.

Development and functional organization of spinal locomotor circuits

DEFF Research Database (Denmark)

Kiehn, Ole

2011-01-01

The coordination and timing of muscle activities during rhythmic movements, like walking and swimming, are generated by intrinsic spinal motor circuits. Such locomotor networks are operational early in development and are found in all vertebrates. This review outlines and compares recent advances...

Cognitive deficits and decreased locomotor activity induced by single-walled carbon nanotubes and neuroprotective effects of ascorbic acid

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Liu X

2014-02-01

ascorbic acid. This work suggests SWCNTs could induce cognitive deficits and decreased locomotor activity, and provides a strategy to avoid the adverse effects. Keywords: behavioral changes, oxidative stress, inflammation, apoptosis

Effects of noradrenaline on locomotor rhythm-generating networks in the isolated neonatal rat spinal cord

DEFF Research Database (Denmark)

Kiehn, O; Sillar, K T; Kjaerulff, O

1999-01-01

locomotor-like rhythm, in which activity alternated between the left and right sides, and between rostral and caudal roots on the same side. As shown previously, stable locomotor activity could be induced by bath application of N-methyl-D-aspartate (NMDA; 4-8.5 microM) and/or serotonin (5-HT; 4-20 micro......M). NA modulated this activity by decreasing the cycle frequency and increasing the ventral root burst duration. These effects were dose dependent in the concentration range 1-5 microM. In contrast, at no concentration tested did NA have consistent effects on burst amplitudes or on the background...... activity of the ongoing rhythm. Moreover, NA did not obviously affect the left/right and rostrocaudal alternation of the NMDA/5-HT rhythm. The NMDA/5-HT locomotor rhythm sometimes displayed a time-dependent breakdown in coordination, ultimately resulting in tonic ventral root activity. However...

The role of Homer 1a in increasing locomotor activity and non-selective attention, and impairing learning and memory abilities.

Science.gov (United States)

Yang, Lei; Hong, Qin; Zhang, Min; Liu, Xiao; Pan, Xiao-Qin; Guo, Mei; Fei, Li; Guo, Xi-Rong; Tong, Mei-Ling; Chi, Xia

2013-06-17

The current study aimed to investigate the possible role of Homer 1a in the etiology and pathogenesis of attention deficit hyperactivity disorder (ADHD). We divided 32 rats into four groups. The rats in the RNAi-MPH group were given the lentiviral vector containing Homer 1a-specific miRNA (Homer 1a-RNAi-LV) by intracerebroventricular injection, and 7 days later they were given three daily doses of methylphenidate (MPH) by intragastric gavage. The RNAi-SAL group was given Homer 1a-RNAi-LV and saline later. The NC-MPH group was given the negative control lentiviral vector (NC-LV) and MPH later. The NC-SAL group was given NC-LV and saline later. Rats that were given Homer 1a RNAi exhibited increased locomotor activity and non-selective attention, and impaired learning and memory abilities, which is in line with the behavioral findings of animal models of ADHD. However, MPH ameliorated these abnormal behaviors. All findings indicated that Homer 1a may play an important role in the etiology and pathogenesis of ADHD. Copyright © 2013 Elsevier B.V. All rights reserved.

A rapid enhancement of locomotor sensitization to amphetamine by estradiol in female rats.

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Zovkic, Iva B; McCormick, Cheryl M

2017-11-14

Estradiol moderates the effects of drugs of abuse in both humans and rodents. Estradiol's enhancement of behavioral effects resulting from high (>2.5mg/kg) doses of amphetamine is established in rats; there is less evidence for the role of estradiol in locomotor effects elicited by lower doses, which are less aversive, increase incentive motivation, involve different neural mechanisms than higher doses, and often more readily reveal group differences than do higher doses. Further, the extent to which estradiol is required for the induction versus the expression of sensitization is unknown. To establish a protocol, we replicated the effects of estradiol on locomotor sensitization to amphetamine reported in a previous study that involved a high locomotor-activating dose (1.5mg/kg) of amphetamine, but with a lower dose. Ovariectomized female rats received 5μg of estradiol benzoate (EB) or OIL 30min before each of 5 treatments of 1.0mg/kg amphetamine or saline; all received a 0.5mg/kg challenge dose three days later. Compared with results for OIL, EB enhanced the locomotor-activating effects of repeated 1.0mg/kg amphetamine across treatment days. In contrast, on challenge day, there was no difference between EB-saline and EB-amphetamine to the lower dose (i.e., no sensitization). Experiments 2 and 3 involved a shorter induction (2days) and a lengthier withdrawal (9days) before the challenge test for the expression of sensitization to better differentiate the induction phase from the expression phase. In Expt2, EB-, and not OIL-, treated rats showed sensitization to 0.5mg/kg amphetamine; neither group showed sensitization to 1.5mg/kg amphetamine (ceiling effect?). In Expt3, rats were treated with EB either in both the induction and expression phases, in one of the phases only, or in neither phase. There was an effect of hormone treatment on challenge day and not on induction day; rats given EB on Challenge day showed sensitization to 0.5mg/kg amphetamine; OIL rats did

Protective effects of antidepressants against chronic fatigue syndrome-induced behavioral changes and biochemical alterations.

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Kumar, Anil; Garg, Ruchika

2009-02-01

Chronic fatigue syndrome (CFS) is characterized by profound fatigue, which substantially interferes with daily activities. The aim of this study was to explore the protective effects of antidepressants in an animal model of CFS in mice. Male albino mice were forced to swim individually for a period of 6-min session each for 7 days. Imipramine (10 and 20 mg/kg), desipramine (10 and 20 mg/kg) and citalopram (5 and 10 mg/kg) were administered 30 min before forced swimming test on each day. Various behavior tests (immobility time, locomotor activity, anxiety-like behavior by plus maze and mirror chamber) followed by biochemical parameters (lipid peroxidation, reduced glutathione, catalase and nitrite level) were assessed in chronic stressed mice. Chronic forced swimming for 7 days significantly caused increase in immobility period, impairment in locomotor activity, anxiety-like behavior, and oxidative stress (raised lipid peroxidation, nitrite activity and reduced glutathione and catalase activity) as compared with naïve mice (P immobility time, improved locomotor activity and anti-anxiety effect (in both plus maze and mirror chamber test), and attenuated oxidative stress in chronic stressed mice as compared with control (chronic fatigues) (P < 0.05). These results suggested that these drugs have protective effect and could be used in the management of chronic fatigue like conditions.

Flexibility in the patterning and control of axial locomotor networks in lamprey.

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Buchanan, James T

2011-12-01

In lower vertebrates, locomotor burst generators for axial muscles generally produce unitary bursts that alternate between the two sides of the body. In lamprey, a lower vertebrate, locomotor activity in the axial ventral roots of the isolated spinal cord can exhibit flexibility in the timings of bursts to dorsally-located myotomal muscle fibers versus ventrally-located myotomal muscle fibers. These episodes of decreased synchrony can occur spontaneously, especially in the rostral spinal cord where the propagating body waves of swimming originate. Application of serotonin, an endogenous spinal neurotransmitter known to presynaptically inhibit excitatory synapses in lamprey, can promote decreased synchrony of dorsal-ventral bursting. These observations suggest the possible existence of dorsal and ventral locomotor networks with modifiable coupling strength between them. Intracellular recordings of motoneurons during locomotor activity provide some support for this model. Pairs of motoneurons innervating myotomal muscle fibers of similar ipsilateral dorsoventral location tend to have higher correlations of fast synaptic activity during fictive locomotion than do pairs of motoneurons innervating myotomes of different ipsilateral dorsoventral locations, suggesting their control by different populations of premotor interneurons. Further, these different motoneuron pools receive different patterns of excitatory and inhibitory inputs from individual reticulospinal neurons, conveyed in part by different sets of premotor interneurons. Perhaps, then, the locomotor network of the lamprey is not simply a unitary burst generator on each side of the spinal cord that activates all ipsilateral body muscles simultaneously. Instead, the burst generator on each side may comprise at least two coupled burst generators, one controlling motoneurons innervating dorsal body muscles and one controlling motoneurons innervating ventral body muscles. The coupling strength between these two

Repeated MDMA administration increases MDMA-produced locomotor activity and facilitates the acquisition of MDMA self-administration: role of dopamine D2 receptor mechanisms.

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van de Wetering, Ross; Schenk, Susan

2017-04-01

Repeated exposure to ±3, 4-methylenedioxymethamphetamine (MDMA) produces sensitization to MDMA-produced hyperactivity, but the mechanisms underlying the development of this sensitized response or the relationship to the reinforcing effects of MDMA is unknown. This study determined the effect of a sensitizing regimen of MDMA exposure on the acquisition of MDMA self-administration and investigated the role of dopamine D 2 receptor mechanisms. Rats received the selective D 2 antagonist, eticlopride (0.0 or 0.3 mg/kg, i.p.) and MDMA (0.0 or 10.0 mg/kg, i.p.) during a five-day pretreatment regimen. Two days following the final session, the locomotor activating effects of MDMA (5 mg/kg, i.p.) and the latency to acquisition of MDMA self-administration were determined. Pretreatment with MDMA enhanced the locomotor activating effects of MDMA and facilitated the acquisition of MDMA self-administration. Administration of eticlopride during MDMA pretreatment completely blocked the development of sensitization to MDMA-produced hyperactivity but failed to significantly alter the facilitated acquisition of MDMA self-administration. Pretreatment with eticlopride alone facilitated the acquisition of self-administration. These data suggest that repeated MDMA exposure sensitized both the locomotor activating and reinforcing effects of MDMA. Activation of D 2 receptors during MDMA pretreatment appears critical for the development of sensitization to MDMA-produced hyperactivity. The role of D 2 receptor mechanisms in the development of sensitization to the reinforcing effects of MDMA is equivocal.

Monitoring and Analyzing of Circadian and Ultradian Locomotor Activity Based on Raspberry-Pi

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Vittorio Pasquali

2016-09-01

Full Text Available A new device based on the Raspberry-Pi to monitor the locomotion of Arctic marine invertebrates and to analyze chronobiologic data has been made, tested and deployed. The device uses infrared sensors to monitor and record the locomotor activity of the animals, which is later analyzed. The software package consists of two separate scripts: the first designed to manage the acquisition and the evolution of the experiment, the second designed to generate actograms and perform various analyses to detect periodicity in the data (e.g., Fourier power spectra, chi-squared periodograms, and Lomb–Scargle periodograms. The data acquisition hardware and the software has been previously tested during an Arctic mission with an arctic marine invertebrate.

Distributed plasticity of locomotor pattern generators in spinal cord injured patients.

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Grasso, Renato; Ivanenko, Yuri P; Zago, Myrka; Molinari, Marco; Scivoletto, Giorgio; Castellano, Vincenzo; Macellari, Velio; Lacquaniti, Francesco

2004-05-01

Recent progress with spinal cord injured (SCI) patients indicates that with training they can recover some locomotor ability. Here we addressed the question of whether locomotor responses developed with training depend on re-activation of the normal motor patterns or whether they depend on learning new motor patterns. To this end we recorded detailed kinematic and EMG data in SCI patients trained to step on a treadmill with body-weight support (BWST), and in healthy subjects. We found that all patients could be trained to step with BWST in the laboratory conditions, but they used new coordinative strategies. Patients with more severe lesions used their arms and body to assist the leg movements via the biomechanical coupling of limb and body segments. In all patients, the phase-relationship of the angular motion of the different lower limb segments was very different from the control, as was the pattern of activity of most recorded muscles. Surprisingly, however, the new motor strategies were quite effective in generating foot motion that closely matched the normal in the laboratory conditions. With training, foot motion recovered the shape, the step-by-step reproducibility, and the two-thirds power relationship between curvature and velocity that characterize normal gait. We mapped the recorded patterns of muscle activity onto the approximate rostrocaudal location of motor neuron pools in the human spinal cord. The reconstructed spatiotemporal maps of motor neuron activity in SCI patients were quite different from those of healthy subjects. At the end of training, the locomotor network reorganized at both supralesional and sublesional levels, from the cervical to the sacral cord segments. We conclude that locomotor responses in SCI patients may not be subserved by changes localized to limited regions of the spinal cord, but may depend on a plastic redistribution of activity across most of the rostrocaudal extent of the spinal cord. Distributed plasticity underlies

Neuroprotective role of quercetin in locomotor activities and cholinergic neurotransmission in rats experimentally demyelinated with ethidium bromide.

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Beckmann, Diego V; Carvalho, Fabiano B; Mazzanti, Cinthia M; Dos Santos, Rosmarini P; Andrades, Amanda O; Aiello, Graciane; Rippilinger, Angel; Graça, Dominguita L; Abdalla, Fátima H; Oliveira, Lizielle S; Gutierres, Jessié M; Schetinger, Maria Rosa C; Mazzanti, Alexandre

2014-05-17

The purpose of this study was to investigate whether the flavonoid quercetin can prevent alterations in the behavioral tests and of cholinergic neurotransmission in rats submitted to the ethidium bromide (EB) experimental demyelination model during events of demyelination and remyelination. Wistar rats were randomly distributed into four groups (20 animals per group): Control (pontine saline injection and treatment with ethanol), Querc (pontine saline injection and treatment with quercetin), EB (pontine 0.1% EB injection and treatment with ethanol), and EB+Querc (pontine 0.1% EB injection and treatment with quercetin). The groups Querc and Querc+EB were treated once daily with quercetin (50mg/kg) diluted in 25% ethanol solution (1ml/kg) and the animals of the control and EB groups were treated once daily with 25% ethanol solution (1ml/kg). Two stages were observed: phase of demyelination (peak on day 7) and phase of remyelination (peak on day 21 post-injection). Behavioral tests (beam walking, foot fault and inclined plane test), acetylcholinesterase (AChE) activity and lipid peroxidation in pons, cerebellum, hippocampus, hypothalamus, striatum and cerebral cortex were measured. The quercetin promoted earlier locomotor recovery, suggesting that there was demyelination prevention or further remyelination velocity as well as it was able to prevent the inhibition of AChE activity and the increase of lipidic peroxidation, suggesting that this compound can protect cholinergic neurotransmission. These results may contribute to a better understanding of the neuroprotective role of quercetin and the importance of an antioxidant diet in humans to provide benefits in neurodegenerative diseases such as MS. Copyright © 2014. Published by Elsevier Inc.

Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part 1. Variability of measurement parameters under general test conditions

Energy Technology Data Exchange (ETDEWEB)

Vogl, C.; Grillitsch, B.; Wytek, R.; Spieser, O.H.; Scholz, W.

1999-12-01

An automated, personal computer-based video-processing, object-recognition, and object-tracing system was used to record and analyze undirected spontaneous locomotor behavior of small groups of undisturbed zebra fish (Brachydanio rerio) in laboratory tanks. The primary data provided by the monitoring system were the individually assigned, time-stamped coordinates of the fish in two-dimensional projection. Secondary parameters (position, velocity of movement in the horizontal and the vertical direction, and temporal intraindividual and interindividual association) were calculated. The computed parameters offered a multidimensional description of spontaneous undirected swimming behavior of the fish and proved to be largely independent of water temperature, length, weight, and sex ratio of the zebra fish within the standardized range, but varied significantly with the feeding regime, time of day, number of fish per tank, and batch. Statistical characteristics of the behavioral parameters confirmed them as being appropriate for parametric statistical analyses.

Error signals driving locomotor adaptation

DEFF Research Database (Denmark)

Choi, Julia T; Jensen, Peter; Nielsen, Jens Bo

2016-01-01

Locomotor patterns must be adapted to external forces encountered during daily activities. The contribution of different sensory inputs to detecting perturbations and adapting movements during walking is unclear. Here we examined the role of cutaneous feedback in adapting walking patterns to force...... walking (Choi et al. 2013). Sensory tests were performed to measure cutaneous touch threshold and perceptual threshold of force perturbations. Ankle movement were measured while subjects walked on the treadmill over three periods: baseline (1 min), adaptation (1 min) and post-adaptation (3 min). Subjects...

Locomotor Anatomy and Behavior of Patas Monkeys (Erythrocebus patas with Comparison to Vervet Monkeys (Cercopithecus aethiops

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Adrienne L. Zihlman

2013-01-01

Full Text Available Patas monkeys (Erythrocebus patas living in African savanna woodlands and grassland habitats have a locomotor system that allows them to run fast, presumably to avoid predators. Long fore- and hindlimbs, long foot bones, short toes, and a digitigrade foot posture were proposed as anatomical correlates with speed. In addition to skeletal proportions, soft tissue and whole body proportions are important components of the locomotor system. To further distinguish patas anatomy from other Old World monkeys, a comparative study based on dissection of skin, muscle, and bone from complete individuals of patas and vervet monkeys (Cercopithecus aethiops was undertaken. Analysis reveals that small adjustments in patas skeletal proportions, relative mass of limbs and tail, and specific muscle groups promote efficient sagittal limb motion. The ability to run fast is based on a locomotor system adapted for long distance walking. The patas’ larger home range and longer daily range than those of vervets give them access to highly dispersed, nutritious foods, water, and sleeping trees. Furthermore, patas monkeys have physiological adaptations that enable them to tolerate and dissipate heat. These features all contribute to the distinct adaptation that is the patas monkeys’ basis for survival in grassland and savanna woodland areas.

Motor unit recruitment patterns 1: responses to changes in locomotor velocity and incline.

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Hodson-Tole, Emma F; Wakeling, James M

2008-06-01

Mammalian skeletal muscles are composed of a mixture of motor unit types, which contribute a range of mechanical and physiological properties to the muscle. For a muscle to effectively contribute to smooth, co-ordinated movement it must activate an appropriate number and combination of motor units to generate the required force over a suitable time period. Much evidence exists indicating that motor units are activated in an orderly fashion, from the slowest through to the fastest. A growing body of evidence, however, indicates that such a recruitment strategy does not always hold true. Here we investigate how motor unit recruitment patterns were influenced by changes in locomotor velocity and incline. Kinematics data and myoelectric signals were collected from three rat ankle extensor muscles during running on a treadmill at nine velocity and incline combinations. Wavelet and principal component analysis were used to simultaneously decompose the signals into time and frequency space. The relative frequency components of the signals were quantified during 20 time windows of a stride from each locomotor condition. Differences in signal frequency components existed between muscles and locomotor conditions. Faster locomotor velocities led to a relative increase in high frequency components, whereas greater inclines led to a relative increase in the low frequency components. These data were interpreted as representing changes in motor unit recruitment patterns in response to changes in the locomotor demand. Motor units were not always recruited in an orderly manner, indicating that recruitment is a multi-factorial phenomenon that is not yet fully understood.

Application of the Copenhagen Soccer Test in high-level women players - locomotor activities, physiological response and sprint performance

DEFF Research Database (Denmark)

Bendiksen, Mads; Pettersen, Svein Arne; Ingebrigtsen, Jørgen

2013-01-01

We evaluated the physiological response, sprint performance and technical ability in various phases of the Copenhagen Soccer Test for Women (CSTw) and investigated whether the locomotor activities of the CSTw were comparable to competitive match-play (CM). Physiological measurements and physical....../technical assessments were performed during CSTw for eleven Norwegian high-level women soccer players. The activity pattern during CSTw and CM was monitored using the ZXY tracking system. No differences were observed between CSTw and CM with regards to total distance covered (10093±94 and 9674±191m), high intensity...

Cortisol treatment affects locomotor activity and swimming behaviour of male smallmouth bass engaged in paternal care: A field study using acceleration biologgers.

Science.gov (United States)

Algera, Dirk A; Brownscombe, Jacob W; Gilmour, Kathleen M; Lawrence, Michael J; Zolderdo, Aaron J; Cooke, Steven J

2017-11-01

Paternal care, where the male provides sole care for the developing brood, is a common form of reproductive investment among teleost fish and ubiquitous in the Centrarchidae family. Throughout the parental care period, nesting males expend energy in a variety of swimming behaviours, including routine and burst swimming, vigilantly monitoring the nest area and protecting the brood from predators. Parental care is an energetically demanding period, which is presumably made even more difficult if fish are exposed to additional challenges such as those arising from human disturbance, resulting in activation of the hypothalamic-pituitary-interrenal axis (i.e., elevation of cortisol). To study this situation, we examined the effects of experimental manipulation of the stress hormone cortisol on locomotor activity and behaviour of nest guarding male smallmouth bass (Micropterus dolomieu). We exogenously elevated circulating cortisol levels (via intracoelomic implants) and attached tri-axial accelerometers to wild smallmouth bass for three days. During the recovery period (i.e., ≤4h post-release), cortisol-treated fish exhibited significantly reduced locomotor activity and performed significantly less burst and routine swimming relative to control fish, indicating cortisol uptake was rapid, as were the associated behavioural responses. Post-recovery (i.e., >4h post-release), fish with high cortisol exhibited lower locomotor activity and reduced routine swimming relative to controls. Fish were less active and reduced routine and burst swimming at night compared to daylight hours, an effect independent of cortisol treatment. Collectively, our results suggest that cortisol treatment (as a proxy for anthropogenic disturbance and stress) contributed to altered behaviour, and consequently cortisol-treated males decreased parental investment in their brood, which could have potential fitness implications. Copyright © 2017 Elsevier Inc. All rights reserved.

Chronic exposure to MDMA (Ecstasy elicits behavioral sensitization in rats but fails to induce cross-sensitization to other psychostimulants

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Swann Alan C

2006-01-01

Full Text Available Abstract Background The recreational use of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy among adolescents and young adults has become increasingly prevalent in recent years. While evidence suggests that the long-term consequences of MDMA use include neurodegeneration to serotonergic and, possibly, dopaminergic pathways, little is known about susceptibility, such as behavioral sensitization, to MDMA. Methods The objectives of this study were to examine the dose-response characteristics of acute and chronic MDMA administration in rats and to determine whether MDMA elicits behavioral sensitization and whether it cross-sensitizes with amphetamine and methylphenidate. Adult male Sprague-Dawley rats were randomly divided into three MDMA dosage groups (2.5 mg/kg, 5.0 mg/kg, and 10.0 mg/kg and a saline control group (N = 9/group. All three MDMA groups were treated for six consecutive days, followed by a 5-day washout, and subsequently re-challenged with their respective doses of MDMA (day 13. Rats were then given an additional 25-day washout period, and re-challenged (day 38 with similar MDMA doses as before followed by either 0.6 mg/kg amphetamine or 2.5 mg/kg methylphenidate on the next day (day 39. Open-field locomotor activity was recorded using a computerized automated activity monitoring system. Results Acute injection of 2.5 mg/kg MDMA showed no significant difference in locomotor activity from rats given saline (control group, while animals receiving acute 5.0 mg/kg or 10.0 mg/kg MDMA showed significant increases in locomotor activity. Rats treated chronically with 5.0 mg/kg and 10.0 mg/kg MDMA doses exhibited an augmented response, i.e., behavioral sensitization, on experimental day 13 in at least one locomotor index. On experimental day 38, all three MDMA groups demonstrated sensitization to MDMA in at least one locomotor index. Amphetamine and methylphenidate administration to MDMA-sensitized animals did not elicit any significant change

[Effects of nootropic drugs on behavior of BALB/c and C57BL/6 mice in the exploratory cross-maze test].

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Vasil'eva, E V; Salimov, R M; Kovalev, G I

2012-01-01

Exploratory behavior, locomotor activity, and anxiety in inbred mice of C57BL/6 and BALB/c strains subchronically treated with placebo or various types of nootropic (cognition enhancing) drugs (piracetam, phenotropil, noopept, semax, pantogam, nooglutil) have been evaluated using the exploratory cross-maze test. It was found that BALB/c mice in comparison to C57BL/6 mice are characterized by greater anxiety and lower efficiency of exploratory behavior in the previously unfamiliar environment. All tested drugs clearly improved the exploratory behavior in BALB/c mice only. In BALB/c mice, piracetam, phenotropil, noopept, and semax also reduced anxiety, while phenotropil additionally increased locomotor activity. Thus, the nootropic drugs displayed clear positive modulation of spontaneous orientation in the mice strain with initially low exploratory efficiency (BALB/c) in the cross-maze test. Some drugs (pantogam, nooglutil) exhibited only nootropic properties, while the other drugs exhibited both nootropic effects on the exploratory activity and produced modulation of the anxiety level (piracetam, fenotropil, noopept, semax) and locomotor activity (fenotropil).

Classification of rhythmic locomotor patterns in electromyographic signals using fuzzy sets

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Thrasher Timothy A

2011-12-01

Full Text Available Abstract Background Locomotor control is accomplished by a complex integration of neural mechanisms including a central pattern generator, spinal reflexes and supraspinal control centres. Patterns of muscle activation during walking exhibit an underlying structure in which groups of muscles seem to activate in united bursts. Presented here is a statistical approach for analyzing Surface Electromyography (SEMG data with the goal of classifying rhythmic "burst" patterns that are consistent with a central pattern generator model of locomotor control. Methods A fuzzy model of rhythmic locomotor patterns was optimized and evaluated using SEMG data from a convenience sample of four able-bodied individuals. As well, two subjects with pathological gait participated: one with Parkinson's Disease, and one with incomplete spinal cord injury. Subjects walked overground and on a treadmill while SEMG was recorded from major muscles of the lower extremities. The model was fit to half of the recorded data using non-linear optimization and validated against the other half of the data. The coefficient of determination, R2, was used to interpret the model's goodness of fit. Results Using four fuzzy burst patterns, the model was able to explain approximately 70-83% of the variance in muscle activation during treadmill gait and 74% during overground gait. When five burst functions were used, one function was found to be redundant. The model explained 81-83% of the variance in the Parkinsonian gait, and only 46-59% of the variance in spinal cord injured gait. Conclusions The analytical approach proposed in this article is a novel way to interpret multichannel SEMG signals by reducing the data into basic rhythmic patterns. This can help us better understand the role of rhythmic patterns in locomotor control.

GABAB Receptor Stimulation Accentuates the Locomotor Effects of Morphine in Mice Bred for Extreme Sensitivity to the Stimulant Effects of Ethanol

OpenAIRE

Holstein, Sarah E.; Phillips, Tamara J.

2006-01-01

Mice selectively bred for divergent sensitivity to the locomotor stimulant effects of ethanol (FAST and SLOW) also differ in their locomotor response to morphine. The GABAB receptor has been implicated in the mediation of locomotor stimulation to both ethanol and morphine, and a reduction in ethanol-induced stimulation has been found with the GABAB receptor agonist baclofen in FAST mice. We hypothesized that GABAB receptor activation would also attenuate the locomotor stimulant responses to m...

Cocaine- and amphetamine-regulated transcript peptide in the nucleus accumbens shell inhibits cocaine-induced locomotor sensitization to transient over-expression of α-Ca2+ /calmodulin-dependent protein kinase II.

Science.gov (United States)

Xiong, Lixia; Meng, Qing; Sun, Xi; Lu, Xiangtong; Fu, Qiang; Peng, Qinghua; Yang, Jianhua; Oh, Ki-Wan; Hu, Zhenzhen

2018-01-04

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter that attenuates cocaine-induced locomotor activity when injected into the nucleus accumbens (NAc). Our previous work first confirmed that the inhibitory mechanism of the CART peptide on cocaine-induced locomotor activity is related to a reduction in cocaine-enhanced phosphorylated Ca 2+ /calmodulin-dependent protein kinaseIIα (pCaMKIIα) and the enhancement of cocaine-induced D3R function. This study investigated whether CART peptide inhibited cocaine-induced locomotor activity via inhibition of interactions between pCaMKIIα and the D3 dopamine receptor (D3R). We demonstrated that lentivirus-mediated gene transfer transiently increased pCaMKIIα expression, which peaked at 10 days after microinjection into the rat NAc shell, and induced a significant increase in Ca 2+ influx along with greater behavioral sensitivity in the open field test after intraperitoneal injections of cocaine (15 mg/kg). However, western blot analysis and coimmunoprecipitation demonstrated that CART peptide treatment in lentivirus-transfected CaMKIIα-over-expressing NAc rat tissues or cells prior to cocaine administration inhibited the cocaine-induced Ca 2+ influx and attenuated the cocaine-increased pCaMKIIα expression in lentivirus-transfected CaMKIIα-over-expressing cells. CART peptide decreased the cocaine-enhanced phosphorylated cAMP response element binding protein (pCREB) expression via inhibition of the pCaMKIIα-D3R interaction, which may account for the prolonged locomotor sensitization induced by repeated cocaine treatment in lentivirus-transfected CaMKIIα-over-expressing cells. These results provide strong evidence for the inhibitory modulation of CART peptide in cocaine-induced locomotor sensitization. © 2018 International Society for Neurochemistry.

Locomotor adaptation to a soleus EMG-controlled antagonistic exoskeleton.

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Gordon, Keith E; Kinnaird, Catherine R; Ferris, Daniel P

2013-04-01

Locomotor adaptation in humans is not well understood. To provide insight into the neural reorganization that occurs following a significant disruption to one's learned neuromuscular map relating a given motor command to its resulting muscular action, we tied the mechanical action of a robotic exoskeleton to the electromyography (EMG) profile of the soleus muscle during walking. The powered exoskeleton produced an ankle dorsiflexion torque proportional to soleus muscle recruitment thus limiting the soleus' plantar flexion torque capability. We hypothesized that neurologically intact subjects would alter muscle activation patterns in response to the antagonistic exoskeleton by decreasing soleus recruitment. Subjects practiced walking with the exoskeleton for two 30-min sessions. The initial response to the perturbation was to "fight" the resistive exoskeleton by increasing soleus activation. By the end of training, subjects had significantly reduced soleus recruitment resulting in a gait pattern with almost no ankle push-off. In addition, there was a trend for subjects to reduce gastrocnemius recruitment in proportion to the soleus even though only the soleus EMG was used to control the exoskeleton. The results from this study demonstrate the ability of the nervous system to recalibrate locomotor output in response to substantial changes in the mechanical output of the soleus muscle and associated sensory feedback. This study provides further evidence that the human locomotor system of intact individuals is highly flexible and able to adapt to achieve effective locomotion in response to a broad range of neuromuscular perturbations.

Locomotor adaptation to a soleus EMG-controlled antagonistic exoskeleton

Science.gov (United States)

Kinnaird, Catherine R.; Ferris, Daniel P.

2013-01-01

Locomotor adaptation in humans is not well understood. To provide insight into the neural reorganization that occurs following a significant disruption to one's learned neuromuscular map relating a given motor command to its resulting muscular action, we tied the mechanical action of a robotic exoskeleton to the electromyography (EMG) profile of the soleus muscle during walking. The powered exoskeleton produced an ankle dorsiflexion torque proportional to soleus muscle recruitment thus limiting the soleus' plantar flexion torque capability. We hypothesized that neurologically intact subjects would alter muscle activation patterns in response to the antagonistic exoskeleton by decreasing soleus recruitment. Subjects practiced walking with the exoskeleton for two 30-min sessions. The initial response to the perturbation was to “fight” the resistive exoskeleton by increasing soleus activation. By the end of training, subjects had significantly reduced soleus recruitment resulting in a gait pattern with almost no ankle push-off. In addition, there was a trend for subjects to reduce gastrocnemius recruitment in proportion to the soleus even though only the soleus EMG was used to control the exoskeleton. The results from this study demonstrate the ability of the nervous system to recalibrate locomotor output in response to substantial changes in the mechanical output of the soleus muscle and associated sensory feedback. This study provides further evidence that the human locomotor system of intact individuals is highly flexible and able to adapt to achieve effective locomotion in response to a broad range of neuromuscular perturbations. PMID:23307949

Inhibition of GABA synthesis in the prefrontal cortex increases locomotor activity but does not affect attention in the 5-choice serial reaction time task.

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Asinof, Samuel K; Paine, Tracie A

2013-02-01

Attention deficits are a core cognitive symptom of schizophrenia; the neuropathology underlying these deficits is not known. Attention is regulated, at least in part, by the prefrontal cortex (PFC), a brain area in which pathology of γ-aminobutyric acid (GABA) neurons has been consistently observed in post-mortem analysis of the brains of people with schizophrenia. Specifically, expression of the 67-kD isoform of the GABA synthesis enzyme glutamic acid decarboxylase (GAD67) is reduced in parvalbumin-containing fast-spiking GABA interneurons. Thus it is hypothesized that reduced cortical GABA synthesis and release may contribute to the attention deficits in schizophrenia. Here the effect of reducing cortical GABA synthesis with l-allylglycine (LAG) on attention was tested using three different versions of the 5-choice serial reaction time task (5CSRTT). Because 5CSRTT performance can be affected by locomotor activity, we also measured this behavior in an open field. Finally, the expression of Fos protein was used as an indirect measure of reduced GABA synthesis. Intra-cortical LAG (10 μg/0.5 μl/side) infusions increased Fos expression and resulted in hyperactivity in the open field. Intra-cortical LAG infusions did not affect attention in any version of the 5CSRTT. These results suggest that a general decrease in GABA synthesis is not sufficient to cause attention deficits. It remains to be tested whether a selective decrease in GABA synthesis in parvalbumin-containing GABA neurons could cause attention deficits. Decreased cortical GABA synthesis did increase locomotor activity; this may reflect the positive symptoms of schizophrenia. Copyright © 2012 Elsevier Ltd. All rights reserved.

Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior

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Pendergast, Julie S.; Branecky, Katrina L.; Huang, Roya; Niswender, Kevin D.; Yamazaki, Shin

2014-01-01

Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits. PMID:24624109

The influence of the hot water extract from shiitake medicinal mushroom, Lentinus edodes (higher Basidiomycetes) on the food intake, life span, and age-related locomotor activity of Drosophila melanogaster.

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Matjuskova, Natalya; Azena, Elena; Serstnova, Ksenija; Muiznieks, Indrikis

2014-01-01

Shiitake medicinal mushroom, Lentinus edodes, is among the most widely cultivated edible mushrooms in the world and is a well-studied source of nutrients and biologically active compounds. We have studied the influence of the dietary supplement of the polysaccharides containing a hot water extract of the mushroom L. edodes on the fruit fly Drosophila melanogaster in terms of food intake, body weight, life span, and age-related locomotor activity. L. edodes extract, when added to the D. melanogaster feeding substrate at a 0.003-0.030% concentration (calculated for the dry weight of the polysaccharide fraction) did not influence food intake or body weight of the flies. It increased the life span and locomotor activities of male flies but was associated with early mortality and decreased locomotor activity of female flies. We conclude that the observed anti-aging effects of L. edodes extracts in the male D. melanogaster are not the result of dietary restriction. We propose that D. melanogaster is a suitable model organism for researching the molecular basis of the anti-aging effect of the shiitake mushroom extracts and sex linkage of these effects.

Effect of electron radiation on aggressive behavior, activity, and hemopoiesis in mice

International Nuclear Information System (INIS)

Maier, D.M.; Landauer, M.R.; Davis, H.D.; Walden, T.L.

1989-01-01

The behavioral and physiological effects of 10 Gray (Gy) LINAC electrons in male Swiss-Webster mice were followed for 12 days postirradiation (PR). In Experiment 1, aggressive behavior was assessed in irradiated or sham-irradiated resident mice using a resident-intruder paradigm. Aggressive offensive behavior in the irradiated residents was significantly decreased beginning 2 to 5 days PR, and remained suppressed. Defensive behavior in the nonirradiated intruders was decreased significantly by day 5 PR. In Experiment 2, spontaneous locomotor activity was monitored. Ambulation of irradiated mice was significantly depressed from day 5 PR on, while rearing was affected as early as day 2 PR and remained suppressed. Body weights of irradiated animals were significantly decreased by 5 days PR. In Experiment 3, blood parameters were examined. Compared to sham-irradiated controls, leukocytes, erythrocytes, and hematocrit of irradiated mice were reduced significantly beginning on day 1 PR and remained suppressed, while platelets and hemoglobin were decreased beginning day 2 PR. These results demonstrate that 10 Gy of high-energy electrons results in earlier behavioral deficits than has been observed previously with the same dose of gamma photons. (author)

PROBLEMAS LOCOMOTORES EM FRANGOS DE CORTE - REVISÃO. / LOCOMOTOR PROBLEMS IN BROILER CHICKENS - A REVIEW.

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IBIARA CORREIA DE LIMA ALMEIDA PAZ

2008-12-01

Full Text Available O bem estar animal é, sem dúvida, um dos pontos em que os produtores de aves devem se atentar para conseguir melhor rentabilidade e colocação no mercado externo. No entanto, é necessário ter uma ampla idéia de que alguns pontos impostos por mercados importadores, muitas vezes não tem fundamento científico e tratam-se mais de barreiras não tarifárias que de problemas de produção propriamente ditos. Dentre os vários fatores que afetam o bem estar animal pode-se destacar a incidência de problemas locomotores, principalmente em animais confinados. Estes distúrbios podem acarretar em perdas de até 6% em lotes comercias de frangos de corte, além de outras perdas não mensuráveis em linhas de abate, por fraturas e hematomas. Existem diversas metodologias para diagnosticar problemas locomotores, entretanto, a mais difundida na indústria avícola é o Gait Score, por sua facilidade de aplicação e por englobar os diferentes tipos de problemas locomotores. Sabe-se, contudo que esta metodologia é bastante subjetiva e pode inferir  em  diferentes  níveis  de  avaliação  dependendo  do método  utilizado. Os  problemas locomotores devem ser prevenidos já que depois de estabelecidos as perdas são inevitáveis.

Nanomolar oxytocin synergizes with weak electrical afferent stimulation to activate the locomotor CpG of the rat spinal cord in vitro.

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Francesco Dose

Full Text Available Synergizing the effect of afferent fibre stimulation with pharmacological interventions is a desirable goal to trigger spinal locomotor activity, especially after injury. Thus, to better understand the mechanisms to optimize this process, we studied the role of the neuropeptide oxytocin (previously shown to stimulate locomotor networks on network and motoneuron properties using the isolated neonatal rat spinal cord. On motoneurons oxytocin (1 nM-1 μM generated sporadic bursts with superimposed firing and dose-dependent depolarization. No desensitization was observed despite repeated applications. Tetrodotoxin completely blocked the effects of oxytocin, demonstrating the network origin of the responses. Recording motoneuron pool activity from lumbar ventral roots showed oxytocin mediated depolarization with synchronous bursts, and depression of reflex responses in a stimulus and peptide-concentration dependent fashion. Disinhibited bursting caused by strychnine and bicuculline was accelerated by oxytocin whose action was blocked by the oxytocin antagonist atosiban. Fictive locomotion appeared when subthreshold concentrations of NMDA plus 5HT were coapplied with oxytocin, an effect prevented after 24 h incubation with the inhibitor of 5HT synthesis, PCPA. When fictive locomotion was fully manifested, oxytocin did not change periodicity, although cycle amplitude became smaller. A novel protocol of electrical stimulation based on noisy waveforms and applied to one dorsal root evoked stereotypic fictive locomotion. Whenever the stimulus intensity was subthreshold, low doses of oxytocin triggered fictive locomotion although oxytocin per se did not affect primary afferent depolarization evoked by dorsal root pulses. Among the several functional targets for the action of oxytocin at lumbar spinal cord level, the present results highlight how small concentrations of this peptide could bring spinal networks to threshold for fictive locomotion in

Enhanced tethered-flight duration and locomotor activity by overexpression of the human gene SOD1 in Drosophila motorneurons

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Agavni Petrosyan

2015-03-01

Full Text Available Mutation of the human gene superoxide dismutase (hSOD1 is associated with the fatal neurodegenerative disease familial amyotrophic lateral sclerosis (Lou Gehrig’s disease. Selective overexpression of hSOD1 in Drosophila motorneurons increases lifespan to 140% of normal. The current study was designed to determine resistance to lifespan decline and failure of sensorimotor functions by overexpressing hSOD1 in Drosophila‘s motorneurons. First, we measured the ability to maintain continuous flight and wingbeat frequency (WBF as a function of age (5 to 50 days. Flies overexpressing hSOD1 under the D42-GAL4 activator were able to sustain flight significantly longer than controls, with the largest effect observed in the middle stages of life. The hSOD1-expressed line also had, on average, slower wingbeat frequencies in late, but not early life relative to age-matched controls. Second, we examined locomotor (exploratory walking behavior in late life when flies had lost the ability to fly (age ≥ 60 d. hSOD1-expressed flies showed significantly more robust walking activity relative to controls. Findings show patterns of functional decline dissimilar to those reported for other life-extended lines, and suggest that the hSOD1 gene not only delays death but enhances sensorimotor abilities critical to survival even in late life.

Oral and transdermal DL-methylphenidate-ethanol interactions in C57BL/6J mice: potentiation of locomotor activity with oral delivery.

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Bell, Guinevere H; Griffin, William C; Patrick, Kennerly S

2011-12-01

Many abusers of dl-methylphenidate co-abuse ethanol. The present animal study examined behavioral effects of oral or transdermal DL-methylphenidate in combination with a high, depressive dose of ethanol to model co-abuse. Locomotor activity of C57BL/6J mice was recorded for 3 h following dosing with either oral DL-methylphenidate (7.5 mg/kg) or transdermal DL-methylphenidate (Daytrana®;1/4 of a 12.5 cm(2) patch; mean dose 7.5 mg/kg), with or without oral ethanol (3 g/kg). Brains were enantiospecifically analyzed for the isomers of methylphenidate and the transesterification metabolite ethylphenidate. An otherwise depressive dose of ethanol significantly potentiated oral DL-methylphenidate induced increases in total distance traveled for the first 100 min (pbrain D-methylphenidate concentrations were significantly elevated by ethanol in both the oral (65% increase) and transdermal (88% increase) groups. The corresponding L-ethylphenidate concentrations were 10 ng/g and 130 ng/g. Stimulant induced motor activity in rodents may correlate with abuse liability. Potentiation of DL-methylphenidate motor effects by concomitant ethanol carries implications regarding increased abuse potential of DL-methylphenidate when combined with ethanol. Copyright © 2011 Elsevier Inc. All rights reserved.

Frontal brain activity and behavioral indicators of affective states are weakly affected by thermal stimuli in sheep living in different housing conditions

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Sabine eVögeli

2015-05-01

Full Text Available Many stimuli evoke short-term emotional reactions. These reactions may play an important role in assessing how a subject perceives a stimulus. Additionally, long-term mood may modulate the emotional reactions but it is still unclear in what way. The question seems to be important in terms of animal welfare, as a negative mood may taint emotional reactions. In the present study with sheep, we investigated the effects of thermal stimuli on emotional reactions and the potential modulating effect of mood induced by manipulations of the housing conditions. We assume that unpredictable, stimulus-poor conditions lead to a negative and predictable, stimulus-rich conditions to a positive mood state. The thermal stimuli were applied to the upper breast during warm ambient temperatures: hot (as presumably negative, intermediate, and cold (as presumably positive. We recorded cortical activity by functional near-infrared spectroscopy, restlessness behavior (e.g. locomotor activity, aversive behaviors and ear postures as indicators of emotional reactions. The strongest hemodynamic reaction was found during a stimulus of intermediate valence independent of the animal’s housing conditions, whereas locomotor activity, ear movements and aversive behaviors were seen most in sheep from the unpredictable, stimulus-poor housing conditions, independent of stimulus valence. We conclude that, sheep perceived the thermal stimuli and differentiated between some of them. An adequate interpretation of the neuronal activity pattern remains difficult, though. The effects of housing conditions were small indicating that the induction of mood was only modestly efficacious. Therefore, a modulating effect of mood on the emotional reaction was not found.

Comprehensive Behavioral Analysis of Activating Transcription Factor 5-Deficient Mice

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Mariko Umemura

2017-07-01

Full Text Available Activating transcription factor 5 (ATF5 is a member of the CREB/ATF family of basic leucine zipper transcription factors. We previously reported that ATF5-deficient (ATF5-/- mice demonstrated abnormal olfactory bulb development due to impaired interneuron supply. Furthermore, ATF5-/- mice were less aggressive than ATF5+/+ mice. Although ATF5 is widely expressed in the brain, and involved in the regulation of proliferation and development of neurons, the physiological role of ATF5 in the higher brain remains unknown. Our objective was to investigate the physiological role of ATF5 in the higher brain. We performed a comprehensive behavioral analysis using ATF5-/- mice and wild type littermates. ATF5-/- mice exhibited abnormal locomotor activity in the open field test. They also exhibited abnormal anxiety-like behavior in the light/dark transition test and open field test. Furthermore, ATF5-/- mice displayed reduced social interaction in the Crawley’s social interaction test and increased pain sensitivity in the hot plate test compared with wild type. Finally, behavioral flexibility was reduced in the T-maze test in ATF5-/- mice compared with wild type. In addition, we demonstrated that ATF5-/- mice display disturbances of monoamine neurotransmitter levels in several brain regions. These results indicate that ATF5 deficiency elicits abnormal behaviors and the disturbance of monoamine neurotransmitter levels in the brain. The behavioral abnormalities of ATF5-/- mice may be due to the disturbance of monoamine levels. Taken together, these findings suggest that ATF5-/- mice may be a unique animal model of some psychiatric disorders.

Locomotor sensitization to intermittent ketamine administration is associated with nucleus accumbens plasticity in male and female rats.

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Strong, C E; Schoepfer, K J; Dossat, A M; Saland, S K; Wright, K N; Kabbaj, M

2017-07-15

Clinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and conditioned place preference (CPP) were assayed to evaluate behavioral sensitization to the locomotor activating effects of ketamine and its rewarding properties, respectively. Our results show that while neither males nor females developed CPP, males treated with 5 mg/kg and females treated with either 2.5 or 5 mg/kg ketamine behaviorally sensitized. Furthermore, dendritic spine density was increased in the NAc of both males and females administered 5 mg/kg ketamine, an effect specific to the NAc shell (NAcSh) in males but to both the NAc core (NAcC) and NAcSh in females. Additionally, males administered 5 mg/kg ketamine displayed increased protein expression of ΔfosB, calcium calmodulin kinase II alpha (CaMKIIα), and brain-derived neurotrophic factor (BDNF), an effect not observed in females administered either dose of ketamine. However, males and females administered 5 mg/kg ketamine displayed increased protein expression of AMPA receptors (GluA1). Taken together, low-dose ketamine, when administered intermittently, induces behavioral sensitization at a lower dose in females than males, accompanied by an increase in spine density in the NAc and protein expression changes in pathways commonly implicated in addiction. Copyright © 2017. Published by Elsevier Ltd.

Determinants of locomotor disability in people aged 55 years and over: The Rotterdam study

International Nuclear Information System (INIS)

Odding, Else; Valkenburg, Hans A.; Stam, Hendrik J.; Hofman, Albert

2001-01-01

Locomotor disability, as defined by difficulties in activities of daily living related to lower limb function, can be the consequence of diseases and impairments of the cardiovascular, pulmonary, nervous, sensory and musculoskeletal system. We estimated the associations between specific diseases and impairments and locomotor disability, and the proportion of disability attributable to each condition, controlling for age and comorbidity. The Rotterdam Study is a prospective follow-up study among people aged 55 years and over in the general population. Locomotor disability in 1219 men and 1856 women was assessed with the Stanford Health Assessment Questionnaire. Diseases and impairments were radiological osteoarthritis, pain of the hips and knees, morning stiffness, fractures, hypertension, vascular disease, ischemic heart disease, stroke, heart failure, chronic obstructive pulmonary disease (COPD), depression, Parkinson's disease, osteoporosis, diabetes mellitus, overweight, and low vision. Adjusted odds ratios, etiologic and attributable fractions were calculated for locomotor disability. The occurrence of locomotor disability can partly be ascribed to joint pain, COPD, morning stiffness, diabetes and heart failure in both men and women. In addition in women osteoarthritis, osteoporosis, low vision, fractures, stroke and Parkinson's disease are significant etiologic fractions. In men with morning stiffness, joint pain, heart failure, diabetes mellitus, and COPD a significant proportion of their disability is attributable to this impairment. In women this was the case for Parkinson's disease, morning stiffness, low vision, heart failure, joint pain, diabetes, radiological osteoarthritis, stroke, COPD, osteoporosis, and fractures of the lower limbs, in that order. We conclude that locomotor complaints, heart failure, COPD and diabetes mellitus contribute considerably to locomotor disability in non-institutionalized elderly people

Human spinal locomotor control is based on flexibly organized burst generators.

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Danner, Simon M; Hofstoetter, Ursula S; Freundl, Brigitta; Binder, Heinrich; Mayr, Winfried; Rattay, Frank; Minassian, Karen

2015-03-01

Constant drive provided to the human lumbar spinal cord by epidural electrical stimulation can cause local neural circuits to generate rhythmic motor outputs to lower limb muscles in people paralysed by spinal cord injury. Epidural spinal cord stimulation thus allows the study of spinal rhythm and pattern generating circuits without their configuration by volitional motor tasks or task-specific peripheral feedback. To reveal spinal locomotor control principles, we studied the repertoire of rhythmic patterns that can be generated by the functionally isolated human lumbar spinal cord, detected as electromyographic activity from the legs, and investigated basic temporal components shared across these patterns. Ten subjects with chronic, motor-complete spinal cord injury were studied. Surface electromyographic responses to lumbar spinal cord stimulation were collected from quadriceps, hamstrings, tibialis anterior, and triceps surae in the supine position. From these data, 10-s segments of rhythmic activity present in the four muscle groups of one limb were extracted. Such samples were found in seven subjects. Physiologically adequate cycle durations and relative extension- and flexion-phase durations similar to those needed for locomotion were generated. The multi-muscle activation patterns exhibited a variety of coactivation, mixed-synergy and locomotor-like configurations. Statistical decomposition of the electromyographic data across subjects, muscles and samples of rhythmic patterns identified three common temporal components, i.e. basic or shared activation patterns. Two of these basic patterns controlled muscles to contract either synchronously or alternatingly during extension- and flexion-like phases. The third basic pattern contributed to the observed muscle activities independently from these extensor- and flexor-related basic patterns. Each bifunctional muscle group was able to express both extensor- and flexor-patterns, with variable ratios across the

Injections of the selective adenosine A2A antagonist MSX-3 into the nucleus accumbens core attenuate the locomotor suppression induced by haloperidol in rats.

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Ishiwari, Keita; Madson, Lisa J; Farrar, Andrew M; Mingote, Susana M; Valenta, John P; DiGianvittorio, Michael D; Frank, Lauren E; Correa, Merce; Hockemeyer, Jörg; Müller, Christa; Salamone, John D

2007-03-28

There is considerable evidence of interactions between adenosine A2A receptors and dopamine D2 receptors in striatal areas, and antagonists of the A2A receptor have been shown to reverse the motor effects of DA antagonists in animal models. The D2 antagonist haloperidol produces parkinsonism in humans, and also induces motor effects in rats, such as suppression of locomotion. The present experiments were conducted to study the ability of the adenosine A2A antagonist MSX-3 to reverse the locomotor effects of acute or subchronic administration of haloperidol in rats. Systemic (i.p.) injections of MSX-3 (2.5-10.0 mg/kg) were capable of attenuating the suppression of locomotion induced by either acute or repeated (i.e., 14 day) administration of 0.5 mg/kg haloperidol. Bilateral infusions of MSX-3 directly into the nucleus accumbens core (2.5 microg or 5.0 microg in 0.5 microl per side) produced a dose-related increase in locomotor activity in rats treated with 0.5 mg/kg haloperidol either acutely or repeatedly. There were no overall significant effects of MSX-3 infused directly into the dorsomedial nucleus accumbens shell or the ventrolateral neostriatum. These results indicate that antagonism of adenosine A2A receptors can attenuate the locomotor suppression produced by DA antagonism, and that this effect may be at least partially mediated by A2A receptors in the nucleus accumbens core. These studies suggest that adenosine and dopamine systems interact to modulate the locomotor and behavioral activation functions of nucleus accumbens core.

Genotype modulates testosterone-dependent activity and reactivity in male mice.

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Broida, J; Svare, B

1983-03-01

Adult castration significantly reduced the homecage locomotor activity of both inbred C57BL/6J and DBA/2J and outbred Rockland-Swiss (R-S) male mice. Castrated C57BL animals exhibited greater reductions in this behavior than did the other genotypes. Locomotor activity in a novel environment (reactivity) was also reduced by castration but only for inbred males. In both test situations, postcastration reductions in ambulation were prevented by implants of testosterone (T)-containing Silastic capsules. Thus, testicular hormones promote activity and reactivity in the male mouse in a genotype-dependent fashion.

The sublethal effects of endosulfan on the circadian rhythms and locomotor activity of two sympatric parasitoid species.

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Delpuech, Jean-Marie; Bussod, Sophie; Amar, Aurelien

2015-08-01

The organochlorine insecticide endosulfan is dispersed worldwide and significantly contributes to environmental pollution. It is an antagonist of the neurotransmitter gamma-aminobutyric acid (GABA), which is also indirectly involved in photoperiodic time measurement. In this study, we show that endosulfan at a dose as low as LC 0.1 modified the rhythm of locomotor activity of two sympatric parasitoid species, Leptopilina boulardi and Leptopilina heterotoma. The insecticide strongly increased the nocturnal activity of both species and synchronized their diurnal activity; these activities were not synchronized under control conditions. Parasitoids are important species in ecosystems because they control the populations of other insects. In this paper, we discuss the possible consequences of these sublethal effects and highlight the importance of such effects in evaluating the consequences of environmental pollution due to insecticides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of locomotor behaviour between white-headed langurs Trachypithecus leucocephalus and François’ langurs T. françoisi in Fusui, China

OpenAIRE

Jinrong XIONG; Shihua GONG; Chenggang QIU; Zhaoyuan LI

2009-01-01

We studied the locomotor behaviour of white-headed langurs Trachypithecus leucocephalus and François’ langurs T.françoisi to test two hypotheses: (1) these monkeys have evolved locomotor ability to support their activities on limestone hills, and (2) François’ langurs have evolved more diverse locomotor skills than white-headed langurs. Data were collected from 1996–1998 and in 2005 in Fusui Nature Reserve, Guangxi, and showed that the two species had similar locomotor types, but François’ l...

Effects of chronic prenatal MK-801 treatment on object recognition, cognitive flexibility, and drug-induced locomotor activity in juvenile and adult rat offspring.

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Gallant, S; Welch, L; Martone, P; Shalev, U

2017-06-15

Patients with schizophrenia display impaired cognitive functioning and increased sensitivity to psychomimetic drugs. The neurodevelopmental hypothesis of schizophrenia posits that disruption of the developing brain predisposes neural networks to lasting structural and functional abnormalities resulting in the emergence of such symptoms in adulthood. Given the critical role of the glutamatergic system in early brain development, we investigated whether chronic prenatal exposure to the glutamate NMDA receptor antagonist, MK-801, induces schizophrenia-like behavioural and neurochemical changes in juvenile and adult rats. Pregnant Long-Evans rats were administered saline or MK-801 (0.1mg/kg; s.c.) at gestation day 7-19. Object recognition memory and cognitive flexibility were assessed in the male offspring using a novel object preference task and a maze-based set-shifting procedure, respectively. Locomotor-activating effects of acute amphetamine and MK-801 were also assessed. Adult, but not juvenile, prenatally MK-801-treated rats failed to show novel object preference after a 90min delay, suggesting that object recognition memory may have been impaired. In addition, the set-shifting task revealed impaired acquisition of a new rule in adult prenatally MK-801-treated rats compared to controls. This deficit appeared to be driven by regression to the previously learned behaviour. There were no significant differences in drug-induced locomotor activity in juvenile offspring or in adult offspring following acute amphetamine challenges. Unexpectedly, MK-801-induced locomotor activity in adult prenatally MK-801-treated rats was lower compared to controls. Glutamate transmission dysfunction during early development may modify behavioural parameters in adulthood, though these parameters do not appear to model deficits observed in schizophrenia. Copyright © 2017 Elsevier B.V. All rights reserved.

Metabolic activation of amygdala, lateral septum and accumbens circuits during food anticipatory behavior.

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Olivo, Diana; Caba, Mario; Gonzalez-Lima, Francisco; Rodríguez-Landa, Juan F; Corona-Morales, Aleph A

2017-01-01

When food is restricted to a brief fixed period every day, animals show an increase in temperature, corticosterone concentration and locomotor activity for 2-3h before feeding time, termed food anticipatory activity. Mechanisms and neuroanatomical circuits responsible for food anticipatory activity remain unclear, and may involve both oscillators and networks related to temporal conditioning. Rabbit pups are nursed once-a-day so they represent a natural model of circadian food anticipatory activity. Food anticipatory behavior in pups may be associated with neural circuits that temporally anticipate feeding, while the nursing event may produce consummatory effects. Therefore, we used New Zealand white rabbit pups entrained to circadian feeding to investigate the hypothesis that structures related to reward expectation and conditioned emotional responses would show a metabolic rhythm anticipatory of the nursing event, different from that shown by structures related to reward delivery. Quantitative cytochrome oxidase histochemistry was used to measure regional brain metabolic activity at eight different times during the day. We found that neural metabolism peaked before nursing, during food anticipatory behavior, in nuclei of the extended amygdala (basolateral, medial and central nuclei, bed nucleus of the stria terminalis), lateral septum and accumbens core. After pups were fed, however, maximal metabolic activity was expressed in the accumbens shell, caudate, putamen and cortical amygdala. Neural and behavioral activation persisted when animals were fasted by two cycles, at the time of expected nursing. These findings suggest that metabolic activation of amygdala-septal-accumbens circuits involved in temporal conditioning may contribute to food anticipatory activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Trace Amine-Associated Receptor 1 Modulates the Locomotor and Sensitization Effects of Nicotine

Science.gov (United States)

Sukhanov, Ilya; Dorofeikova, Mariia; Dolgorukova, Antonina; Dorotenko, Artem; Gainetdinov, Raul R.

2018-01-01

Trace amine-associated receptor 1 (TAAR1) has emerged as a promising target for addiction treatments because it affects dopamine transmission in the mesolimbic pathway. TAAR1 is involved in the effects of addictive drugs, such as amphetamines, cocaine and ethanol, but the impact of TAAR1 on the effects of nicotine, the psychoactive drug responsible for the development and maintenance of tobacco smoking, has not yet been studied. This study was performed to investigate the possible modulatory action of TAAR1 on the effects of nicotine on locomotor behaviors in rats and mice. Pretreatment with the TAAR1 agonist RO5263397 dose-dependently decreased nicotine-induced hyperlocomotion in rats habituated to locomotor boxes, prevented the development of nicotine sensitization and blocked hypermotility in nicotine-sensitized rats at the highest tested dose (10 mg/kg). The lack of TAAR1 failed to affect the effects of nicotine on the locomotion of mutant mice. Based on the results of the present study, TAAR1 activation attenuates the locomotion-stimulating effects of nicotine on rats. These results further support the previously proposed hypothesis that TAAR1 is a promising target for the prevention and treatment of drug addiction. Further studies aimed at analyzing the effects of TAAR1 agonists on animal models of nicotine addiction are warranted. PMID:29681856

Trace Amine-Associated Receptor 1 Modulates the Locomotor and Sensitization Effects of Nicotine

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Ilya Sukhanov

2018-04-01

Full Text Available Trace amine-associated receptor 1 (TAAR1 has emerged as a promising target for addiction treatments because it affects dopamine transmission in the mesolimbic pathway. TAAR1 is involved in the effects of addictive drugs, such as amphetamines, cocaine and ethanol, but the impact of TAAR1 on the effects of nicotine, the psychoactive drug responsible for the development and maintenance of tobacco smoking, has not yet been studied. This study was performed to investigate the possible modulatory action of TAAR1 on the effects of nicotine on locomotor behaviors in rats and mice. Pretreatment with the TAAR1 agonist RO5263397 dose-dependently decreased nicotine-induced hyperlocomotion in rats habituated to locomotor boxes, prevented the development of nicotine sensitization and blocked hypermotility in nicotine-sensitized rats at the highest tested dose (10 mg/kg. The lack of TAAR1 failed to affect the effects of nicotine on the locomotion of mutant mice. Based on the results of the present study, TAAR1 activation attenuates the locomotion-stimulating effects of nicotine on rats. These results further support the previously proposed hypothesis that TAAR1 is a promising target for the prevention and treatment of drug addiction. Further studies aimed at analyzing the effects of TAAR1 agonists on animal models of nicotine addiction are warranted.

Modification of the effects of 5-methoxy-N,N-dimethyltryptamine on exploratory behavior in rats by monoamine oxidase inhibitors

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Halberstadt, Adam L.; Buell, Mahalah R.; Masten, Virginia L.; Risbrough, Victoria B.; Geyer, Mark A.

2010-01-01

RATIONALE The hallucinogenic tea known as ayahuasca is made from a combination of psychoactive plants that contribute the active components N,N-dimethyltryptamine (DMT) and 5-methoxy-DMT (5-MeO-DMT), as well as the monoamine oxidase (MAO) inhibitors (MAOIs) harmine and harmaline for oral activity. OBJECTIVE The present study examined the effects of 5-MeO-DMT in combination with MAOIs in rats using the Behavioral Pattern Monitor (BPM), which enables analyses of patterns of locomotor activity and exploration. Interaction studies using the serotonin (5-HT)1A antagonist WAY-100635 (1.0 mg/kg) and the 5-HT2A antagonist MDL 11,939 (1.0 mg/kg) were also performed to assess the respective contributions of these receptors to the behavioral effects of 5-MeO-DMT in MAOI-treated animals. RESULTS 5-MeO-DMT (0.01, 0.1, and 1.0 mg/kg) decreased locomotor activity and investigatory behavior. In rats pretreated with a behaviorally inactive dose of harmaline (0.1 mg/kg), 1.0 mg/kg 5-MeO-DMT had biphasic effects on locomotor activity, initially reducing locomotion and then increasing activity as time progressed. The ability of harmaline to shift 5-MeO-DMT to a biphasic locomotor pattern was shared by the selective MAOA inhibitor clorgyline, whereas the selective MAOB inhibitor (−)-deprenyl was ineffective. The late hyperactivity induced by the combination of 1.0 mg/kg 5-MeO-DMT and 0.3 mg/kg clorgyline was blocked by pretreatment with MDL 11,939. Pretreatment with WAY-100635 failed to attenuate either the early hypoactivity or the late hyperactivity. CONCLUSIONS The ability of harmaline to modify the behavioral effects of 5-MeO-DMT is mediated by inhibition of MAOA. Further, 5-HT2A receptors are responsible for the late hyperactivity induced by 5-MeO-DMT in the presence of MAOA inhibitors. PMID:18604652

Development of Testing Methodologies to Evaluate Postflight Locomotor Performance

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Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Richards, J. T.; Miller, C. A.; Brady, R.; Warren, L. E.; Bloomberg, J. J.

2006-01-01

Crewmembers experience locomotor and postural instabilities during ambulation on Earth following their return from space flight. Gait training programs designed to facilitate recovery of locomotor function following a transition to a gravitational environment need to be accompanied by relevant assessment methodologies to evaluate their efficacy. The goal of this paper is to demonstrate the operational validity of two tests of locomotor function that were used to evaluate performance after long duration space flight missions on the International Space Station (ISS).

Eating high fat chow decreases dopamine clearance in adolescent and adult male rats but selectively enhances the locomotor stimulating effects of cocaine in adolescents.

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Baladi, Michelle G; Horton, Rebecca E; Owens, William A; Daws, Lynette C; France, Charles P

2015-03-24

Feeding conditions can influence dopamine neurotransmission and impact behavioral and neurochemical effects of drugs acting on dopamine systems. This study examined whether eating high fat chow alters the locomotor effects of cocaine and dopamine transporter activity in adolescent (postnatal day 25) and adult (postnatal day 75) male Sprague-Dawley rats. Dose-response curves for cocaine-induced locomotor activity were generated in rats with free access to either standard or high fat chow or restricted access to high fat chow (body weight matched to rats eating standard chow). Compared with eating standard chow, eating high fat chow increased the sensitivity of adolescent, but not adult, rats to the acute effects of cocaine. When tested once per week, sensitization to the locomotor effects of cocaine was enhanced in adolescent rats eating high fat chow compared with adolescent rats eating standard chow. Sensitization to cocaine was not different among feeding conditions in adults. When adolescent rats that previously ate high fat chow ate standard chow, sensitivity to cocaine returned to normal. As measured by chronoamperometry, dopamine clearance rate in striatum was decreased in both adolescent and adult rats eating high fat chow compared with age-matched rats eating standard chow. These results suggest that high fat diet-induced reductions in dopamine clearance rate do not always correspond to increased sensitivity to the locomotor effects of cocaine, suggesting that mechanisms other than dopamine transporter might play a role. Moreover, in adolescent but not adult rats, eating high fat chow increases sensitivity to cocaine and enhances the sensitization that develops to cocaine. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Locomotor adaptability in persons with unilateral transtibial amputation.

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Darter, Benjamin J; Bastian, Amy J; Wolf, Erik J; Husson, Elizabeth M; Labrecque, Bethany A; Hendershot, Brad D

2017-01-01

Locomotor adaptation enables walkers to modify strategies when faced with challenging walking conditions. While a variety of neurological injuries can impair locomotor adaptability, the effect of a lower extremity amputation on adaptability is poorly understood. Determine if locomotor adaptability is impaired in persons with unilateral transtibial amputation (TTA). The locomotor adaptability of 10 persons with a TTA and 8 persons without an amputation was tested while walking on a split-belt treadmill with the parallel belts running at the same (tied) or different (split) speeds. In the split condition, participants walked for 15 minutes with the respective belts moving at 0.5 m/s and 1.5 m/s. Temporal spatial symmetry measures were used to evaluate reactive accommodations to the perturbation, and the adaptive/de-adaptive response. Persons with TTA and the reference group of persons without amputation both demonstrated highly symmetric walking at baseline. During the split adaptation and tied post-adaptation walking both groups responded with the expected reactive accommodations. Likewise, adaptive and de-adaptive responses were observed. The magnitude and rate of change in the adaptive and de-adaptive responses were similar for persons with TTA and those without an amputation. Furthermore, adaptability was no different based on belt assignment for the prosthetic limb during split adaptation walking. Reactive changes and locomotor adaptation in response to a challenging and novel walking condition were similar in persons with TTA to those without an amputation. Results suggest persons with TTA have the capacity to modify locomotor strategies to meet the demands of most walking conditions despite challenges imposed by an amputation and use of a prosthetic limb.

Reliability review of the remote tool delivery system locomotor

Energy Technology Data Exchange (ETDEWEB)

Chesser, J.B.

1999-04-01

The locomotor being built by RedZone Robotics is designed to serve as a remote tool delivery (RID) system for waste retrieval, tank cleaning, viewing, and inspection inside the high-level waste tanks 8D-1 and 8D-2 at West Valley Nuclear Services (WVNS). The RTD systm is to be deployed through a tank riser. The locomotor portion of the RTD system is designed to be inserted into the tank and is to be capable of moving around the tank by supporting itself and moving on the tank internal structural columns. The locomotor will serve as a mounting platform for a dexterous manipulator arm. The complete RTD system consists of the locomotor, dexterous manipulator arm, cameras, lights, cables, hoses, cable/hose management system, power supply, and operator control station.

Results of clinical and radiologic mass-screening tests of the locomotor system of miners in Hungary

Energy Technology Data Exchange (ETDEWEB)

Bene, E.; Temesvary, P.; Szilagyi, M.; Pera, F.

Clinical and radiological screening tests on the locomotor system of 250 workers being active in mines were accomplished by the authors. The test results of 125 miners working underground were compared with those of a control group consisting of equally 125 workers of the same age category, but engaged in open mining. As a result of the investigation it could be stated that miners working in underground mines were affected by diseases of the organs of motion at a very early stage, and in a greater proportion. The most serious deformations were observed with development irregularities and development variations. The development of degenerative locomotor diseases is promoted in Hungary by the working conditions prevailing underground. The completion of the examination procedure of fitness for work by clinical and radiological examinations of the locomotor system is important and highly recommended. The investigation carried out by the authors may serve as a model for the screening tests to be made on the locomotor system of industrial workers.

Characterization of circadian behavior in the starlet sea anemone, Nematostella vectensis.

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William D Hendricks

Full Text Available Although much is known about how circadian systems control daily cycles in the physiology and behavior of Drosophila and several vertebrate models, marine invertebrates have often been overlooked in circadian rhythms research. This study focuses on the starlet sea anemone, Nematostella vectensis, a species that has received increasing attention within the scientific community for its potential as a model research organism. The recently sequenced genome of N. vectensis makes it an especially attractive model for exploring the molecular evolution of circadian behavior. Critical behavioral data needed to correlate gene expression patterns to specific behaviors are currently lacking in N. vectensis.To detect the presence of behavioral oscillations in N. vectensis, locomotor activity was evaluated using an automated system in an environmentally controlled chamber. Animals exposed to a 24 hr photoperiod (12 hr light: 12 hr dark exhibited locomotor behavior that was both rhythmic and predominantly nocturnal. The activity peak occurred in the early half of the night with a 2-fold increase in locomotion. Upon transfer to constant lighting conditions (constant light or constant dark, an approximately 24 hr rhythm persisted in most animals, suggesting that the rhythm is controlled by an endogenous circadian mechanism. Fourier analysis revealed the presence of multiple peaks in some animals suggesting additional rhythmic components could be present. In particular, an approximately 12 hr oscillation was often observed. The nocturnal increase in generalized locomotion corresponded to a 24 hr oscillation in animal elongation.These data confirm the presence of a light-entrainable circadian clock in Nematostella vectensis. Additional components observed in some individuals indicate that an endogenous clock of approximately 12 hr frequency may also be present. By describing rhythmic locomotor behavior in N. vectensis, we have made important progress in developing

Oviposition Behaviors in Relation to Rotation Resistance in the Western Corn Rootworm

NARCIS (Netherlands)

Knolhoff, L.M.; Glas, J.J.; Spencer, J.L.; Berenbaum, M.R.

2010-01-01

Across a large area of the midwestern United States Corn Belt, the western corn rootworm beetle (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) exhibits behavioral resistance to annual crop rotation. Resistant females exhibit increased locomotor activity and frequently lay eggs

The Nicotine-Evoked Locomotor Response: A Behavioral Paradigm for Toxicity Screening in Zebrafish (Danio rerio Embryos and Eleutheroembryos Exposed to Methylmercury.

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Francisco X Mora-Zamorano

Full Text Available This study is an adaptation of the nicotine-evoked locomotor response (NLR assay, which was originally utilized for phenotype-based neurotoxicity screening in zebrafish embryos. Zebrafish embryos do not exhibit spontaneous swimming until roughly 4 days post-fertilization (dpf, however, a robust swimming response can be induced as early as 36 hours post-fertilization (hpf by means of acute nicotine exposure (30-240μM. Here, the NLR was tested as a tool for early detection of locomotor phenotypes in 36, 48 and 72 hpf mutant zebrafish embryos of the non-touch-responsive maco strain; this assay successfully discriminated mutant embryos from their non-mutant siblings. Then, methylmercury (MeHg was used as a proof-of-concept neurotoxicant to test the effectiveness of the NLR assay as a screening tool in toxicology. The locomotor effects of MeHg were evaluated in 6 dpf wild type eleutheroembryos exposed to waterborne MeHg (0, 0.01, 0.03 and 0.1μM. Afterwards, the NLR assay was tested in 48 hpf embryos subjected to the same MeHg exposure regimes. Embryos exposed to 0.01 and 0.03μM of MeHg exhibited significant increases in locomotion in both scenarios. These findings suggest that similar locomotor phenotypes observed in free swimming fish can be detected as early as 48 hpf, when locomotion is induced with nicotine.

Regulation of feeding behavior and psychomotor activity by corticotropin-releasing hormone (CRH in fish

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Kouhei eMatsuda

2013-05-01

Full Text Available Corticotropin-releasing hormone (CRH is a hypothalamic neuropeptide belonging to a family of neuropeptides that includes urocortins, urotensin I and sauvagine in vertebrates. CRH and urocortin act as anorexigenic factors for satiety regulation in fish. In a goldfish model, intracerebroventricular (ICV administration of CRH has been shown to affect not only food intake, but also locomotor and psychomotor activities. In particular, CRH elicits anxiety-like behavior as an anxiogenic neuropeptide in goldfish, as is the case in rodents. This paper reviews current knowledge of CRH and its related peptides derived from studies of teleost fish, as representative non-mammals, focusing particularly on the role of the CRH system, and examines its significance from a comparative viewpoint.

Prenatal Stress and Acute Stress Later in Life Impacts the Responses in Tests for Depressive-Like Behavior in a Sex-Specific Manner

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Sickmann, Helle Mark; Skoven, Christian; Arentzen, Tina S.

in locomotor activity, depressive- and anxiety-like behavior as well as sleep architecture. Some animals were analyzed for CNS microstructural changes based on diffusion MRI. Subsets of PS and control rats were exposed to an acute stressor prior to the behavioral tests. Rearing/climbing activity in a familiar...

Activation of D2 autoreceptors alters cocaine-induced locomotion and slows down local field oscillations in the rat ventral tegmental area.

Science.gov (United States)

Koulchitsky, Stanislav; Delairesse, Charlotte; Beeken, Thom; Monteforte, Alexandre; Dethier, Julie; Quertemont, Etienne; Findeisen, Rolf; Bullinger, Eric; Seutin, Vincent

2016-09-01

Psychoactive substances affecting the dopaminergic system induce locomotor activation and, in high doses, stereotypies. Network mechanisms underlying the shift from an active goal-directed behavior to a "seemingly purposeless" stereotypic locomotion remain unclear. In the present study we sought to determine the relationships between the behavioral effects of dopaminergic drugs and their effects on local field potentials (LFPs), which were telemetrically recorded within the ventral tegmental area (VTA) of freely moving rats. We used the D2/D3 agonist quinpirole in a low, autoreceptor-selective (0.1 mg/kg, i.p.) and in a high (0.5 mg/kg, i.p.) dose, and a moderate dose of cocaine (10 mg/kg, i.p.). In the control group, power spectrum analysis revealed a prominent peak of LFP power in the theta frequency range during active exploration. Cocaine alone stimulated locomotion, but had no significant effect on the peak of the LFP power. In contrast, co-administration of low dose quinpirole with cocaine markedly altered the pattern of locomotion, from goal-directed exploratory behavior to recurrent motion resembling locomotor stereotypy. This behavioral effect was accompanied by a shift of the dominant theta power toward a significantly lower (by ∼15%) frequency. High dose quinpirole also provoked an increased locomotor activity with signs of behavioral stereotypies, and also induced a shift of the dominant oscillation frequency toward the lower range. These results demonstrate a correlation between the LFP oscillation frequency within the VTA and a qualitative aspect of locomotor behavior, perhaps due to a variable level of coherence of this region with its input or output areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Locomotor activity and catecholamine receptor binding in adult normotensive and spontaneously hypertensive rats

International Nuclear Information System (INIS)

Hellstrand, K.; Engel, J.

1980-01-01

The binding of 3 H-WB 4101, an α 1 -adrenoceptor antagonist, the membranes of the cerebral cortex, the hypothalamus, and the lower brainstem was examined in adult spontaneously hypertensive (SH) rats and in normotensive Wistar Kyoto (WK) controls. The specific binding of 3 H-WB 4101 (0.33 nM) was significantly higher in homogenates from the cerebral cortex of SH rats as compared to WK rats. No differences were detected between SH and WK rats in the specific binding of 3 H-spiroperidol (0.25 nM), a dopamine receptor antagonist, to membranes from the corpus striatum and the limbic forebrain. The locomotor activity was significantly higher in SH rats as compared to WK controls, in all probability due to a lack of habituation to environmental change. It is suggested that the high reactivity of SH rats is related to a disfunction in the noradrenergic neurons in the central nervous system. (author)

Immature spinal locomotor output in children with Cerebral Palsy

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Germana Cappellini

2016-10-01

Full Text Available Detailed descriptions of gait impairments have been reported in cerebral palsy (CP, but it is still unclear how maturation of the spinal motoneuron output is affected. Spatiotemporal alpha-motoneuron activation during walking can be assessed by mapping the electromyographic activity profiles from several, simultaneously recorded muscles onto the anatomical rostrocaudal location of the motoneuron pools in the spinal cord, and by means of factor analysis of the muscle activity profiles. Here, we analysed gait kinematics and EMG activity of 11 pairs of bilateral muscles with lumbosacral innervation in 35 children with CP (19 diplegic, 16 hemiplegic, 2-12 years and 33 typically developing (TD children (1-12 years. TD children showed a progressive reduction of EMG burst durations and a gradual reorganization of the spatiotemporal motoneuron output with increasing age. By contrast, children with CP showed very limited age-related changes of EMG durations and motoneuron output, as well as of limb intersegmental coordination and foot trajectory control (on both sides for diplegic children and the affected side for hemiplegic children. Factorization of the EMG signals revealed a comparable structure of the motor output in children with CP and TD children, but significantly wider temporal activation patterns in children with CP, resembling the patterns of much younger TD infants. A similar picture emerged when considering the spatiotemporal maps of alpha-motoneuron activation. Overall, the results are consistent with the idea that early injuries to developing motor regions of the brain substantially affect the maturation of the spinal locomotor output and consequently the future locomotor behaviour.

Investigations into the locomotor activity of white rats under the effect of 50 Hz high voltage fields

Energy Technology Data Exchange (ETDEWEB)

Hilmer, H.; Tembrock, G.

1970-07-01

Tests were carried out on white rats to determine the effect of high-voltage 50 Hz ac electric fields on their locomotor activity. Short-term tests showed that, when they were able to choose between a box not subjected to a field (or subjected to a light field) and one exposed to the field, they stayed for only 27% of the time in the "field box". In the long-term tests, when exposed to the field for three hours, the principal activity peak which occurred during the last hour of the test period was shifted by one hour. Exposure to the field resulted in a change in the ratio between activity during darkness and that during periods of light. It seems probable that this ratio, as well as the daily activity pattern, will be subject to certain afer-effects of an exposure to the field lasting several weeks. 13 refs., 2 figs.

The changes in drug binding activity of GABA receptor and animal neural-behavior after gamma irradiation

International Nuclear Information System (INIS)

Zheng Hui; Zhen Rong; Zhao Naikun; Xue Hong; Wang Zihui

2004-01-01

Objective: The purpose of this study was to investigate the effect of irradiation on gamma-aminobutyric-acid receptor (GABA-R) as well as behavioral changes after brain 60 Co γ-irradiation. Methods: The mice were irradiated with gamma rays (20 Gy; 10 Gy and 5 Gy) . The drug binding activity of GABA receptor in brain receptor was measured by fluorescence anisotropy (FA) and equilibrium dissociation constants. The behavioral changes were observed by the locomotor activity test, elevated plus-maze test and hole-board test at 1, 10, 24 and 48 hr after irradiation. Results: 1. The drug binding activity of the GABA receptor was decreased and the equilibrium dissociation constant (K d ) was significantly increased compared with the negative control group 2 hr after irradiation, and a spike value appeared at 24 hr. It showed that the irradiation might damage or decrease the binding activity and the bio-activity of GABA receptor. 2. The animal experiment confirmed that the irradiated animal model showed neural-behavioral changes of anxiety or depression. 3. The decreased binding activity of GABA receptor and changes in behavior of irradiated animal were dependent on radiation intensity. 4. The changes of behavior was similar to the blocked GABA receptor group. It suggests the relationship of radiation and GABA receptor. Conclusion: These results suggest that GABA receptor may be involved in radiation injury. The functional changes of GABA receptor may be an induction factor of behavioral disorder. The article also discussed the effect of anxiety and results obtained from the point of view of GABA receptor system involvement in the changes observed after irradiation. (authors)

Orbital bleeding in rats while under diethylether anaesthesia does not influence telemetrically determined heart rate, body temperature, locomotor and eating activity when compared with anaesthesia alone

NARCIS (Netherlands)

vanHerck, H; DeBoer, SF; Hesp, APM; VanLith, HA; Baumans, [No Value; Beynen, AC; Herck, H. van; Lith, H.A. van

The question addressed was whether orbital bleeding in rats, while under diethylether anaesthesia, affects their locomotor activity, body core temperature, heart rate rhythm and eating pattern. Roman High Avoidance (RHA) and Roman Low Avoidance (RLA) rats were used to enhance generalization of the

Enkephalin and dynorphin neuropeptides are differently correlated with locomotor hypersensitivity and levodopa-induced dyskinesia in parkinsonian rats.

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Sgroi, Stefania; Capper-Loup, Christine; Paganetti, Paolo; Kaelin-Lang, Alain

2016-06-01

The opioidergic neuropeptides dynorphin (DYN) and enkephalin (ENK) and the D1 and D2 dopaminergic receptors (D1R, D2R) are involved in the striatal control of motor and behavioral function. In Parkinson's disease, motor disturbances such as "on-off" motor fluctuations and involuntary movements (dyskinesia) are severe complications that often arise after chronic l-dihydroxyphenylalanine (l-DOPA) treatment. Changes in the striatal expression of preproENK (PPENK), proDYN (PDYN), D1R, and D2R mRNA have been observed in parkinsonian animals treated with l-DOPA. Enhanced opioidergic transmission has been found in association with l-DOPA-induced dyskinesia, but the connection of PPENK, PDYN, D1R, and D2R mRNA expression with locomotor activity remains unclear. In this study, we measured PPENK, PDYN, D1R and D2R mRNA levels by in situ hybridization in the striatum of 6-OHDA hemi-parkinsonian rats treated with l-DOPA (PD+l-DOPA group), along with two control groups (PD+saline and naive+l-DOPA). We found different levels of expression of PPENK, PDYN, D1R and D2R mRNA across the experimental groups and correlated the changes in mRNA expression with dyskinesia and locomotor variables assessed by open field test during several phases of l-DOPA treatment. Both PDYN and PPENK mRNA levels were correlated with the severity of dyskinesia, while PPENK mRNA levels were also correlated with the frequency of contralateral rotational movements and with locomotor variables. Moreover, a strong correlation was found between D1R mRNA expression and D2R mRNA expression in the PD+l-DOPA group. These findings suggest that, in parkinsonian animals treated with l-DOPA, high levels of PPENK are a prerequisite for a locomotor sensitization to l-DOPA treatment, while PDYN overexpression is responsible only for the development of dyskinesia. Copyright © 2016 Elsevier Inc. All rights reserved.

Locomotor training improves premotoneuronal control after chronic spinal cord injury.

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Knikou, Maria; Mummidisetty, Chaithanya K

2014-06-01

Spinal inhibition is significantly reduced after spinal cord injury (SCI) in humans. In this work, we examined if locomotor training can improve spinal inhibition exerted at a presynaptic level. Sixteen people with chronic SCI received an average of 45 training sessions, 5 days/wk, 1 h/day. The soleus H-reflex depression in response to low-frequency stimulation, presynaptic inhibition of soleus Ia afferent terminals following stimulation of the common peroneal nerve, and bilateral EMG recovery patterns were assessed before and after locomotor training. The soleus H reflexes evoked at 1.0, 0.33, 0.20, 0.14, and 0.11 Hz were normalized to the H reflex evoked at 0.09 Hz. Conditioned H reflexes were normalized to the associated unconditioned H reflex evoked with subjects seated, while during stepping both H reflexes were normalized to the maximal M wave evoked after the test H reflex at each bin of the step cycle. Locomotor training potentiated homosynaptic depression in all participants regardless the type of the SCI. Presynaptic facilitation of soleus Ia afferents remained unaltered in motor complete SCI patients. In motor incomplete SCIs, locomotor training either reduced presynaptic facilitation or replaced presynaptic facilitation with presynaptic inhibition at rest. During stepping, presynaptic inhibition was modulated in a phase-dependent manner. Locomotor training changed the amplitude of locomotor EMG excitability, promoted intralimb and interlimb coordination, and altered cocontraction between knee and ankle antagonistic muscles differently in the more impaired leg compared with the less impaired leg. The results provide strong evidence that locomotor training improves premotoneuronal control after SCI in humans at rest and during walking. Copyright © 2014 the American Physiological Society.

Automated touch screen device for recording complex rodent behaviors

Science.gov (United States)

Mabrouk, O.S.; Dripps, I.J.; Ramani, S.; Chang, C.; Han, J.L.; Rice, KC; Jutkiewicz, E.M.

2016-01-01

Background Monitoring mouse behavior is a critical step in the development of modern pharmacotherapies. New Method Here we describe the application of a novel method that utilizes a touch display computer (tablet) and software to detect, record, and report fine motor behaviors. A consumer-grade tablet device is placed in the bottom of a specially made acrylic cage allowing the animal to walk on the device (MouseTrapp). We describe its application in open field (for general locomotor studies) which measures step lengths and velocity. The device can perform light-dark (anxiety) tests by illuminating half of the screen and keeping the other half darkened. A divider is built into the lid of the device allowing the animal free access to either side. Results Treating mice with amphetamine and the delta opioid peptide receptor agonist SNC80 stimulated locomotor activity on the device. Amphetamine increased step velocity but not step length during its peak effect (40–70 min after treatment), thus indicating detection of subtle amphetamine-induced effects. Animals showed a preference (74% of time spent) for the darkened half compared to the illuminated side. Comparison with Existing Method Animals were videotaped within the chamber to compare quadrant crosses to detected motion on the device. The slope, duration and magnitude of quadrant crosses tightly correlated with overall locomotor activity as detected by Mousetrapp. Conclusions We suggest that modern touch display devices such as MouseTrapp will be an important step toward automation of behavioral analyses for characterizing phenotypes and drug effects. PMID:24952323

The number of postsynaptic currents necessary to produce locomotor- related cyclic information in neurons in the neonatal rat spinal cord

DEFF Research Database (Denmark)

Raastad, Morten; Johnson, Bruce R.; Kiehn, Ole

1996-01-01

To understand better how synaptic signaling contributes to network activity, we analyzed the potential contribution of putative unitary postsynaptic currents (PSCs) to locomotor-related information received by spinal interneurons in neonatal rats. The average cyclic modulation of the whole-cell c......-5) of the synapses contributing to the cyclic information need to be active simultaneously. This suggests that individual presynaptic cells in a central locomotor network can have a powerful influence on other neurons....

Behavioral and hormonal changes associated with the infective dose in experimental taeniasis in golden hamsters (Mesocricetus auratus).

Science.gov (United States)

Domínguez-Roldan, Rosa; Hallal-Calleros, Claudia; Sciutto, Edda; Hernández, Marisela; Aguirre-Flores, Virginio; García-Jiménez, Sara; Báez-Saldaña, Armida; Flores-Pérez, Fernando Iván

2016-07-01

It has been reported that behavioral changes relate to infection in different parasitoses. However, the relation between the extent of the behavioral changes and the magnitude of the infection has been scarcely studied. The aim of this study was to evaluate the relationship between different doses of infection and the behavioral changes induced in the experimental Taenia pisiformis taeniasis in golden hamsters. Groups of nine hamsters were infected with three or six T. pisiformis metacestodes. The locomotor activity was quantified daily in an open field test during the 21 days after infection; anxiety test was performed in an elevated plus-maze with a dark/light area at 7, 14 and 21 days post-infection, and serum cortisol levels were determined by radioimmunoassay before infection and at day 22 after infection. The challenge itself induced modifications on behavior and cortisol levels in hamsters, with or without successful infection (taenia development). Animals challenged with three metacestodes induced a decrease in locomotor activity and an increase in anxiety in infected animals. A higher and earlier decrease in locomotor activity and increased anxiety levels were observed in hamsters challenged with six cysticerci, which were accompanied by higher levels of sera cortisol at the end of the experiment. At necropsy, 44-55% of hamster became infected with an efficiency of implantation of 22-26%, challenged with three or six cysticerci respectively. The challenge of hamsters with metacestodes, promote behavioral changes in an extent dependent on the magnitude of the challenge, disregarding the effectiveness of the infection. Copyright © 2016 Elsevier Inc. All rights reserved.

Contribution of nucleus accumbens core (AcbC to behavior control during a learned resting period: introduction of a novel task and lesion experiments.

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Chika Sato

Full Text Available In recent years, the study of resting state neural activity has received much attention. To better understand the roles of different brain regions in the regulation of behavioral activity in an arousing or a resting period, we developed a novel behavioral paradigm (8-arm food-foraging task; 8-arm FFT using the radial 8-arm maze and examined how AcbC lesions affect behavioral execution and learning. Repetitive training on the 8-arm FFT facilitated motivation of normal rats to run quickly to the arm tips and to the center platform before the last-reward collection. Importantly, just after this point and before confirmation of no reward at the next arm traverse, locomotor activity decreased. This indicates that well-trained rats can predict the absence of the reward at the end of food seeking and then start another behavior, namely planned resting. Lesions of the AcbC after training selectively impaired this reduction of locomotor activity after the last-reward collection without changing activity levels before the last-reward collection. Analysis of arm-selection patterns in the lesioned animals suggests little influence of the lesion in the ability to predict the reward absence. AcbC lesions did not change exploratory locomotor activity in an open-field test in which there were no rewards. This suggests that the AcbC controls the activity level of planned resting behavior shaped by the 8-arm FFT. Rats receiving training after AcbC lesioning showed a reduction in motivation for reward seeking. Thus, the AcbC also plays important roles not only in controlling the activity level after the last-reward collection but also in motivational learning for setting the activity level of reward-seeking behavior.

Differential effects of antipsychotic and propsychotic drugs on prepulse inhibition and locomotor activity in Roman high- (RHA) and low-avoidance (RLA) rats

DEFF Research Database (Denmark)

Oliveras, Ignasi; Sánchez-González, Ana; Sampedro-Viana, Daniel

2017-01-01

acutely administered propsychotic (DOI, MK-801) and antipsychotic drugs (haloperidol, clozapine), as well as apomorphine, on prepulse inhibition (PPI) of startle and locomotor activity (activity cages). RESULTS: RHA-I rats display a consistent deficit of PPI compared with RLA-I rats. The typical...... antipsychotic haloperidol (dopamine D2 receptor antagonist) reversed the PPI deficit characteristic of RHA-I rats (in particular at 65 and 70 dB prepulse intensities) and reduced locomotion in both strains. The atypical antipsychotic clozapine (serotonin/dopamine receptor antagonist) did not affect PPI...

Footwear and locomotor skill performance in preschoolers.

Science.gov (United States)

Robinson, Leah E; Rudisill, Mary E; Weimar, Wendi H; Breslin, Casey M; Shroyer, Justin F; Morera, Maria

2011-10-01

The effect of footwear on locomotor skill performance was examined. 12 children (4 boys, 8 girls; M age = 56.3 mo., SD = 3.3) served as participants. Participants were randomly assigned to perform the locomotor subscale of Ulrich's Test of Gross Motor Development in two shoe conditions (Condition 1: Stride Rite athletic shoes, and Condition 2: flip flop sandals). Children scored significantly higher when wearing athletic shoes than flip-flop sandals. This finding is relevant for motor performance and safety in physical education and movement programs.

Dissociation in effects of lesions of the nucleus accumbens core and shell on appetitive pavlovian approach behavior and the potentiation of conditioned reinforcement and locomotor activity by D-amphetamine.

Science.gov (United States)

Parkinson, J A; Olmstead, M C; Burns, L H; Robbins, T W; Everitt, B J

1999-03-15

Dopamine release within the nucleus accumbens (NAcc) has been associated with both the rewarding and locomotor-stimulant effects of abused drugs. The functions of the NAcc core and shell were investigated in mediating amphetamine-potentiated conditioned reinforcement and locomotion. Rats were initially trained to associate a neutral stimulus (Pavlovian CS) with food reinforcement (US). After excitotoxic lesions that selectively destroyed either the NAcc core or shell, animals underwent additional CS-US training sessions and then were tested for the acquisition of a new instrumental response that produced the CS acting as a conditioned reinforcer (CR). Animals were infused intra-NAcc with D-amphetamine (0, 1, 3, 10, or 20 microg) before each session. Shell lesions affected neither Pavlovian nor instrumental conditioning but completely abolished the potentiative effect of intra-NAcc amphetamine on responding with CR. Core-lesioned animals were impaired during the Pavlovian retraining sessions but showed no deficit in the acquisition of responding with CR. However, the selectivity in stimulant-induced potentiation of the CR lever was reduced, as intra-NAcc amphetamine infusions dose-dependently increased responding on both the CR lever and a nonreinforced (control) lever. Shell lesions produced hypoactivity and attenuated amphetamine-induced activity. In contrast, core lesions resulted in hyperactivity and enhanced the locomotor-stimulating effect of amphetamine. These results indicate a functional dissociation of subregions of the NAcc; the shell is a critical site for stimulant effects underlying the enhancement of responding with CR and locomotion after intra-NAcc injections of amphetamine, whereas the core is implicated in mechanisms underlying the expression of CS-US associations.

Paraquat affects mitochondrial bioenergetics, dopamine system expression, and locomotor activity in zebrafish (Danio rerio).

Science.gov (United States)

Wang, Xiao H; Souders, Christopher L; Zhao, Yuan H; Martyniuk, Christopher J

2018-01-01

The dipyridyl herbicide paraquat induces oxidative stress in cells and is implicated in adult neurodegenerative diseases. However, less is known about paraquat toxicity in early stages of vertebrate development. To address this gap, zebrafish (Danio rerio) embryos were exposed to 1, 10 and 100 μM paraquat for 96 h. Paraquat did not induce significant mortality nor deformity in embryos and larvae, but it did accelerate time to hatch. To evaluate whether mitochondrial respiration was related to earlier hatch times, oxygen consumption rate was measured in whole embryos. Maximal respiration of embryos exposed to 100 μM paraquat for 24 h was reduced by more than 70%, suggesting that paraquat negatively impacts mitochondrial bioenergetics in early development. Based upon this evidence for mitochondrial dysfunction, transcriptional responses of oxidative stress- and apoptosis-related genes were measured. Fish exposed to 1 μM paraquat showed higher expression levels of superoxide dismutase 2, heat shock protein 70, Bcl-2-associated X protein, and B-cell CLL/lymphoma 2a compared to control fish. No differences among groups were detected in larvae exposed to 10 and 100 μM paraquat, suggesting a non-monotonic response. We also measured endpoints related to larval behavior and dopaminergic signaling as paraquat is associated with degeneration of dopamine neurons. Locomotor activity was stimulated with 100 μM paraquat and dopamine transporter and dopamine receptor 3 mRNA levels were increased in larvae exposed to 1 μM paraquat, interpreted to be a compensatory response at lower concentrations. This study improves mechanistic understanding into the toxic actions of paraquat on early developmental stages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of the lipid regulator drug gemfibrozil: A toxicological and behavioral perspective.

Science.gov (United States)

Henriques, Jorge F; Almeida, Ana Rita; Andrade, Thayres; Koba, Olga; Golovko, Oksana; Soares, Amadeu M V M; Oliveira, Miguel; Domingues, Inês

2016-01-01

Pharmaceuticals are emerging contaminants as their worldwide consumption increases. Fibrates such as gemfibrozil (GEM) are used in human medicine to reduce blood concentrations of cholesterol and triacylglycerol and also are some of the most frequently reported pharmaceuticals in waste waters and surface waters. Despite some studies have already demonstrated the negative impact in physiological and/or reproductive endpoints in adult fish, data on survival and behavioral effects in fish larvae are lacking. This study aimed to assess the effects of GEM on zebrafish eleutheroembryo development and locomotor behavior. A fish embryo toxicity (FET) test was undertaken to evaluate GEM acute toxicity by exposing embryos to 0, 6.58, 9.87, 14.81, 22.22, 33.33 and 50mg/L. Developmental endpoints such as hatching success, edemas and malformations were recorded. A second test was undertaken by exposing embryos to 0, 1.5, 3 and 6mg/L in order to evaluate the effects of GEM on 120 and 144h post fertilization (hpf) larvae locomotor activity by video tracking, using a Zebrabox(®) (Viewpoint, France) device. From the data recorded, several parameters such as total swimming distance (TSD) and total swimming time (TST) in each 120s integration time were calculated. Data showed that this compound has a moderate toxic effect on fish embryo development, affecting both survival and hatching success with a calculated 96h LC50 of 11.01mg/L and no effects at the developmental level at 6mg/L. GEM seems to impair locomotor activity, even at concentrations where developmental abnormalities were unperceived, at concentrations as low as 1.5mg/L. Both TSD and TST were sensitive to GEM exposure. These effects do not seem to be independent of the developmental stage as 120hpf larvae seem to present a development bias with repercussions in locomotor behavior. This study highlights the need to include behavioral endpoints in ecotoxicological assays as this seems to be a more sensitive endpoint often

Effects of gender on locomotor sensitivity to amphetamine, body weight, and fat mass in regulator of G protein signaling 9 (RGS9) knockout mice.

Science.gov (United States)

Walker, Paul D; Jarosz, Patricia A; Bouhamdan, Mohamad; MacKenzie, Robert G

2015-01-01

Regulator of G-protein signaling (RGS) protein 9-2 is enriched in the striatum where it modulates dopamine and opioid receptor-mediated signaling. RGS9 knockout (KO) mice show increased psychostimulant-induced behavioral sensitization, as well as exhibit higher body weights and greater fat accumulation compared to wild-type (WT) littermates. In the present study, we found gender influences on each of these phenotypic characteristics. Female RGS9 KO mice exhibited greater locomotor sensitization to amphetamine (1.0mg/kg) treatment as compared to male RGS9 KO mice. Male RGS9 KO mice showed increased body weights as compared to male WT littermates, while no such differences were detected in female mice. Quantitative magnetic resonance showed that male RGS9 KO mice accumulated greater fat mass vs. WT littermates at 5months of age. Such observations could not be explained by increased caloric consumption since male and female RGS9 KO mice demonstrated equivalent daily food intake as compared to their respective WT littermates. Although indirect calorimetry methods found decreased oxygen consumption and carbon dioxide production during the 12-hour dark phase in male RGS9 KO vs. WT mice which are indicative of less energy expenditure, male RGS9 KO mice exhibited lower levels of locomotor activity during this period. Genotype had no effect on metabolic activities when KO and WT groups were compared under fasting vs. feeding treatments. In summary, these results highlight the importance of factoring gender into the experimental design since many studies conducted in RGS9 KO mice utilize locomotor activity as a measured outcome. Copyright © 2014. Published by Elsevier Inc.

A semiautomated test apparatus for studying partner preference behavior in the rat

NARCIS (Netherlands)

J. Bakker (Julie); J. van Ophemert (J.); F. Eijskoot (F.); A.K. Slob (Koos)

1994-01-01

textabstractA semiautomated three-compartment box (3CB) for studying partner preference behavior of rats is decribed. This apparatus automatically records the rat's time spent in each compartment, as well as the locomotor activity (i.e., the number of visits an animal pays to each compartment).

Locomotor activity of rats with SCI is improved by dexmedetomidine by targeting the expression of inflammatory factors.

Science.gov (United States)

Wang, Wei-Guo; Wang, Lin; Jiao, Zhen-Hua; Xue, Bin; Xu, Zhan-Wang

2018-04-26

Dexmedetomidine, a well‑known selective α‑2 adrenoceptor agonist, inhibits the apoptosis of neurons and protects other organs from oxidative damage. In the present study, the effect of dexmedetomidine on spinal cord injury (SCI) in a rat model was investigated. The SCI rat model was prepared using the weight‑drop method, and the effect of dexmedetomidine on locomotor activity was analyzed using the Basso, Beattie and Bresnahan (BBB) rating scale. Western blot analysis was used to observe changes in the expression of apoptosis‑related proteins, including B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X protein (Bax). The results revealed that treatment of the SCI rats with dexmedetomidine at a dose of 50 mg/kg significantly prevented the formation of edema in the tissues of the spinal cord. Dexmedetomidine also inhibited the SCI‑induced accumulation of neutrophils in the spinal cord. The BBB scores were significantly increased (PSCI treated with dexmedetomidine after 10 days. The results of grid walking test revealed a marked decrease in the number of missteps following 10 days of dexmedetomidine treatment. The expression levels of tumor necrosis factor (TNF)‑α and interleukin (IL)‑1β were significantly reduced (PSCI exerted an inhibitory effect on the SCI‑induced increase in the expression of Bax. The expression of Bcl‑2 was increased in the dexmedetomidine treated rats, compared with that in the control group. Taken together, dexmedetomidine improved the locomotor activity of the rats through the inhibition of edema, reduction in the expression levels of TNF‑α and IL‑1β, and inhibition of the induction of apoptosis. Therefore, dexmedetomidine may be of therapeutic importance for patients with SCI.

Dentate gyrus neurogenesis ablation via cranial irradiation enhances morphine self-administration and locomotor sensitization.

Science.gov (United States)

Bulin, Sarah E; Mendoza, Matthew L; Richardson, Devon R; Song, Kwang H; Solberg, Timothy D; Yun, Sanghee; Eisch, Amelia J

2018-03-01

Adult dentate gyrus (DG) neurogenesis is important for hippocampal-dependent learning and memory, but the role of new neurons in addiction-relevant learning and memory is unclear. To test the hypothesis that neurogenesis is involved in the vulnerability to morphine addiction, we ablated adult DG neurogenesis and examined morphine self-administration (MSA) and locomotor sensitization. Male Sprague-Dawley rats underwent hippocampal-focused, image-guided X-ray irradiation (IRR) to eliminate new DG neurons or sham treatment (Sham). Six weeks later, rats underwent either MSA (Sham = 16, IRR = 15) or locomotor sensitization (Sham = 12, IRR = 12). Over 21 days of MSA, IRR rats self-administered ~70 percent more morphine than Sham rats. After 28 days of withdrawal, IRR rats pressed the active lever 40 percent more than Sham during extinction. This was not a general enhancement of learning or locomotion, as IRR and Sham groups had similar operant learning and inactive lever presses. For locomotor sensitization, both IRR and Sham rats sensitized, but IRR rats sensitized faster and to a greater extent. Furthermore, dose-response revealed that IRR rats were more sensitive at a lower dose. Importantly, these increases in locomotor activity were not apparent after acute morphine administration and were not a byproduct of irradiation or post-irradiation recovery time. Therefore, these data, along with other previously published data, indicate that reduced hippocampal neurogenesis confers vulnerability for multiple classes of drugs. Thus, therapeutics to specifically increase or stabilize hippocampal neurogenesis could aid in preventing initial addiction as well as future relapse. © 2017 Society for the Study of Addiction.

Spinal cord injury: overview of experimental approaches used to restore locomotor activity.

Science.gov (United States)

Fakhoury, Marc

2015-01-01

Spinal cord injury affects more than 2.5 million people worldwide and can lead to paraplegia and quadriplegia. Anatomical discontinuity in the spinal cord results in disruption of the impulse conduction that causes temporary or permanent changes in the cord's normal functions. Although axonal regeneration is limited, damage to the spinal cord is often accompanied by spontaneous plasticity and axon regeneration that help improve sensory and motor skills. The recovery process depends mainly on synaptic plasticity in the preexisting circuits and on the formation of new pathways through collateral sprouting into neighboring denervated territories. However, spontaneous recovery after spinal cord injury can go on for several years, and the degree of recovery is very limited. Therefore, the development of new approaches that could accelerate the gain of motor function is of high priority to patients with damaged spinal cord. Although there are no fully restorative treatments for spinal injury, various rehabilitative approaches have been tested in animal models and have reached clinical trials. In this paper, a closer look will be given at the potential therapies that could facilitate axonal regeneration and improve locomotor recovery after injury to the spinal cord. This article highlights the application of several interventions including locomotor training, molecular and cellular treatments, and spinal cord stimulation in the field of rehabilitation research. Studies investigating therapeutic approaches in both animal models and individuals with injured spinal cords will be presented.

Nicotine Modifies Corticostriatal Plasticity and Amphetamine Rewarding Behaviors in Mice123

Science.gov (United States)

Storey, Granville P.; Heimbigner, Lauren; Walwyn, Wendy M.; Bamford, Nigel S.

2016-01-01

Abstract Corticostriatal signaling participates in sensitized responses to drugs of abuse, where short-term increases in dopamine availability provoke persistent, yet reversible, changes in glutamate release. Prior studies in mice show that amphetamine withdrawal promotes a chronic presynaptic depression in glutamate release, whereas an amphetamine challenge reverses this depression by potentiating corticostriatal activity in direct pathway medium spiny neurons. This synaptic plasticity promotes corticostriatal activity and locomotor sensitization through upstream changes in the activity of tonically active cholinergic interneurons (ChIs). We used a model of operant drug-taking behaviors, in which mice self-administered amphetamine through an in-dwelling catheter. Mice acquired amphetamine self-administration under fixed and increasing schedules of reinforcement. Following a period of abstinence, we determined whether nicotinic acetylcholine receptors modified drug-seeking behavior and associated alterations in ChI firing and corticostriatal activity. Mice responding to conditioned reinforcement showed reduced ChI and corticostriatal activity ex vivo, which paradoxically increased following an amphetamine challenge. Nicotine, in a concentration that increases Ca2+ influx and desensitizes α4β2*-type nicotinic receptors, reduced amphetamine-seeking behaviors following abstinence and amphetamine-induced locomotor sensitization. Nicotine blocked the depression of ChI firing and corticostriatal activity and the potentiating response to an amphetamine challenge. Together, these results demonstrate that nicotine reduces reward-associated behaviors following repeated amphetamine and modifies the changes in ChIs firing and corticostriatal activity. By returning glutamatergic activity in amphetamine self-administering mice to a more stable and normalized state, nicotine limits the depression of striatal activity in withdrawal and the increase in activity following

Apomorphine effects on frog locomotor behavior.

Science.gov (United States)

Chu, Joanne; Wilczynski, Walter

2007-05-16

The neuroanatomical pathways of the DA systems have been shown to be largely conserved across many vertebrate taxa. It is less certain whether the structural similarities seen between mammals and amphibians reflect a similar functional homology. DA is well known for its role in facilitating motor behaviors in mammals. We examined whether a similar role for DA exists in amphibians using the Northern Leopard Frog (Rana pipiens). We investigated the effects of the nonspecific DA agonist, apomorphine (APO) on a complex motor task that included two distinct components known to be differentially modulated by DA in mammals: swimming and climbing. We demonstrated that a high single dose of APO (20 mg/kg, body weight) strongly increased the amount of time spent completing the motor task. Furthermore, we showed that although APO did not significantly alter several aspects of swimming behavior, two aspects of climbing behavior were disrupted. Both climbing speed and climbing ability were impaired by APO treatment. These results increase our understanding of DA function in amphibians and add to our understanding of structure-function homologies of dopamine function across vertebrate taxa.

Locomotor problems among rural elderly population in a District of Aligarh, North India.

Science.gov (United States)

Maroof, Mohd; Ahmad, Anees; Khalique, Najam; Ansari, M Athar

2017-01-01

Locomotor functions decline with the age along with other physiological changes. This results in deterioration of the quality of life with decreased social and economic role in the society, as well as increased dependency, for the health care and other basic services. The demographic transition resulting in increased proportion of elderly may pose a burden to the health system. To find the prevalence of locomotor problems among the elderly population, and related sociodemographic factors. The study was a community-based cross-sectional study done at field practice area of Rural Health Training Centre, JN Medical College, AMU, Aligarh, Uttar Pradesh, India. A sample of 225 was drawn from 1018 elderly population aged 60 years and above using systematic random sampling with probability proportionate to size. Sociodemographic characteristics were obtained using pretested and predesigned questionnaire. Locomotor problems were assessed using the criteria used by National Sample Survey Organization. Data were analyzed using SPSS version 20. Chi-square test was used to test relationship of locomotor problems with sociodemographic factors. P locomotor problems among the elderly population was 25.8%. Locomotor problems were significantly associated with age, gender, and working status whereas no significant association with literacy status and marital status was observed. The study concluded that approximately one-fourth of the elderly population suffered from locomotor problems. The sociodemographic factors related to locomotor problems needs to be addressed properly to help them lead an independent and economically productive life.

A disparity between locomotor economy and territory-holding ability in male house mice.

Science.gov (United States)

Morris, Jeremy S; Ruff, James S; Potts, Wayne K; Carrier, David R

2017-07-15

Both economical locomotion and physical fighting are important performance traits to many species because of their direct influence on components of Darwinian fitness. Locomotion represents a substantial portion of the total daily energy budget of many animals. Fighting performance often determines individual reproductive fitness through the means of resource control, social dominance and access to mates. However, phenotypic traits that improve either locomotor economy or fighting ability may diminish performance in the other. Here, we tested for a predicted disparity between locomotor economy and competitive ability in wild-derived house mice ( Mus musculus ). We used 8 week social competition trials in semi-natural enclosures to directly measure male competitive ability through territorial control and female occupancy within territories. We also measured oxygen consumption during locomotion for each mouse using running trials in an enclosed treadmill and open-flow respirometry. Our results show that territory-holding males have higher absolute and mass-specific oxygen consumption when running (i.e. reduced locomotor economy) compared with males that do not control territories. This relationship was present both before and after 8 week competition trials in semi-natural enclosures. This disparity between physical competitive ability and economical locomotion may impose viability costs on males in species for which competition over mates is common and may constrain the evolution of behavioral and phenotypic diversity, particularly in natural settings with environmental and resource variability. © 2017. Published by The Company of Biologists Ltd.

Testing candidate genes for attention-deficit/hyperactivity disorder in fruit flies using a high throughput assay for complex behavior

DEFF Research Database (Denmark)

Rohde, Palle Duun; Madsen, Lisbeth Strøm; Arvidson, Sandra Marie Neumann

2016-01-01

Fruit flies are important model organisms for functional testing of candidate genes in multiple disciplines, including the study of human diseases. Here we use a high-throughput locomotor activity assay to test the response on activity behavior of gene disruption in Drosophila melanogaster. The aim...

Gender differences in locomotor and stereotypic behavior associated with l-carnitine treatment in mice.

Science.gov (United States)

Benvenga, Salvatore; Itri, Elenora; Hauser, Peter; De Tolla, Louis; Yu, Sui-Foh; Testa, Giuseppe; Pappalardo, Maria Angela; Trimarchi, Francesco; Amato, Antonino

2011-02-01

The carnitines exert neuroprotective and neuromodulatory actions, and carnitine supplementation increases locomotor activity (LMA) in experimental animals. We measured 13 indexes of LMA and 3 indexes of stereotypic activity (STA) in adult male and female caged mice. In a randomized 4-week trial, 10 males and 10 females received 50 mg/kg body weight PO l-carnitine, and another 10 males and 10 females received placebo. Compared with placebo-treated females, placebo-treated males had a greater number of stereotypies (NSTs), stereotypy counts (STCs), stereotypy time (STT), and right front time (RFT), but smaller total distance traveled (TDT), margin distance (MD), number of vertical movements (NVMs), and left rear time (LRT). Compared with placebo-treated males, carnitine-treated males had greater horizontal activity (HA), movement time (MT), NVM, STT, TDT, STC, MD, LRT, and clockwise revolutions (CRs), but smaller left front time (LFT) and RFT. Compared with placebo-treated females, carnitine-treated females had greater NST, STC, STT, LFT, and RFT, but smaller NM, HA, NVM, VA, MT, anticlockwise revolutions (ACRs), CR, TDT, and MD; right rear time (RRT) remained statistically insignificant across all comparisons. In summary, l-carnitine caused gender differences to persist for STC, diminish for NST and STT, disappear for LRT and NVM, change in the opposite direction for TDT and MD, appear de novo for HA, VA, NM, MT, and LFT, and remain absent for RRT and ACR. Some indexes of LMA and STA are sexually dimorphic in adult mice, and l-carnitine differentially maintains, diminishes/cancels, inverts, or creates the sexual dimorphism of particular indexes. Copyright © 2011 Elsevier HS Journals, Inc. All rights reserved.

An Integrated Gait and Balance Analysis System to Define Human Locomotor Control

Science.gov (United States)

2016-04-29

test hypotheses they developed about how people walk. An Integrated Gait and Balance Analysis System to define Human Locomotor Control W911NF-14-R-0009...An Integrated Gait and Balance Analysis System to Define Human Locomotor Control Walking is a complicated task that requires the motor coordination...Gait and Balance Analysis System to Define Human Locomotor Control Report Title Walking is a complicated task that requires the motor coordination across

Anatomía del Aparato Locomotor, 2010-11

OpenAIRE

Juanes Méndez, Juan Antonio

2010-01-01

I. Materiales de clase: 1.Sistema Oseo. Las Articulaciones: definición, clasificaciones; 2.Esqueleto Axial; 3.Esqueleto Apendicular; 4. Organización del sistema nervioso periférico. Inervación del Aparato Locomotor; 5. Sistema muscular. II. Bibliografía y atlas Establecer la correlación morfofuncional del aparato locomotor necesaria para la deducción deficitaria derivada de las alteraciones de la dinámica osteoarticular. Esta asignatura se imparte en el primer curso del Grado en Terapia Oc...

Anxiolytic property of hydro-alcohol extract of Lactuca sativa and its effect on behavioral activities of mice.

Science.gov (United States)

Harsha, Singapura Nagesh; Anilakumar, Kandangath Raghavan

2013-01-01

Lactuca sativa, belonging to the Asteraceae family, is a leafy vegetable known for its medicinal properties. This study aimed to understand the mechanism of Lactuca sativa extract with respect to pharmacological action.We investigated the anxiolytic effects of hydro-alcoholic extract of leaves of Lactuca sativa on mice. The behavioral tests performed on mice models to assess anti-anxiety properties were: open field test (OFT), elevated plus maze test (EPM), elevated T maze test, and marble burying test. Increased locomotor activity and time spent in the "open-arm" were observed in extract fed group. Malondialdehyde (MDA) and nitrite levels were decreased, catalase and glutathione levels were increased in Lactuca sativa treated mice. The data obtained in the present study suggests that the extract of Lactuca sativa can afford significant protection against anxiolytic activity.

Anxiolytics may promote locomotor function recovery in spinal cord injury patients

Directory of Open Access Journals (Sweden)

Pierre A Guertin

2008-09-01

Full Text Available Pierre A GuertinNeuroscience Unit, Laval University Medical Center (CHUL, Quebec City, CanadaAbstract: Recent findings in animal models of paraplegia suggest that specific nonbenzodiazepine anxiolytics may temporarily restore locomotor functions after spinal cord injury (SCI. Experiments using in vitro models have revealed, indeed, that selective serotonin receptor (5-HTR ligands such as 5-HTR1A agonists, known as relatively safe anxiolytics, can acutely elicit episodes of rhythmic neuronal activity refered to as fictive locomotion in isolated spinal cord preparations. Along the same line, in vivo studies have recently shown that this subclass of anxiolytics can induce, shortly after systemic administration (eg, orally or subcutaneously, some locomotor-like hindlimb movements during 45–60 minutes in completely spinal cord-transected (Tx rodents. Using ‘knock-out’ mice (eg, 5-HTR7-/- and selective antagonists, it has been clearly established that both 5-HTR1A and 5-HTR7 were critically involved in mediating the pro-locomotor effects induced by 8-OH-DPAT (typically referred to as a 5-HTR1A agonist in Tx animals. Taken together, these in vitro and in vivo data strongly support the idea that 5-HTR1A agonists may eventually become constitutive elements of a novel first-in-class combinatorial treatment aimed at periodically inducing short episodes of treadmill stepping in SCI patients.Keywords: 5-HT agonists, anxiolytics, locomotion, SCI

Phenotypic characterization of speed-associated gait changes in mice reveals modular organization of locomotor networks

DEFF Research Database (Denmark)

Bellardita, Carmelo; Kiehn, Ole

2015-01-01

behavioral outcomes expressed at different speeds of locomotion. Here, we use detailed kinematic analyses to search for signatures of a modular organization of locomotor circuits in intact and genetically modified mice moving at different speeds of locomotion. We show that wild-type mice display three...... distinct gaits: two alternating, walk and trot, and one synchronous, bound. Each gait is expressed in distinct ranges of speed with phenotypic inter-limb and intra-limb coordination. A fourth gait, gallop, closely resembled bound in most of the locomotor parameters but expressed diverse inter......-limb coordination. Genetic ablation of commissural V0V neurons completely removed the expression of one alternating gait, trot, but left intact walk, gallop, and bound. Ablation of commissural V0V and V0D neurons led to a loss of walk, trot, and gallop, leaving bound as the default gait. Our study provides...

Combined effects of diethylpropion and alcohol on locomotor activity of mice: participation of the dopaminergic and opioid systems

Directory of Open Access Journals (Sweden)

Gevaerd M.S.

1999-01-01

Full Text Available The widespread consumption of anorectics and combined anorectic + alcohol misuse are problems in Brazil. In order to better understand the interactive effects of ethanol (EtOH and diethylpropion (DEP we examined the locomotion-activating effects of these drugs given alone or in combination in mice. We also determined whether this response was affected by dopamine (DA or opioid receptor antagonists. A total of 160 male Swiss mice weighing approximately 30 g were divided into groups of 8 animals per group. The animals were treated daily for 7 consecutive days with combined EtOH + DEP (1.2 g/kg and 5.0 mg/kg, ip, EtOH (1.2 g/kg, ip, DEP (5.0 mg/kg, ip or the control solution coadministered with the DA antagonist haloperidol (HAL, 0.075 mg/kg, ip, the opioid antagonist naloxone (NAL, 1.0 mg/kg, ip, or vehicle. On days 1, 7 and 10 after the injections, mice were assessed in activity cages at different times (15, 30, 45 and 60 min for 5 min. The acute combination of EtOH plus DEP induced a significantly higher increase in locomotor activity (day 1: 369.5 ± 34.41 when compared to either drug alone (day 1: EtOH = 232.5 ± 23.79 and DEP = 276.0 ± 12.85 and to control solution (day 1: 153.12 ± 7.64. However, the repeated administration of EtOH (day 7: 314.63 ± 26.79 and day 10: 257.62 ± 29.91 or DEP (day 7: 309.5 ± 31.65 and day 10: 321.12 ± 39.24 alone or in combination (day 7: 459.75 ± 41.28 and day 10: 427.87 ± 33.0 failed to induce a progressive increase in the locomotor response. These data demonstrate greater locomotion-activating effects of the EtOH + DEP combination, probably involving DA and/or opioid receptor stimulation, since the daily pretreatment with HAL (day 1: EtOH + DEP = 395.62 ± 11.92 and EtOH + DEP + HAL = 371.5 ± 6.76; day 7: EtOH + DEP = 502.5 ± 42.27 and EtOH + DEP + HAL = 281.12 ± 16.08; day 10: EtOH + DEP = 445.75 ± 16.64 and EtOH + DEP + HAL = 376.75 ± 16.4 and NAL (day 1: EtOH + DEP = 553.62 ± 38.15 and Et

Overexpression of cerebral and hepatic cytochrome P450s alters behavioral activity of rat offspring following prenatal exposure to lindane

Energy Technology Data Exchange (ETDEWEB)

Johri, Ashu; Yadav, Sanjay; Dhawan, Alok [Developmental Toxicology Division, Industrial Toxicology Research Centre, P. O. Box 80, M. G. Marg, Lucknow-226 001, U. P. (India); Parmar, Devendra [Developmental Toxicology Division, Industrial Toxicology Research Centre, P. O. Box 80, M. G. Marg, Lucknow-226 001, U. P. (India)

2007-12-15

Oral administration of different doses (0.0625, 0.125 or 0.25 mg/kg corresponding to 1/1400th, 1/700th or 1/350th of LD{sub 50}) of lindane to the pregnant Wistar rats from gestation days 5 to 21 were found to produce a dose-dependent increase in the activity of cytochrome P450 (CYP)-dependent 7-ethoxyresorufin-O-deethylase (EROD), 7-pentoxyresorufin-O-dealkylase (PROD) and N-nitrosodimethylamine demethylase (NDMA-d) in brain and liver of offspring postnatally at 3 weeks. The increase in the activity of CYP monooxygenases was found to be associated with the increase in the mRNA and protein expression of xenobiotic metabolizing CYP1A, 2B and 2E1 isoenzymes in the brain and liver of offspring. Dose-dependent alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 3 weeks have suggested that increase in CYP activity may possibly lead to the formation of metabolites to the levels that may be sufficient to alter the behavioral activity of the offspring. Interestingly, the inductive effect on cerebral and hepatic CYPs was found to persist postnatally up to 6 weeks in the offspring at the relatively higher doses (0.125 and 0.25 mg/kg) of lindane and up to 9 weeks at the highest dose (0.25 mg/kg), though the magnitude of induction was less than that observed at 3 weeks. Alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 6 and 9 weeks, though significant only in the offspring at 3 and 6-week of age, have further indicated that due to the reduced activity of the CYPs during the ontogeny, lindane and its metabolites may not be effectively cleared from the brain. The data suggest that low dose prenatal exposure to the pesticide has the potential to produce overexpression of xenobiotic metabolizing CYPs in brain and liver of the offspring which may account for the behavioral changes observed in the offspring.

Overexpression of cerebral and hepatic cytochrome P450s alters behavioral activity of rat offspring following prenatal exposure to lindane

International Nuclear Information System (INIS)

Johri, Ashu; Yadav, Sanjay; Dhawan, Alok; Parmar, Devendra

2007-01-01

Oral administration of different doses (0.0625, 0.125 or 0.25 mg/kg corresponding to 1/1400th, 1/700th or 1/350th of LD 50 ) of lindane to the pregnant Wistar rats from gestation days 5 to 21 were found to produce a dose-dependent increase in the activity of cytochrome P450 (CYP)-dependent 7-ethoxyresorufin-O-deethylase (EROD), 7-pentoxyresorufin-O-dealkylase (PROD) and N-nitrosodimethylamine demethylase (NDMA-d) in brain and liver of offspring postnatally at 3 weeks. The increase in the activity of CYP monooxygenases was found to be associated with the increase in the mRNA and protein expression of xenobiotic metabolizing CYP1A, 2B and 2E1 isoenzymes in the brain and liver of offspring. Dose-dependent alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 3 weeks have suggested that increase in CYP activity may possibly lead to the formation of metabolites to the levels that may be sufficient to alter the behavioral activity of the offspring. Interestingly, the inductive effect on cerebral and hepatic CYPs was found to persist postnatally up to 6 weeks in the offspring at the relatively higher doses (0.125 and 0.25 mg/kg) of lindane and up to 9 weeks at the highest dose (0.25 mg/kg), though the magnitude of induction was less than that observed at 3 weeks. Alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 6 and 9 weeks, though significant only in the offspring at 3 and 6-week of age, have further indicated that due to the reduced activity of the CYPs during the ontogeny, lindane and its metabolites may not be effectively cleared from the brain. The data suggest that low dose prenatal exposure to the pesticide has the potential to produce overexpression of xenobiotic metabolizing CYPs in brain and liver of the offspring which may account for the behavioral changes observed in the offspring

Deletion of Rictor in catecholaminergic neurons alters locomotor activity and ingestive behavior.

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Kaska, Sophia; Brunk, Rebecca; Bali, Vedrana; Kechner, Megan; Mazei-Robison, Michelle S

2017-05-01

While the etiology of depression is not fully understood, increasing evidence from animal models suggests a role for the ventral tegmental area (VTA) in pathogenesis. In this paper, we investigate the potential role of VTA mechanistic target of rapamycin 2 (TORC2) signaling in mediating susceptibility to chronic social defeat stress (CSDS), a well-established mouse model of depression. Utilizing genetic and viral knockout of Rictor (rapamycin-insensitive companion of target of rapamycin), a requisite component of TORC2, we demonstrate that decreasing Rictor-dependent TORC2 signaling in catecholaminergic neurons, or within the VTA specifically, does not alter susceptibility to CSDS. Opiate abuse and mood disorders are often comorbid, and previous data demonstrate a role for VTA TORC2 in mediating opiate reward. Thus, we also investigated its potential role in mediating changes in opiate reward following CSDS. Catecholaminergic deletion of Rictor increases water, sucrose, and morphine intake but not preference in a two-bottle choice assay in stress-naïve mice, and these effects are maintained after stress. VTA-specific knockout of Rictor increases water and sucrose intake after physical CSDS, but does not alter consummatory behavior in the absence of stress. These findings suggest a novel role for TORC2 in mediating stress-induced changes in consummatory behaviors that may contribute to some aspects of mood disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rapid recovery and altered neurochemical dependence of locomotor central pattern generation following lumbar neonatal spinal cord injury.

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Züchner, Mark; Kondratskaya, Elena; Sylte, Camilla B; Glover, Joel C; Boulland, Jean-Luc

2018-01-15

Spinal compression injury targeted to the neonatal upper lumbar spinal cord, the region of highest hindlimb locomotor rhythmogenicity, leads to an initial paralysis of the hindlimbs. Behavioural recovery is evident within a few days and approaches normal function within about 3 weeks. Fictive locomotion in the isolated injured spinal cord cannot be elicited by a neurochemical cocktail containing NMDA, dopamine and serotonin 1 day post-injury, but can 3 days post-injury as readily as in the uninjured spinal cord. Low frequency coordinated rhythmic activity can be elicited in the isolated uninjured spinal cord by NMDA + dopamine (without serotonin), but not in the isolated injured spinal cord. In both the injured and uninjured spinal cord, eliciting bona fide fictive locomotion requires the additional presence of serotonin. Following incomplete compression injury in the thoracic spinal cord of neonatal mice 1 day after birth (P1), we previously reported that virtually normal hindlimb locomotor function is recovered within about 3 weeks despite substantial permanent thoracic tissue loss. Here, we asked whether similar recovery occurs following lumbar injury that impacts more directly on the locomotor central pattern generator (CPG). As in thoracic injuries, lumbar injuries caused about 90% neuronal loss at the injury site and increased serotonergic innervation below the injury. Motor recovery was slower after lumbar than thoracic injury, but virtually normal function was attained by P25 in both cases. Locomotor CPG status was tested by eliciting fictive locomotion in isolated spinal cords using a widely used neurochemical cocktail (NMDA, dopamine, serotonin). No fictive locomotion could be elicited 1 day post-injury, but could within 3 days post-injury as readily as in age-matched uninjured control spinal cords. Burst patterning and coordination were largely similar in injured and control spinal cords but there were differences. Notably, in both groups there

Early application of tail nerve electrical stimulation-induced walking training promotes locomotor recovery in rats with spinal cord injury.

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Zhang, S-X; Huang, F; Gates, M; Shen, X; Holmberg, E G

2016-11-01

This is a randomized controlled prospective trial with two parallel groups. The objective of this study was to determine whether early application of tail nerve electrical stimulation (TANES)-induced walking training can improve the locomotor function. This study was conducted in SCS Research Center in Colorado, USA. A contusion injury to spinal cord T10 was produced using the New York University impactor device with a 25 -mm height setting in female, adult Long-Evans rats. Injured rats were randomly divided into two groups (n=12 per group). One group was subjected to TANES-induced walking training 2 weeks post injury, and the other group, as control, received no TANES-induced walking training. Restorations of behavior and conduction were assessed using the Basso, Beattie and Bresnahan open-field rating scale, horizontal ladder rung walking test and electrophysiological test (Hoffmann reflex). Early application of TANES-induced walking training significantly improved the recovery of locomotor function and benefited the restoration of Hoffmann reflex. TANES-induced walking training is a useful method to promote locomotor recovery in rats with spinal cord injury.

Disruption of locomotor adaptation with repetitive transcranial magnetic stimulation over the motor cortex

DEFF Research Database (Denmark)

Choi, Julia Tsok Lam; Bouyer, Laurent J; Nielsen, Jens Bo

2015-01-01

Locomotor patterns are adapted on a trial-and-error basis to account for predictable dynamics. Once a walking pattern is adapted, the new calibration is stored and must be actively de-adapted. Here, we tested the hypothesis that storage of newly acquired ankle adaptation in walking is dependent...

A single exercise bout and locomotor learning after stroke: physiological, behavioural, and computational outcomes.

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Charalambous, Charalambos C; Alcantara, Carolina C; French, Margaret A; Li, Xin; Matt, Kathleen S; Kim, Hyosub E; Morton, Susanne M; Reisman, Darcy S

2018-05-15

Previous work demonstrated an effect of a single high-intensity exercise bout coupled with motor practice on the retention of a newly acquired skilled arm movement, in both neurologically intact and impaired adults. In the present study, using behavioural and computational analyses we demonstrated that a single exercise bout, regardless of its intensity and timing, did not increase the retention of a novel locomotor task after stroke. Considering both present and previous work, we postulate that the benefits of exercise effect may depend on the type of motor learning (e.g. skill learning, sensorimotor adaptation) and/or task (e.g. arm accuracy-tracking task, walking). Acute high-intensity exercise coupled with motor practice improves the retention of motor learning in neurologically intact adults. However, whether exercise could improve the retention of locomotor learning after stroke is still unknown. Here, we investigated the effect of exercise intensity and timing on the retention of a novel locomotor learning task (i.e. split-belt treadmill walking) after stroke. Thirty-seven people post stroke participated in two sessions, 24 h apart, and were allocated to active control (CON), treadmill walking (TMW), or total body exercise on a cycle ergometer (TBE). In session 1, all groups exercised for a short bout (∼5 min) at low (CON) or high (TMW and TBE) intensity and before (CON and TMW) or after (TBE) the locomotor learning task. In both sessions, the locomotor learning task was to walk on a split-belt treadmill in a 2:1 speed ratio (100% and 50% fast-comfortable walking speed) for 15 min. To test the effect of exercise on 24 h retention, we applied behavioural and computational analyses. Behavioural data showed that neither high-intensity group showed greater 24 h retention compared to CON, and computational data showed that 24 h retention was attributable to a slow learning process for sensorimotor adaptation. Our findings demonstrated that acute exercise

Genetic KCa3.1-deficiency produces locomotor hyperactivity and alterations in cerebral monoamine levels.

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Kate Lykke Lambertsen

Full Text Available The calmodulin/calcium-activated K(+ channel KCa3.1 is expressed in red and white blood cells, epithelia and endothelia, and possibly central and peripheral neurons. However, our knowledge about its contribution to neurological functions and behavior is incomplete. Here, we investigated whether genetic deficiency or pharmacological activation of KCa3.1 change behavior and cerebral monoamine levels in mice.In the open field test, KCa3.1-deficiency increased horizontal activity, as KCa3.1(-/- mice travelled longer distances (≈145% of KCa3.1(+/+ and at higher speed (≈1.5-fold of KCa3.1(+/+. Working memory in the Y-maze was reduced by KCa3.1-deficiency. Motor coordination on the rotarod and neuromuscular functions were unchanged. In KCa3.1(-/- mice, HPLC analysis revealed that turn-over rates of serotonin were reduced in frontal cortex, striatum and brain stem, while noradrenalin turn-over rates were increased in the frontal cortex. Dopamine turn-over rates were unaltered. Plasma catecholamine and corticosterone levels were unaltered. Intraperitoneal injections of 10 mg/kg of the KCa3.1/KCa2-activator SKA-31 reduced rearing and turning behavior in KCa3.1(+/+ but not in KCa3.1(-/- mice, while 30 mg/kg SKA-31 caused strong sedation in 50% of the animals of either genotypes. KCa3.1(-/- mice were hyperactive (≈+60% in their home cage and SKA-31-administration reduced nocturnal physical activity in KCa3.1(+/+ but not in KCa3.1(-/- mice.KCa3.1-deficiency causes locomotor hyperactivity and altered monoamine levels in selected brain regions, suggesting a so far unknown functional link of KCa3.1 channels to behavior and monoaminergic neurotransmission in mice. The tranquilizing effects of low-dose SKA-31 raise the possibility to use KCa3.1/KCa2 channels as novel pharmacological targets for the treatment of neuropsychiatric hyperactivity disorders.

Locomotor Sub-functions for Control of Assistive Wearable Robots

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Maziar A. Sharbafi

2017-09-01

Full Text Available A primary goal of comparative biomechanics is to understand the fundamental physics of locomotion within an evolutionary context. Such an understanding of legged locomotion results in a transition from copying nature to borrowing strategies for interacting with the physical world regarding design and control of bio-inspired legged robots or robotic assistive devices. Inspired from nature, legged locomotion can be composed of three locomotor sub-functions, which are intrinsically interrelated: Stance: redirecting the center of mass by exerting forces on the ground. Swing: cycling the legs between ground contacts. Balance: maintaining body posture. With these three sub-functions, one can understand, design and control legged locomotory systems with formulating them in simpler separated tasks. Coordination between locomotor sub-functions in a harmonized manner appears then as an additional problem when considering legged locomotion. However, biological locomotion shows that appropriate design and control of each sub-function simplifies coordination. It means that only limited exchange of sensory information between the different locomotor sub-function controllers is required enabling the envisioned modular architecture of the locomotion control system. In this paper, we present different studies on implementing different locomotor sub-function controllers on models, robots, and an exoskeleton in addition to demonstrating their abilities in explaining humans' control strategies.

Locomotor Sub-functions for Control of Assistive Wearable Robots.

Science.gov (United States)

Sharbafi, Maziar A; Seyfarth, Andre; Zhao, Guoping

2017-01-01

A primary goal of comparative biomechanics is to understand the fundamental physics of locomotion within an evolutionary context. Such an understanding of legged locomotion results in a transition from copying nature to borrowing strategies for interacting with the physical world regarding design and control of bio-inspired legged robots or robotic assistive devices. Inspired from nature, legged locomotion can be composed of three locomotor sub-functions, which are intrinsically interrelated: Stance : redirecting the center of mass by exerting forces on the ground. Swing : cycling the legs between ground contacts. Balance : maintaining body posture. With these three sub-functions, one can understand, design and control legged locomotory systems with formulating them in simpler separated tasks. Coordination between locomotor sub-functions in a harmonized manner appears then as an additional problem when considering legged locomotion. However, biological locomotion shows that appropriate design and control of each sub-function simplifies coordination. It means that only limited exchange of sensory information between the different locomotor sub-function controllers is required enabling the envisioned modular architecture of the locomotion control system. In this paper, we present different studies on implementing different locomotor sub-function controllers on models, robots, and an exoskeleton in addition to demonstrating their abilities in explaining humans' control strategies.

NLRP3 inflammasome activation mediates fatigue-like behaviors in mice via neuroinflammation.

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Zhang, Ziteng; Ma, Xiujuan; Xia, Zhenna; Chen, Jikuai; Liu, Yangang; Chen, Yongchun; Zhu, Jiangbo; Li, Jinfeng; Yu, Huaiyu; Zong, Ying; Lu, Guocai

2017-09-01

Numerous experimental and clinical studies have suggested that the interaction between the immune system and the brain plays an important role in the pathophysiology of chronic fatigue syndrome (CFS). The NLRP3 inflammasome is an important part of the innate immune system. This complex regulates proinflammatory cytokine interleukin-1β (IL-1β) maturation, which triggers different kinds of immune-inflammatory reactions. We employed repeated forced swims to establish a model of CFS in mice. NLRP3 knockout (KO) mice were also used to explore NLRP3 inflammasome activation in the mechanisms of CFS, using the same treatment. After completing repeated swim tests, the mice displayed fatigue-like behaviors, including locomotor activity and reduced fall-off time on the rota-rod test, which was accompanied by significantly higher mature IL-1β level in the prefrontal cortex (PFC) and malondialdehyde (MDA) level in serum. We also found increased NLRP3 protein expression, NLRP3 inflammasome formation and increased mature IL-1β production in the PFC, relative to untreated mice. The NLRP3 KO mice displayed significantly moderated fatigue behaviors along with decreased PFC and serum IL-1β levels under the same treatment. These findings demonstrated the involvement of NLRP3 inflammasome activation in the mechanism of swimming-induced fatigue. Future therapies targeting the NLRP3/IL-1β pathway may have significant potential for fatigue prevention and treatment. Copyright © 2017. Published by Elsevier Ltd.

Proprioceptive input resets central locomotor rhythm in the spinal cat

DEFF Research Database (Denmark)

Conway, B. A.; Hultborn, H.; Kiehn, O.

1987-01-01

The reflex regulation of stepping is an important factor in adapting the step cycle to changes in the environment. The present experiments have examined the influence of muscle proprioceptors on centrally generated rhythmic locomotor activity in decerebrate unanesthetized cats with a spinal...... fictive locomotion in a coordinated fashion. An extensor group I volley delivered during a flexor burst would abruptly terminate the flexor activity and initiate an extensor burst. The same stimulus given during an extensor burst prolonged the extensor activity while delaying the appearance...... afferents. Thus an increased load of limb extensors during the stance phase would enhance and prolong extensor activity while simultaneously delaying the transition to the swing phase of the step cycle....

Vestibular lesion-induced developmental plasticity in spinal locomotor networks during Xenopus laevis metamorphosis.

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Beyeler, Anna; Rao, Guillaume; Ladepeche, Laurent; Jacques, André; Simmers, John; Le Ray, Didier

2013-01-01

During frog metamorphosis, the vestibular sensory system remains unchanged, while spinal motor networks undergo a massive restructuring associated with the transition from the larval to adult biomechanical system. We investigated in Xenopus laevis the impact of a pre- (tadpole stage) or post-metamorphosis (juvenile stage) unilateral labyrinthectomy (UL) on young adult swimming performance and underlying spinal locomotor circuitry. The acute disruptive effects on locomotion were similar in both tadpoles and juvenile frogs. However, animals that had metamorphosed with a preceding UL expressed restored swimming behavior at the juvenile stage, whereas animals lesioned after metamorphosis never recovered. Whilst kinematic and electrophysiological analyses of the propulsive system showed no significant differences in either juvenile group, a 3D biomechanical simulation suggested that an asymmetry in the dynamic control of posture during swimming could account for the behavioral restoration observed in animals that had been labyrinthectomized before metamorphosis. This hypothesis was subsequently supported by in vivo electromyography during free swimming and in vitro recordings from isolated brainstem/spinal cord preparations. Specifically, animals lesioned prior to metamorphosis at the larval stage exhibited an asymmetrical propulsion/posture coupling as a post-metamorphic young adult. This developmental alteration was accompanied by an ipsilesional decrease in propriospinal coordination that is normally established in strict left-right symmetry during metamorphosis in order to synchronize dorsal trunk muscle contractions with bilateral hindlimb extensions in the swimming adult. Our data thus suggest that a disequilibrium in descending vestibulospinal information during Xenopus metamorphosis leads to an altered assembly of adult spinal locomotor circuitry. This in turn enables an adaptive compensation for the dynamic postural asymmetry induced by the vestibular imbalance

Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

DEFF Research Database (Denmark)

Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

2011-01-01

Neurons of the brain's biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) generate circadian rhythms of physiology (core body temperature, hormone secretion, locomotor activity, sleep/wake, and heart rate) with distinct temporal phasing when entrained by the light/dark (LD......) cycle. The neuropeptide vasoactive intestinal polypetide (VIP) and its receptor (VPAC2) are highly expressed in the SCN. Recent studies indicate that VIPergic signaling plays an essential role in the maintenance of ongoing circadian rhythmicity by synchronizing SCN cells and by maintaining rhythmicity...... within individual neurons. To further increase the understanding of the role of VPAC2 signaling in circadian regulation, we implanted telemetric devices and simultaneously measured core body temperature, spontaneous activity, and heart rate in a strain of VPAC2-deficient mice and compared...

Comparative limb proportions reveal differential locomotor morphofunctions of alligatoroids and crocodyloids

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Iijima, Masaya; Kubo, Tai; Kobayashi, Yoshitsugu

2018-03-01

Although two major clades of crocodylians (Alligatoroidea and Crocodyloidea) were split during the Cretaceous period, relatively few morphological and functional differences between them have been known. In addition, interaction of multiple morphofunctional systems that differentiated their ecology has barely been assessed. In this study, we examined the limb proportions of crocodylians to infer the differences of locomotor functions between alligatoroids and crocodyloids, and tested the correlation of locomotor and feeding morphofunctions. Our analyses revealed crocodyloids including Gavialis have longer stylopodia (humerus and femur) than alligatoroids, indicating that two groups may differ in locomotor functions. Fossil evidence suggested that alligatoroids have retained short stylopodia since the early stage of their evolution. Furthermore, rostral shape, an indicator of trophic function, is correlated with limb proportions, where slender-snouted piscivorous taxa have relatively long stylopodia and short overall limbs. In combination, trophic and locomotor functions might differently delimit the ecological opportunity of alligatoroids and crocodyloids in the evolution of crocodylians.

Continuous exposure to a novel stressor based on water aversion induces abnormal circadian locomotor rhythms and sleep-wake cycles in mice.

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Koyomi Miyazaki

Full Text Available Psychological stressors prominently affect diurnal rhythms, including locomotor activity, sleep, blood pressure, and body temperature, in humans. Here, we found that a novel continuous stress imposed by the perpetual avoidance of water on a wheel (PAWW affected several physiological diurnal rhythms in mice. One week of PAWW stress decayed robust circadian locomotor rhythmicity, while locomotor activity was evident even during the light period when the mice are normally asleep. Daytime activity was significantly upregulated, whereas nighttime activity was downregulated, resulting in a low amplitude of activity. Total daily activity gradually decreased with increasing exposure to PAWW stress. The mice could be exposed to PAWW stress for over 3 weeks without adaptation. Furthermore, continuous PAWW stress enhanced food intake, but decreased body weight and plasma leptin levels, indicating that sleep loss and PAWW stress altered the energy balance in these mice. The diurnal rhythm of corticosterone levels was not severely affected. The body temperature rhythm was diurnal in the stressed mice, but significantly dysregulated during the dark period. Plasma catecholamines were elevated in the stressed mice. Continuous PAWW stress reduced the duration of daytime sleep, especially during the first half of the light period, and increased nighttime sleepiness. Continuous PAWW stress also simultaneously obscured sleep/wake and locomotor activity rhythms compared with control mice. These sleep architecture phenotypes under stress are similar to those of patients with insomnia. The stressed mice could be entrained to the light/dark cycle, and when they were transferred to constant darkness, they exhibited a free-running circadian rhythm with a timing of activity onset predicted by the phase of their entrained rhythms. Circadian gene expression in the liver and muscle was unaltered, indicating that the peripheral clocks in these tissues remained intact.

First laboratory insight on the behavioral rhythms of the bathyal crab Geryon longipes

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Nuñez, J. D.; Sbragaglia, V.; García, J. A.; Company, J. B.; Aguzzi, J.

2016-10-01

The deep sea is the largest and at the same time least explored biome on Earth, but quantitative studies on the behavior of bathyal organisms are scarce because of the intrinsic difficulties related to in situ observations and maintaining animals in aquaria. In this study, we reported, for the first time, laboratory observations on locomotor rhythms and other behavioral observations (i.e. feeding, exploring and self-grooming) for the bathyal crab Geryon longipes. Crabs were collected on the middle-lower slope (720-1750 m) off the coast of Blanes (Spain). Inertial (18 h) water currents and monochromatic blue (i.e. 470 nm) light-darkness (24 h) cycles were simulated in two different experiments in flume tanks endowed with burrows. Both cycles were simulated in order to investigate activity rhythms regulation in Mediterranean deep-sea benthos. Crabs showed rhythmic locomotor activity synchronized to both water currents and light-darkness cycles. In general terms, feeding and exploring behaviors also followed the same pattern. Results presented here indicate the importance of local inertial (18 h) periodicity of water currents at the seabed as a temporal cue regulating the behavior of bathyal benthic fauna in all continental margin areas where the effects of tides is negligible.

Effects of repeated exposure to malathion on growth, food consumption, and locomotor performance of the western fence lizard (Sceloporus occidentalis)

International Nuclear Information System (INIS)

Holem, Ryan R.; Hopkins, William A.; Talent, Larry G.

2008-01-01

Effects of repeated pollutant exposure on growth, locomotor performance, and behavior have rarely been evaluated in reptiles. We administered three doses of malathion (2.0, 20, or 100 mg/kg body weight) to western fence lizards (Sceloporus occidentalis) over an 81 day period. Eight and 23% mortality occurred at 20 and 100 mg/kg (p = 0.079) and 85% of lizards in the 100 mg/kg group exhibited clinical symptoms of poisoning. Growth, food consumption, body condition index, and terrestrial locomotor performance were not significantly influenced by malathion. However, arboreal sprint velocity was significantly reduced in lizards receiving 100 mg/kg. Fifty percent of lizards in the 100 mg/kg group also refused to sprint in the arboreal setting (p = 0.085). Based on these results, arboreal locomotor performance was the most sensitive metric of exposure we evaluated. Further study of compounds such as malathion is warranted due to highly variable application rates and exposure scenarios. - Repeated exposure of western fence lizards to malathion caused reduced arboreal performance and some mortality but growth, food consumption, and terrestrial performance were not affected

Effects of repeated exposure to malathion on growth, food consumption, and locomotor performance of the western fence lizard (Sceloporus occidentalis)

Energy Technology Data Exchange (ETDEWEB)

Holem, Ryan R. [University of Georgia, Savannah River Ecology Laboratory, Aiken, SC 29801 (United States); ENTRIX, Inc., Okemos, MI 48864 (United States); Hopkins, William A. [University of Georgia, Savannah River Ecology Laboratory, Aiken, SC 29801 (United States); Department of Fisheries and Wildlife Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)], E-mail: hopkinsw@vt.edu; Talent, Larry G. [Natural Resource Ecology and Management, Oklahoma State University, Stillwater, OK 74078 (United States)

2008-03-15

Effects of repeated pollutant exposure on growth, locomotor performance, and behavior have rarely been evaluated in reptiles. We administered three doses of malathion (2.0, 20, or 100 mg/kg body weight) to western fence lizards (Sceloporus occidentalis) over an 81 day period. Eight and 23% mortality occurred at 20 and 100 mg/kg (p = 0.079) and 85% of lizards in the 100 mg/kg group exhibited clinical symptoms of poisoning. Growth, food consumption, body condition index, and terrestrial locomotor performance were not significantly influenced by malathion. However, arboreal sprint velocity was significantly reduced in lizards receiving 100 mg/kg. Fifty percent of lizards in the 100 mg/kg group also refused to sprint in the arboreal setting (p = 0.085). Based on these results, arboreal locomotor performance was the most sensitive metric of exposure we evaluated. Further study of compounds such as malathion is warranted due to highly variable application rates and exposure scenarios. - Repeated exposure of western fence lizards to malathion caused reduced arboreal performance and some mortality but growth, food consumption, and terrestrial performance were not affected.

Light pollution reduces activity, food consumption and growth rates in a sandy beach invertebrate.

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Luarte, T; Bonta, C C; Silva-Rodriguez, E A; Quijón, P A; Miranda, C; Farias, A A; Duarte, C

2016-11-01

The continued growth of human activity and infrastructure has translated into a widespread increase in light pollution. Natural daylight and moonlight cycles play a fundamental role for many organisms and ecological processes, so an increase in light pollution may have profound effects on communities and ecosystem services. Studies assessing ecological light pollution (ELP) effects on sandy beach organisms have lagged behind the study of other sources of disturbance. Hence, we assessed the influence of this stressor on locomotor activity, foraging behavior, absorption efficiency and growth rate of adults of the talitrid amphipod Orchestoidea tuberculata. In the field, an artificial light system was assembled to assess the local influence of artificial light conditions on the amphipod's locomotor activity and use of food patches in comparison to natural (ambient) conditions. Meanwhile in the laboratory, two experimental chambers were set to assess amphipod locomotor activity, consumption rates, absorption efficiency and growth under artificial light in comparison to natural light-dark cycles. Our results indicate that artificial light have significantly adverse effects on the activity patterns and foraging behavior of the amphipods, resulting on reduced consumption and growth rates. Given the steady increase in artificial light pollution here and elsewhere, sandy beach communities could be negatively affected, with unexpected consequences for the whole ecosystem. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prevention of disorders of behavioral reactions in rats using nootropics with sodium valproate

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Ivanov A.V.

2013-06-01

Full Text Available Using of anticonvulsants can trigger a number of side effects, such as possible changes in behavior and emotional state of people with epilepsy, risk of unwarranted aggression, nervousness, discoordination, sleepiness, encephalopathies. However, the epilepsy itself as a chronic neurological pathology causes cognitive and "epileptic" deficiency, in patients general retardation, sluggishness of mental activity, decreased cognitive abilities de¬velop. Therefore it is advisable to combine anticonvulsants with nootropics with their ability to protect the brain and increase body's resistance to extreme stress, reduce neurological deficits, restore damaged mnestic and mental functions. The author considered the use of nootropics on the background of anticonvulsant sodium valproate (80 mg/kg. Behavioral reactions of white rats in the test "Open field" and muscle tone of white mice in the test "muscle relaxation" were performed on the day 4 nootropics introduction in 1 hour after a single sodium valproate application. It’s shown experimentally that sodium valproate provided systemic depriming action on orientation and exploratory activity of rats: locomotor activity reduced in the number of squares strolled by 62.8% and in the number of vertical uprights by 80%, the amount of peeping into the burrows decreased by 58.7% as compared with the control. In the test "muscle relaxation" sodium valproate reduced muscle strength of mice by 38.6%. Against the background of anticonvulsant application piracetam (500 mg/kg had no effect on the behavioral responses of rats and muscle tone of mice. Citicoline (500 mg/kg increased locomotor activity in the number of squares crossed by 29.7%, in the number of vertical racks – by 20%, and the endurance of mice by 18.6%. Memantine (10 mg/kg in combination with sodium valproate insignificantly decreased (by 8.4% locomotor activity of rats, but increased exploratory activity by 30.5%; withholding of mice on the wire

Integrated Locomotor Function Tests for Countermeasure Evaluation

Science.gov (United States)

Bloomberg, J. J.; Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Landsness, E. C.; Black, F. O.

2005-01-01

Following spaceflight crewmembers experience locomotor dysfunction due to inflight adaptive alterations in sensorimotor function. Countermeasures designed to mitigate these postflight gait alterations need to be assessed with a new generation of tests that evaluate the interaction of various sensorimotor sub-systems central to locomotor control. The goal of the present study was to develop new functional tests of locomotor control that could be used to test the efficacy of countermeasures. These tests were designed to simultaneously examine the function of multiple sensorimotor systems underlying the control of locomotion and be operationally relevant to the astronaut population. Traditionally, gaze stabilization has been studied almost exclusively in seated subjects performing target acquisition tasks requiring only the involvement of coordinated eye-head movements. However, activities like walking involve full-body movement and require coordination between lower limbs and the eye-head-trunk complex to achieve stabilized gaze during locomotion. Therefore the first goal of this study was to determine how the multiple, interdependent, full-body sensorimotor gaze stabilization subsystems are functionally coordinated during locomotion. In an earlier study we investigated how alteration in gaze tasking changes full-body locomotor control strategies. Subjects walked on a treadmill and either focused on a central point target or read numeral characters. We measured: temporal parameters of gait, full body sagittal plane segmental kinematics of the head, trunk, thigh, shank and foot, accelerations along the vertical axis at the head and the shank, and the vertical forces acting on the support surface. In comparison to the point target fixation condition, the results of the number reading task showed that compensatory head pitch movements increased, peak head acceleration was reduced and knee flexion at heel-strike was increased. In a more recent study we investigated the

Transgenic APP expression during postnatal development causes persistent locomotor hyperactivity in the adult.

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Rodgers, Shaefali P; Born, Heather A; Das, Pritam; Jankowsky, Joanna L

2012-06-18

Transgenic mice expressing disease-associated proteins have become standard tools for studying human neurological disorders. Transgenes are often expressed using promoters chosen to drive continuous high-level expression throughout life rather than temporal and spatial fidelity to the endogenous gene. This approach has allowed us to recapitulate diseases of aging within the two-year lifespan of the laboratory mouse, but has the potential for creating aberrant phenotypes by mechanisms unrelated to the human disorder. We show that overexpression of the Alzheimer's-related amyloid precursor protein (APP) during early postnatal development leads to severe locomotor hyperactivity that can be significantly attenuated by delaying transgene onset until adulthood. Our data suggest that exposure to transgenic APP during maturation influences the development of neuronal circuits controlling motor activity. Both when matched for total duration of APP overexpression and when matched for cortical amyloid burden, animals exposed to transgenic APP as juveniles are more active in locomotor assays than animals in which APP overexpression was delayed until adulthood. In contrast to motor activity, the age of APP onset had no effect on thigmotaxis in the open field as a rough measure of anxiety, suggesting that the interaction between APP overexpression and brain development is not unilateral. Our findings indicate that locomotor hyperactivity displayed by the tet-off APP transgenic mice and several other transgenic models of Alzheimer's disease may result from overexpression of mutant APP during postnatal brain development. Our results serve as a reminder of the potential for unexpected interactions between foreign transgenes and brain development to cause long-lasting effects on neuronal function in the adult. The tet-off APP model provides an easy means of avoiding developmental confounds by allowing transgene expression to be delayed until the mice reach adulthood.

CREB activity in dopamine D1 receptor expressing neurons regulates cocaine-induced behavioral effects

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Bilbao, Ainhoa; Rieker, Claus; Cannella, Nazzareno; Parlato, Rosanna; Golda, Slawomir; Piechota, Marcin; Korostynski, Michal; Engblom, David; Przewlocki, Ryszard; Schütz, Günther; Spanagel, Rainer; Parkitna, Jan R.

2014-01-01

It is suggested that striatal cAMP responsive element binding protein (CREB) regulates sensitivity to psychostimulants. To test the cell-specificity of this hypothesis we examined the effects of a dominant-negative CREB protein variant expressed in dopamine receptor D1 (D1R) neurons on cocaine-induced behaviors. A transgenic mouse strain was generated by pronuclear injection of a BAC-derived transgene harboring the A-CREB sequence under the control of the D1R gene promoter. Compared to wild-type, drug-naïve mutants showed moderate alterations in gene expression, especially a reduction in basal levels of activity-regulated transcripts such as Arc and Egr2. The behavioral responses to cocaine were elevated in mutant mice. Locomotor activity after acute treatment, psychomotor sensitization after intermittent drug injections and the conditioned locomotion after saline treatment were increased compared to wild-type littermates. Transgenic mice had significantly higher cocaine conditioned place preference, displayed normal extinction of the conditioned preference, but showed an augmented cocaine-seeking response following priming-induced reinstatement. This enhanced cocaine-seeking response was associated with increased levels of activity-regulated transcripts and prodynorphin. The primary reinforcing effects of cocaine were not altered in the mutant mice as they did not differ from wild-type in cocaine self-administration under a fixed ratio schedule at the training dose. Collectively, our data indicate that expression of a dominant-negative CREB variant exclusively in neurons expressing D1R is sufficient to recapitulate the previously reported behavioral phenotypes associated with virally expressed dominant-negative CREB. PMID:24966820

Can prenatal low-dose irradiation affect behavior of adult rats?

International Nuclear Information System (INIS)

Smajda, B.; Tomasova, L.; Kokocova, N.

2011-01-01

The aim of our study was to determine whether exposure of very low dose gamma-rays during the critical phase of brain development affects some selected behavioral parameters in adult rats. Pregnant female Wistar rats were irradiated with 1 Gy gamma-rays from a cobalt source at 17 th day of pregnancy. The progeniture of irradiated as well as non-irradiated females have undergone behavioral tests at the age of 3 months. Irradiated animals exhibited lower locomotor and exploratory activity in the open field test. (authors)

Behavioral effects of α,α,β,β-tetradeutero-5-MeO-DMT in rats: comparison with 5-MeO-DMT administered in combination with a monoamine oxidase inhibitor

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Halberstadt, Adam L.; Nichols, David E.; Geyer, Mark A.

2012-01-01

RATIONALE Ayahuasca is a psychoactive tea prepared from a combination of plants that contain a hallucinogenic tryptamine and monoamine oxidase inhibitors (MAOIs). Behavioral Pattern Monitor (BPM) experiments demonstrated that the combination of 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and a behaviorally inactive dose of an MAOA inhibitor such as harmaline or clorgyline induces biphasic effects on locomotor activity in rats, initially reducing locomotion and then increasing activity as time progresses. OBJECTIVES The present study investigated whether the biphasic locomotor profile induced by the combination of 5-MeO-DMT and an MAOI is a consequence of a reduction in the rate of 5-MeO-DMT metabolism. This hypothesis was tested using a deuterated derivative of 5-MeO-DMT (α,α,β,β-tetradeutero-5-MeO-DMT) that is resistant to metabolism by MAO. RESULTS Confirming our previous findings, 1.0 mg/kg 5-MeO-DMT (s.c.) had biphasic effects on locomotor activity in rats pretreated with a behaviorally inactive dose of the nonselective MAOI pargyline (10 mg/kg). Administration of 5-MeO-DMT alone, even at doses greater than 1.0 mg/kg, produced only reductions in locomotor activity. Although low doses of α,α,β,β-tetradeutero-5-MeO-DMT (0.3 and 1.0 mg/kg, s.c.) produced only hypoactivity in the BPM, a dose of 3.0 mg/kg induced a biphasic locomotor profile similar to that produced by the combination of 5-MeO-DMT and an MAOI. Receptor binding studies demonstrated that deuterium substitution had little effect on the affinity of 5-MeO-DMT for a wide variety of neurotransmitter binding sites. CONCLUSIONS The finding with α,α,β,β-tetradeutero-5-MeO-DMT indicates that the hyperactivity induced by 5-MeO-DMT after MAO inhibition is a consequence of reduced metabolism of 5-MeO-DMT, leading to prolonged occupation of central serotonin receptors. These results demonstrate that deuterated tryptamines may be useful in behavioral and pharmacological studies to mimic the effects of

M100907 attenuates elevated grooming behavior in the BTBR mouse.

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Amodeo, Dionisio A; Rivera, Elaine; Dunn, Jeffrey T; Ragozzino, Michael E

2016-10-15

Individuals with autism spectrum disorder (ASD) exhibit social-communication deficits along with restricted interests and repetitive behaviors (RRBs). To date, there is a lack of effective treatments to alleviate RRBs. A recent study found that treatment with the 5HT2A receptor antagonist M100907 attenuates a reversal learning deficit in the BTBR mouse model of autism. The BTBR mouse also exhibits elevated grooming behavior which may model stereotyped motor behaviors also observed in ASD. The present study examined whether 5HT2A receptor blockade with M100907 at either 0.01 or 0.1mg/kg can reduce repetitive grooming in BTBR mice compared to that of vehicle-treated BTBR and C57BL6/J (B6) mice. M100907 at 0.1mg/kg, but not 0.01mg/kg, significantly attenuated repetitive grooming in BTBR mice compared to that of vehicle-treated BTBR mice. M100907 at either dose did not affect grooming behavior in B6 mice. To determine whether 0.1mg/kg M100907 had a more general effect on activity in BTBR mice, a second experiment determined whether M100907 at 0.1mg/kg affected locomotor activity in BTBR mice. M100907 treatment in BTBR and B6 mice did not alter locomotor activity compared to that of vehicle-treated BTBR and B6 mice. The present findings taken together with past results suggest that treatment with a 5HT2A receptor antagonist may be effective in ameliorating RRBs in ASD. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of Wearing a Telemetry Jacket on Behavioral and Physiologic Parameters of Dogs in the Open-Field Test.

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Fish, Richard E; Foster, Melanie L; Gruen, Margaret E; Sherman, Barbara L; Dorman, Davidc C

2017-07-01

Safety pharmacology studies in dogs often integrate behavioral assessments made using video recording with physiologic measurements collected by telemetry. However, whether merely wearing the telemetry vest affects canine behavior and other parameters has not been evaluated. This pilot study assessed the effect of a telemetry vest on behavioral and physiologic responses to an environmental stressor, the sounds of a thunderstorm, in Labrador retrievers. Dogs were assigned to one of 2 experimental groups (Vest and No-Vest, n = 8 dogs per group) by using a matched pairs design, with a previously determined, sound-associated anxiety score as the blocking variable. Dogs were individually retested with the same standardized sound stimulus (thunderstorm) in an open-field arena, and their behavioral responses were video recorded. Video analysis of locomotor activity and anxiety-related behavior and manual determination of heart rate and body temperature were performed; results were compared between groups. Vest wearing did not affect total locomotor activity or rectal body temperature but significantly decreased heart rate by 8% and overall mean anxiety score by 34% during open-field test sessions. Our results suggest that the use of telemetry vests in dogs influences the measurement of physiologic parameters and behaviors that are assessed in safety pharmacology studies.

Sex differences in locomotor effects of morphine in the rat

OpenAIRE

Craft, Rebecca M.; Clark, James L.; Hart, Stephen P.; Pinckney, Megan K.

2006-01-01

Sex differences in reinforcing, analgesic and other effects of opioids have been demonstrated; however, the extent to which sex differences in motoric effects of opioids contribute to apparent sex differences in their primary effects is not known. The goal of this study was to compare the effects of the prototypic mu opioid agonist morphine on locomotor activity in male vs. female rats. Saline or morphine (1-10 mg/kg) was administered s.c. to adult Sprague-Dawley rats, which were placed into ...

The time of day differently influences fatigue and locomotor activity: is body temperature a key factor?

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Machado, Frederico Sander Mansur; Rodovalho, Gisele Vieira; Coimbra, Cândido Celso

2015-03-01

The aim of this study was to verify the possible interactions between exercise capacity and spontaneous locomotor activity (SLA) during the oscillation of core body temperature (Tb) that occurs during the light/dark cycle. Wistar rats (n=11) were kept at an animal facility under a light/dark cycle of 14/10h at an ambient temperature of 23°C and water and food ad libitum. Initially, in order to characterize the daily oscillation in SLA and Tb of the rats, these parameters were continuously recorded for 24h using an implantable telemetric sensor (G2 E-Mitter). The animals were randomly assigned to two progressive exercise test protocols until fatigue during the beginning of light and dark-phases. Fatigue was defined as the moment rats could not keep pace with the treadmill. We assessed the time to fatigue, workload and Tb changes induced by exercise. Each test was separated by 3days. Our results showed that exercise capacity and heat storage were higher during the light-phase (plocomotor physical activity have an important inherent component (r=0.864 and r=0.784, respectively, plocomotor activity are not directly associated, both are strongly influenced by daily cycles of light and dark. Copyright © 2014 Elsevier Inc. All rights reserved.

Regulation of Akt-mTOR, ubiquitin-proteasome and autophagy-lysosome pathways in locomotor and respiratory muscles during experimental sepsis in mice.

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Morel, Jérome; Palao, Jean-Charles; Castells, Josiane; Desgeorges, Marine; Busso, Thierry; Molliex, Serge; Jahnke, Vanessa; Del Carmine, Peggy; Gondin, Julien; Arnould, David; Durieux, Anne Cécile; Freyssenet, Damien

2017-09-07

Sepsis induced loss of muscle mass and function contributes to promote physical inactivity and disability in patients. In this experimental study, mice were sacrificed 1, 4, or 7 days after cecal ligation and puncture (CLP) or sham surgery. When compared with diaphragm, locomotor muscles were more prone to sepsis-induced muscle mass loss. This could be attributed to a greater activation of ubiquitin-proteasome system and an increased myostatin expression. Thus, this study strongly suggests that the contractile activity pattern of diaphragm muscle confers resistance to atrophy compared to the locomotor gastrocnemius muscle. These data also suggest that a strategy aimed at preventing the activation of catabolic pathways and preserving spontaneous activity would be of interest for the treatment of patients with sepsis-induced neuromyopathy.

Locomotor inhibition in adults horses faced to stressors: a single postpartum experience may be enough!

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Virginie eDurier

2012-10-01

Full Text Available Despite the number of postpartum handling that a newborn experiences, few studies focus on their long-term consequences. In rats, regular long separations from the mother, during the early life, led to modifications of the locomotor activity when the animal is confronted to a stressor. In horses, one component of the behavioural response to stressful situation is active locomotion. We wondered if the routine postpartum handling undergone by foals, would affect their level of reactivity or the way they express their stress, when older. One single prolonged bout of handling just after birth clearly affected later adult expression of stress reactivity. In social separation associated with novelty, handled and unhandled horses produced an equal amount of whinnies, showing a similar vocal response to stress. However, both groups differed in their locomotor response to the situations. Early-handled foals expressed less of the active forms of locomotion than the control group. Our findings highlight the need of further reflections on long-term effects of routine handlings procedures close to birth.

Age influences the effects of nicotine and monoamine oxidase inhibition on mood-related behaviors in rats.

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Villégier, Anne-Sophie; Gallager, Brittney; Heston, Jon; Belluzzi, James D; Leslie, Frances M

2010-03-01

Epidemiological studies have demonstrated a comorbidity of smoking with depression and anxiety, particularly during adolescence. However, few animal studies have considered possible synergistic interactions between nicotine and other tobacco smoke constituents, such as monoamine oxidase (MAO) inhibitors, in the regulation of mood. The aim of the study was to test the hypothesis that nicotine combined with the irreversible MAO inhibitor, tranylcypromine, will differentially affect depression- and anxiety-related behaviors in adolescent and adult rats. Nicotine (0, 0.05, 0.2 mg/kg, s.c.) and tranylcypromine (3 mg/kg, i.p.) were tested separately, or together, on male rats aged postnatal days 30 and 68, in three mood-related behavioral tests: forced swim test (FST), elevated plus maze (EPM), and open field. Nicotine (0.2 mg/kg) in adults significantly decreased floating time in the FST and increased time spent in the open arm of the EPM, with no change in locomotor activity. Tranylcypromine pretreatment combined with nicotine (0.2 mg/kg) significantly increased locomotor activity and time spent in the center of the open field. Whereas nicotine alone had no significant effect on adolescents, it significantly increased locomotor activity and decreased floating time in the FST when combined with tranylcypromine pretreatment. There is an age-dependent effect of nicotine, alone and in combination with MAO inhibition, on mood-related behaviors. Whereas nicotine alone induces mood improvement in adults, it has no effect on adolescents. Nicotine combined with tranylcypromine has unique, age-dependent effects. Thus, experimental studies of smoking should consider both age and other tobacco constituents, such as MAO inhibitors, as critical factors.

Effects of methamphetamine exposure on anxiety-like behavior in the open field test, corticosterone, and hippocampal tyrosine hydroxylase in adolescent and adult mice.

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Struntz, Katelyn H; Siegel, Jessica A

2018-08-01

Methamphetamine (MA) is a psychomotor stimulant drug that can alter behavior, the stress response system, and the dopaminergic system. The effects of MA can be modulated by age, however relatively little research has examined the acute effects of MA in adolescents and how the effects compare to those found in adults. The hippocampal dopamine system is altered by MA exposure and can modulate anxiety-like behavior, but the effects of MA on the hippocampal dopamine system have not been well studied, especially in adolescent animals. In order to assess potential age differences in the effects of MA exposure, this research examined the effects of acute MA exposure on locomotor and anxiety-like behavior in the open field test, plasma corticosterone levels, and hippocampal total tyrosine hydroxylase and phosphorylated tyrosine hydroxylase levels in adolescent and adult male C57BL/6 J mice. Tyrosine hydroxylase is the rate limiting enzyme in the synthesis of dopamine and was used as a marker of the hippocampal dopaminergic system. Mice were exposed to saline or 4 mg/kg MA and locomotor and anxiety-like behavior were measured in the open field test. Serum and brains were collected immediately after testing and plasma corticosterone and hippocampal total tyrosine hydroxylase and phosphorylated tyrosine hydroxylase levels measured. MA-exposed mice showed increased locomotor activity and anxiety-like behavior in the open field test compared with saline controls, regardless of age. There was no effect of MA on plasma corticosterone levels or hippocampal total tyrosine hydroxylase or phosphorylated tyrosine hydroxylase levels in either adolescent or adult mice. These data suggest that acute MA exposure during adolescence and adulthood increases locomotor activity and anxiety-like behavior but does not alter plasma corticosterone levels or hippocampal total tyrosine hydroxylase or phosphorylated tyrosine hydroxylase levels, and that these effects are not modulated by age

Neurochemical and behavioral characterization of neuronal glutamate transporter EAAT3 heterozygous mice

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Luis F. González

2017-10-01

Full Text Available Abstract Background Obsessive–compulsive disorder (OCD is a severe neuropsychiatric condition affecting 1–3% of the worldwide population. OCD has a strong genetic component, and the SLC1A1 gene that encodes neuronal glutamate transporter EAAT3 is a strong candidate for this disorder. To evaluate the impact of reduced EAAT3 expression in vivo, we studied male EAAT3 heterozygous and wild-type littermate mice using a battery of behavioral paradigms relevant to anxiety (open field test, elevated plus maze and compulsivity (marble burying, as well as locomotor activity induced by amphetamine. Using high-performance liquid chromatography, we also determined tissue neurotransmitter levels in cortex, striatum and thalamus—brain areas that are relevant to OCD. Results Compared to wild-type littermates, EAAT3 heterozygous male mice have unaltered baseline anxiety-like, compulsive-like behavior and locomotor activity. Administration of acute amphetamine (5 mg/kg intraperitoneally increased locomotion with no differences across genotypes. Tissue levels of glutamate, GABA, dopamine and serotonin did not vary between EAAT3 heterozygous and wild-type mice. Conclusions Our results indicate that reduced EAAT3 expression does not impact neurotransmitter content in the corticostriatal circuit nor alter anxiety or compulsive-like behaviors.

Learning a locomotor task: with or without errors?

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Marchal-Crespo, Laura; Schneider, Jasmin; Jaeger, Lukas; Riener, Robert

2014-03-04

Robotic haptic guidance is the most commonly used robotic training strategy to reduce performance errors while training. However, research on motor learning has emphasized that errors are a fundamental neural signal that drive motor adaptation. Thus, researchers have proposed robotic therapy algorithms that amplify movement errors rather than decrease them. However, to date, no study has analyzed with precision which training strategy is the most appropriate to learn an especially simple task. In this study, the impact of robotic training strategies that amplify or reduce errors on muscle activation and motor learning of a simple locomotor task was investigated in twenty two healthy subjects. The experiment was conducted with the MAgnetic Resonance COmpatible Stepper (MARCOS) a special robotic device developed for investigations in the MR scanner. The robot moved the dominant leg passively and the subject was requested to actively synchronize the non-dominant leg to achieve an alternating stepping-like movement. Learning with four different training strategies that reduce or amplify errors was evaluated: (i) Haptic guidance: errors were eliminated by passively moving the limbs, (ii) No guidance: no robot disturbances were presented, (iii) Error amplification: existing errors were amplified with repulsive forces, (iv) Noise disturbance: errors were evoked intentionally with a randomly-varying force disturbance on top of the no guidance strategy. Additionally, the activation of four lower limb muscles was measured by the means of surface electromyography (EMG). Strategies that reduce or do not amplify errors limit muscle activation during training and result in poor learning gains. Adding random disturbing forces during training seems to increase attention, and therefore improve motor learning. Error amplification seems to be the most suitable strategy for initially less skilled subjects, perhaps because subjects could better detect their errors and correct them

Effects of ayahuasca on the development of ethanol-induced behavioral sensitization and on a post-sensitization treatment in mice.

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Oliveira-Lima, A J; Santos, R; Hollais, A W; Gerardi-Junior, C A; Baldaia, M A; Wuo-Silva, R; Yokoyama, T S; Costa, J L; Malpezzi-Marinho, E L A; Ribeiro-Barbosa, P C; Berro, L F; Frussa-Filho, R; Marinho, E A V

2015-04-01

Hallucinogenic drugs were used to treat alcoholic patients in the past, and recent developments in the study of hallucinogens led to a renewal of interest regarding the application of these drugs in the treatment of addiction. In this scenario, accumulating evidence suggests that the hallucinogenic brew ayahuasca (Aya) may have therapeutic effects on substance abuse problems. We investigated the effects of Aya on spontaneous locomotor activity and ethanol(Eth)-induced hyperlocomotion and subsequent locomotor sensitization by a two-injection protocol. Additionally, we tested the effect of Aya on an 8-day counter-sensitization protocol to modify sensitized responses induced by a repeated treatment with Eth (1.8g/kg) for 8 alternate days. Aya showed high sensitivity in preventing the development of Eth-induced behavioral sensitization, attenuating it at all doses (30, 100, 200, 300 or 500 mg/kg) without modifying spontaneous locomotor activity. At the highest doses (300 and 500 mg/kg), Aya also showed selectivity to both acute and sensitized Eth responses. Finally, a counter-sensitization strategy with 100 or 300 mg/kg of Aya for 8 consecutive days after the establishment of Eth-induced behavioral sensitization was effective in blocking its subsequent expression on an Eth challenge. We demonstrated that Aya not only inhibits early behaviors associated with the initiation and development of Eth addiction, but also showed effectiveness in reversing long-term drug effects expression, inhibiting the reinstatement of Eth-induced behavioral sensitization when administered in the Eth-associated environment. Copyright © 2015 Elsevier Inc. All rights reserved.

Circadian and dark-pulse activation of orexin/hypocretin neurons

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Marston Oliver J

2008-12-01

Full Text Available Temporal control of brain and behavioral states emerges as a consequence of the interaction between circadian and homeostatic neural circuits. This interaction permits the daily rhythm of sleep and wake, regulated in parallel by circadian cues originating from the suprachiasmatic nuclei (SCN and arousal-promoting signals arising from the orexin-containing neurons in the tuberal hypothalamus (TH. Intriguingly, the SCN circadian clock can be reset by arousal-promoting stimuli while activation of orexin/hypocretin neurons is believed to be under circadian control, suggesting the existence of a reciprocal relationship. Unfortunately, since orexin neurons are themselves activated by locomotor promoting cues, it is unclear how these two systems interact to regulate behavioral rhythms. Here mice were placed in conditions of constant light, which suppressed locomotor activity, but also revealed a highly pronounced circadian pattern in orexin neuronal activation. Significantly, activation of orexin neurons in the medial and lateral TH occurred prior to the onset of sustained wheel-running activity. Moreover, exposure to a 6 h dark pulse during the subjective day, a stimulus that promotes arousal and phase advances behavioral rhythms, activated neurons in the medial and lateral TH including those containing orexin. Concurrently, this stimulus suppressed SCN activity while activating cells in the median raphe. In contrast, dark pulse exposure during the subjective night did not reset SCN-controlled behavioral rhythms and caused a transient suppression of neuronal activation in the TH. Collectively these results demonstrate, for the first time, pronounced circadian control of orexin neuron activation and implicate recruitment of orexin cells in dark pulse resetting of the SCN circadian clock.

Loss of Sphingosine Kinase Alters Life History Traits and Locomotor Function in Caenorhabditis elegans

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Jason P. Chan

2017-09-01

Full Text Available Sphingolipid metabolism is important to balance the abundance of bioactive lipid molecules involved in cell signaling, neuronal function, and survival. Specifically, the sphingolipid sphingosine mediates cell death signaling, whereas its phosphorylated form, sphingosine-1-phosphate (S1P, mediates cell survival signaling. The enzyme sphingosine kinase produces S1P, and the activity of sphingosine kinase impacts the ability of cells to survive under stress and challenges. To examine the influence of sphingolipid metabolism, particularly enzymes regulating sphingosine and S1P, in mediating aging, neuronal function and stress response, we examined life history traits, locomotor capacities and heat stress responses of young and old animals using the model organism Caenorhabditis elegans. We found that C. elegans sphk-1 mutants, which lack sphingosine kinase, had shorter lifespans, reduced brood sizes, and smaller body sizes compared to wild type animals. By analyzing a panel of young and old animals with genetic mutations in the sphingolipid signaling pathway, we showed that aged sphk-1 mutants exhibited a greater decline in neuromuscular function and locomotor behavior. In addition, aged animals lacking sphk-1 were more susceptible to death induced by acute and prolonged heat exposure. On the other hand, older animals with loss of function mutations in ceramide synthase (hyl-1, which converts sphingosine to ceramide, showed improved neuromuscular function and stress response with age. This phenotype was dependent on sphk-1. Together, our data show that loss of sphingosine kinase contributes to poor animal health span, suggesting that sphingolipid signaling may be important for healthy neuronal function and animal stress response during aging.

Time-dependent effects of neuropeptide Y infusion in the paraventricular hypothalamus on ingestive and associated behaviors in rats

NARCIS (Netherlands)

van Dijk, G; Strubbe, JH

In this study the role of neuropeptide Y (NPY) in the paraventricular nucleus of the hypothalamus (PVN) in the daily regulation of feeding, drinking, locomotor activity, and nestbox occupation was investigated. These behaviors were recorded during and after bilateral infusion of NPY into the PVN of

Regulator of G protein signaling-12 modulates the dopamine transporter in ventral striatum and locomotor responses to psychostimulants.

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Gross, Joshua D; Kaski, Shane W; Schroer, Adam B; Wix, Kimberley A; Siderovski, David P; Setola, Vincent

2018-02-01

Regulators of G protein signaling are proteins that accelerate the termination of effector stimulation after G protein-coupled receptor activation. Many regulators of G protein signaling proteins are highly expressed in the brain and therefore considered potential drug discovery targets for central nervous system pathologies; for example, here we show that RGS12 is highly expressed in microdissected mouse ventral striatum. Given a role for the ventral striatum in psychostimulant-induced locomotor activity, we tested whether Rgs12 genetic ablation affected behavioral responses to amphetamine and cocaine. RGS12 loss significantly decreased hyperlocomotion to lower doses of both amphetamine and cocaine; however, other outcomes of administration (sensitization and conditioned place preference) were unaffected, suggesting that RGS12 does not function in support of the rewarding properties of these psychostimulants. To test whether observed response changes upon RGS12 loss were caused by changes to dopamine transporter expression and/or function, we prepared crude membranes from the brains of wild-type and RGS12-null mice and measured dopamine transporter-selective [ 3 H]WIN 35428 binding, revealing an increase in dopamine transporter levels in the ventral-but not dorsal-striatum of RGS12-null mice. To address dopamine transporter function, we prepared striatal synaptosomes and measured [ 3 H]dopamine uptake. Consistent with increased [ 3 H]WIN 35428 binding, dopamine transporter-specific [ 3 H]dopamine uptake in RGS12-null ventral striatal synaptosomes was found to be increased. Decreased amphetamine-induced locomotor activity and increased [ 3 H]WIN 35428 binding were recapitulated with an independent RGS12-null mouse strain. Thus, we propose that RGS12 regulates dopamine transporter expression and function in the ventral striatum, affecting amphetamine- and cocaine-induced increases in dopamine levels that specifically elicit acute hyperlocomotor responses.

Δ9-tetrahydrocannabinol (Δ9-THC) administration after neonatal exposure to phencyclidine potentiates schizophrenia-related behavioral phenotypes in mice.

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Rodríguez, Guadalupe; Neugebauer, Nichole M; Yao, Katherine Lan; Meltzer, Herbert Y; Csernansky, John G; Dong, Hongxin

2017-08-01

The clinical onset of schizophrenia often coincides with cannabis use in adolescents and young adults. However, the neurobiological consequences of this co-morbidity are not well understood. In this study, we examined the effects of Δ9-THC exposure during early adulthood on schizophrenia-related behaviors using a developmental mouse model of schizophrenia. Phencyclidine (PCP) or saline was administered once in neonatal mice (at P7; 10mg/kg). In turn, Δ9-THC or saline was administered sub-acutely later in life to cohorts of animals who had received either PCP or saline (P55-80, 5mg/kg). Mice who were administered PCP alone displayed behavioral changes in the Morris water waze (MWM) and pre-pulse inhibition (PPI) task paradigm that were consistent with schizophrenia-related phenotypes, but not in the locomotor activity or novel object recognition (NOR) task paradigms. Mice who were administered PCP and then received Δ9-THC later in life displayed behavioral changes in the locomotor activity paradigm (pschizophrenia-related phenotype, as well as potentiated changes in the NOR (pschizophrenia-related behavioral phenotypes induced by neonatal exposure to PCP in mice. Copyright © 2017 Elsevier Inc. All rights reserved.

mGluR5-antagonist mediated reversal of elevated stereotyped, repetitive behaviors in the VPA model of autism.

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Mili V Mehta

Full Text Available Autism spectrum disorders (ASD are highly disabling developmental disorders with a population prevalence of 1-3%. Despite a strong genetic etiology, there are no current therapeutic options that target the core symptoms of ASD. Emerging evidence suggests that dysfunction of glutamatergic signaling, in particular through metabotropic glutamate receptor 5 (mGluR5 receptors, may contribute to phenotypic deficits and may be appropriate targets for pharmacologic intervention. This study assessed the therapeutic potential of 2-methyl-6-phenylethyl-pyrididine (MPEP, an mGluR5-receptor antagonist, on repetitive and anxiety-like behaviors in the valproic acid (VPA mouse model of autism. Mice were exposed prenatally on day E13 to VPA and assessed for repetitive self-grooming and marble burying behaviors as adults. Anxiety-like behavior and locomotor activity were measured in an open-field. VPA-exposed mice displayed increased repetitive and anxiety-like behaviors, consistent with previously published results. Across both marble burying and self-grooming assays, MPEP significantly reduced repetitive behaviors in VPA-treated mice, but had no effect on locomotor activity. These results are consistent with emerging preclinical literature that mGluR5-antagonists may have therapeutic efficacy for core symptoms of autism.

Using a Split-belt Treadmill to Evaluate Generalization of Human Locomotor Adaptation.

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Vasudevan, Erin V L; Hamzey, Rami J; Kirk, Eileen M

2017-08-23

Understanding the mechanisms underlying locomotor learning helps researchers and clinicians optimize gait retraining as part of motor rehabilitation. However, studying human locomotor learning can be challenging. During infancy and childhood, the neuromuscular system is quite immature, and it is unlikely that locomotor learning during early stages of development is governed by the same mechanisms as in adulthood. By the time humans reach maturity, they are so proficient at walking that it is difficult to come up with a sufficiently novel task to study de novo locomotor learning. The split-belt treadmill, which has two belts that can drive each leg at a different speed, enables the study of both short- (i.e., immediate) and long-term (i.e., over minutes-days; a form of motor learning) gait modifications in response to a novel change in the walking environment. Individuals can easily be screened for previous exposure to the split-belt treadmill, thus ensuring that all experimental participants have no (or equivalent) prior experience. This paper describes a typical split-belt treadmill adaptation protocol that incorporates testing methods to quantify locomotor learning and generalization of this learning to other walking contexts. A discussion of important considerations for designing split-belt treadmill experiments follows, including factors like treadmill belt speeds, rest breaks, and distractors. Additionally, potential but understudied confounding variables (e.g., arm movements, prior experience) are considered in the discussion.

Role of the agranular insular cortex in contextual control over cocaine-seeking behavior in rats.

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Arguello, Amy A; Wang, Rong; Lyons, Carey M; Higginbotham, Jessica A; Hodges, Matthew A; Fuchs, Rita A

2017-08-01

Environmental stimulus control over drug relapse requires the retrieval of context-response-cocaine associations, maintained in long-term memory through active reconsolidation processes. Identifying the neural substrates of these phenomena is important from a drug addiction treatment perspective. The present study evaluated whether the agranular insular cortex (AI) plays a role in drug context-induced cocaine-seeking behavior and cocaine memory reconsolidation. Rats were trained to lever press for cocaine infusions in a distinctive context, followed by extinction training in a different context. Rats in experiment 1 received bilateral microinfusions of vehicle or a GABA agonist cocktail (baclofen and muscimol (BM)) into the AI or the overlying somatosensory cortex (SSJ, anatomical control region) immediately before a test of drug-seeking behavior (i.e., non-reinforced lever presses) in the previously cocaine-paired context. The effects of these manipulations on locomotor activity were also assessed in a novel context. Rats in experiment 2 received vehicle or BM into the AI after a 15-min reexposure to the cocaine-paired context, intended to reactivate context-response-cocaine memories and initiate their reconsolidation. The effects of these manipulations on drug context-induced cocaine-seeking behavior were assessed 72 h later. BM-induced pharmacological inactivation of the AI, but not the SSJ, attenuated drug context-induced reinstatement of cocaine-seeking behavior without altering locomotor activity. Conversely, AI inactivation after memory reactivation failed to impair subsequent drug-seeking behavior and thus cocaine memory reconsolidation. These findings suggest that the AI is a critical element of the neural circuitry that mediates contextual control over cocaine-seeking behavior.

Activation of dopamine receptors in the nucleus accumbens promotes sucrose-reinforced cued approach behavior

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Saleem M. Nicola

2016-07-01

Full Text Available Dopamine receptor activation in the nucleus accumbens (NAc promotes vigorous environmentally-cued food-seeking in hungry rats. Rats fed ad libitum, however, respond to fewer food-predictive cues, particularly when the value of food reward is low. Here, we investigated whether this difference could be due to differences in the degree of dopamine receptor activation in the NAc. First, we observed that although rats given ad libitum access to chow in their home cages approached a food receptacle in response to reward-predictive cues, the number of such approaches declined as animals accumulated food rewards. Intriguingly, cued approach to food occurred in clusters, with several cued responses followed by successive non-responses. This pattern suggested that behavior was dictated by transitions between two states, responsive and non-responsive. Injection of D1 or D2 dopamine receptor agonists into the NAc dose-dependently increased cue responding by promoting transitions to the responsive state and by preventing transitions to the non-responsive state. In contrast, antagonists of either D1 or D2 receptors promoted long bouts of non-responding by inducing transitions to the non-responsive state and by preventing transitions to the responsive state. Moreover, locomotor behavior during the inter-trial interval was correlated with the responsive state, and was also increased by dopamine receptor agonists. These results suggest that activation of NAc dopamine receptors plays an important role in regulating the probability of approach to food under conditions of normative satiety.

Sherlock Holmes and the Curious Case of the Human Locomotor Central Pattern Generator.

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Klarner, Taryn; Zehr, E Paul

2018-03-14

Evidence first described in reduced animal models over 100 years ago led to deductions about the control of locomotion through spinal locomotor central pattern generating (CPG) networks. These discoveries in nature were contemporaneous with another form of deductive reasoning found in popular culture-that of Arthur Conan Doyle's detective "Sherlock Holmes". Since the invasive methods used in reduced non-human animal preparations are not amenable to study in humans, we are left instead with deducing from other measures and observations. Using the deductive reasoning approach of Sherlock Holmes as a metaphor for framing research into human CPGs, we speculate and weigh the evidence that should be observable in humans based on knowledge from other species. This review summarizes indirect inference to assess "observable evidence" of pattern generating activity which leads to the logical deduction of CPG contributions to arm and leg activity during locomotion in humans. The question of where a CPG may be housed in the human nervous system remains incompletely resolved at this time. Ongoing understanding, elaboration and application of functioning locomotor CPGs in humans is important for gait rehabilitation strategies in those with neurological injuries.

Comprehensive behavioral analysis of voltage-gated calcium channel beta-anchoring and -regulatory protein knockout mice

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Nakao, Akito; Miki, Takafumi; Shoji, Hirotaka; Nishi, Miyuki; Takeshima, Hiroshi; Miyakawa, Tsuyoshi; Mori, Yasuo

2015-01-01

Calcium (Ca2+) influx through voltage-gated Ca2+ channels (VGCCs) induces numerous intracellular events such as neuronal excitability, neurotransmitter release, synaptic plasticity, and gene regulation. It has been shown that genes related to Ca2+ signaling, such as the CACNA1C, CACNB2, and CACNA1I genes that encode VGCC subunits, are associated with schizophrenia and other psychiatric disorders. Recently, VGCC beta-anchoring and -regulatory protein (BARP) was identified as a novel regulator of VGCC activity via the interaction of VGCC β subunits. To examine the role of the BARP in higher brain functions, we generated BARP knockout (KO) mice and conducted a comprehensive battery of behavioral tests. BARP KO mice exhibited greatly reduced locomotor activity, as evidenced by decreased vertical activity, stereotypic counts in the open field test, and activity level in the home cage, and longer latency to complete a session in spontaneous T-maze alteration test, which reached “study-wide significance.” Acoustic startle response was also reduced in the mutants. Interestingly, they showed multiple behavioral phenotypes that are seemingly opposite to those seen in the mouse models of schizophrenia and its related disorders, including increased working memory, flexibility, prepulse inhibition, and social interaction, and decreased locomotor activity, though many of these phenotypes are statistically weak and require further replications. These results demonstrate that BARP is involved in the regulation of locomotor activity and, possibly, emotionality. The possibility was also suggested that BARP KO mice may serve as a unique tool for investigating the pathogenesis/pathophysiology of schizophrenia and related disorders. Further evaluation of the molecular and physiological phenotypes of the mutant mice would provide new insights into the role of BARP in higher brain functions. PMID:26136667

The glucagon-like peptide 1 analogue Exendin-4 attenuates the nicotine-induced locomotor stimulation, accumbal dopamine release, conditioned place preference as well as the expression of locomotor sensitization in mice.

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Emil Egecioglu

Full Text Available The gastrointestinal peptide glucagon-like peptide 1 (GLP-1 is known to regulate consummatory behavior and is released in response to nutrient ingestion. Analogues of this peptide recently emerged as novel pharmacotherapies for treatment of type II diabetes since they reduce gastric emptying, glucagon secretion as well as enhance glucose-dependent insulin secretion. The findings that GLP-1 targets reward related areas including mesolimbic dopamine areas indicate that the physiological role of GLP-1 extends beyond food intake and glucose homeostasis control to include reward regulation. The present series of experiments was therefore designed to investigate the effects of the GLP-1 receptor agonist, Exendin-4 (Ex4, on established nicotine-induced effects on the mesolimbic dopamine system in mice. Specifically, we show that treatment with Ex4, at a dose with no effect per se, attenuate nicotine-induced locomotor stimulation, accumbal dopamine release as well as the expression of conditioned place preference in mice. In accordance, Ex4 also blocks nicotine-induced expression of locomotor sensitization in mice. Given that development of nicotine addiction largely depends on the effects of nicotine on the mesolimbic dopamine system these findings indicate that the GLP-1 receptor may be a potential target for the development of novel treatment strategies for nicotine cessations in humans.

Tolerance and sensitization to inhaled 1,1,1-trichloroethane in mice: results from open-field behavior and a functional observational battery.

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Bowen, Scott E; Balster, Robert L

2006-05-01

1,1,1-Trichloroethane (TCE), a representative abused solvent, has well described acute behavioral effects in animals. Much less is known about repeated high-concentration exposures as would be encountered in inhalant abusers. Tolerance has been demonstrated in some, but not all, studies with TCE while sensitization has also been seen with other abused solvents. The present study was designed to further characterize changes in the effects of repeated exposure to TCE on a variety of mouse behaviors. Mice were tested using locomotor activity as well as a functional observational battery (FOB) both before and after a regimen of daily exposures to various concentrations of TCE. The initial locomotor effects of acute 30-min exposures to TCE were biphasic with concentration-dependent increases in activity at lower concentrations and decreases observed at higher concentrations. The profile of acute effects as measured by the FOB included changes in posture, decreased arousal, disturbances in gait, delayed righting reflexes, and decreased sensorimotor reactivity. Animals were then divided into five groups and exposed 30 min/day to either air or one of four concentrations of TCE (2,000, 6,000, 10,000, or 13,300 ppm) for 15 consecutive days. The TCE concentration used primarily affected the magnitude of change, not whether tolerance or sensitization occurred. Tolerance developed on the measures of forelimb grip strength, inverted screen, and number of rears. Conversely, sensitization developed to measures of locomotor activity. Depending on the behavioral measure, both tolerance and sensitization can occur in mice with repeated exposure to TCE. Both of these phenomena are characteristic of drugs of abuse.

Behavioral effects of antiepileptic drugs in rats: Are the effects on mood and behavior detectable in open-field test?

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Zimcikova, Eva; Simko, Julius; Karesova, Iva; Kremlacek, Jan; Malakova, Jana

2017-11-01

Behavioral side effects of antiepileptic drugs (AEDs) are common including both positive and negative effects on mood, anxiety, depression, and psychosis. We aimed to evaluate behavioral patterns in rats after administration of lamotrigine, levetiracetam, phenytoin, topiramate, carbamazepine, gabapentin, pregabalin, and zonisamide. The open-field test was performed and locomotion, rearing, grooming, central latency and defecation were recorded over a 5min interval for each rat (8 rats in each group receiving AED and 16 controls). Kruskal-Wallis nonparametric test or ANOVA were used to assess differences among the groups. The experimental groups did not differ in latency to enter the center compartment, neither in the decline of locomotor activity in the 1st and the 5th minute of the observation, nor in number of rears. Significant differences among groups were observed in the total number of lines crossed, grooming, as well in the number of fecal pellets. Locomotor activity was significantly increased in lamotrigine, if compared with gabapentin and pregabalin (ANOVA; p <0.05). Rats exposed to topiramate displayed a significantly increased number of grooming (when compared to pregabalin: p<0.01). Defecation (the number of fecal pellets) significantly increased in the gabapentin and carbamazepine group. There are significant differences between AEDs in terms of their behavioral profile. It is of great importance to evaluate these effects in clinical practice to bring more clear insight into these positive or negative side effects of AEDs. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Drosophila male sex peptide inhibits siesta sleep and promotes locomotor activity in the post-mated female.

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Isaac, R Elwyn; Li, Chenxi; Leedale, Amy E; Shirras, Alan D

2010-01-07

Quiescence, or a sleep-like state, is a common and important feature of the daily lives of animals from both invertebrate and vertebrate taxa, suggesting that sleep appeared early in animal evolution. Recently, Drosophila melanogaster has been shown to be a relevant and powerful model for the genetic analysis of sleep behaviour. The sleep architecture of D. melanogaster is sexually dimorphic, with females sleeping much less than males during day-time, presumably because reproductive success requires greater foraging activity by the female as well as the search for egg-laying sites. However, this loss of sleep and increase in locomotor activity will heighten the risk for the female from environmental and predator hazards. In this study, we show that virgin females can minimize this risk by behaving like males, with an extended afternoon 'siesta'. Copulation results in the female losing 70 per cent of day-time sleep and becoming more active. This behaviour lasts for at least 8 days after copulation and is abolished if the mating males lack sex peptide (SP), normally present in the seminal fluid. Our results suggest that SP is the molecular switch that promotes wakefulness in the post-mated female, a change of behaviour compatible with increased foraging and egg-laying activity. The stress resulting from SP-dependent sleep deprivation might be an important contribution to the toxic side-effects of male accessory gland products that are known to reduce lifespan in post-mated females.

Reducing prefrontal gamma-aminobutyric acid activity induces cognitive, behavioral, and dopaminergic abnormalities that resemble schizophrenia.

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Enomoto, Takeshi; Tse, Maric T; Floresco, Stan B

2011-03-01

Perturbations in gamma-aminobutyric acid (GABA)-related markers have been reported in the prefrontal cortex of schizophrenic patients. However, a preclinical assessment of how suppression of prefrontal cortex GABA activity may reflect behavioral and cognitive pathologies observed in schizophrenia is forthcoming. We assessed the effects of pharmacologic blockade of prefrontal cortex GABA(A) receptors in rats on executive functions and other behaviors related to schizophrenia, as well as neural activity of midbrain dopamine neurons. Blockade of prefrontal cortex GABA(A) receptors with bicuculline (12.5-50 ng) did not affect working memory accuracy but did increase response latencies, resembling speed of processing deficits observed in schizophrenia. Prefrontal cortex GABA(A) blockade did not impede simple discrimination or reversal learning but did impair set-shifting in a manner dependent on when these treatments were given. Reducing GABA activity before the set-shift impaired the ability to acquire a novel strategy, whereas treatment before the initial discrimination increased perseveration during the shift. Latent inhibition was unaffected by bicuculline infusions before the preexposure/conditioning phases, suggesting that reduced prefrontal cortex GABA activity does not impair "learned irrelevance." GABA(A) blockade increased locomotor activity and showed synergic effects with a subthreshold dose of amphetamine. Furthermore, reducing medial prefrontal cortex GABA activity selectively increased phasic burst firing of ventral tegmental area dopamine neurons, without altering the their overall population activity. These results suggest that prefrontal cortex GABA hypofunction may be a key contributing factor to deficits in speed of processing, cognitive flexibility, and enhanced phasic dopamine activity observed in schizophrenia. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Locomotor circumvention strategies are altered by stroke: I. Obstacle clearance.

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Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

2017-06-15

Functional locomotion requires the ability to adapt to environmental challenges such as the presence of stationary or moving obstacles. Difficulties in obstacle circumvention often lead to restricted community ambulation in individuals with stroke. The objective of this study was to contrast obstacle circumvention strategies between post-stroke (n = 12) and healthy individuals (n = 12) performing locomotor and perceptuomotor (joystick navigation) tasks with different obstacle approaches. Participants walked and navigated with a joystick towards a central target, in a virtual environment simulating a large room, while avoiding an obstacle that either remained stationary at the pre-determined point of intersection or moved from head-on or diagonally 30° left/right. The outcome measures included dynamic clearance (DC), instantaneous distance from obstacle at crossing (IDC), number of collisions and preferred side of circumvention. These measures were compared between groups (stroke vs. healthy), obstacle parameter (stationary vs. moving head-on) and direction of approach (left/paretic vs. right/non-paretic). DC was significantly larger when circumventing a moving obstacle that approached head-on as compared to a stationary obstacle for both groups during both tasks, while not significantly different in either diagonal approach in either group. IDC was smaller in the stroke group while walking and larger in both groups during joystick navigation when avoiding moving as compared to stationary obstacle. IDC was significantly larger in the stroke group compared to controls for diagonal approaches during walking, wherein two different strategies emerged amongst individuals with stroke: circumventing to the same (V same n = 6) or opposite (V opp n = 4) side of obstacle approach. This behavior was not seen in the perceptuomotor task, wherein post-stroke participants circumvented to opposite side of the obstacle approach as seen in healthy participants. In the

Locomotor Tests Predict Community Mobility in Children and Youth with Cerebral Palsy

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Ferland, Chantale; Moffet, Helene; Maltais, Desiree

2012-01-01

Ambulatory children and youth with cerebral palsy have limitations in locomotor capacities and in community mobility. The ability of three locomotor tests to predict community mobility in this population (N = 49, 27 boys, 6-16 years old) was examined. The tests were a level ground walking test, the 6-min-Walk-Test (6MWT), and two tests of advanced…

Ankle voluntary movement enhancement following robotic-assisted locomotor training in spinal cord injury.

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Varoqui, Deborah; Niu, Xun; Mirbagheri, Mehdi M

2014-03-31

In incomplete spinal cord injury (iSCI), sensorimotor impairments result in severe limitations to ambulation. To improve walking capacity, physical therapies using robotic-assisted locomotor devices, such as the Lokomat, have been developed. Following locomotor training, an improvement in gait capabilities-characterized by increases in the over-ground walking speed and endurance-is generally observed in patients. To better understand the mechanisms underlying these improvements, we studied the effects of Lokomat training on impaired ankle voluntary movement, known to be an important limiting factor in gait for iSCI patients. Fifteen chronic iSCI subjects performed twelve 1-hour sessions of Lokomat training over the course of a month. The voluntary movement was qualified by measuring active range of motion, maximal velocity peak and trajectory smoothness for the spastic ankle during a movement from full plantar-flexion (PF) to full dorsi-flexion (DF) at the patient's maximum speed. Dorsi- and plantar-flexor muscle strength was quantified by isometric maximal voluntary contraction (MVC). Clinical assessments were also performed using the Timed Up and Go (TUG), the 10-meter walk (10MWT) and the 6-minute walk (6MWT) tests. All evaluations were performed both before and after the training and were compared to a control group of fifteen iSCI patients. After the Lokomat training, the active range of motion, the maximal velocity, and the movement smoothness were significantly improved in the voluntary movement. Patients also exhibited an improvement in the MVC for their ankle dorsi- and plantar-flexor muscles. In terms of functional activity, we observed an enhancement in the mobility (TUG) and the over-ground gait velocity (10MWT) with training. Correlation tests indicated a significant relationship between ankle voluntary movement performance and the walking clinical assessments. The improvements of the kinematic and kinetic parameters of the ankle voluntary movement

Apomorphine effects on frog locomotor behavior

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Chu, Joanne; Wilczynski, Walter

2007-01-01

The neuroanatomical pathways of the DA systems have been shown to be largely conserved across many vertebrate taxa. It is less certain whether the structural similarities seen between mammals and amphibians reflect a similar functional homology. DA is well known for its role in facilitating motor behaviors in mammals. We examined whether a similar role for DA exists in amphibians using the Northern Leopard Frog (Rana pipiens). We investigated the effects of the nonspecific DA agonist, apomorp...

Muscle fiber type distribution in climbing Hawaiian gobioid fishes: ontogeny and correlations with locomotor performance.

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Cediel, Roberto A; Blob, Richard W; Schrank, Gordon D; Plourde, Robert C; Schoenfuss, Heiko L

2008-01-01

Three species of Hawaiian amphidromous gobioid fishes are remarkable in their ability to climb waterfalls up to several hundred meters tall. Juvenile Lentipes concolor and Awaous guamensis climb using rapid bursts of axial undulation, whereas juvenile Sicyopterus stimpsoni climb using much slower movements, alternately attaching oral and pelvic sucking disks to the substrate during prolonged bouts of several cycles. Based on these differing climbing styles, we hypothesized that propulsive musculature in juvenile L. concolor and A. guamensis would be dominated by white muscle fibers, whereas S. stimpsoni would exhibit a greater proportion of red muscle fibers than other climbing species. We further predicted that, because adults of these species shift from climbing to burst swimming as their main locomotor behavior, muscle from adult fish of all three species would be dominated by white fibers. To test these hypotheses, we used ATPase assays to evaluate muscle fiber type distribution in Hawaiian climbing gobies for three anatomical regions (midbody, anal, and tail). Axial musculature was dominated by white muscle fibers in juveniles of all three species, but juvenile S. stimpsoni had a significantly greater proportion of red fibers than the other two species. Fiber type proportions of adult fishes did not differ significantly from those of juveniles. Thus, muscle fiber type proportions in juveniles appear to help accommodate differences in locomotor demands among these species, indicating that they overcome the common challenge of waterfall climbing through both diverse behaviors and physiological specializations.

Motor hypertonia and lack of locomotor coordination in mutant mice lacking DSCAM.

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Lemieux, Maxime; Laflamme, Olivier D; Thiry, Louise; Boulanger-Piette, Antoine; Frenette, Jérôme; Bretzner, Frédéric

2016-03-01

Down syndrome cell adherence molecule (DSCAM) contributes to the normal establishment and maintenance of neural circuits. Whereas there is abundant literature regarding the role of DSCAM in the neural patterning of the mammalian retina, less is known about motor circuits. Recently, DSCAM mutation has been shown to impair bilateral motor coordination during respiration, thus causing death at birth. DSCAM mutants that survive through adulthood display a lack of locomotor endurance and coordination in the rotarod test, thus suggesting that the DSCAM mutation impairs motor control. We investigated the motor and locomotor functions of DSCAM(2J) mutant mice through a combination of anatomical, kinematic, force, and electromyographic recordings. With respect to wild-type mice, DSCAM(2J) mice displayed a longer swing phase with a limb hyperflexion at the expense of a shorter stance phase during locomotion. Furthermore, electromyographic activity in the flexor and extensor muscles was increased and coactivated over 20% of the step cycle over a wide range of walking speeds. In contrast to wild-type mice, which used lateral walk and trot at walking speed, DSCAM(2J) mice used preferentially less coordinated gaits, such as out-of-phase walk and pace. The neuromuscular junction and the contractile properties of muscles, as well as their muscle spindles, were normal, and no signs of motor rigidity or spasticity were observed during passive limb movements. Our study demonstrates that the DSCAM mutation induces dystonic hypertonia and a disruption of locomotor gaits. Copyright © 2016 the American Physiological Society.

Ebselen protects against behavioral and biochemical toxicities induced by 3-nitropropionic acid in rats: correlations between motor coordination, reactive species levels, and succinate dehydrogenase activity.

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Wilhelm, Ethel A; Bortolatto, Cristiani F; Jesse, Cristiano R; Luchese, Cristiane

2014-12-01

The protective effect of ebselen was investigated against 3-nitropropionic acid (3-NP)-induced behavioral and biochemical toxicities in rats. Ebselen (10 or 25 mg/kg, intragastrically) was administered to rats 30 min before 3-NP (20 mg/kg, intraperitoneally) once a day for a period of 4 days. Locomotor activity, motor coordination, and body weight gain were determined. The striatal content of reactive oxygen species (ROS), reduced glutathione (GSH), ascorbic acid (AA), and protein carbonyl as well as catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST) activities was determined 24 h after the last dose of 3-NP. Na(+)/ K(+)-ATPase, succinate dehydrogenase (SDH), and δ-aminolevulinic dehydratase (δ-ALA-D) activities were also determined. The results demonstrated that ebselen at a dose of 25 mg/kg, but not at 10 mg/kg, protected against (1) a decrease in locomotor activity, motor coordination impairment, and body weight loss; (2) striatal oxidative damage, which was characterized by an increase in ROS levels, protein carbonyl content, and GR activity, an inhibition of CAT and GPx activities, and a decrease in GSH levels; and (3) an inhibition of SDH and Na(+)/K(+)-ATPase activities, induced by 3-NP. GST activity and AA levels were not modified by ebselen or 3-NP. Ebselen was not effective against the inhibition of δ-ALA-D activity induced by 3-NP. The results revealed a significant correlation between SDH activity and ROS levels, and SDH activity and latency to fall (rotarod test). The present study highlighted the protective effect of ebselen against 3-NP-induced toxicity in rats.

Investigating the form-function interface in African apes: Relationships between principal moments of area and positional behaviors in femoral and humeral diaphyses.

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Carlson, Kristian J

2005-07-01

Investigations of cross-sectional geometry in nonhuman primate limb bones typically attribute shape ratios to qualitative behavioral characterizations, e.g., leaper, slow climber, brachiator, or terrestrial vs. arboreal quadruped. Quantitative positional behavioral data, however, have yet to be used in a rigorous evaluation of such shape-behavior connections. African apes represent an ideal population for such an investigation because their relatedness minimizes phylogenetic inertia, they exhibit diverse behavioral repertoires, and their locomotor behaviors are known from multiple studies. Cross-sectional data from femoral and humeral diaphyses were collected for 222 wild-shot specimens, encompassing Pan paniscus and all commonly recognized African ape subspecies. Digital representations of diaphyseal cross sections were acquired via computed tomography at three locations per diaphysis. Locomotor behaviors were pooled broadly into arboreal and terrestrial categories, then partitioned into quadrupedal walking, quadrumanous climbing, scrambling, and suspensory categories. Sex-specific taxonomic differences in ratios of principal moments of area (PMA) were statistically significant more often in the femoral diaphysis than the humeral diaphysis. While it appears difficult to relate a measure of shape (e.g., PMA ratio) to individual locomotor modes, general locomotor differences (e.g., percentage arboreal vs. terrestrial locomotion) are discerned more easily. As percentage of arboreal locomotion for a group increases, average cross sections appear more circular. Associations between PMA ratio and specific locomotor behaviors are less straightforward. Individual behaviors that integrate eccentric limb positions (e.g., arboreal scrambling) may not engender more circular cross sections than behaviors that incorporate repetitive sagittal movements (e.g., quadrupedal walking) in a straightforward manner. (c) 2004 Wiley-Liss, Inc

Chronic metals ingestion by prairie voles produces sex-specific deficits in social behavior: an animal model of autism.

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Curtis, J Thomas; Hood, Amber N; Chen, Yue; Cobb, George P; Wallace, David R

2010-11-12

We examined the effects of chronic metals ingestion on social behavior in the normally highly social prairie vole to test the hypothesis that metals may interact with central dopamine systems to produce the social withdrawal characteristic of autism. Relative to water-treated controls, 10 weeks of chronic ingestion of either Hg(++) or Cd(++) via drinking water significantly reduced social contact by male voles when they were given a choice between isolation or contact with an unfamiliar same-sex conspecific. The effects of metals ingestion were specific to males: no effects of metals exposure were seen in females. Metals ingestion did not alter behavior of males allowed to choose between isolation or their familiar cage-mates, rather than strangers. We also examined the possibility that metals ingestion affects central dopamine functioning by testing the voles' locomotor responses to peripheral administration of amphetamine. As with the social behavior, we found a sex-specific effect of metals on amphetamine responses. Males that consumed Hg(++) did not increase their locomotor activity in response to amphetamine, whereas similarly treated females and males that ingested only water significantly increased their locomotor activities. Thus, an ecologically relevant stimulus, metals ingestion, produced two of the hallmark characteristics of autism - social avoidance and a male-oriented bias. These results suggest that metals exposure may contribute to the development of autism, possibly by interacting with central dopamine function, and support the use of prairie voles as a model organism in which to study autism. (c) 2010 Elsevier B.V. All rights reserved.

Low doses of ivermectin cause sensory and locomotor disorders in dung beetles

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Verdú, José R.; Cortez, Vieyle; Ortiz, Antonio J.; González-Rodríguez, Estela; Martinez-Pinna, Juan; Lumaret, Jean-Pierre; Lobo, Jorge M.; Numa, Catherine; Sánchez-Piñero, Francisco

2015-09-01

Ivermectin is a veterinary pharmaceutical generally used to control the ecto- and endoparasites of livestock, but its use has resulted in adverse effects on coprophilous insects, causing population decline and biodiversity loss. There is currently no information regarding the direct effects of ivermectin on dung beetle physiology and behaviour. Here, based on electroantennography and spontaneous muscle force tests, we show sub-lethal disorders caused by ivermectin in sensory and locomotor systems of Scarabaeus cicatricosus, a key dung beetle species in Mediterranean ecosystems. Our findings show that ivermectin decreases the olfactory and locomotor capacity of dung beetles, preventing them from performing basic biological activities. These effects are observed at concentrations lower than those usually measured in the dung of treated livestock. Taking into account that ivermectin acts on both glutamate-gated and GABA-gated chloride ion channels of nerve and muscle cells, we predict that ivermectin’s effects at the physiological level could influence many members of the dung pat community. The results indicate that the decline of dung beetle populations could be related to the harmful effects of chemical contamination in the dung.

Locomotor Muscle Fatigue Does Not Alter Oxygen Uptake Kinetics during High-Intensity Exercise.

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Hopker, James G; Caporaso, Giuseppe; Azzalin, Andrea; Carpenter, Roger; Marcora, Samuele M

2016-01-01

The [Formula: see text] slow component ([Formula: see text]) that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre-fatigue condition) or rest for 33 min (control condition) according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-s maximal sprints at a fixed pedaling cadence of 90 rev·min -1 . Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE) were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and [Formula: see text] determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue ( P = 0.03), the [Formula: see text] was not significantly different between the pre-fatigue (464 ± 301 mL·min -1 ) and the control (556 ± 223 mL·min -1 ) condition ( P = 0.50). Blood lactate response was not significantly different between conditions ( P = 0.48) but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition ( P locomotor muscle fatigue does not significantly alter the [Formula: see text] kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the [Formula: see text] is strongly associated with locomotor muscle fatigue.

Potential contributions of training intensity on locomotor performance in individuals with chronic stroke.

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Holleran, Carey L; Rodriguez, Kelly S; Echauz, Anthony; Leech, Kristan A; Hornby, T George

2015-04-01

Many interventions can improve walking ability of individuals with stroke, although the training parameters that maximize recovery are not clear. For example, the contribution of training intensity has not been well established and may contribute to the efficacy of many locomotor interventions. The purpose of this preliminary study was to evaluate the effects of locomotor training intensity on walking outcomes in individuals with gait deficits poststroke. Using a randomized cross-over design, 12 participants with chronic stroke (>6-month duration) performed either high-intensity (70%-80% of heart rate reserve; n = 6) or low-intensity (30%-40% heart rate reserve; n = 6) locomotor training for 12 or fewer sessions over 4 to 5 weeks. Four weeks following completion, the alternate training intervention was performed. Training intensity was manipulated by adding loads or applying resistance during walking, with similar speeds, durations, and amount of stepping practice between conditions. Greater increases in 6-Minute Walk Test performance were observed following high-intensity training compared with low-intensity training. A significant interaction of intensity and order was also observed for 6-Minute Walk Test and peak treadmill speed, with the largest changes in those who performed high-intensity training first. Moderate correlations were observed between locomotor outcomes and measures of training intensity. This study provides the first evidence that the intensity of locomotor practice may be an important independent determinant of walking outcomes poststroke. In the clinical setting, the intensity of locomotor training can be manipulated in many ways, although this represents only 1 parameter to consider.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A90).

Locomotor muscle fatigue does not alter oxygen uptake kinetics during high-intensity exercise

Directory of Open Access Journals (Sweden)

James Hopker

2016-10-01

Full Text Available The slow component (VO2sc that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre fatigue condition or rest for 33 minutes (control condition according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-second maximal sprints at a fixed pedaling cadence of 90 rev·min-1. Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and VO2max determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue (P = 0.03, the VO2sc was not significantly different between the pre fatigue (464 ± 301 mL·min-1 and the control (556 ± 223 mL·min-1 condition (P = 0.50. Blood lactate response was not significantly different between conditions (P = 0.48 but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition (P < 0.01 suggesting higher muscle recruitment. These results demonstrate experimentally that locomotor muscle fatigue does not significantly alter the VO2 kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the VO2sc is strongly associated with locomotor muscle fatigue.

Balance and ambulation improvements in individuals with chronic incomplete spinal cord injury using locomotor training-based rehabilitation.

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Harkema, Susan J; Schmidt-Read, Mary; Lorenz, Douglas J; Edgerton, V Reggie; Behrman, Andrea L

2012-09-01

To evaluate the effects of intensive locomotor training on balance and ambulatory function at enrollment and discharge during outpatient rehabilitation after incomplete SCI. Prospective observational cohort. Seven outpatient rehabilitation centers from the Christopher and Dana Reeve Foundation NeuroRecovery Network (NRN). Patients (N=196) with American Spinal Injury Association Impairment Scale (AIS) grade C or D SCI who received at least 20 locomotor training treatment sessions in the NRN. Intensive locomotor training, including step training using body-weight support and manual facilitation on a treadmill followed by overground assessment and community integration. Berg Balance Scale; Six-Minute Walk Test; 10-Meter Walk Test. Outcome measures at enrollment showed high variability between patients with AIS grades C and D. Significant improvement from enrollment to final evaluation was observed in balance and walking measures for patients with AIS grades C and D. The magnitude of improvement significantly differed between AIS groups for all measures. Time since SCI was not associated significantly with outcome measures at enrollment, but was related inversely to levels of improvement. Significant variability in baseline values of functional outcome measures is evident after SCI in individuals with AIS grades C and D and significant functional recovery can continue to occur even years after injury when provided with locomotor training. These results indicate that rehabilitation, which provides intensive activity-based therapy, can result in functional improvements in individuals with chronic incomplete SCI. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Optimizing learning of a locomotor task: amplifying errors as needed.

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Marchal-Crespo, Laura; López-Olóriz, Jorge; Jaeger, Lukas; Riener, Robert

2014-01-01

Research on motor learning has emphasized that errors drive motor adaptation. Thereby, several researchers have proposed robotic training strategies that amplify movement errors rather than decrease them. In this study, the effect of different robotic training strategies that amplify errors on learning a complex locomotor task was investigated. The experiment was conducted with a one degree-of freedom robotic stepper (MARCOS). Subjects were requested to actively coordinate their legs in a desired gait-like pattern in order to track a Lissajous figure presented on a visual display. Learning with three different training strategies was evaluated: (i) No perturbation: the robot follows the subjects' movement without applying any perturbation, (ii) Error amplification: existing errors were amplified with repulsive forces proportional to errors, (iii) Noise disturbance: errors were evoked with a randomly-varying force disturbance. Results showed that training without perturbations was especially suitable for a subset of initially less-skilled subjects, while error amplification seemed to benefit more skilled subjects. Training with error amplification, however, limited transfer of learning. Random disturbing forces benefited learning and promoted transfer in all subjects, probably because it increased attention. These results suggest that learning a locomotor task can be optimized when errors are randomly evoked or amplified based on subjects' initial skill level.

A neurorobotic platform for locomotor prosthetic development in rats and mice

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von Zitzewitz, Joachim; Asboth, Leonie; Fumeaux, Nicolas; Hasse, Alexander; Baud, Laetitia; Vallery, Heike; Courtine, Grégoire

2016-04-01

Objectives. We aimed to develop a robotic interface capable of providing finely-tuned, multidirectional trunk assistance adjusted in real-time during unconstrained locomotion in rats and mice. Approach. We interfaced a large-scale robotic structure actuated in four degrees of freedom to exchangeable attachment modules exhibiting selective compliance along distinct directions. This combination allowed high-precision force and torque control in multiple directions over a large workspace. We next designed a neurorobotic platform wherein real-time kinematics and physiological signals directly adjust robotic actuation and prosthetic actions. We tested the performance of this platform in both rats and mice with spinal cord injury. Main Results. Kinematic analyses showed that the robotic interface did not impede locomotor movements of lightweight mice that walked freely along paths with changing directions and height profiles. Personalized trunk assistance instantly enabled coordinated locomotion in mice and rats with severe hindlimb motor deficits. Closed-loop control of robotic actuation based on ongoing movement features enabled real-time control of electromyographic activity in anti-gravity muscles during locomotion. Significance. This neurorobotic platform will support the study of the mechanisms underlying the therapeutic effects of locomotor prosthetics and rehabilitation using high-resolution genetic tools in rodent models.

Feedback and feedforward locomotor adaptations to ankle-foot load in people with incomplete spinal cord injury.

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Gordon, Keith E; Wu, Ming; Kahn, Jennifer H; Schmit, Brian D

2010-09-01

Humans with spinal cord injury (SCI) modulate locomotor output in response to limb load. Understanding the neural control mechanisms responsible for locomotor adaptation could provide a framework for selecting effective interventions. We quantified feedback and feedforward locomotor adaptations to limb load modulations in people with incomplete SCI. While subjects airstepped (stepping performed with kinematic assistance and 100% bodyweight support), a powered-orthosis created a dorisflexor torque during the "stance phase" of select steps producing highly controlled ankle-load perturbations. When given repetitive, stance phase ankle-load, the increase in hip extension work, 0.27 J/kg above baseline (no ankle-load airstepping), was greater than the response to ankle-load applied during a single step, 0.14 J/kg (P = 0.029). This finding suggests that, at the hip, subjects produced both feedforward and feedback locomotor modulations. We estimate that, at the hip, the locomotor response to repetitive ankle-load was modulated almost equally by ongoing feedback and feedforward adaptations. The majority of subjects also showed after-effects in hip kinetic patterns that lasted 3 min in response to repetitive loading, providing additional evidence of feedforward locomotor adaptations. The magnitude of the after-effect was proportional to the response to repetitive ankle-foot load (R(2) = 0.92). In contrast, increases in soleus EMG amplitude were not different during repetitive and single-step ankle-load exposure, suggesting that ankle locomotor modulations were predominately feedback-based. Although subjects made both feedback and feedforward locomotor adaptations to changes in ankle-load, between-subject variations suggest that walking function may be related to the ability to make feedforward adaptations.

Brief communication: Paleobiological inferences on the locomotor repertoire of extinct hominoids based on femoral neck cortical thickness: The fossil great ape hispanopithecus laietanus as a test-case study.

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Pina, Marta; Alba, David M; Almécija, Sergio; Fortuny, Josep; Moyà-Solà, Salvador

2012-09-01

The relationship between femoral neck superior and inferior cortical thickness in primates is related to locomotor behavior. This relationship has been employed to infer bipedalism in fossil hominins, although bipeds share the same pattern of generalized quadrupeds, where the superior cortex is thinner than the inferior one. In contrast, knuckle-walkers and specialized suspensory taxa display a more homogeneous distribution of cortical bone. These different patterns, probably related to the range of movement at the hip joint and concomitant differences in the load stresses at the femoral neck, are very promising for making locomotor inferences in extinct primates. To evaluate the utility of this feature in the fossil record, we relied on computed tomography applied to the femur of the Late Miocene hominoid Hispanopithecus laietanus as a test-case study. Both an orthograde body plan and orang-like suspensory adaptations had been previously documented for this taxon on different anatomical grounds, leading to the hypothesis that this fossil ape should display a modern ape-like distribution of femoral neck cortical thickness. This is confirmed by the results of this study, leading to the conclusion that Hispanopithecus represents the oldest evidence of a homogeneous cortical bone distribution in the hominoid fossil record. Our results therefore strengthen the utility of femoral neck cortical thickness for making paleobiological inferences on the locomotor repertoire of fossil primates. This feature would be particularly useful for assessing the degree of orthograde arboreal locomotor behaviors vs. terrestrial bipedalism in putative early hominins. Copyright © 2012 Wiley Periodicals, Inc.

V1 spinal neurons regulate the speed of vertebrate locomotor outputs

DEFF Research Database (Denmark)

Gosgnach, Simon; Lanuza, Guillermo M.; Butt, Simon J B

2006-01-01

The neuronal networks that generate vertebrate movements such as walking and swimming are embedded in the spinal cord1-3. These networks, which are referred to as central pattern generators (CPGs), are ideal systems for determining how ensembles of neurons generate simple behavioural outputs...... for inhibition in regulating the frequency of the locomotor CPG rhythm, and also suggest that V1 neurons may have an evolutionarily conserved role in controlling the speed of vertebrate locomotor movements....

Fluvoxamine moderates reduced voluntary activity following chronic dexamethasone infusion in mice via recovery of BDNF signal cascades.

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Terada, Kazuki; Izumo, Nobuo; Suzuki, Biora; Karube, Yoshiharu; Morikawa, Tomomi; Ishibashi, Yukiko; Kameyama, Toshiki; Chiba, Koji; Sasaki, Noriko; Iwata, Keiko; Matsuzaki, Hideo; Manabe, Takayuki

2014-04-01

Major depression is a complex disorder characterized by genetic and environmental interactions. Selective serotonin reuptake inhibitors (SSRIs) effectively treat depression. Neurogenesis following chronic antidepressant treatment activates brain derived neurotrophic factor (BDNF) signaling. In this study, we analyzed the effects of the SSRI fluvoxamine (Flu) on locomotor activity and forced-swim behavior using chronic dexamethasone (cDEX) infusions in mice, which engenders depression-like behavior. Infusion of cDEX decreased body weight and produced a trend towards lower locomotor activity during darkness. In the forced-swim test, cDEX-mice exhibited increased immobility times compared with mice administered saline. Flu treatment reversed decreased locomotor activity and mitigated forced-swim test immobility. Real-time polymerase chain reactions using brain RNA samples yielded significantly lower BDNF mRNA levels in cDEX-mice compared with the saline group. Endoplasmic reticulum stress-associated X-box binding protein-1 (XBP1) gene expression was lower in cDEX-mice compared with the saline group. However, marked expression of the XBP1 gene was observed in cDEX-mice treated with Flu compared with mice given saline and untreated cDEX-mice. Expression of 5-HT2A and Sigma-1 receptors decreased after cDEX infusion compared with the saline group, and these decreases normalized to control levels upon Flu treatment. Our results indicate that the Flu moderates reductions in voluntary activity following chronic dexamethasone infusions in mice via recovery of BDNF signal cascades. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intermittent long-wavelength red light increases the period of daily locomotor activity in mice

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Hughes Amanda M

2005-05-01

Full Text Available Abstract Background We observed that a dim, red light-emitting diode (LED triggered by activity increased the circadian periods of lab mice compared to constant darkness. It is known that the circadian period of rats increases when vigorous wheel-running triggers full-spectrum lighting; however, spectral sensitivity of photoreceptors in mice suggests little or no response to red light. Thus, we decided to test the following hypotheses: dim red light illumination triggered by activity (LEDfb increases the circadian period of mice compared to constant dark (DD; covering the LED prevents the effect on period; and DBA2/J mice have a different response to LEDfb than C57BL6/J mice. Methods The irradiance spectra of the LEDs were determined by spectrophotometer. Locomotor activity of C57BL/6J and DBA/2J mice was monitored by passive-infrared sensors and circadian period was calculated from the last 10 days under each light condition. For constant dark (DD, LEDs were switched off. For LED feedback (LEDfb, the red LED came on when the mouse was active and switched off seconds after activity stopped. For taped LED the red LED was switched on but covered with black tape. Single and multifactorial ANOVAs and post-hoc t-tests were done. Results The circadian period of mice was longer under LEDfb than under DD. Blocking the light eliminated the effect. There was no difference in period change in response to LEDfb between C57BL/6 and DBA/2 mice. Conclusion An increase in mouse circadian period due to dim far-red light (1 lux at 652 nm exposure was unexpected. Since blocking the light stopped the response, sound from the sensor's electronics was not the impetus of the response. The results suggest that red light as background illumination should be avoided, and indicator diodes on passive infrared motion sensors should be switched off.

Behavioral and genetic effects promoted by sleep deprivation in rats submitted to pilocarpine-induced status epilepticus.

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Matos, Gabriela; Ribeiro, Daniel A; Alvarenga, Tathiana A; Hirotsu, Camila; Scorza, Fulvio A; Le Sueur-Maluf, Luciana; Noguti, Juliana; Cavalheiro, Esper A; Tufik, Sergio; Andersen, Monica L

2012-05-02

The interaction between sleep deprivation and epilepsy has been well described in electrophysiological studies, but the mechanisms underlying this association remain unclear. The present study evaluated the effects of sleep deprivation on locomotor activity and genetic damage in the brains of rats treated with saline or pilocarpine-induced status epilepticus (SE). After 50 days of pilocarpine or saline treatment, both groups were assigned randomly to total sleep deprivation (TSD) for 6 h, paradoxical sleep deprivation (PSD) for 24 h, or be kept in their home cages. Locomotor activity was assessed with the open field test followed by resection of brain for quantification of genetic damage by the single cell gel electrophoresis (comet) assay. Status epilepticus induced significant hyperactivity in the open field test and caused genetic damage in the brain. Sleep deprivation procedures (TSD and PSD) did not affect locomotor activity in epileptic or healthy rats, but resulted in significant DNA damage in brain cells. Although PSD had this effect in both vehicle and epileptic groups, TSD caused DNA damage only in epileptic rats. In conclusion, our results revealed that, despite a lack of behavioral effects of sleep deprivation, TSD and PSD induced genetic damage in rats submitted to pilocarpine-induced SE. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Buoyancy under control: underwater locomotor performance in a deep diving seabird suggests respiratory strategies for reducing foraging effort.

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Timothée R Cook

Full Text Available BACKGROUND: Because they have air stored in many body compartments, diving seabirds are expected to exhibit efficient behavioural strategies for reducing costs related to buoyancy control. We study the underwater locomotor activity of a deep-diving species from the Cormorant family (Kerguelen shag and report locomotor adjustments to the change of buoyancy with depth. METHODOLOGY/PRINCIPAL FINDINGS: Using accelerometers, we show that during both the descent and ascent phases of dives, shags modelled their acceleration and stroking activity on the natural variation of buoyancy with depth. For example, during the descent phase, birds increased swim speed with depth. But in parallel, and with a decay constant similar to the one in the equation explaining the decrease of buoyancy with depth, they decreased foot-stroke frequency exponentially, a behaviour that enables birds to reduce oxygen consumption. During ascent, birds also reduced locomotor cost by ascending passively. We considered the depth at which they started gliding as a proxy to their depth of neutral buoyancy. This depth increased with maximum dive depth. As an explanation for this, we propose that shags adjust their buoyancy to depth by varying the amount of respiratory air they dive with. CONCLUSIONS/SIGNIFICANCE: Calculations based on known values of stored body oxygen volumes and on deep-diving metabolic rates in avian divers suggest that the variations of volume of respiratory oxygen associated with a respiration mediated buoyancy control only influence aerobic dive duration moderately. Therefore, we propose that an advantage in cormorants--as in other families of diving seabirds--of respiratory air volume adjustment upon diving could be related less to increasing time of submergence, through an increased volume of body oxygen stores, than to reducing the locomotor costs of buoyancy control.

Role of the brain dopaminergic and opioid system in the regulation of "child's" (maternal bonding) behavior of newborn albino rats.

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Stovolosov, I S; Dubynin, V A; Kamensky, A A

2011-01-01

Administration of D(2) receptor antagonist clebopride in a dose not affecting locomotor activity was followed by a decrease in maternal bonding behavior of 10-day-old and 15-day-old albino rat pups. D(1) receptor antagonist SCH23390 had a stimulatory effect only on the behavior of 10-day-old newborns. Opioid peptide β-casomorphin-7 abolished the effect of clebopride in rat pups of the older age group.

Double blind comparative study of piroxicam and indomethacin in acute locomotor affections linked with sports activity.

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Commandre, F

1983-01-01

181 patients suffering from acute locomotor affections linked with sports activities were included in a multi-center study. The indications most frequently seen were sprains and tendinitis. 92 patients received piroxicam in a daily dosage of 4 capsules (40 mg) during the first two days, then 20 mg during the following days. 89 patients received a daily dose of indomethacin in a daily dose of 6 capsules (150 mg) for the first two days, and then 100 mg daily thereafter. Treatment lasted from 5 to seven days. Efficacy was judged to be very good or good in 89% of the patients treated with piroxicam against 76% of those treated with indomethacin, a statistically significant difference. Tolerance was also judged better with piroxicam. 4 patients suffered side effects with piroxicam, of which one stopped treatment after the second administration due to allergic reaction. 18 patients treated with indomethacin suffered from side effects, of which 5 stopped the treatment. In total, the use of piroxicam seems particularly interesting in sports medicine in comparison with indomethacin.

Objective and quantitative equilibriometric evaluation of individual locomotor behaviour in schizophrenia: Translational and clinical implications.

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Haralanov, Svetlozar; Haralanova, Evelina; Milushev, Emil; Shkodrova, Diana; Claussen, Claus-Frenz

2018-04-17

Psychiatry is the only medical specialty that lacks clinically applicable biomarkers for objective evaluation of the existing pathology at a single-patient level. On the basis of an original translational equilibriometric method for evaluation of movement patterns, we have introduced in the everyday clinical practice of psychiatry an easy-to-perform computerized objective quantification of the individual locomotor behaviour during execution of the Unterberger stepping test. For the last 20 years, we have gradually collected a large database of more than 1000 schizophrenic patients, their relatives, and matched psychiatric, neurological, and healthy controls via cross-sectional and longitudinal investigations. Comparative analyses revealed transdiagnostic locomotor similarities among schizophrenic patients, high-risk schizotaxic individuals, and neurological patients with multiple sclerosis and cerebellar ataxia, thus suggesting common underlying brain mechanisms. In parallel, intradiagnostic dissimilarities were revealed, which allow to separate out subclinical locomotor subgroups within the diagnostic categories. Prototypical qualitative (dysmetric and ataxic) locomotor abnormalities in schizophrenic patients were differentiated from 2 atypical quantitative ones, manifested as either hypolocomotion or hyperlocomotion. Theoretical analyses suggested that these 3 subtypes of locomotor abnormalities could be conceived as objectively measurable biomarkers of 3 schizophrenic subgroups with dissimilar brain mechanisms, which require different treatment strategies. Analogies with the prominent role of locomotor measures in some well-known animal models of mental disorders advocate for a promising objective translational research in the so far over-subjective field of psychiatry. Distinctions among prototypical, atypical, and diagnostic biomarkers, as well as between neuromotor and psychomotor locomotor abnormalities, are discussed. Conclusions are drawn about the

Locomotor recovery after spinal cord contusion injury in rats is improved by spontaneous exercise

NARCIS (Netherlands)

Gispen, W.H.; Meeteren, N.L. van; Eggers, L.; Lankhorst, A.J.; Hamers, F.P.

2003-01-01

We have recently shown that enriched environment (EE) housing significantly enhances locomotor recovery following spinal cord contusion injury (SCI) in rats. As the type and intensity of locomotor training with EE housing are rather poorly characterized, we decided to compare the effectiveness of EE

Synthetic trehalose dicorynomycolate (S-TDCM). Behavioral effects and radioprotection

International Nuclear Information System (INIS)

Landauer, M.R.; Mcchesney, D.G.; Ledney, G.D.

1997-01-01

This study evaluated synthetic trehalose dicorynomycolate (S-TDCM), an immunomodulator, for its survival enhancing capacity and behavioral toxicity in B6D2F1 female mice. In survival experiments, mice were administered S-TDCM (25-400 μg/mouse i.p.) 20-24 hr before 5.6 Gy mixed-field fission-neutron irradiation (n) and γ-photon irradiation. The 30-day survival rates for mice treated with 100-400 μg/mouse S-TDCM were significantly enhanced compared to controls. Toxicity of S-TDCM was measured in nonirradiated mice by locomotor activity, food intake, water consumption, and alterations in body weight. A dose-dependent decrease was noted in all behavioral measures in mice treated with S-TDCM. Doses of 100 and 200 μg/mouse S-TDCM significantly reduced motor activity beginning 12 hr postinjection with recovery by 24 hr. A dose of 400 μg/mouse significantly decreased activity within the first 4 hr after administration and returned to control levels by 32 hr following injection. Food and water intake were significantly depressed at doses of 200 and 400 μg/mouse on the day following drug administration, and were recovered in 24 hr. Body weight was significantly decreased in the 200 μg/mouse group for 2 days and in the 400 μg/mouse group for 4 days following injection. A dose of 100 μg/mouse effectively enhanced survival after fission-neutron irradiation with no adverse effect on food consumption, water intake, or body weight and a minimal, short-term effect on locomotor activity. (author)

Assaying locomotor, learning, and memory deficits in Drosophila models of neurodegeneration.

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Ali, Yousuf O; Escala, Wilfredo; Ruan, Kai; Zhai, R Grace

2011-03-11

Advances in genetic methods have enabled the study of genes involved in human neurodegenerative diseases using Drosophila as a model system. Most of these diseases, including Alzheimer's, Parkinson's and Huntington's disease are characterized by age-dependent deterioration in learning and memory functions and movement coordination. Here we use behavioral assays, including the negative geotaxis assay and the aversive phototaxic suppression assay (APS assay), to show that some of the behavior characteristics associated with human neurodegeneration can be recapitulated in flies. In the negative geotaxis assay, the natural tendency of flies to move against gravity when agitated is utilized to study genes or conditions that may hinder locomotor capacities. In the APS assay, the learning and memory functions are tested in positively-phototactic flies trained to associate light with aversive bitter taste and hence avoid this otherwise natural tendency to move toward light. Testing these trained flies 6 hours post-training is used to assess memory functions. Using these assays, the contribution of any genetic or environmental factors toward developing neurodegeneration can be easily studied in flies.

Crocin improved locomotor function and mechanical behavior in the rat model of contused spinal cord injury through decreasing calcitonin gene related peptide (CGRP).

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Karami, Masoume; Bathaie, S Zahra; Tiraihi, Taqi; Habibi-Rezaei, Mehran; Arabkheradmand, Jalil; Faghihzadeh, Soghrat

2013-12-15

Various approaches have been offered to alleviate chronic pain resulting from spinal cord injuries (SCIs). Application of herbs and natural products, with potentially lower adverse effects, to cure diseases has been recommended in both traditional and modern medicines. Here, the effect of crocin on chronic pain induced by spinal cord contusion was investigated in an animal model. Female Wistar rats were randomly divided into five groups (5 rats in each); three groups were contused at the L1 level. One group was treated with crocin (150mg/kg) two weeks after spinal cord injury; the second group, control, was treated with vehicle only; and the third group was treated with ketoprofen. Two normal groups were also considered with or without crocin treatment. The mechanical behavioral test, the locomotor recovery test and the thermal behavioral test were applied weekly to evaluate the injury and recovery of rats. Significant improvements (plocomotor recovery tests were seen in the rats treated with crocin. Thermal behavioral test did not show any significant changes due to crocin treatment. Plasma concentration of calcitonin-gene related peptide (CGRP) changed from 780.2±2.3 to 1140.3±4.5pg/ml due to SCI and reached 789.1±2.7pg/ml after crocin treatment. These changes were significant at the level of p<0.05. The present study shows the beneficial effects of crocin treatment on chronic pain induced by SCI, through decreasing CGRP as an important mediator of inflammation and pain. Copyright © 2013 Elsevier GmbH. All rights reserved.

EphA4 defines a class of excitatory locomotor-related interneurons

DEFF Research Database (Denmark)

Butt, S. J B; Lundfald, Line; Kiehn, Ole

2005-01-01

of these interneurons provide direct excitation to ipsilateral motor neurons as determined by spike-triggered averaging of the local ventral root DC trace. Our findings substantiate the role of EphA4-positive interneurons as significant components of the ipsilateral locomotor network and describe a group of putative...... of the role of these cells in the network. One such marker is the EphA4 axon guidance receptor. EphA4-null mice display an abnormal rabbit-like hopping gait that is thought to be the result of synchronization of the normally alternating, bilateral locomotor network via aberrant crossed connections....... In this study, we have performed whole-cell patch clamp on EphA4-positive interneurons in the flexor region (L2) of the locomotor network. We provide evidence that although EphA4 positive interneurons are not entirely a homogeneous population, most of them fire in a rhythmic manner. Moreover, a subset...

Peripheral afferent mechanisms underlying acupuncture inhibition of cocaine behavioral effects in rats.

Directory of Open Access Journals (Sweden)

Seol Ah Kim

Full Text Available Administration of cocaine increases locomotor activity by enhancing dopamine transmission. To explore the peripheral mechanisms underlying acupuncture treatment for drug addiction, we developed a novel mechanical acupuncture instrument (MAI for objective mechanical stimulation. The aim of this study was to evaluate whether acupuncture inhibition of cocaine-induced locomotor activity is mediated through specific peripheral nerves, the afferents from superficial or deep tissues, or specific groups of nerve fibers. Mechanical stimulation of acupuncture point HT7 with MAI suppressed cocaine-induced locomotor activity in a stimulus time-dependent manner, which was blocked by severing the ulnar nerve or by local anesthesia. Suppression of cocaine-induced locomotor activity was elicited after HT7 stimulation at frequencies of either 50 (for Meissner corpuscles or 200 (for Pacinian corpuscles Hz and was not affected by block of C/Aδ-fibers in the ulnar nerve with resiniferatoxin, nor generated by direct stimulation of C/Aδ-fiber afferents with capsaicin. These findings suggest that HT7 inhibition of cocaine-induced locomotor activity is mediated by A-fiber activation of ulnar nerve that originates in superficial and deep tissue.

Application of the Copenhagen Soccer Test in high-level women players - locomotor activities, physiological response and sprint performance.

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Bendiksen, Mads; Pettersen, Svein Arne; Ingebrigtsen, Jørgen; Randers, Morten B; Brito, João; Mohr, Magni; Bangsbo, Jens; Krustrup, Peter

2013-12-01

We evaluated the physiological response, sprint performance and technical ability in various phases of the Copenhagen Soccer Test for Women (CSTw) and investigated whether the locomotor activities of the CSTw were comparable to competitive match-play (CM). Physiological measurements and physical/technical assessments were performed during CSTw for eleven Norwegian high-level women soccer players. The activity pattern during CSTw and CM was monitored using the ZXY tracking system. No differences were observed between CSTw and CM with regards to total distance covered (10093±94 and 9674±191m), high intensity running (1278±67 and 1193±115m) or sprinting (422±55 and 372±46m) (p>.05). During CSTw, average HR was 85±2%HRmax with 35±2% playing time >90%HRmax. Blood lactate increased (ptest. Blood glucose was 5.4±0.3mM at rest and remained unaltered during CSTw. Sprint performance (2×20m) decreased (plocomotor activities during CSTw were comparable to that of high-level competitive match-play. The physiological demands of the CSTw were high, with no changes in heart rate, blood lactate or technical performance during the test, but a lowered sprint performance towards the end of the test. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of BDNF receptor antagonist on the severity of physical and psychological dependence, morphine-induced locomotor sensitization and the ventral tegmental area-nucleus accumbens BDNF levels in morphine- dependent and withdrawn rats.

Science.gov (United States)

Khalil-Khalili, Masoumeh; Rashidy-Pour, Ali; Bandegi, Ahmad Reza; Yousefi, Behpoor; Jorjani, Hassan; Miladi-Gorji, Hossein

2018-03-06

This study examined the effects of systemic administration of the TrkB receptor antagonist (ANA-12) on the severity of physical and psychological dependence and morphine-induced locomotor sensitization, the ventral tegmental area (VTA)-nucleus accumbens (NAc) BDNF levels in morphine-dependent and withdrawn rats. Rats were injected with bi-daily doses (10 mg/kg, at 12 h intervals) of morphine for 10 days. Then, rats were tested for naloxone-precipitated morphine withdrawal signs, the anxiety (the elevated plus maze-EPM) after the last morphine injection and injection of ANA12 (ip). Also, morphine-induced locomotor sensitization was evaluated after morphine challenge followed by an injection of ANA-12 in morphine-withdrawn rats. The VTA-NAc BDNF levels were assessed in morphine-dependent and withdrawn rats. The overall Gellert-Holtzman score was significantly higher in morphine-dependent rats receiving ANA-12 than in those receiving saline. Also, the percentage of time spent in the open arms in control and morphine-dependent rats receiving ANA-12 were higher compared to the Cont/Sal and D/Sal rats, respectively. There was no significant difference in the locomotor activity and the VTA-NAc BDNF levels between D/Sal/morphine and D/ANA-12/morphine groups after morphine withdrawal. We conclude that the systemic administration of ANA-12 exacerbates the severity of physical dependence on morphine and partially attenuates the anxiety-like behavior in morphine-dependent rats. However, ANA-12 did not affect morphine-induced locomotor sensitization and the VTA-NAc BDNF levels in morphine-dependent and withdrawn rats. Copyright © 2017 Elsevier B.V. All rights reserved.

Visuo-locomotor control in persons with spinal cord injury in a manual or power wheelchair for direction change and obstacle circumvention.

Science.gov (United States)

Charette, Caroline; Routhier, François; McFadyen, Bradford J

2017-09-01

Many individuals, such as persons with spinal cord injury (SCI), rely on wheeled locomotion involving manual (MWC) or power (PWC) wheelchairs to navigate their environments. Yet, visuo-locomotor control underlying WC navigation in experienced users is not well understood. The objective of this study was to compare the visuo-locomotor control between MWC and PWC in individuals with SCI while changing direction and circumventing an obstacle. Participants with SCI using a MWC (n = 12, 38.5 ± 10.7 years) or a PWC (n = 10, 47.8 ± 8.6 years) were asked to maneuver their chair straight ahead, while changing direction 45° to the right, and while circumventing an obstacle to the right, all at self-selected speeds. Speed, minimal clearance, point of deviation, temporal body and WC coordination, relative timing of segment rotations and visual behavior were analyzed. There was no main effect of group for speed, clearance and point of deviation. During direction change, the head always led body and wheelchair reorientation while an "en bloc" strategy was used for circumventing obstacle for both groups. In straight-ahead locomotion, participants predominantly fixed their gaze on the end target. During direction change and obstacle circumvention, participants fixated more on the future path and the obstacle for both WC modes. Overall, specific gaze behavior depended on environmental demands. While MWC and PWC users adopt similar navigational strategies and visuo-locomotor coordination while changing direction and circumventing obstacle, there were some differences in the amount of head rotation that could be related to a counter-movement used more by PWC users.

Plasticity of locomotor sensorimotor interactions after peripheral and/or spinal lesions