Human umbilical cord mesenchymal stromal cells suppress MHC class II expression on rat vascular endothelium and prolong survival time of cardiac allograft

Science.gov (United States)

Qiu, Ying; Yun, Mark M; Han, Xia; Zhao, Ruidong; Zhou, Erxia; Yun, Sheng

2014-01-01

Background: Human umbilical cord mesenchymal stromal cells (UC-MSCs) have low immunogenicity and immune regulation. To investigate immunomodulatory effects of human UC-MSCs on MHC class II expression and allograft, we transplanted heart of transgenic rats with MHC class II expression on vascular endothelium. Methods: UC-MSCs were obtained from human umbilical cords and confirmed with flow cytometry analysis. Transgenic rat line was established using the construct of human MHC class II transactivator gene (CIITA) under mouse ICAM-2 promoter control. The induced MHC class II expression on transgenic rat vascular endothelial cells (VECs) was assessed with immunohistological staining. And the survival time of cardiac allograft was compared between the recipients with and without UC-MSC transfusion. Results: Flow cytometry confirmed that the human UC-MSCs were positive for CD29, CD44, CD73, CD90, CD105, CD271, and negative for CD34 and HLA-DR. Repeated infusion of human UC-MSCs reduced MHC class II expression on vascular endothelia of transplanted hearts, and increased survival time of allograft. The UC-MSCs increased regulatory cytokines IL10, transforming growth factor (TGF)-β1 and suppressed proinflammatory cytokines IL2 and IFN-γ in vivo. The UC-MSC culture supernatant had similar effects on cytokine expression, and decreased lymphocyte proliferation in vitro. Conclusions: Repeated transfusion of the human UC-MSCs reduced MHC class II expression on vascular endothelia and prolonged the survival time of rat cardiac allograft. PMID:25126177

The effect of chronic nitric oxide inhibition on vascular reactivity and blood pressure in pregnant rats

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Nilton Hideto Takiuti

1999-09-01

Full Text Available CONTEXT: The exact mechanism involved in changes in blood pressure and peripheral vascular resistance during pregnancy is unknown. OBJECTIVE:To evaluate the importance of endothelium-derivated relaxing factor (EDRF and its main component, nitric oxide, in blood pressure and vascular reactivity in pregnant rats. DESIGN: Clinical trial in experimentation animals. SETTING: University laboratory of Pharmacology. SAMPLE: Female Wistar rats with normal blood pressure, weight (152 to 227 grams and age (90 to 116 days. INTERVENTION: The rats were divided in to four groups: pregnant rats treated with L-NAME (13 rats; pregnant control rats (8 rats; virgin rats treated with L-NAME (10 rats; virgin control rats (12 rats. The vascular preparations and caudal blood pressure were obtained at the end of pregnancy, or after the administration of L-NAME in virgin rats. MAIN MEASUREMENTS: The caudal blood pressure and the vascular response to acetylcholine in pre-contracted aortic rings, both with and without endothelium, and the effect of nitric oxide inhibition, Nw-L-nitro-arginine methyl-ester (L-NAME, in pregnant and virgin rats. The L-NAME was administered in the drinking water over a 10-day period. RESULTS: The blood pressure decreased in pregnancy. Aortic rings of pregnant rats were more sensitive to acetylcholine than those of virgin rats. After L-NAME treatment, the blood pressure increased and relaxation was blocked in both groups. The fetal-placental unit weight of the L-NAME group was lower than that of the control group. CONCLUSION: Acetylcholine-induced vasorelaxation sensitivity was greater in pregnant rats and that blood pressure increased after L-NAME administration while the acetylcholine-induced vasorelaxation response was blocked.

Effects of hypothyroidism on vascular 125I-albumin permeation and blood flow in rats

International Nuclear Information System (INIS)

Tilton, R.G.; Pugliese, G.; Chang, K.; Speedy, A.; Province, M.A.; Kilo, C.; Williamson, J.R.

1989-01-01

Effects of hypothyroidism on vascular 125I-albumin permeation and on blood flow were assessed in multiple tissues of male Sprague-Dawley rats rendered hypothyroid by dietary supplementation with 0.5% (wt/wt) 2-thiouracil or by thyroidectomy. In both thiouracil-treated and thyroidectomized rats, body weights, kidney weight, arterial blood pressure, and pulse rate were decreased significantly v age-matched controls. After 10 to 12 weeks of thiouracil treatment, 125I-albumin permeation was increased significantly in the kidney, aorta, eye (anterior uvea, choroid, retina), skin, and new granulation tissue, remained unchanged in brain, sciatic nerve, and heart, and was decreased in forelimb skeletal muscle. A similar pattern was observed in thyroidectomized rats, except that increases in 125I-albumin permeation for all tissues were smaller than those observed in thiouracil-treated rats, and 125I-albumin permeation in retina did not differ from controls. In both thiouracil-treated and thyroidectomized rats, changes in blood flow (assessed with 15-microns, 85Sr-labeled microspheres) relative to the decrease in arterial blood pressure were indicative of a decrease in regional vascular resistance except in the choroid and in the kidney, in which vascular resistance was increased significantly. Glomerular filtration rate was decreased, but filtration fraction and urinary excretion of albumin remained unchanged by thiouracil treatment and thyroidectomy. These results indicate that vascular hemodynamics and endothelial cell barrier functional integrity are modulated in many different tissues by the thyroid. In view of the correspondence of hypothyroid- and diabetes-induced vascular permeability changes, these results raise the possibility that altered thyroid function in diabetes may play a role in the pathogenesis of diabetic vascular disease

Suppression of vascular smooth muscle cells' proliferation and ...

African Journals Online (AJOL)

This study aimed to determine the effects of valsartan on the proliferation and migration of isolated rat vascular smooth muscle cells (VSMCs) and the expression of phospho-p42/44 mitogen-activated protein kinase (MAPK) promoted by angiotensin II (Ang II). VSMCs from the rat thoracic aorta were cultured by ...

Vascular neuroeffector activity in the rat during pregnancy

International Nuclear Information System (INIS)

Hart, J.L.; Freas, W.; Muldoon, S.M.

1986-01-01

The activity of the vascular neuroeffector junction was examined in pregnant (PG) and non-pregnant (NPG) rats to determine if changes could account for the reported alterations in sympathetic control of the maternal circulation. Caudal and mesenteric arteries were removed from NPG and 19-21PG rats and prepared for isometric tension recording in Krebs-filled, 37 0 C tissue baths. At optimal passive tension frequency-response measurements were obtained with and without cocaine (10- 5 M), followed by norepinephrine (NE) and tyramine conc-response measurements. The densely innervated caudal artery developed more tension in response to NE, tyramine and transmural electrical stimulation than did the moderately innervated mesenteric artery. There were no significant differences in responses between vessels from NPG and PG rats, NE content, 3 H-NE accumulation, and effects of plasma on 3 H-NE accumulation of NPG and PG caudal arteries were also compared. The NE content of the NPG artery (8.61 +/- .61) was not different from that of the PG artery (9.97 +/- .71 μg/g). Also, NE accumulation was similar, and plasma inhibited 3 H-NE accumulation to the same extent. These results indicate that vascular neuroeffector functions of NE release, receptor sensitivity and uptake are not modified in the rat during pregnancy. Changes in sympathetic control of the circulation previously reported, therefore, are likely to be dependent on alterations at sites other than the neuroeffector junction

BAG3 promotes the phenotypic transformation of primary rat vascular smooth muscle cells via TRAIL.

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Fu, Yao; Chang, Ye; Chen, Shuang; Li, Yuan; Chen, Yintao; Sun, Guozhe; Yu, Shasha; Ye, Ning; Li, Chao; Sun, Yingxian

2018-05-01

Under normal physiological condition, the mature vascular smooth muscle cells (VSMCs) show differentiated phenotype. In response to various environmental stimuluses, VSMCs convert from the differentiated phenotype to dedifferentiated phenotype characterized by the increased ability of proliferation/migration and the reduction of contractile ability. The phenotypic transformation of VSMCs played an important role in atherosclerosis. Both Bcl-2-associated athanogene 3 (BAG3) and tumor necrosis factor-related apopt-osis inducing ligand (TRAIL) involved in apoptosis. The relationship between BAG3 and TRAIL and their effects the proliferation and migration in VSMCs are rarely reported. This study investigated the effects of BAG3 on the phenotypic modulation and the potential underlying mechanisms in primary rat VSMCs. Primary rat VSMCs were extracted and cultured in vitro. Cell proliferation was detected by cell counting, real-time cell analyzer (RTCA) and EdU incorporation. Cell migration was detected by wound healing, Transwell and RTCA. BAG3 and TRAIL were detected using real-time PCR and western blotting and the secreted proteins in the cultured media by dot blot. The expression of BAG3 increased with continued passages in cultured primary VSMCs. BAG3 promoted the proliferation and migration of primary rat VSMC in a time-dependent manner. BAG3 significantly increased the expression of TRAIL while had no effects on its receptors. TRAIL knockdown or blocking by neutralizing antibody inhibited the proliferation of VSMCs induced by BAG3. TRAIL knockdown exerted no obvious influence on the migration of VSMCs. Based on this study, we report for the first time that BAG3 was expressed in cultured primary rat VSMCs and the expression of BAG3 increased with continued passages. Furthermore, BAG3 promoted the proliferation of VSMCs via increasing the expression of TRAIL. In addition, we also demonstrated that BAG3 promoted the migration of VSMCs independent of TRAIL

Peculiarities of vascular tunic microstructure of the white rat eyeball under the effect of opioid.

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Mateshuk-Vatseba, Lesya; Pidvalna, Uliana; Kost, Andriy

2015-01-01

This article deals with determination of changes in the structural organization of vascular tunic of the eyeball under the effect of opioid. The study was carried out on 24 mature white male rats aged 3.0-4.5 months and 170-280 g weight. The research material included histological specimen and semi-thin sections of white rats' eyeball vascular tunic. For the histological study, microscopic sections of the eyeball were stained with Hematoxylin and Eosin, Heidenhain's Azan trichrome. Specimens were studied and photographed with microscope magnification: ×600, ×1000. The first signs of microstructure disorder in all parts of vascular tunic of the eyeball are noticeable after two weeks of nalbuphine injection to the white rats. During the next four weeks of the experiment, the pathological changes increase and are manifested by the swelling and polymorphonuclear infiltration of the iris, ciliary body, choroid and by deep destructive changes of eyeball hemomicrocirculatory bloodstream. Histological and ultramicroscopic studies of the white rats' eyeball vascular tunic after six weeks of nalbuphine injections showed deep destructive changes in the structure of all parts of vascular tunic. Our study demonstrated a negative effect of the prolonged injection of opioid in the experiment on the state of microstructural organization of the eyeball vascular tunic. Development of angiopathy is the triggering for occurrence of destructive changes in the eyeball under the effect of opioid.

Effects of hypothyroidism on vascular /sup 125/I-albumin permeation and blood flow in rats

Energy Technology Data Exchange (ETDEWEB)

Tilton, R.G.; Pugliese, G.; Chang, K.; Speedy, A.; Province, M.A.; Kilo, C.; Williamson, J.R.

1989-05-01

Effects of hypothyroidism on vascular 125I-albumin permeation and on blood flow were assessed in multiple tissues of male Sprague-Dawley rats rendered hypothyroid by dietary supplementation with 0.5% (wt/wt) 2-thiouracil or by thyroidectomy. In both thiouracil-treated and thyroidectomized rats, body weights, kidney weight, arterial blood pressure, and pulse rate were decreased significantly v age-matched controls. After 10 to 12 weeks of thiouracil treatment, 125I-albumin permeation was increased significantly in the kidney, aorta, eye (anterior uvea, choroid, retina), skin, and new granulation tissue, remained unchanged in brain, sciatic nerve, and heart, and was decreased in forelimb skeletal muscle. A similar pattern was observed in thyroidectomized rats, except that increases in 125I-albumin permeation for all tissues were smaller than those observed in thiouracil-treated rats, and 125I-albumin permeation in retina did not differ from controls. In both thiouracil-treated and thyroidectomized rats, changes in blood flow (assessed with 15-microns, 85Sr-labeled microspheres) relative to the decrease in arterial blood pressure were indicative of a decrease in regional vascular resistance except in the choroid and in the kidney, in which vascular resistance was increased significantly. Glomerular filtration rate was decreased, but filtration fraction and urinary excretion of albumin remained unchanged by thiouracil treatment and thyroidectomy. These results indicate that vascular hemodynamics and endothelial cell barrier functional integrity are modulated in many different tissues by the thyroid. In view of the correspondence of hypothyroid- and diabetes-induced vascular permeability changes, these results raise the possibility that altered thyroid function in diabetes may play a role in the pathogenesis of diabetic vascular disease.

Activation of the NLRP3 inflammasome induces vascular dysfunction in obese OLETF rats

International Nuclear Information System (INIS)

Liu, Penghao; Xie, Qihai; Wei, Tong; Chen, Yichen; Chen, Hong; Shen, Weili

2015-01-01

Objective: Obesity-induced vascular dysfunction is related to chronic low-grade systemic inflammation. Recent studies indicate that NLRP3, a multiprotein complex formed by NOD-like receptor (NLR) family members, is a key component mediating internal sterile inflammation, but the role in obesity-related vascular dysfunction is largely unknown. In the present study, we investigate whether NLRP3 activation is involved in vascular inflammation in obese Otsuka Long-Evans Tokushima Fatty rats (OLETF). Methods and results: Male OLETF with their control Long-Evans Tokushima Otsuka rats (LETO) were studied at 3 and 12 months of age. Aortic relaxation in response to acetylcholine decreased gradually with age in both strains, with early and persistent endothelium dysfunction in obese OLETF compared with age-matched LETO controls. These changes are associated with parallel changes of aortic endothelial nitric oxide synthase (eNOS) content, macrophage accumulation and intimal thickening. NLRP3 increased in OLETF rats compared to LETO. Consistent with inflammasome activation, the conversion of procaspase-1 to cleaved and activated forms as well as IL-1β markedly increased in OLETF rats. Additionally, we observed increased expression of dynamin-related protein-1 (Drp1) and decreased fusion-relative protein optic atropy-1(OPA1). Altered mitochondrial dynamics was associated with elevated oxidative stress level in OLETF aortas. Conclusions: These results demonstrate that obesity seems to accelerate endothelial dysfunction in OLETFs via the activation of NLRP3 and mitochondrial dysfunction. - Highlights: • NLRP3 is involved in obesity-induced vascular dysfunction. • Impaired mitochondrial dynamics may have been linked to mitochondrial defect and inflammasome activation. • Obesity seems to accelerate vascular dysfunction via NLRP3 activation and mitochondrial dysfunction.

Activation of the NLRP3 inflammasome induces vascular dysfunction in obese OLETF rats

Energy Technology Data Exchange (ETDEWEB)

Liu, Penghao [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Xie, Qihai [Department of Cardiology, Shanghai Jiading District Central Hospital, Shanghai (China); Wei, Tong [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Chen, Yichen [Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Chen, Hong, E-mail: hchen100@shsmu.edu.cn [Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Shen, Weili, E-mail: wlshen@sibs.ac.cn [State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension and Department of Hypertension, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

2015-12-04

Objective: Obesity-induced vascular dysfunction is related to chronic low-grade systemic inflammation. Recent studies indicate that NLRP3, a multiprotein complex formed by NOD-like receptor (NLR) family members, is a key component mediating internal sterile inflammation, but the role in obesity-related vascular dysfunction is largely unknown. In the present study, we investigate whether NLRP3 activation is involved in vascular inflammation in obese Otsuka Long-Evans Tokushima Fatty rats (OLETF). Methods and results: Male OLETF with their control Long-Evans Tokushima Otsuka rats (LETO) were studied at 3 and 12 months of age. Aortic relaxation in response to acetylcholine decreased gradually with age in both strains, with early and persistent endothelium dysfunction in obese OLETF compared with age-matched LETO controls. These changes are associated with parallel changes of aortic endothelial nitric oxide synthase (eNOS) content, macrophage accumulation and intimal thickening. NLRP3 increased in OLETF rats compared to LETO. Consistent with inflammasome activation, the conversion of procaspase-1 to cleaved and activated forms as well as IL-1β markedly increased in OLETF rats. Additionally, we observed increased expression of dynamin-related protein-1 (Drp1) and decreased fusion-relative protein optic atropy-1(OPA1). Altered mitochondrial dynamics was associated with elevated oxidative stress level in OLETF aortas. Conclusions: These results demonstrate that obesity seems to accelerate endothelial dysfunction in OLETFs via the activation of NLRP3 and mitochondrial dysfunction. - Highlights: • NLRP3 is involved in obesity-induced vascular dysfunction. • Impaired mitochondrial dynamics may have been linked to mitochondrial defect and inflammasome activation. • Obesity seems to accelerate vascular dysfunction via NLRP3 activation and mitochondrial dysfunction.

Ghrelin improves vascular autophagy in rats with vascular calcification.

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Xu, Mingming; Liu, Lin; Song, Chenfang; Chen, Wei; Gui, Shuyan

2017-06-15

This study aimed to investigate whether ghrelin ameliorated vascular calcification (VC) through improving autophagy. VC model was induced by nicotine plus vitamin D 3 in rats and β-glycerophosphate in vascular smooth muscle cell (VSMC). Calcium deposition was detected by von Kossa staining or alizarin red S staining. ALP activity was also detected. Western blot was used to assess the protein expression. Ghrelin treatment attenuated the elevation of calcium deposition and ALP activity in VC model both in vivo and in vitro. Interesting, the protein levels of autophagy markers, LC3 and beclin1 were significantly upregulated by ghrelin in VC model. An autophagy inhibitor, 3-methyladenine blocks the ameliorative effect of ghrelin on VC. Furthermore, protein expressions of phosphate-AMPK were increased by ghrelin treatment both in calcified aorta and VSMC. The effect of ghrelin on autophagy induction and VC attenuation was prevented by AMPK inhibitor, compound C. Our results suggested that ghrelin improved autophagy through AMPK activation, which was resulted in VC amelioration. These data maybe throw light on prevention and therapy of VC. Copyright © 2016 Elsevier Inc. All rights reserved.

Selective cyclooxygenase-1 inhibition improves collateral vascular reactivity in biliary cirrhotic rats

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Ching-Chih Chang

2013-10-01

Conclusion: There was no significant hemodynamic change and renal toxicity after acute administration of COX inhibitor in the FBDL-induced cirrhotic rats. Preincubation of selective COX-1, but not COX-2, inhibitor could enhance collateral vascular response to AVP, indicating that COX-1 plays a major role in the collateral vascular reactivity.

Quercetin Attenuates Vascular Calcification through Suppressed Oxidative Stress in Adenine-Induced Chronic Renal Failure Rats.

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Chang, Xue-Ying; Cui, Lei; Wang, Xing-Zhi; Zhang, Lei; Zhu, Dan; Zhou, Xiao-Rong; Hao, Li-Rong

2017-01-01

This study investigated whether quercetin could alleviate vascular calcification in experimental chronic renal failure rats induced by adenine. 32 adult male Wistar rats were randomly divided into 4 groups fed normal diet, normal diet with quercetin supplementation (25 mg/kg·BW/d), 0.75% adenine diet, or adenine diet with quercetin supplementation. All rats were sacrificed after 6 weeks of intervention. Serum renal functions biomarkers and oxidative stress biomarkers were measured and status of vascular calcification in aorta was assessed. Furthermore, the induced nitric oxide synthase (iNOS)/p38 mitogen activated protein kinase (p38MAPK) pathway was determined to explore the potential mechanism. Adenine successfully induced renal failure and vascular calcification in rat model. Quercetin supplementation reversed unfavorable changes of phosphorous, uric acid (UA) and creatinine levels, malonaldehyde (MDA) content, and superoxide dismutase (SOD) activity in serum and the increases of calcium and alkaline phosphatase (ALP) activity in the aorta ( P chronic renal failure rats, possibly through the modulation of oxidative stress and iNOs/p38MAPK pathway.

Quercetin Attenuates Vascular Calcification through Suppressed Oxidative Stress in Adenine-Induced Chronic Renal Failure Rats

Science.gov (United States)

Chang, Xue-ying; Cui, Lei; Wang, Xing-zhi; Zhang, Lei; Zhu, Dan

2017-01-01

Background This study investigated whether quercetin could alleviate vascular calcification in experimental chronic renal failure rats induced by adenine. Methods 32 adult male Wistar rats were randomly divided into 4 groups fed normal diet, normal diet with quercetin supplementation (25 mg/kg·BW/d), 0.75% adenine diet, or adenine diet with quercetin supplementation. All rats were sacrificed after 6 weeks of intervention. Serum renal functions biomarkers and oxidative stress biomarkers were measured and status of vascular calcification in aorta was assessed. Furthermore, the induced nitric oxide synthase (iNOS)/p38 mitogen activated protein kinase (p38MAPK) pathway was determined to explore the potential mechanism. Results Adenine successfully induced renal failure and vascular calcification in rat model. Quercetin supplementation reversed unfavorable changes of phosphorous, uric acid (UA) and creatinine levels, malonaldehyde (MDA) content, and superoxide dismutase (SOD) activity in serum and the increases of calcium and alkaline phosphatase (ALP) activity in the aorta (P chronic renal failure rats, possibly through the modulation of oxidative stress and iNOs/p38MAPK pathway. PMID:28691026

Dipeptidyl peptidase-4 inhibitor gemigliptin protects against vascular calcification in an experimental chronic kidney disease and vascular smooth muscle cells.

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Soon-Youn Choi

Full Text Available Although dipeptidyl peptidase-4 inhibitors, a class of antidiabetic drugs, have various pleiotropic effects, it remains undetermined whether gemigliptin has a beneficial effect on vascular calcification. Therefore, this study was performed to evaluate the effect of gemigliptin on vascular calcification in a rat model of adenine-induced chronic kidney disease and in cultured vascular smooth muscle cells. Gemigliptin attenuated calcification of abdominal aorta and expression of RUNX2 in adenine-induced chronic kidney disease rats. In cultured vascular smooth muscle cells, phosphate-induced increase in calcium content was reduced by gemigliptin. Gemigliptin reduced phosphate-induced PiT-1 mRNA expression, reactive oxygen species generation, and NADPH oxidase mRNA expression (p22phox and NOX4. The reduction of oxidative stress by gemigliptin was associated with the downregulation of phospho-PI3K/AKT expression. High phosphate increased the expression of frizzled-3 (FDZ3 and decreased the expression of dickkopf-related protein-1 (DKK-1 in the Wnt pathway. These changes were attenuated by gemigliptin treatment. Gemigliptin restored the decreased expression of vascular smooth muscle cells markers (α-SMA and SM22α and increased expression of osteogenic makers (CBFA1, OSX, E11, and SOST induced by phosphate. In conclusion, gemigliptin attenuated vascular calcification and osteogenic trans-differentiation in vascular smooth muscle cells via multiple steps including downregulation of PiT-1 expression and suppression of reactive oxygen species generation, phospho-PI3K/AKT, and the Wnt signaling pathway.

Hepatic oxidative stress, genotoxicity and vascular dysfunction in lean or obese zucker rats

DEFF Research Database (Denmark)

Løhr, Mille; Folkmann, Janne Kjærsgaard; Sheykhzade, Majid

2015-01-01

Metabolic syndrome is associated with increased risk of cardiovascular disease, which could be related to oxidative stress. Here, we investigated the associations between hepatic oxidative stress and vascular function in pressurized mesenteric arteries from lean and obese Zucker rats at 14, 24 an......-generated DNA damage despite substantial hepatic steatosis.......Metabolic syndrome is associated with increased risk of cardiovascular disease, which could be related to oxidative stress. Here, we investigated the associations between hepatic oxidative stress and vascular function in pressurized mesenteric arteries from lean and obese Zucker rats at 14, 24...... and 37 weeks of age. Obese Zucker rats had more hepatic fat accumulation than their lean counterparts. Nevertheless, the obese rats had unaltered age-related level of hepatic oxidatively damaged DNA in terms of formamidopyrimidine DNA glycosylase (FPG) or human oxoguanine DNA glycosylase (hOGG1...

Quercetin Attenuates Vascular Calcification through Suppressed Oxidative Stress in Adenine-Induced Chronic Renal Failure Rats

Directory of Open Access Journals (Sweden)

Xue-ying Chang

2017-01-01

Full Text Available Background. This study investigated whether quercetin could alleviate vascular calcification in experimental chronic renal failure rats induced by adenine. Methods. 32 adult male Wistar rats were randomly divided into 4 groups fed normal diet, normal diet with quercetin supplementation (25 mg/kg·BW/d, 0.75% adenine diet, or adenine diet with quercetin supplementation. All rats were sacrificed after 6 weeks of intervention. Serum renal functions biomarkers and oxidative stress biomarkers were measured and status of vascular calcification in aorta was assessed. Furthermore, the induced nitric oxide synthase (iNOS/p38 mitogen activated protein kinase (p38MAPK pathway was determined to explore the potential mechanism. Results. Adenine successfully induced renal failure and vascular calcification in rat model. Quercetin supplementation reversed unfavorable changes of phosphorous, uric acid (UA and creatinine levels, malonaldehyde (MDA content, and superoxide dismutase (SOD activity in serum and the increases of calcium and alkaline phosphatase (ALP activity in the aorta (P<0.05 and attenuated calcification and calcium accumulation in the medial layer of vasculature in histopathology. Western blot analysis showed that iNOS/p38MAPK pathway was normalized by the quercetin supplementation. Conclusions. Quercetin exerted a protective effect on vascular calcification in adenine-induced chronic renal failure rats, possibly through the modulation of oxidative stress and iNOs/p38MAPK pathway.

Roselle supplementation prevents nicotine-induced vascular endothelial dysfunction and remodelling in rats.

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Si, Lislivia Yiang-Nee; Kamisah, Yusof; Ramalingam, Anand; Lim, Yi Cheng; Budin, Siti Balkis; Zainalabidin, Satirah

2017-07-01

Vascular endothelial dysfunction (VED) plays an important role in the initiation of cardiovascular diseases. Roselle, enriched with antioxidants, demonstrates high potential in alleviating hypertension. This study was undertaken to investigate the effects of roselle supplementation of VED and remodelling in a rodent model with prolonged nicotine administration. Male Sprague-Dawley rats (n = 6 per group) were administered with 0.6 mg/kg nicotine for 28 days to induce VED. The rats were given either aqueous roselle (100 mg/kg) or normal saline orally 30 min prior to nicotine injection daily. One additional group of rats served as control. Thoracic aorta was isolated from rats to measure vascular reactivity, vascular remodelling and oxidative stress. Roselle significantly lowered aortic sensitivity to phenylephrine-induced vasoconstriction (Endo-(+) C max = 234.5 ± 3.9%, Endo-(-) C max = 247.6 ± 5.2%) compared with untreated nicotine group (Endo-(+) C max = 264.5 ± 6.9%, Endo-(-) C max = 276.5 ± 6.8%). Roselle also improved aortic response to endothelium-dependent vasodilator, acetylcholine (Endo-(+) R max = 73.2 ± 2.1%, Endo-(-) R max = 26.2 ± 0.8%) compared to nicotine group (Endo-(+) R max = 57.8 ± 1.7%, Endo-(-) R max = 20.9 ± 0.8%). In addition, roselle prevented an increase in intimal media thickness and elastic lamellae proliferation to preserve vascular architecture. Moreover, we also observed a significantly lowered degree of oxidative stress in parallel with increased antioxidant enzymes in aortic tissues of the roselle-treated group. This study demonstrated that roselle prevents VED and remodelling, and as such it has high nutraceutical value as supplement to prevent cardiovascular diseases.

Age-related memory decline is associated with vascular and microglial degeneration in aged rats.

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Zhang, Rong; Kadar, Tamar; Sirimanne, Ernest; MacGibbon, Alastair; Guan, Jian

2012-12-01

The hippocampus processes memory is an early target of aging-related biological and structural lesions, leading to memory decline. With absent neurodegeneration in the hippocampus, which identified in rodent model of normal aging the pathology underlying age-related memory impairment is not complete. The effective glial-vascular networks are the key for maintaining neuronal functions. The changes of glial cells and cerebral capillaries with age may contribute to memory decline. Thus we examined age associated changes in neurons, glial phenotypes and microvasculature in the hippocampus of aged rats with memory decline. Young adult (6 months) and aged (35 months) male rats (Fisher/Norway-Brown) were used. To evaluate memory, four days of acquisition phase of Morris water maze tasks were carried out in both age groups and followed by a probe trial 2 h after the acquisition. The brains were then collected for analysis using immunochemistry. The aged rats showed a delayed latency (pvascular and microglial degeneration with reduced vascular endothelial growth factor and elevated GFAP expression in the hippocampus. The data indicate the memory decline with age is associated with neuronal dysfunction, possibly due to impaired glial-vascular-neuronal networks, but not neuronal degeneration. Glial and vascular degeneration found in aged rats may represent early event of aging pathology prior to neuronal degeneration. Copyright © 2012 Elsevier B.V. All rights reserved.

CaMKII and MEK1/2 inhibition time-dependently modify inflammatory signaling in rat cerebral arteries during organ culture

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Waldsee, Roya; Eftekhari, Sajedeh; Ahnstedt, Hilda

2014-01-01

MKII) II and extracellular signal-regulated kinase1/2 (ERK1/2) on inflammatory mediators in rat cerebral arteries using organ culture as a method for inducing ischemic-like vascular wall changes. METHODS: Rat basilar arteries were cultured in serum-free medium for 0, 3, 6 or 24 hours in the presence...... of phosphorylated c-Jun N-terminal kinase and p-p38, as evaluated by immunohistochemistry. KN93 affected the increase in caspase-3 mRNA expression only when given at the start of incubation, while U0126 had an inhibitory effect when given up to six hours later. Tumor necrosis factor receptor 1 was elevated after...

Effect of nabumetone treatment on vascular responses of the thoracic aorta in rat experimental arthritis.

Science.gov (United States)

Ulker, S; Onal, A; Hatip, F B; Sürücü, A; Alkanat, M; Koşay, S; Evinç, A

2000-04-01

Nabumetone is a nonsteroidal anti-inflammatory (NSAI) drug which is known to cause less gastrointestinal damage than other NSAI drugs. This study was performed to evaluate whether nabumetone treatment might alter the vascular aberrations related to inflammation in a rat model of adjuvant-induced arthritis. Nabumetone treatment (120 or 240 mg x kg(-1) x day(-1), orally) was initiated on the 15th day of adjuvant inoculation and continued for 14 days. Arthritic lesions, vascular contractile and relaxant responses and gastroduodenal histopathological preparations were evaluated 29 days after adjuvant inoculation. The contractile responses of aortic rings to phenylephrine and KCl were increased in grade 2 arthritic rats. In grade 3 arthritis only the phenylephrine contractility was decreased. The relaxant responses to acetylcholine and sodium nitroprusside were decreased in grades 2 and 3. In healthy rats, nabumetone did not change the vascular responses. After treatment of arthritic rats with nabumetone, both the contractile and relaxant response of the aortic rings returned to normal, and arthritic score and paw swelling were reduced. Gastroduodenal histopathology did not show erosions or ulcers in any of the groups. In conclusion, nabumetone improved the systemic signs and vascular alterations in experimental arthritis without showing any gastrointestinal side effects. Copyright 2000 S. Karger AG, Basel.

Stress susceptibility as a determinant of endothelium-dependent vascular reactivity in rat mesenteric arteries.

NARCIS (Netherlands)

Riksen, N.P.; Ellenbroek, B.A.; Cools, A.R.; Siero, H.L.M.; Rongen, G.A.P.J.M.; Smits, B.W.; Russel, F.G.M.; Smits, P.

2003-01-01

In order to investigate the consequences of stress susceptibility on vascular function, the authors assessed the respective contributions of nitric oxide (NO), prostanoids, and endothelium-derived hyperpolarizing factor to the vascular tone in rats with a constitutionally determined high and low

Changes in vascular reactivity induced by acute hyperthyroidism in isolated rat aortae.

Science.gov (United States)

Honda, H; Iwata, T; Mochizuki, T; Kogo, H

2000-06-01

Hyperthyroidism was induced by subcutaneous injections of L-thyroxine (T(4)) (500 mg/kg/day) for 3 days in order to study whether adrenergic and muscarinic receptor-mediated vascular responses alter at an early stage of the disease. T(4) treatment was sufficient to induce a significant degree of thyroid weight loss, tachycardia, cardiac hypertrophy, and an elevation in serum T(4) levels. The tension of aortic ring preparations isolated from rats was measured isometrically to investigate the influence of acute hyperthyroidism. The contractions induced by norepinephrine (NE) were significantly suppressed in aortic rings from rats treated with T(4) compared with control rats. N(G)-nitro-L-arginine (L-NOARG), an inhibitor of nitric oxide synthase (NOS), significantly enhanced NE-induced contraction in aortic rings from both control and T(4)-treated rats, and the enhancement was greater in rats treated with T(4) than control rats. The relaxations induced by either acetylcholine (ACh) or sodium nitroprusside (SNP) were also significantly enhanced by T(4) treatment. L-NOARG abolished the relaxation induced by ACh in aortic rings from both control and T(4)-treated rats. L-NOARG shifted SNP-induced relaxation curves of aortic rings from those of control rats to the left, but not with rats treated with T(4). T(4) treatment showed no influence on the amount of endothelial NOS (eNOS) protein. These results suggest that vascular responses alter at an early stage of hyperthyroidism and that it may be due to a modification in the NO system which is independent from the amount of eNOS protein.

[Effects of Total Alkaloids of Harmaline on Learning and Memory in Vascular Dementia Rats].

Science.gov (United States)

Zhang, Xiao-shuang; Sun, Jian-ning; Yu, Hui-ling

2015-11-01

To investigate the effects of total alkaloids of harmaline on learning and memory in vascular dementia rats, and its mechanism. The model rats of vascular dementia were established with bilateral carotid artery ligation. After 30 days, the model rats were randomly divided into six groups: sham group, model group, nicergoline tablets 7 mg/kg group, and 25, 12.5 and 6.25 mg/kg dose groups of total alkaloids of harmaline, the rats were given medicine for 30 days. Learning and memory abilities were tested by Morris water maze, histomorphology in hippocampal CA1 area were observed by HE staining, BAX and BCL-2 protein expression in hippocampal CA1 area were detected by immunohistochemistry. Compared with model group, 25 mg/kg group of total alkaloids of harmaline shortened the incubation period in the third and fourth day significantly, 12.5 mg/kg group of total alkaloids of harmaline shortened the incubation period in the fourth day. 25 and 12.5 mg/kg groups of total alkaloids of harmaline significantly increased the times crossing the target. Total alkaloids of harmaline improved the neurons pathological changes of rat in the hippocampus CA1 area, 25 and 12.5 mg/kg of total alkaloids of harmaline downregulated the expression of apoptosis proteins BAX, upregulated the protein expression of BCL-2. Total alkaloids of harmaline can improve the learning and memory abilities in vascular dementia rats, which probably is related to inhibiting apoptosis of hippocampus cell.

Vascular smooth muscle cells exhibit a progressive loss of rigidity with serial culture passaging.

Science.gov (United States)

Dinardo, Carla Luana; Venturini, Gabriela; Omae, Samantha Vieira; Zhou, Enhua H; da Motta-Leal-Filho, Joaquim Maurício; Dariolli, Rafael; Krieger, José Eduardo; Alencar, Adriano Mesquita; Costa Pereira, Alexandre

2012-01-01

One drawback of in vitro cell culturing is the dedifferentiation process that cells experience. Smooth muscle cells (SMC) also change molecularly and morphologically with long term culture. The main objective of this study was to evaluate if culture passages interfere in vascular SMC mechanical behavior. SMC were obtained from five different porcine arterial beds. Optical magnetic twisting cytometry (OMTC) was used to characterize mechanically vascular SMC from different cultures in distinct passages and confocal microscopy/western blotting, to evaluate cytoskeleton and extracellular matrix proteins. We found that vascular SMC rigidity or viscoelastic complex modulus (G) decreases with progression of passages. A statistically significant negative correlation between G and passage was found in four of our five cultures studied. Phalloidin-stained SMC from higher passages exhibited lower mean signal intensity per cell (confocal microscopy) and quantitative western blotting analysis showed a decrease in collagen I content throughout passages. We concluded that vascular SMC progressively lose their stiffness with serial culture passaging. Thus, limiting the number of passages is essential for any experiment measuring viscoelastic properties of SMC in culture.

ATP-containing vesicles in stria vascular marginal cell cytoplasms in neonatal rat cochlea are lysosomes.

Science.gov (United States)

Liu, Jun; Liu, Wenjing; Yang, Jun

2016-02-11

We confirmed that ATP is released from cochlear marginal cells in the stria vascular but the cell organelle in which ATP stores was not identified until now. Thus, we studied the ATP-containing cell organelles and suggest that these are lysosomes. Primary cultures of marginal cells of Sprague-Dawley rats aged 1-3 days was established. Vesicles within marginal cells stained with markers were identified under confocal laser scanning microscope and transmission electron microscope (TEM). Then ATP release from marginal cells was measured after glycyl-L-phenylalanine-ß- naphthylamide (GPN) treatment using a bioluminescent assay. Quinacrine-stained granules within marginal cells were labeled with LysoTracker, a lysosome tracer, and lysosomal-associated membrane protein 1(LAMP1), but not labeled with the mitochondrial tracer MitoTracker. Furthermore, LysoTracker-labelled puncta showed accumulation of Mant-ATP, an ATP analog. Treatment with 200 μM GPN quenched fluorescently labeled puncta after incubation with LysoTracker or quinacrine, but not MitoTracker. Quinacrine-labeled organelles observed by TEM were lysosomes, and an average 27.7 percent increase in ATP luminescence was observed in marginal cells extracellular fluid after GPN treatment. ATP-containing vesicles in cochlear marginal cells of the stria vascular from neonatal rats are likely lysosomes. ATP release from marginal cells may be via Ca(2+)-dependent lysosomal exocytosis.

Vascular filtration function in galactose-fed versus diabetic rats: The role of polyol pathway activity

Energy Technology Data Exchange (ETDEWEB)

Pugliese, G.; Tilton, R.G.; Speedy, A.; Chang, K.; Province, M.A.; Kilo, C.; Williamson, J.R. (Washington Univ. School of Medicine, St Louis, MO (USA))

1990-07-01

These studies were undertaken to assess the effects of increased galactose (v increased glucose) metabolism via the polyol pathway on vascular filtration function in the kidneys, eyes, nerves, and aorta. Quantitative radiolabeled tracer techniques were used to assess glomerular filtration rate (GFR) and regional tissue vascular clearance of plasma 131I-bovine serum albumin (BSA) in five groups of male Sprague-Dawley rats: nondiabetic controls, streptozotocin-diabetic rats, nondiabetic rats fed a 50% galactose diet, diabetic rats treated with sorbinil (an aldose reductase inhibitor), and galactose-fed rats treated with sorbinil. Sorbinil was added to the diet to provide a daily dose of approximately .2 mmol/kg body weight. After 2 months of diabetes or galactose ingestion, albumin clearance was increased twofold to fourfold in the eye (anterior uvea, choroid, and retina), sciatic nerve, aorta, and kidney; GFR was increased approximately twofold and urinary excretion of endogenous albumin and IgG were increased approximately 10-fold. Sorbinil treatment markedly reduced or completely prevented all of these changes in galactose-fed, as well as in diabetic rats. These observations support the hypothesis that increased metabolism of glucose via the sorbitol pathway is of central importance in mediating virtually all of the early changes in vascular filtration function associated with diabetes in the kidney, as well as in the eyes, nerves, and aorta. On the other hand, renal hypertrophy in diabetic rats and polyuria, hyperphagia, and impaired weight gain in galactose-fed and in diabetic rats were unaffected by sorbinil and therefore are unlikely to be mediated by increased polyol metabolism.

Vascular filtration function in galactose-fed versus diabetic rats: The role of polyol pathway activity

International Nuclear Information System (INIS)

Pugliese, G.; Tilton, R.G.; Speedy, A.; Chang, K.; Province, M.A.; Kilo, C.; Williamson, J.R.

1990-01-01

These studies were undertaken to assess the effects of increased galactose (v increased glucose) metabolism via the polyol pathway on vascular filtration function in the kidneys, eyes, nerves, and aorta. Quantitative radiolabeled tracer techniques were used to assess glomerular filtration rate (GFR) and regional tissue vascular clearance of plasma 131I-bovine serum albumin (BSA) in five groups of male Sprague-Dawley rats: nondiabetic controls, streptozotocin-diabetic rats, nondiabetic rats fed a 50% galactose diet, diabetic rats treated with sorbinil (an aldose reductase inhibitor), and galactose-fed rats treated with sorbinil. Sorbinil was added to the diet to provide a daily dose of approximately .2 mmol/kg body weight. After 2 months of diabetes or galactose ingestion, albumin clearance was increased twofold to fourfold in the eye (anterior uvea, choroid, and retina), sciatic nerve, aorta, and kidney; GFR was increased approximately twofold and urinary excretion of endogenous albumin and IgG were increased approximately 10-fold. Sorbinil treatment markedly reduced or completely prevented all of these changes in galactose-fed, as well as in diabetic rats. These observations support the hypothesis that increased metabolism of glucose via the sorbitol pathway is of central importance in mediating virtually all of the early changes in vascular filtration function associated with diabetes in the kidney, as well as in the eyes, nerves, and aorta. On the other hand, renal hypertrophy in diabetic rats and polyuria, hyperphagia, and impaired weight gain in galactose-fed and in diabetic rats were unaffected by sorbinil and therefore are unlikely to be mediated by increased polyol metabolism

Exogenous BMP7 in aortae of rats with chronic uremia ameliorates expression of profibrotic genes, but does not reverse established vascular calcification

DEFF Research Database (Denmark)

Gravesen, Eva; Lerche Mace, Maria; Nordholm, Anders

2018-01-01

Hyperphosphatemia and vascular calcification are frequent complications of chronic renal failure and bone morphogenetic protein 7 (BMP7) has been shown to protect against development of vascular calcification in uremia. The present investigation examined the potential reversibility of established...... uremic vascular calcification by treatment of uremic rats with BMP7. A control model of isogenic transplantation of a calcified aorta from uremic rats into healthy littermates examined whether normalization of the uremic environment reversed vascular calcification. Uremia and vascular calcification were...... induced in rats by 5/6 nephrectomy, high phosphate diet and alfacalcidol treatment. After 14 weeks severe vascular calcification was present and rats were allocated to BMP7, vehicle or aorta transplantation. BMP7 treatment caused a significant decrease of plasma phosphate to 1.56 ± 0.17 mmol/L vs 2.06 ± 0...

Prevention of hemodynamic and vascular albumin filtration changes in diabetic rats by aldose reductase inhibitors

International Nuclear Information System (INIS)

Tilton, R.G.; Chang, K.; Pugliese, G.; Eades, D.M.; Province, M.A.; Sherman, W.R.; Kilo, C.; Williamson, J.R.

1989-01-01

This study investigated hemodynamic changes in diabetic rats and their relationship to changes in vascular albumin permeation and increased metabolism of glucose to sorbitol. The effects of 6 wk of streptozocin-induced diabetes and three structurally different inhibitors of aldose reductase were examined on (1) regional blood flow (assessed with 15-microns 85Sr-labeled microspheres) and vascular permeation by 125I-labeled bovine serum albumin (BSA) and (2) glomerular filtration rate (assessed by plasma clearance of 57Co-labeled EDTA) and urinary albumin excretion (determined by radial immunodiffusion assay). In diabetic rats, blood flow was significantly increased in ocular tissues (anterior uvea, posterior uvea, retina, and optic nerve), sciatic nerve, kidney, new granulation tissue, cecum, and brain. 125I-BSA permeation was increased in all of these tissues except brain. Glomerular filtration rate and 24-h urinary albumin excretion were increased 2- and 29-fold, respectively, in diabetic rats. All three aldose reductase inhibitors completely prevented or markedly reduced these hemodynamic and vascular filtration changes and increases in tissue sorbitol levels in the anterior uvea, posterior uvea, retina, sciatic nerve, and granulation tissue. These observations indicate that early diabetes-induced hemodynamic changes and increased vascular albumin permeation and urinary albumin excretion are aldose reductase-linked phenomena. Discordant effects of aldose reductase inhibitors on blood flow and vascular albumin permeation in some tissues suggest that increased vascular albumin permeation is not entirely attributable to hemodynamic change

Tributyltin chloride increases phenylephrine-induced contraction and vascular stiffness in mesenteric resistance arteries from female rats

International Nuclear Information System (INIS)

Ribeiro Júnior, Rogério Faustino; Marques, Vinicius Bermond; Nunes, Dieli Oliveira; Ronconi, Karoline de Sousa; Araújo, Julia F.P. de; Rodrigues, Paula Lopes; Padilha, Alessandra Simão; Vassallo, Dalton Valentim; Graceli, Jones B.; Stefanon, Ivanita

2016-01-01

Tributyltin chloride (TBT) is an organotin compound that reduces estrogen levels in female rats. We aimed to investigate the effects of TBT exposure on vascular tonus and vascular remodelling in the resistance arteries of female rats. Rats were treated daily with TBT (500 ng/kg) for 15 days. TBT did not change arterial blood pressure but did modify some morpho-physiological parameters of third-order mesenteric resistance arteries in the following ways: (1) decreased lumen and external diameters; (2) increased wall/lm ratio and wall thickness; (3) decreased distensibility and increased stiffness; (4) increased collagen deposition; and (5) increased pulse wave velocity. TBT exposure increased the phenylephrine-induced contractile response in mesenteric resistance arteries. However, vasodilatation responses induced by acetylcholine and sodium nitroprusside were not modified by TBT. It is suggested that TBT exposure reduces vascular nitric oxide (NO) production, because:(1) L-NAME incubation did not cause a leftward shift in the concentration–response curve for phenylephrine; (2) both eNOS protein expression; (3) in situ NO production were reduced. Incubation with L-NAME; and (4) SOD shifted the phenylephrine response curve to the left in TBT rats. Tiron, catalase, ML-171 and VAS2870 decreased vascular reactivity to phenylephrine only in TBT rats. Moreover, increased superoxide anion production was observed in the mesenteric resistance arteries of TBT rats accompanied by an increase in gp91phox, catalase, AT 1 receptor and total ERK1/2 protein expression. In conclusion, these findings show that TBT induced alterations are most likely due to a reduction of NO production combined with increased O 2 − production derived from NADPH oxidase and ERK1/2 activation. These findings offer further evidence that TBT is an environmental risk factor for cardiovascular disease. - Highlights: • Tributyltin chloride reduces estrogen levels in female rats. • Treatment with TBT

Tributyltin chloride increases phenylephrine-induced contraction and vascular stiffness in mesenteric resistance arteries from female rats

Energy Technology Data Exchange (ETDEWEB)

Ribeiro Júnior, Rogério Faustino, E-mail: rogeriofaustinoribeiro@hotmail.com [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Marques, Vinicius Bermond; Nunes, Dieli Oliveira; Ronconi, Karoline de Sousa [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Araújo, Julia F.P. de [Department of Morphology, Federal University of Espírito Santo (Brazil); Rodrigues, Paula Lopes; Padilha, Alessandra Simão; Vassallo, Dalton Valentim [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Graceli, Jones B. [Department of Morphology, Federal University of Espírito Santo (Brazil); Stefanon, Ivanita [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil)

2016-03-15

Tributyltin chloride (TBT) is an organotin compound that reduces estrogen levels in female rats. We aimed to investigate the effects of TBT exposure on vascular tonus and vascular remodelling in the resistance arteries of female rats. Rats were treated daily with TBT (500 ng/kg) for 15 days. TBT did not change arterial blood pressure but did modify some morpho-physiological parameters of third-order mesenteric resistance arteries in the following ways: (1) decreased lumen and external diameters; (2) increased wall/lm ratio and wall thickness; (3) decreased distensibility and increased stiffness; (4) increased collagen deposition; and (5) increased pulse wave velocity. TBT exposure increased the phenylephrine-induced contractile response in mesenteric resistance arteries. However, vasodilatation responses induced by acetylcholine and sodium nitroprusside were not modified by TBT. It is suggested that TBT exposure reduces vascular nitric oxide (NO) production, because:(1) L-NAME incubation did not cause a leftward shift in the concentration–response curve for phenylephrine; (2) both eNOS protein expression; (3) in situ NO production were reduced. Incubation with L-NAME; and (4) SOD shifted the phenylephrine response curve to the left in TBT rats. Tiron, catalase, ML-171 and VAS2870 decreased vascular reactivity to phenylephrine only in TBT rats. Moreover, increased superoxide anion production was observed in the mesenteric resistance arteries of TBT rats accompanied by an increase in gp91phox, catalase, AT{sub 1} receptor and total ERK1/2 protein expression. In conclusion, these findings show that TBT induced alterations are most likely due to a reduction of NO production combined with increased O{sub 2}{sup −} production derived from NADPH oxidase and ERK1/2 activation. These findings offer further evidence that TBT is an environmental risk factor for cardiovascular disease. - Highlights: • Tributyltin chloride reduces estrogen levels in female rats. �

Vascular thermal adaptation in tumors and normal tissue in rats

International Nuclear Information System (INIS)

Nah, Byung Sik; Choi, Ihl-Bohng; Oh, Won Young; Osborn, James L.; Song, Chang W.

1996-01-01

Purpose: The vascular thermal adaptation in the R3230 adenocarcinoma, skin and muscle in the legs of Fischer rats was studied. Methods and Materials: The legs of Fischer rats bearing the R3230 AC adenocarcinoma (subcutaneously) were heated once or twice with a water bath, and the blood flow in the tumor, skin and muscle of the legs was measured with the radioactive microsphere method. Results: The blood flow in control R3230 AC tumors was 23.9 ml/100 g/min. The tumor blood flow increased about 1.5 times in 30 min and then markedly decreased upon heating at 44.5 deg. C for 90 min. In the tumors preheated 16 h earlier at 42.5 deg. C for 60 min, reheating at 44.5 deg. C increased the tumor blood flow by 2.5-fold in 30 min. Contrary to the decline in blood flow following an initial increase during the 44.5 deg. C heating without preheating, the tumor blood flow remained elevated throughout the 90 min reheating at 44.5 deg. C. These results indicated that thermal adaptation or thermotolerance developed in the tumor vasculatures after the preheating at 42.5 deg. C for 60 min. The magnitude of vascular thermal adaptation in the tumors 24 h and 48 h after the preheating, as judged from the changes in blood flow, were smaller than that 16 h after the preheating. Heating at 42.5 deg. C for 60 min induced vascular thermal adaptation also in the skin and muscle, which peaked in 48 h and 24 h, respectively, after the heating. Conclusion: Heating at 42.5 deg. C for 1 h induced vascular thermal adaptation in the R3230 AC tumor, skin, and muscle of rats that peaked 16-48 h after the heating. When the tumor blood vessels were thermally adapted, the tumor blood flow increased upon heating at temperatures that would otherwise reduce the tumor blood flow. Such an increase in tumor blood flow may hinder raising the tumor temperature while it may increase tumor oxygenation.

Junctional transfer in cultured vascular endothelium: II. Dye and nucleotide transfer

International Nuclear Information System (INIS)

Larson, D.M.; Sheridan, J.D.

1985-01-01

Vascular endothelial cultures, derived from large vessels, retain many of the characteristics of their in vivo counterparts. However, the observed reduction in size and complexity of intercellular gap and tight junctions in these cultured cells suggests that important functions, thought to be mediated by these structures, may be altered in vitro. In continuing studies on intercellular communication in vessel wall cells, the authors have quantitated the extent of junctional transfer of small molecular tracers (the fluorescent dye Lucifer Yellow CH and tritiated uridine nucleotides) in confluent cultures of calf aortic (BAEC) and umbilical vein (BVEC) endothelium. Both BAEC and BVEC show extensive (and quantitatively equivalent) dye and nucleotide transfer. As an analogue of intimal endothelium, the authors have also tested dye transfer in freshly isolated sheets of endothelium. Transfer in BAEC and BVEC sheets was more rapid, extensive and homogeneous than in the cultured cells, implying a reduction in molecular coupling as endothelium adapts to culture conditions. In addition, they have documented heterocellular nucleotide transfer between cultured endothelium and vascular smooth muscle cells, of particular interest considering the prevalence of ''myo-endothelial'' junctions in vivo. These data yield further information on junctional transfer in cultured vascular endothelium and have broad implications for the functional integration of the vessel wall in the physiology and pathophysiology of the vasculature

Phytoestrogens Enhance the Vascular Actions of the Endocannabinoid Anandamide in Mesenteric Beds of Female Rats

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Roxana N. Peroni

2012-01-01

Full Text Available In rat isolated mesenteric beds that were contracted with NA as an in vitro model of the vascular adrenergic hyperactivity that usually precedes the onset of primary hypertension, the oral administration (3 daily doses of either 10 mg/kg genistein or 20 mg/kg daidzein potentiated the anandamide-induced reduction of contractility to NA in female but not in male rats. Oral treatment with phytoestrogens also restored the vascular effects of anandamide as well as the mesenteric content of calcitonin gene-related peptide (CGRP that were reduced after ovariectomy. The enhancement of anandamide effects caused by phytoestrogens was prevented by the concomitant administration of the estrogen receptor antagonist fulvestrant (2.5 mg/kg, s.c., 3 daily doses. It is concluded that, in the vasculature of female rats, phytoestrogens produced an estrogen-receptor-dependent enhancement of the anandamide-vascular actions that involves the modulation of CGRP levels and appears to be relevant whenever an adrenergic hyperactivity occurs.

Organ culture of C57BL/6 mouse arteries with LPS as an in vitro model of vascular inflammation

DEFF Research Database (Denmark)

Outzen, Emilie Middelbo; Mehryar, Rahila; Boonen, Harrie C.M.

Background: Vascular inflammation is believed to be involved in the pathogenesis of various cardiovascular diseases, the study of which often involves use of the mouse strain C57BL/6. In vivo studies can, however, be difficult to control and interpret. Aim of the study: To set up and characterise...... an in vitro model for studying vascular inflammation and function in cultured arteries from C57BL/6 mice. Methods: Segments of abdominal aorta and mesenteric arteries (MA) were incubated for 24 hours at 37̊C and 95% O2/5% CO2 in DMEM ± 100 ng/mL LPS. Aorta segments were frozen for molecular studies...... was achieved at a normalisation factor of 0.9 (0.91 ± 0.06, mean ± SEM, n = 9) as observed (0.85 ± 0.06, mean ± SEM, n = 3) and previously described in rat MA (Mulvany and Halpern, 1977). Furthermore, preliminary findings show that organ culture with 100 ng/mL LPS decreases endothelium-dependent dilation of C...

Vascular Adventitia Calcification and Its Underlying Mechanism.

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Na Li

Full Text Available Previous research on vascular calcification has mainly focused on the vascular intima and media. However, we show here that vascular calcification may also occur in the adventitia. The purpose of this work is to help elucidate the pathogenic mechanisms underlying vascular calcification. The calcified lesions were examined by Von Kossa staining in ApoE-/- mice which were fed high fat diets (HFD for 48 weeks and human subjects aged 60 years and older that had died of coronary heart disease, heart failure or acute renal failure. Explant cultured fibroblasts and smooth muscle cells (SMCswere obtained from rat adventitia and media, respectively. After calcification induction, cells were collected for Alizarin Red S staining. Calcified lesions were observed in the aorta adventitia and coronary artery adventitia of ApoE-/-mice, as well as in the aorta adventitia of human subjects examined. Explant culture of fibroblasts, the primary cell type comprising the adventitia, was successfully induced for calcification after incubation with TGF-β1 (20 ng/ml + mineralization media for 4 days, and the phenotype conversion vascular adventitia fibroblasts into myofibroblasts was identified. Culture of SMCs, which comprise only a small percentage of all cells in the adventitia, in calcifying medium for 14 days resulted in significant calcification.Vascular calcification can occur in the adventitia. Adventitia calcification may arise from the fibroblasts which were transformed into myofibroblasts or smooth muscle cells.

Short-term treatment with VEGF receptor inhibitors induces retinopathy of prematurity-like abnormal vascular growth in neonatal rats.

Science.gov (United States)

Nakano, Ayuki; Nakahara, Tsutomu; Mori, Asami; Ushikubo, Hiroko; Sakamoto, Kenji; Ishii, Kunio

2016-02-01

Retinal arterial tortuosity and venous dilation are hallmarks of plus disease, which is a severe form of retinopathy of prematurity (ROP). In this study, we examined whether short-term interruption of vascular endothelial growth factor (VEGF) signals leads to the formation of severe ROP-like abnormal retinal blood vessels. Neonatal rats were treated subcutaneously with the VEGF receptor (VEGFR) tyrosine kinase inhibitors, KRN633 (1, 5, or 10 mg/kg) or axitinib (10 mg/kg), on postnatal day (P) 7 and P8. The retinal vasculatures were examined on P9, P14, or P21 in retinal whole-mounts stained with an endothelial cell marker. Prevention of vascular growth and regression of some preformed capillaries were observed on P9 in retinas of rats treated with KRN633. However, on P14 and P21, density of capillaries, tortuosity index of arterioles, and diameter of veins significantly increased in KRN633-treated rats, compared to vehicle (0.5% methylcellulose)-treated animals. Similar observations were made with axitinib-treated rats. Expressions of VEGF and VEGFR-2 were enhanced on P14 in KRN633-treated rat retinas. The second round of KRN633 treatment on P11 and P12 completely blocked abnormal retinal vascular growth on P14, but thereafter induced ROP-like abnormal retinal blood vessels by P21. These results suggest that an interruption of normal retinal vascular development in neonatal rats as a result of short-term VEGFR inhibition causes severe ROP-like abnormal retinal vascular growth in a VEGF-dependent manner. Rats treated postnatally with VEGFR inhibitors could serve as an animal model for studying the mechanisms underlying the development of plus disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tributyltin chloride disrupts aortic vascular reactivity and increases reactive oxygen species production in female rats.

Science.gov (United States)

Ximenes, Carolina Falcão; Rodrigues, Samya Mere Lima; Podratz, Priscila Lang; Merlo, Eduardo; de Araújo, Julia Fernandez Puñal; Rodrigues, Lívia Carla Melo; Coitinho, Juliana Barbosa; Vassallo, Dalton Valentim; Graceli, Jones Bernardes; Stefanon, Ivanita

2017-11-01

Organotin compounds, such as tributyltin (TBT), are environment contaminants that induce bioaccumulation and have potential toxic effects on marine species and mammals. TBT have been banned by the International Maritime Organization in 2003. However, the assessment of butyltin and metal contents in marine sediments has demonstrated high residual levels of TBT in some cases exceeding 7000 ng Sn g -1 . The acceptable daily intake (ADI) level for TBT established by the World Health Organization is 0.5 μg/kg bw/day is based on genotoxicity, reproduction, teratogenicity, immunotoxicity, and mainly neurotoxicity. However, their effect on the cardiovascular system is not well understood. In this study, female rats were exposed to 0.5 μg/kg/day of TBT for 15 days with the goal of understanding the effect of TBT on vascular function. Female Wistar rats were treated daily by gavage and divided into control (n = 10) and TBT (n = 10) groups. The aortic rings were incubated with phenylephrine in both the presence and absence of endothelium. The phenylephrine concentration-response curves were generated by exposing endothelium-intact samples to N G -nitro-L-arginine methyl ester (L-NAME), apocynin, superoxide dismutase (SOD), catalase, tiron, and allopurinol. Acetylcholine (ACh) and sodium nitroprusside (SNP) were used to evaluate the relaxation response. Exposure to TBT reduced serum 17β-estradiol E 2 levels and increased vascular reactivity. After incubation with L-NAME, the vascular reactivity to phenylephrine was significantly higher. Apocynin, SOD, catalase, and tiron decreased the vascular reactivity to phenylephrine to a significantly greater extent in TBT-treated rats than in the control rat. The relaxation induced by ACh and SNP was significantly reduced in TBT rats. Exposure to TBT induced aortic wall atrophy and increased superoxide anion production and collagen deposition. These results provide evidence that exposing rats to the current ADI for TBT (0.5�

Inhibition of Extracellular Signal-Regulated Kinases Ameliorates Hypertension-Induced Renal Vascular Remodeling in Rat Models

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Li Jing

2011-11-01

Full Text Available The aim of this study is to investigate the effect of the extracellular signal-regulated kinases 1/2 (ERK1/2 inhibitor, PD98059, on high blood pressure and related vascular changes. Blood pressure was recorded, thicknesses of renal small artery walls were measured and ERK1/2 immunoreactivity and erk2 mRNA in renal vascular smooth muscle cells (VSMCs and endothelial cells were detected by immunohistochemistry and in situ hybridization in normotensive wistar kyoto (WKY rats, spontaneously hypertensive rats (SHR and PD98059-treated SHR. Compared with normo-tensive WKY rats, SHR developed hypertension at 8 weeks of age, thickened renal small artery wall and asymmetric arrangement of VSMCs at 16 and 24 weeks of age. Phospho-ERK1/2 immunoreactivity and erk2 mRNA expression levels were increased in VSMCs and endothelial cells of the renal small arteries in the SHR. Treating SHR with PD98059 reduced the spontaneous hypertension-induced vascular wall thickening. This effect was associated with suppressions of erk2 mRNA expression and ERK1/2 phosphorylation in VSMCs and endothelial cells of the renal small arteries. It is concluded that inhibition of ERK1/2 ameliorates hypertension induced vascular remodeling in renal small arteries.

Acetylcholine-induced vasodilation in the uterine vascular bed of pregnant rats with adriamycin-induced nephrosis.

Science.gov (United States)

Yousif, Mariam H; Adeagbo, Ayotunde S; Kadavil, Elizabeth A; Chandrasekhar, Bindu; Oriowo, Mabayoje A

2002-01-01

This project was designed to study endothelium-dependent vasodilation in the uterine vascular bed during experimentally induced preeclampsia in rats. Uterine vascular beds were isolated from non-pregnant and pregnant rats with or without treatment with adriamycin (ADR) and perfused with physiological solution. Thereafter, vasodilator responses to acetylcholine were recorded. RECORDS: Pregnant ADR-treated rats displayed symptoms of preeclampsia including hypertension and proteinuria. Blood pressure was 110.0 +/- 4.7 mm Hg (n = 5) in control pregnant rats and 136.0 +/- 5.3 mm Hg (n = 5) in ADR-treated pregnant rats, and urinary protein concentrations were 0.35 mg/ml (n = 5) and 13.2 +/- 3.6 mg/ml (n = 9), respectively. Both blood pressure and proteinuria values were significantly (p acetylcholine-induced dose-dependent vasodilator responses in the vascular beds were not significantly different between the pregnant and nonpregnant rats. Although acetylcholine-induced vasodilation was significantly reduced by N omega-nitro-L-arginine methyl ester hydrochloride (L-NAME) in both groups, the residual response to acetylcholine was not affected by indomethacin, suggesting that prostanoids were not involved in this response. The L-NAME-resistant component, endothelium-derived hyperpolarizing factor (EDHF), was greater in ADR-treated uterine beds than in those of the controls, indicating a significant contribution from EDHF in these vessels. In the presence of an elevated external potassium ion concentration, acetylcholine produced similar vasodilator responses, indicating that the release of nitric oxide was not impaired. These results indicate that endothelium-dependent vasodilation was not impaired in this model of preeclampsia.

Tributyltin chloride increases phenylephrine-induced contraction and vascular stiffness in mesenteric resistance arteries from female rats.

Science.gov (United States)

Ribeiro Júnior, Rogério Faustino; Marques, Vinicius Bermond; Nunes, Dieli Oliveira; Ronconi, Karoline de Sousa; de Araújo, Julia F P; Rodrigues, Paula Lopes; Padilha, Alessandra Simão; Vassallo, Dalton Valentim; Graceli, Jones B; Stefanon, Ivanita

2016-03-15

Tributyltin chloride (TBT) is an organotin compound that reduces estrogen levels in female rats. We aimed to investigate the effects of TBT exposure on vascular tonus and vascular remodelling in the resistance arteries of female rats. Rats were treated daily with TBT (500 ng/kg) for 15 days. TBT did not change arterial blood pressure but did modify some morpho-physiological parameters of third-order mesenteric resistance arteries in the following ways: (1) decreased lumen and external diameters; (2) increased wall/lm ratio and wall thickness; (3) decreased distensibility and increased stiffness; (4) increased collagen deposition; and (5) increased pulse wave velocity. TBT exposure increased the phenylephrine-induced contractile response in mesenteric resistance arteries. However, vasodilatation responses induced by acetylcholine and sodium nitroprusside were not modified by TBT. It is suggested that TBT exposure reduces vascular nitric oxide (NO) production, because:(1) L-NAME incubation did not cause a leftward shift in the concentration-response curve for phenylephrine; (2) both eNOS protein expression; (3) in situ NO production were reduced. Incubation with L-NAME; and (4) SOD shifted the phenylephrine response curve to the left in TBT rats. Tiron, catalase, ML-171 and VAS2870 decreased vascular reactivity to phenylephrine only in TBT rats. Moreover, increased superoxide anion production was observed in the mesenteric resistance arteries of TBT rats accompanied by an increase in gp91phox, catalase, AT1 receptor and total ERK1/2 protein expression. In conclusion, these findings show that TBT induced alterations are most likely due to a reduction of NO production combined with increased O2(-) production derived from NADPH oxidase and ERK1/2 activation. These findings offer further evidence that TBT is an environmental risk factor for cardiovascular disease. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of electroacupuncture on the expression of mTOR and eIF4E in hippocampus of rats with vascular dementia.

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Zhu, Yanzhen; Zeng, Yanjun; Wang, Xuan; Ye, Xiaobao

2013-07-01

Clinically, electroacupuncture is proved to be an effective therapy for vascular dementia; however, their mechanisms remain uncertain. The aim of the current study was to investigate the mechanism of electroacupuncture therapy for vascular dementia. One month after a vascular dementia animal model was established by bilateral occlusion of common carotid arteries, electroacupuncture treatment was given at "Baihui" (DU20), "Dazhui" (DU14), and "Shenshu" (BL23). Morris water maze was used to assess the learning and memory ability of rats. Western blot assay was performed to detect the expression of mammalian target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E (eIF4E) in hippocampus of rats. Morris water maze test showed that electroacupuncture improved the learning ability of vascular dementia rats. Western blot assay revealed that the expression level of mTOR and eIF4E in the electroacupuncture group and sham-operated group was higher than that in the vascular dementia group (P Electroacupuncture improves learning and memory ability by up-regulating expression of mTOR and eIF4E in the hippocampus of vascular dementia rats.

Defibrotide modulates prostaglandin production in the rat mesenteric vascular bed.

Science.gov (United States)

Peredo, H A

2002-10-01

Defibrotide 1 microM, a polydeoxyribonucleotide extracted from mammalian organs, reduced the contractile responses to noradrenaline (NA) in the rat isolated and perfused mesenteric vascular bed, in intact as well as in de-endothelialized preparations. Defibrotide was without effect on the acetylcholine-induced relaxations of U-46619-precontracted mesenteric vascular beds. Moreover, defibrotide increased 6-keto prostaglandin (PG) F(2alpha) (stable metabolite of prostacyclin) release sixfold in the presence, but not in the absence of the endothelium, with no modification on the release of other prostanoids. Defibrotide also inhibited the NA-induced increase in PGF(2alpha) release, in both intact and de-endothelialized mesenteric vascular beds. In conclusion, the present results show that defibrotide modulates PG production in the mesenteric bed and that the observed inhibition of the contractile responses should be due to the impairment of the NA-induced increase in PGF(2alpha) release.

Response of the sensorimotor cortex of cerebral palsy rats receiving transplantation of vascular endothelial growth factor 165-transfected neural stem cells

Institute of Scientific and Technical Information of China (English)

Jielu Tan; Xiangrong Zheng; Shanshan Zhang; Yujia Yang; Xia Wang; Xiaohe Yu; Le Zhong

2014-01-01

Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge-nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into ifve groups: (1) sham operation (control), (2) cerebral palsy model alone or with (3) phosphate-buffered saline, (4) vascular en-dothelial growth factor 165 + neural stem cells, or (5) neural stem cells alone. hTe cerebral palsy model was established by ligating the letf common carotid artery followed by exposure to hypox-ia. Phosphate-buffered saline, vascular endothelial growth factor + neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. Atfer transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas-cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for ifnding water and the ifnding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. hTese ifndings indicate that the transplantation of vascu-lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deifcits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.

Modulation of hemodynamic and vascular filtration changes in diabetic rats by dietary myo-inositol

International Nuclear Information System (INIS)

Pugliese, G.; Tilton, R.G.; Speedy, A.; Santarelli, E.; Eades, D.M.; Province, M.A.; Kilo, C.; Sherman, W.R.; Williamson, J.R.

1990-01-01

To assess the potential of myo-inositol-supplemented diets to prevent diabetes-induced vascular functional changes, we examined the effects of diets supplemented with 0.5, 1, or 2% myo-inositol on blood flow and vascular filtration function in nondiabetic control rats and rats with streptozocin-induced diabetes (STZ-D). After 1 mo of diabetes and dietary myo-inositol supplementation, (1) 131I-labeled bovine serum albumin (BSA) permeation of vessels was assessed in multiple tissues, (2) glomerular filtration rate (GFR) was estimated as renal plasma clearance of 57Co-labeled EDTA, (3) regional blood flows were measured with 15-microns 85Sr-labeled microspheres, and (4) endogenous albumin and IgG urinary excretion rates were quantified by radial immunodiffusion assay. In STZ-D rats, 131I-BSA tissue clearance increased significantly (2- to 4-fold) in the anterior uvea, choroid-sclera, retina, sciatic nerve, aorta, new granulation tissue, diaphragm, and kidney but was unchanged in skin, forelimb muscle, and heart. myo-Inositol-supplemented diets reduced diabetes-induced increases in 131I-BSA clearance (in a dose-dependent manner) in all tissues; however, only in new granulation tissue and diaphragm did the 2% myo-inositol diet completely normalize vascular albumin permeation. Diabetes-induced increases in GFR and in urinary albumin and IgG excretion were also substantially reduced or normalized by dietary myo-inositol supplements. Increased blood flow in anterior uvea, choroid-sclera, kidney, new granulation tissue, and skeletal muscle in STZ-D rats also was substantially reduced or normalized by the 2% myo-inositol diet. myo-Inositol had minimal if any effects on the above parameters in control rats

Expression of smooth muscle and non-muscle myosin heavy chain isoforms in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Rovner, A.S.; Murphy, R.A.; Owens, G.K.

1986-01-01

Immunocytochemical studies of cultured smooth muscle cells (SMCs) have disagreed on the nature of myosin expression. This investigation was undertaken to test for the presence of heterogeneous myosin heavy chain (MHC) isoforms in cell culture as a possible explanation for these results. Previously, Rovner et al. detected two MHCs in intact smooth muscles which differed in molecular weight by ca. 4000 daltons (SM1 and SM2) using a 3-4% acrylamide gradient SDS gel system. When sub-confluent primary cultures of rat aorta SMCs were assayed by this system, SM1 and SM2 were seen, along with large amounts of a third, unique MHC, NM, which closely resembled the MHC from human platelet in size and antigenicity. Data from 35 S-methionine autoradiograms showed that the log growth phase SMC cultures were producing almost exclusively NM, but the growth arrest, post-confluent cultures synthesized increased relative amounts of the SM MHC forms and contained comparable amounts of SM1, SM2, and NM. The same patterns of MHC synthesis were seen in sub-passaged SMCs. The expression of the SM-specific forms of myosin in quiescent, post-confluent cultures parallels that of smooth muscle actin suggesting that density induced growth arrest promotes cytodifferentiation in cultured vascular SMCs

Down-regulation of endothelin binding sites in rat vascular smooth muscle cells

International Nuclear Information System (INIS)

Roubert, P.; Gillard, V.; Plas, P.; Chabrier, P.E.; Braquet, P.

1990-01-01

In cultured rat aortic smooth muscle cells, [ 125 I]endothelin (ET-1) bound to an apparent single class of high affinity recognition sites with a dissociation constant of 1.84 +/- 0.29 nmol/L and a maximum binding of 62 +/- 10.5 fmol/10(6) cells. The binding was not affected by calcium antagonists or vasoactive substances, including angiotensin II, arginine vasopressin, atrial natriuretic factor and bradykinin. Exposure of the cells to ET-1 (0.01 nmol/L to 10 nmol/L) resulted in an apparent dose-dependent reduction of the number of endothelin binding sites with no significant modification of its binding affinity. The time course of the down-regulation of ET-1 binding sites showed that this effect was present after 30 min incubation and persisted after 18 h. This indicates that down-regulation of ET-1 binding sites can modulate the activity of ET-1 and suggests a rapid internalization of ET-1 in vascular cells

Tributyltin contributes in reducing the vascular reactivity to phenylephrine in isolated aortic rings from female rats.

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Rodrigues, Samya Mere L; Ximenes, Carolina F; de Batista, Priscila R; Simões, Fabiana V; Coser, Pedro Henrique P; Sena, Gabriela C; Podratz, Priscila L; de Souza, Leticia N G; Vassallo, Dalton V; Graceli, Jones B; Stefanon, Ivanita

2014-03-21

Organotin compounds such as tributyltin (TBT) are used as antifouling paints by shipping companies. TBT inhibits the aromatase responsible for the transformation of testosterone into estrogen. Our hypothesis is that TBT modulates the vascular reactivity of female rats. Female Wistar rats were treated daily (Control; CONT) or TBT (100 ng/kg) for 15 days. Rings from thoracic aortas were incubated with phenylephrine (PHE, 10(-10)-10(-4) M) in the presence and absence of endothelium, and in the presence of N(G)-Nitro-L-Arginine Methyl Ester (L-NAME), tetraethylammonium (TEA) and apocynin. TBT decreased plasma levels of estrogen and the vascular response to PHE. In the TBT group, the vascular reactivity was increased in the absence of endothelium, L-NAME and TEA. The decrease in PHE reactivity during incubation with apocynin was more evident in the TBT group. The sensitivity to acetylcholine (ACh) and sodium nitroprusside (SNP) was reduced in the TBT group. TBT increased collagen, reduced α1-smooth muscle actin. Female rats treated with TBT for 15 days showed morphology alteration of the aorta and decreased their vascular reactivity, probably due to mechanisms dependent on nitric oxide (NO) bioavailability, K(+) channels and an increase in oxidative stress. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Self-Condensation Culture Enables Vascularization of Tissue Fragments for Efficient Therapeutic Transplantation

Directory of Open Access Journals (Sweden)

Yoshinobu Takahashi

2018-05-01

Full Text Available Summary: Clinical transplantation of tissue fragments, including islets, faces a critical challenge because of a lack of effective strategies that ensure efficient engraftment through the timely integration of vascular networks. We recently developed a complex organoid engineering method by “self-condensation” culture based on mesenchymal cell-dependent contraction, thereby enabling dissociated heterotypic lineages including endothelial cells to self-organize in a spatiotemporal manner. Here, we report the successful adaptation of this method for generating complex tissues from diverse tissue fragments derived from various organs, including pancreatic islets. The self-condensation of human and mouse islets with endothelial cells not only promoted functionalization in culture but also massively improved post-transplant engraftment. Therapeutically, fulminant diabetic mice were more efficiently treated by a vascularized islet transplant compared with the conventional approach. Given the general limitations of post-transplant vascularization associated with 3D tissue-based therapy, our approach offers a promising means of enhancing efficacy in the context of therapeutic tissue transplantation. : Takahashi et al. report on generating vascularized islet tissue from humans and mice. After transplantation, vascularized islets significantly improve survival of diabetic mice, demonstrating the quick normalization of blood glucose compared with conventional islet transplantation. Keywords: tissue engineering, tissue-based therapy, vascularization, islet transplantation, organoid

The role of L-type calcium channels in the vascular effect of Trigonella foenum-graecum L. in diabetic rats

Directory of Open Access Journals (Sweden)

Mehrdad Roghani

2006-03-01

Full Text Available Some ion channels like voltage-operated calcium channels (VOCC within the plasma membrane of vascular muscle cells from the walls of resistance arteries and arterioles play a central role in the regulation of vascular tone. On the basis of reports about the beneficial attenuating effect of fenugreek (Trigonella foenum-graecum L.; TFG on the contractile reactivity of aortic rings of diabetic rats, this study was carried out to evaluate the possible involvement of L-type voltage-operated calcium channels in the vascular effect of this medicinal plant. For this purpose, male Wistar rats were made diabetic using streptozotocin (STZ, 60 mg/Kg, i.p. The extract-treated control and diabetic rats received aqueous leaf extract of TFG (200 mg/Kg, i.p. every other day for two months. At the end of the study, contractile response of isolated aortic rings to KCl and noreadrenaline (NA was determined in the absence and presence of the calcium channel blocker nifedipine. The results showed that aortic rings from diabetic rats are more responsive to the effect of KCl and NA than those of controls, TFG extract treatment could attenuate the enhanced contractile response of aortic rings of diabetic rats, and nifedipine pretreatment could partially neutralize the beneficial effect of this extract. It is concluded that TFG extract attenuates the enhanced vascular reactivity in chronic diabetic rats and voltage-operated calcium channels are in part responsible for this effect of TFG extract.

The effects of chronic resveratrol treatment on vascular responsiveness of streptozotocin-induced diabetic rats.

Science.gov (United States)

Silan, Coskun

2008-05-01

Deficiency in the vasorelaxant capacity is a result of an oxidative stress in diabetic animals and seems to be an etiological factor of vascular complications of diabetes. The present study was designed to examine whether resveratrol (RSV), a polyphenolic compound which is naturally present in grape and red wine, has a protective effect on diabetic aorta. Resveratrol (5 mg/kg/d, i.p.) was administered for 42 d to streptozotocin (STZ) (60 mg/kg) induced diabetic rats. Loss of weight, hyperglycemia, and elevated levels of plasma malondialdehyde (MDA) were observed in diabetic rats. Resveratrol treatment was significantly effective for these metabolic and biochemical abnormalities. The contractile responses of the aorta were recorded. Compared with control subjects, the aorta showed significantly enhanced contractile responses to noradrenaline (NA), but not to potassium chloride (KCl), in diabetic rats. Treatment of diabetic rats with resveratrol significantly reversed the increases in responsiveness and sensitivity of aorta to noradrenaline. In diabetic aorta, the relaxation response to acetylcholine (Ach) was found to be significantly decreased compared with control subjects, and resveratrol treatment reversed this; no such change was observed in the relaxation response to sodium nitroprusside (SNP). These results indicated that resveratrol significantly improved not only glucose metabolism and oxidative injury but also impaired vascular responses in streptozotocin induced diabetic rats.

Cloning and characterization of rat density-enhanced phosphatase-1, a protein tyrosine phosphatase expressed by vascular cells.

Science.gov (United States)

Borges, L G; Seifert, R A; Grant, F J; Hart, C E; Disteche, C M; Edelhoff, S; Solca, F F; Lieberman, M A; Lindner, V; Fischer, E H; Lok, S; Bowen-Pope, D F

1996-09-01

We have cloned from cultured vascular smooth muscle cells a protein tyrosine phosphatase, rat density-enhanced phosphatase-1 (rDEP-1), which is a probable rat homologue of DEP-1/HPTP eta. rDEP-1 is encoded by an 8.7-kb transcript and is expressed as a 180- to 220-kD protein. The rDEP-1 gene is located on human chromosome 11 (region p11.2) and on mouse chromosome 2 (region 2E). The cDNA sequence predicts a transmembrane protein consisting of a single phosphatase catalytic domain in the intracellular region, a single transmembrane domain, and eight fibronectin type III repeats in the extracellular region (GenBank accession number U40790). In situ hybridization analysis demonstrates that rDEP-1 is widely expressed in vivo but that expression is highest in cells that form epithelioid monolayers. In cultured cells with epitheliod morphology, including endothelial cells and newborn smooth muscle cells, but not in fibroblast-like cells, rDEP-1 transcript levels are dramatically upregulated as population density increases. In vivo, quiescent endothelial cells in normal arteries express relatively high levels of rDEP-1. During repair of vascular injury, expression of rDEP-1 is downregulated in migrating and proliferating endothelial cells. In vivo, rDEP-1 transcript levels are present in very high levels in megakaryocytes, and circulating plates have high levels of the rDEP-1 protein. In vitro, initiation of differentiation of the human megakaryoblastic cell line CHRF-288-11 with phorbol 12-myristate 13-acetate leads to a very strong upregulation of rDEP-1 transcripts. The deduced structure and the regulation of expression of rDEP-1 suggest that it may play a role in adhesion and/or signaling events involving cell-cell and cell-matrix contact.

Co-Seeding Human Endothelial Cells with Human-Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells on Calcium Phosphate Scaffold Enhances Osteogenesis and Vascularization in Rats.

Science.gov (United States)

Liu, Xian; Chen, Wenchuan; Zhang, Chi; Thein-Han, Wahwah; Hu, Kevin; Reynolds, Mark A; Bao, Chongyun; Wang, Ping; Zhao, Liang; Xu, Hockin H K

2017-06-01

A major challenge in repairing large bone defects with tissue-engineered constructs is the poor vascularization in the defect. The lack of vascular networks leads to insufficient oxygen and nutrients supply, which compromises the survival of seeded cells. To achieve favorable regenerative effects, prevascularization of tissue-engineered constructs by co-culturing of endothelial cells and bone cells is a promising strategy. The aim of this study was to investigate the effects of human-induced pluripotent stem cell-derived mesenchymal stem cells (hiPSC-MSCs) co-cultured with human umbilical vein endothelial cells (HUVECs) for prevascularization of calcium phosphate cement (CPC) scaffold on bone regeneration in vivo for the first time. HUVECs co-cultured with hiPSC-MSCs formed microcapillary-like structures in vitro. HUVECs promoted mineralization of hiPSC-MSCs on CPC scaffolds. Four groups were tested in a cranial bone defect model in nude rats: (1) CPC scaffold alone (CPC control); (2) HUVEC-seeded CPC (CPC-HUVEC); (3) hiPSC-MSC-seeded CPC (CPC-hiPSC-MSC); and (4) HUVECs co-cultured with hiPSC-MSCs on CPC scaffolds (co-culture group). After 12 weeks, the co-culture group achieved the greatest new bone area percentage of 46.38% ± 3.8% among all groups (p < 0.05), which was more than four folds of the 10.61% ± 1.43% of CPC control. In conclusion, HUVECs co-cultured with hiPSC-MSCs substantially promoted bone regeneration. The novel construct of HUVECs co-cultured with hiPSC-MSCs delivered via CPC scaffolds is promising to enhance bone and vascular regeneration in orthopedic applications.

Deuterium oxide normalizes blood pressure and vascular calcium uptake in Dahl salt-sensitive hypertensive rats

International Nuclear Information System (INIS)

Vasdev, S.; Prabhakaran, V.; Sampson, C.A.

1990-01-01

This study examined the effect of 25% deuterium oxide in drinking water on systolic blood pressure, uptakes of calcium, and rubidium 86 by aortas of Dahl salt-sensitive rats on 0.4% (low) and 8% (high) sodium chloride (salt) diet. Twenty-four rats were divided into four groups. Groups I and II were on the low salt diet and groups III and IV on the high salt diet from 6 weeks of age. Additionally, at 10 weeks of age groups I and III were placed on 100% water and groups II and IV on 25% deuterium oxide. At 14 weeks, systolic blood pressure, uptakes of calcium, and rubidium 86 by aortas were significantly higher (p less than 0.01) in rats on the high salt diet as compared with those on the low salt diet. Deuterium oxide intake normalized systolic blood pressure and aortic calcium uptake but not aortic rubidium 86 uptake in hypertensive rats on the high salt diet. Deuterium oxide had no effect on blood pressure or aortic calcium uptake in rats on the low salt diet. The parallel increase in systolic blood pressure and vascular calcium uptake suggests that increased calcium uptake mechanisms are associated with hypertension in salt-sensitive Dahl rats. Furthermore, deuterium oxide appears to normalize elevated blood pressure in salt-sensitive hypertensive rats by normalizing elevated vascular (aortic) calcium uptake

Experimental study of icariin on vascular dementia in rats induced by 2-VO method

Institute of Scientific and Technical Information of China (English)

Rui-xiaXU; QinWU; Jing-shanSHI

2004-01-01

AIM: To study the effects of icariin (ICA) on the learning and memory of ischemic vascular dementia (VD) model of rats,and explore the protective mechanisms. METHODS: ICA was administered to the VD model rats induced by a permanent bilateral occlusion of both common carotids arteries(2-VO method) and by cerebral ischemia-reperfusion (I10-R 10-110 method). Morris water maze was used to examine the abilities of spatial learning and memory of VD model rats. The activity of SOD, level of

Successful ovarian autotransplant with no vascular reanastomosis in rats.

Science.gov (United States)

Barros, Flávio S V; de Oliveira, Rodrigo M; Alves, Felipe M T; Sampaio, Marcos; Geber, Selmo

2008-12-15

Preservation of ovarian functions in woman with premature ovarian failure remains an issue in reproductive medicine. Hormone replacement therapy for maintaining endocrine functions, and cryopreservation of embryos or oocytes for those who wish pregnancy, are some of the choices. However, ovarian transplantation is a more physiological alternative, although problems related to ovarian ischemia have been reported. Herein, we investigated the viability of autologous transplantation of the ovarian tissue into the rat peritoneum, without vascular reanastomosis. Twenty animals in the study group had both ovaries excised, and each ovary was dissected into two halves. A half of an ovary was autotransplanted to the peritoneal surface, closely located to the left epigastric vessels. This simple procedure does not require surgical vascular reanastomosis while it maintains appropriate follicular growth and therefore should be further considered as an alternative for women undergoing oophorectomy, not only to maintain endocrine functions but also for fertility preservation.

Hypoxic contraction of cultured pulmonary vascular smooth muscle cells

International Nuclear Information System (INIS)

Murray, T.R.; Chen, L.; Marshall, B.E.; Macarak, E.J.

1990-01-01

The cellular events involved in generating the hypoxic pulmonary vasoconstriction response are not clearly understood, in part because of the multitude of factors that alter pulmonary vascular tone. The goal of the present studies was to determine if a cell culture preparation containing vascular smooth muscle (VSM) cells could be made to contract when exposed to a hypoxic atmosphere. Cultures containing only fetal bovine pulmonary artery VSM cells were assessed for contractile responses to hypoxic stimuli by two methods. In the first, tension forces generated by cells grown on a flexible growth surface (polymerized polydimethyl siloxane) were manifested as wrinkles and distortions of the surface under the cells. Wrinkling of the surface was noted to progressively increase with time as the culture medium bathing the cells was made hypoxic (PO2 approximately 25 mmHg). The changes were sometimes reversible upon return to normoxic conditions and appeared to be enhanced in cells already exhibiting evidence of some baseline tone. Repeated passage in culture did not diminish the hypoxic response. Evidence for contractile responses to hypoxia was also obtained from measurements of myosin light chain (MLC) phosphorylation. Conversion of MLC to the phosphorylated species is an early step in the activation of smooth muscle contraction. Lowering the PO2 in the culture medium to 59 mmHg caused a 45% increase in the proportion of MLC in the phosphorylated form as determined by two-dimensional gel electrophoresis. Similarly, cultures preincubated for 4 h with 32P and then exposed to normoxia or hypoxia for a 5-min experimental period showed more than twice as much of the label in MLCs of the hypoxic cells

Benfotiamine attenuates nicotine and uric acid-induced vascular endothelial dysfunction in the rat.

Science.gov (United States)

Balakumar, Pitchai; Sharma, Ramica; Singh, Manjeet

2008-01-01

The study has been designed to investigate the effect of benfotiamine, a thiamine derivative, in nicotine and uric acid-induced vascular endothelial dysfunction (VED) in rats. Nicotine (2 mg kg(-1)day(-1), i.p., 4 weeks) and uric acid (150 mg kg(-1)day(-1), i.p., 3 weeks) were administered to produce VED in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum and aortic concentration of nitrite/nitrate. Further, the integrity of vascular endothelium was assessed using the scanning electron microscopy (SEM) of thoracic aorta. Moreover, the oxidative stress was assessed by estimating serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion generation. The administration of nicotine and uric acid produced VED by impairing the integrity of vascular endothelium and subsequently decreasing serum and aortic concentration of nitrite/nitrate and attenuating acetylcholine-induced endothelium dependent relaxation. Further, nicotine and uric acid produced oxidative stress, which was assessed in terms of increase in serum TBARS and aortic superoxide generation. However, treatment with benfotiamine (70 mg kg(-1)day(-1), p.o.) or atorvastatin (30 mg kg(-1)day(-1) p.o., a standard agent) markedly prevented nicotine and uric acid-induced VED and oxidative stress by improving the integrity of vascular endothelium, increasing the concentration of serum and aortic nitrite/nitrate, enhancing the acetylcholine-induced endothelium dependent relaxation and decreasing serum TBARS and aortic superoxide anion generation. Thus, it may be concluded that benfotiamine reduces the oxidative stress and consequently improves the integrity of vascular endothelium and enhances the generation of nitric oxide to prevent nicotine and uric acid-induced experimental VED.

Resistance of essential fatty acid-deficient rats to endotoxin-induced increases in vascular permeability

International Nuclear Information System (INIS)

Li, E.J.; Cook, J.A.; Spicer, K.M.; Wise, W.C.; Rokach, J.; Halushka, P.V.

1990-01-01

Resistance to endotoxin in essential fatty acid-deficient (EFAD) rats is associated with reduced synthesis of certain arachidonic acid metabolites. It was hypothesized that EFAD rats would manifest decreased vascular permeability changes during endotoxemia as a consequence of reduced arachidonic acid metabolism. To test this hypothesis, changes in hematocrit (HCT) and mesenteric localization rate of technetium-labeled human serum albumin (99mTc-HSA) and red blood cells (99mTc-RBC) were assessed in EFAD and normal rats using gamma-camera imaging. Thirty minutes after Salmonella enteritidis endotoxin, EFAD rats exhibited less hemoconcentration as determined by % HCT than normal rats. Endotoxin caused a less severe change in permeability index in the splanchnic region in EFAD rats than in normal rats (1.2 +/- 0.6 x 10(-3)min-1 vs. 4.9 +/- 1.7 x 10(-3)min-1 respectively, P less than 0.05). In contrast to 99mTc-HSA, mesenteric localization of 99mTc-RBC was not changed by endotoxin in control or EFAD rats. Supplementation with ethyl-arachidonic acid did not enhance susceptibility of EFAD rats to endotoxin-induced splanchnic permeability to 99mTc-HSA. Leukotrienes have been implicated as mediators of increased vascular permeability in endotoxin shock. Since LTC3 formation has been reported to be increased in EFA deficiency, we hypothesized that LTC3 may be less potent than LTC4. Thus the effect of LTC3 on mean arterial pressure and permeability was compared to LTC4 in normal rats. LTC3-induced increases in peak mean arterial pressure were less than LTC4 at 10 micrograms/kg (39 +/- 5 mm Hg vs. 58 +/- 4 mm Hg respectively, P less than 0.05) and at 20 micrograms/kg (56 +/- 4 mm Hg vs. 75 +/- 2 mm Hg respectively, P less than 0.05). LY171883 (30 mg/kg), an LTD4/E4 receptor antagonist, attenuated the pressor effect of LTC4, LTD4, and LTC3

Developmental programming of vascular dysfunction by prenatal and postnatal zinc deficiency in male and female rats.

Science.gov (United States)

Mendes Garrido Abregú, Facundo; Gobetto, María Natalia; Juriol, Lorena Vanesa; Caniffi, Carolina; Elesgaray, Rosana; Tomat, Analía Lorena; Arranz, Cristina

2018-06-01

Micronutrient malnutrition during intrauterine and postnatal growth may program cardiovascular diseases in adulthood. We examined whether moderate zinc restriction in male and female rats throughout fetal life, lactation and/or postweaning growth induces alterations that can predispose to the onset of vascular dysfunction in adulthood. Female Wistar rats were fed low- or control zinc diets from pregnancy to offspring weaning. After weaning, offspring were fed either a low- or a control zinc diet until 81 days. We evaluated systolic blood pressure (SBP), thoracic aorta morphology, nitric oxide (NO) system and vascular reactivity in 6- and/or 81-day-old offspring. At day 6, zinc-deficient male and female offspring showed a decrease in aortic NO synthase (NOS) activity accompanied by an increase in oxidative stress. Zinc-deficient 81-day-old male rats exhibited an increase in collagen deposition in tunica media, as well as lower activity of endothelial NOS (eNOS) that could not be reversed with an adequate zinc diet during postweaning life. Zinc deficiency programmed a reduction in eNOS protein expression and higher SBP only in males. Adult zinc-deficient rats of both sexes showed reduced vasodilator response dependent on eNOS activity and impaired aortic vasoconstrictor response to angiotensin-II associated with alterations in intracellular calcium mobilization. Female rats were less sensitive to the effects of zinc deficiency and exhibited higher eNOS activity and/or expression than males, without alterations in SBP or aortic histology. This work strengthens the importance of a balanced intake of micronutrients during perinatal growth to ensure adequate vascular function in adult life. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

International Nuclear Information System (INIS)

Silva, Tharciano Luiz Teixeira Braga da; Mota, Marcelo Mendonça; Fontes, Milene Tavares; Araújo, João Eliakim dos Santos; Carvalho, Vitor Oliveira; Bonjardim, Leonardo Rigoldi; Santos, Márcio Roberto Viana

2015-01-01

Hypertension is a public health problem and increases the incidence of cardiovascular diseases. To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of N G -nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats. Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP). Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H. One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

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Silva, Tharciano Luiz Teixeira Braga da; Mota, Marcelo Mendonça; Fontes, Milene Tavares; Araújo, João Eliakim dos Santos; Carvalho, Vitor Oliveira; Bonjardim, Leonardo Rigoldi; Santos, Márcio Roberto Viana, E-mail: marciorvsantos@bol.com.br [Universidade Federal de Sergipe, Universidade de São Paulo (Brazil)

2015-08-15

Hypertension is a public health problem and increases the incidence of cardiovascular diseases. To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of N{sup G}-nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats. Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP). Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H. One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.

Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

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Tharciano Luiz Teixeira Braga da Silva

2015-01-01

Full Text Available Abstract Background: Hypertension is a public health problem and increases the incidence of cardiovascular diseases. Objective: To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of NG-nitro L-arginine methyl ester (L-NAME-induced hypertensive rats. Methods: Wistar rats were divided into three groups: control (C, hypertensive (H, and exercised hypertensive (EH. Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN, potassium chloride (KCl and sodium nitroprusside (SNP. Results: Rats treated with L-NAME showed an increase (p < 0.001 in systolic blood pressure (SBP, diastolic blood pressure (DBP and mean arterial pressure (MAP compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001 the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01 smooth muscle sensitivity to NPS was observed in group EH as compared to group H. Conclusion: One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.

Elastase effect on the extracellular matrix of rat aortic smooth muscle cells in culture

International Nuclear Information System (INIS)

Kispert, J.; Mogayzel, P.J. Jr.; Pratt, C.A.; Toselli, P.; Wolfe, B.L.; Faris, B.; Franzblau, C.

1986-01-01

The effect of porcine pancreatic elastase on the extracellular matrix (ECM) of neonatal rat aortic smooth muscle cell cultures was monitored both chemically and ultrastructurally. Initially, the elastin appeared as non-coalesced material closely associated with filaments, presumably microfibrils. The insoluble elastin accumulated in the ECM of cells in culture for 6 weeks accounted for 40-45% of the total protein. After exposure to elastase for 30-60 minutes, the elastin content was reduced to 14-20%. The reduction in the total protein content of the cultures after elastase treatment was due primarily to the loss of elastin. Although the amino acid compositions of the elastin isolated from cultures both before and after elastase treatment were similar, there were striking ultrastructural differences in the amorphous elastin. The elastin assumed a mottled appearance after elastase exposure, similar to that seen in in vivo emphysema models. Pulse experiments with 3 H-valine demonstrated an increase in protein synthesis by the cells 20 hours after elastase exposure, suggesting the potential for elastin repair. The use of this culture system will aid in clarifying the role of elastolysis in pulmonary and vascular injuries

Vascularized anal autotransplantation model in rats: preliminary report.

Science.gov (United States)

Araki, J; Mihara, M; Narushima, M; Iida, T; Sato, T; Koshima, I

2011-11-01

Ostomy has served as an effective surgery for various anorectal disfunctions. However, it must also be noted that those patients suffered greatly from stresses caused by their stoma. Many alternative therapies have been developed, but none have solved this critical issue. Meanwhile, due to the improvements in operative methods and immunosuppressive therapy, allotranplantation has gained great popularity in recent years. Therefore, we began development of an anal transplantation model. The operation was performed in six adult Wistar rats that were divided into two groups. Group 1 underwent vascular anastomoses, while group 2 did not Group 1 grafts survived, fully recovering anal function. However, many of the group 2 grafts did not survive; those that did survive showed major defects in their anus, never recovering anal function. We succeeded in establishing the rat anal transplantation model utilizing super-microsurgery. While research in anal transplantation was behind compared to that in other fields, we hope that this model will bring significant possibilities for the future. Copyright © 2011 Elsevier Inc. All rights reserved.

Long-term organ culture of adult rat colon

DEFF Research Database (Denmark)

Shamsuddin, A.K.M.; Barrett, L.A.; Autrup, Herman

1978-01-01

. The effect of in vivo carcinogen pretreatment was also studied. The explant culture from control untreated animals showed good epithelial differentiation with crypts until 6 weeks. In contrast, the explants from animals pretreated with 4 weekly doses of azoxymethane consistently showed epithelial......Colon explants from adult rats were maintained in culture for over 3 months in our laboratories with good epithelial preservation and cellular differentiation. The light and transmission electron microscopic features of rat colon mucosa during the culture period are described. In all the explants...

Chronic lead exposure decreases the vascular reactivity of rat aortas: the role of hydrogen peroxide.

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Karolini Zuqui Nunes

Full Text Available We investigated whether exposure to small concentrations of lead alters blood pressure and vascular reactivity. Male Wistar rats were sorted randomly into the following two groups: control (Ct and treatment with 100 ppm of lead (Pb, which was added to drinking water, for 30 days. Systolic blood pressure (BP was measured weekly. Following treatment, aortic ring vascular reactivity was assessed. Tissue samples were properly stored for further biochemical investigation. The lead concentration in the blood reached approximately 8 μg/dL. Treatment increased blood pressure and decreased the contractile responses of the aortic rings to phenylephrine (1 nM-100 mM. Following N-nitro-L arginine methyl ester (L-NAME administration, contractile responses increased in both groups but did not differ significantly between them. Lead effects on Rmax were decreased compared to control subjects following superoxide dismutase (SOD administration. Catalase, diethyldithiocarbamic acid (DETCA, and apocynin increased the vasoconstrictor response induced by phenylephrine in the aortas of lead-treated rats but did not increase the vasoconstrictor response in the aortas of untreated rats. Tetraethylammonium (TEA potentiated the vasoconstrictor response induced by phenylephrine in aortic segments in both groups, but these effects were greater in lead-treated rats. The co-incubation of TEA and catalase abolished the vasodilatory effect noted in the lead group. The present study is the first to demonstrate that blood lead concentrations well below the values established by international legislation increased blood pressure and decreased phenylephrine-induced vascular reactivity. The latter effect was associated with oxidative stress, specifically oxidative stress induced via increases in hydrogen peroxide levels and the subsequent effects of hydrogen peroxide on potassium channels.

The impact of various scaffold components on vascularized bone constructs.

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Eweida, Ahmad; Schulte, Matthias; Frisch, Oliver; Kneser, Ulrich; Harhaus, Leila

2017-06-01

Bone tissue engineering is gaining more interest in the field of craniofacial surgery where continuous efforts are being made to improve the outcomes via modulation of the scaffold components. In an in vitro three dimensional (3D) culture, the effect of bone morphogenic protein 2 (BMP2, 60 μg/ml) and the effect of different cell seeding densities (0.25, 0.5, and 1 × 104) of rat mesenchymal stem cells seeded on nanocrystalline hydroxyapatite in silica gel matrix (Nanobone ® ) on the cell viability and differentiation were studied. Alkaline phosphatase and viability assays were performed at day 7, day 14, and day 21 to assess the differentiation and the relative fraction of viable cells in the 3D cell cultures. In a subsequent in vivo study, we examined the effect of axial vascularization, the scaffold's particle size and the nature of the matrix (collagen type I vs. diluted fibrin) on vascularization and tissue generation in vascularized bone construct in rats. Regarding vascularization, we compared constructs vascularized randomly by extrinsic vascularization from the periphery of the implanted construct with others vascularized axially via an implanted arteriovenous loop (AVL). Regarding the particle size, we compared constructs having a scaffold particle size of 0.2 mm (powder) with other constructs having a particle size of 2 × 0.6 mm (granules). Regarding the matrix we compared constructs having a collagen matrix with others having a fibrin matrix. Various groups were compared regarding the amount of tissue generation, vascularization, and cellular proliferation. The initial seeding density had a temporary and minimal effect on the overall osteogenic differentiation of the cells. On the contrary, adding BMP2 in a concentration of 60 μg/ml over one week led to an overall enhanced osteogenic differentiation despite depressed cell viability. Axial vascularization was mandatory for efficient tissue formation and vascularization of the bone construct

Magnesium prevents phosphate-induced vascular calcification via TRPM7 and Pit-1 in an aortic tissue culture model.

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Sonou, Tomohiro; Ohya, Masaki; Yashiro, Mitsuru; Masumoto, Asuka; Nakashima, Yuri; Ito, Teppei; Mima, Toru; Negi, Shigeo; Kimura-Suda, Hiromi; Shigematsu, Takashi

2017-06-01

Previous clinical and experimental studies have indicated that magnesium may prevent vascular calcification (VC), but mechanistic characterization has not been reported. This study investigated the influence of increasing magnesium concentrations on VC in a rat aortic tissue culture model. Aortic segments from male Sprague-Dawley rats were incubated in serum-supplemented high-phosphate medium for 10 days. The magnesium concentration in this medium was increased to demonstrate its role in preventing VC, which was assessed by imaging and spectroscopy. The mineral composition of the calcification was analyzed using Fourier transform infrared (FTIR) spectroscopic imaging, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) mapping. Magnesium supplementation of high-phosphate medium dose-dependently suppressed VC (quantified as aortic calcium content), and almost ablated it at 2.4 mm magnesium. The FTIR images and SEM-EDX maps indicated that the distribution of phosphate (as hydroxyapatite), phosphorus and Mg corresponded with calcium content in the aortic ring and VC. The inhibitory effect of magnesium supplementation on VC was partially reduced by 2-aminoethoxy-diphenylborate, an inhibitor of TRPM7. Furthermore, phosphate transporter-1 (Pit-1) protein expression was increased in tissues cultured in HP medium and was gradually-and dose dependently-decreased by magnesium. We conclude that a mechanism involving TRPM7 and Pit-1 underpins the magnesium-mediated reversal of high-phosphate-associated VC.

Effect of Caffeic Acid Phenethyl Ester on Vascular Damage Caused by Consumption of High Fructose Corn Syrup in Rats.

Science.gov (United States)

Gun, Aburrahman; Ozer, Mehmet Kaya; Bilgic, Sedat; Kocaman, Nevin; Ozan, Gonca

2016-01-01

Fructose corn syrup is cheap sweetener and prolongs the shelf life of products, but fructose intake causes hyperinsulinemia, hypertriglyceridemia, and hypertension. All of them are referred to as metabolic syndrome and they are risk factors for cardiovascular diseases. Hence, the harmful effects of increased fructose intake on health and their prevention should take greater consideration. Caffeic Acid Phenethyl Ester (CAPE) has beneficial effects on metabolic syndrome and vascular function which is important in the prevention of cardiovascular disease. However, there are no known studies about the effect of CAPE on fructose-induced vascular dysfunction. In this study, we examined the effect of CAPE on vascular dysfunction due to high fructose corn syrup (HFCS). HFCS (6 weeks, 30% fed with drinking water) caused vascular dysfunction, but treatment with CAPE (50 micromol/kg i.p. for the last two weeks) effectively restored this problem. Additionally, hypertension in HFCS-fed rats was also decreased in CAPE supplemented rats. CAPE supplements lowered HFCS consumption-induced raise in blood glucose, homocysteine, and cholesterol levels. The aorta tissue endothelial nitric oxide synthase (eNOS) production was decreased in rats given HFCS and in contrast CAPE supplementation efficiently increased its production. The presented results showed that HFCS-induced cardiovascular abnormalities could be prevented by CAPE treatment.

Effect of Caffeic Acid Phenethyl Ester on Vascular Damage Caused by Consumption of High Fructose Corn Syrup in Rats

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Aburrahman Gun

2016-01-01

Full Text Available Fructose corn syrup is cheap sweetener and prolongs the shelf life of products, but fructose intake causes hyperinsulinemia, hypertriglyceridemia, and hypertension. All of them are referred to as metabolic syndrome and they are risk factors for cardiovascular diseases. Hence, the harmful effects of increased fructose intake on health and their prevention should take greater consideration. Caffeic Acid Phenethyl Ester (CAPE has beneficial effects on metabolic syndrome and vascular function which is important in the prevention of cardiovascular disease. However, there are no known studies about the effect of CAPE on fructose-induced vascular dysfunction. In this study, we examined the effect of CAPE on vascular dysfunction due to high fructose corn syrup (HFCS. HFCS (6 weeks, 30% fed with drinking water caused vascular dysfunction, but treatment with CAPE (50 micromol/kg i.p. for the last two weeks effectively restored this problem. Additionally, hypertension in HFCS-fed rats was also decreased in CAPE supplemented rats. CAPE supplements lowered HFCS consumption-induced raise in blood glucose, homocysteine, and cholesterol levels. The aorta tissue endothelial nitric oxide synthase (eNOS production was decreased in rats given HFCS and in contrast CAPE supplementation efficiently increased its production. The presented results showed that HFCS-induced cardiovascular abnormalities could be prevented by CAPE treatment.

Vascular permeabilization by intravenous arachidonate in the rat peritoneal cavity: antagonism by ethamsylate.

Science.gov (United States)

Hannaert, Patrick; Alvarez-Guerra, Miriam; Hider, Hamida; Chiavaroli, Carlo; Garay, Ricardo P

2003-04-11

The hemostatic agent, ethamsylate, inhibits arachidonic acid metabolism by a mechanism independent of cyclooxygenase activity and blocks carrageenan-induced rat paw edema. Here, ethamsylate was investigated for (i) in vivo actions on the free radical-dependent, permeabilizing responses to arachidonic acid and (ii) its antioxidant potential in vitro. Vascular permeability was equated to the extravasation rate of Evans blue from plasma into the rat peritoneal cavity. Antioxidant potential was investigated by classical in vitro tests for superoxide radicals, hydroxyl radicals (OH(.)), and nitric oxide. Intravenous ethamsylate induced a very important and significant reduction of permeability responses to arachidonate, both when given preventively and cumulatively. Thus, (i) ethamsylate significantly reversed arachidonate-induced permeabilization, even at the lowest dose tested (44+/-5% at 10 mg/kg) and (ii) a maximal reversal (about 70%) was reached between 50 and 200 mg/kg ethamsylate. In contrast, ethamsylate (100 mg/kg) was unable to antagonize the vascular permeabilization induced by serotonin (5-HT). In antioxidant assays, ethamsylate showed scavenging properties against hydroxyl radicals generated by the Fenton reaction (H(2)O(2)/Fe(2+)) even at 0.1 microM (-20+/-3%). OH(.) scavenging by ethamsylate reached 42+/-8% at 10 microM and 57+/-7% at 1 mM and was comparable to that of reference compounds (vitamin E, troxerutin, and mannitol). Conversely, ethamsylate was a poor scavenger of superoxide and nitric oxide radicals. In conclusion, intravenous ethamsylate potently antagonized the peritoneal vascular permeabilization induced by arachidonate, an action likely due to its antioxidant properties, particularly against hydroxyl radical. Such a mechanism can explain previous observations that ethamsylate inhibits carrageenan-induced rat paw edema. Whether it also participates in the hemostatic action of ethamsylate deserves further investigation.

Na,K-pump modulates intercellular communication in vascular wall

DEFF Research Database (Denmark)

Matchkov, Vladimir

were used as a model for electrical coupling of SMCs by measuring membrane capacitance (Cm). SMCs were uncoupled (evaluated by inhibition of vasomotion and desynchronization of calcium transients in vascular wall, or by reduction to half of Cm measured in paired A7r5 cells) when the Na......  Ouabain, a specific inhibitor of the Na,K-pump, has previously been shown to interfere with intercellular communication. Here we test the hypothesis that the communication between vascular smooth muscle cells (SMCs) is regulated through an interaction between the Na,K-pump and the Na......,Ca-exchanger leading to an increase in the intracellular calcium concentration in discrete areas near the plasma membrane. The intracellular calcium concentration in individual SMCs was imaged in cultured rat aortic SMCs (A7r5) and simultaneously with isometric force in rat mesenteric small arteries. Paired A7r5 cells...

White matter damage and glymphatic dysfunction in a model of vascular dementia in rats with no prior vascular pathologies.

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Venkat, Poornima; Chopp, Michael; Zacharek, Alex; Cui, Chengcheng; Zhang, Li; Li, Qingjiang; Lu, Mei; Zhang, Talan; Liu, Amy; Chen, Jieli

2017-02-01

We investigated cognitive function, axonal/white matter (WM) changes and glymphatic function of vascular dementia using a multiple microinfarction (MMI) model in retired breeder (RB) rats. The MMI model induces significant (p rats subjected to MMI exhibit significant axonal/WM damage identified by decreased myelin thickness, oligodendrocyte progenitor cell numbers, axon density, synaptic protein expression in the cortex and striatum, cortical neuronal branching, and dendritic spine density in the cortex and hippocampus compared with age-matched controls. MMI evokes significant dilation of perivascular spaces as well as water channel dysfunction indicated by decreased Aquaporin-4 expression around blood vessels. MMI-induced glymphatic dysfunction with delayed cerebrospinal fluid penetration into the brain parenchyma via paravascular pathways as well as delayed waste clearance from the brain. The MMI model in RB rats decreases Aquaporin-4 and induces glymphatic dysfunction which may play an important role in MMI-induced axonal/WM damage and cognitive deficits. Copyright © 2016 Elsevier Inc. All rights reserved.

Oxidative stress contributes to soluble fms-like tyrosine kinase-1 induced vascular dysfunction in pregnant rats.

Science.gov (United States)

Bridges, Jason P; Gilbert, Jeffrey S; Colson, Drew; Gilbert, Sara A; Dukes, Matthew P; Ryan, Michael J; Granger, Joey P

2009-05-01

Recent evidence indicates that both increased oxidative stress and an altered balance between pro- and anti-angiogenic factors such as vascular-endothelial growth factor (VEGF) and the soluble VEGF receptor (sFlt-1) contribute to endothelial dysfunction in preeclampsia. We hypothesized that chronic infusion of sFlt-1 to mimic the increase observed in preeclamptic patients would reduce plasma VEGF concentrations, increase blood pressure (BP) and vascular superoxide levels, and cause endothelial dysfunction in the pregnant rat. Recombinant sFlt-1 was infused (500 ng/h) during days 13-18 of pregnancy. BP, fetal and placental weight, oxidative stress and vessel vasorelaxation were determined on day 18 of pregnancy. Plasma sFlt-1 concentrations (299 +/- 33 vs. 100 +/- 16 pg/ml; P 570 +/- 77 vs. 780 +/- 48 pg/ml; P < 0.01) were decreased when compared to vehicle infused dams. sFlt-1 rats had smaller fetuses (1.3 +/- 0.03 vs. 1.5 +/- 0.04 g, P < 0.01) and placentas (0.41 +/- 0.01 vs. 0.47 +/- 0.02 g; P < 0.05). Placental (180 +/- 66 vs. 24 +/- 2.3 RLU/min/mg; P < 0.05) and vascular (34 +/- 8 vs. 12 +/- 5 RLU/min/mg; P < 0.05) superoxide production was increased in the sFlt-1 compared to vehicle infused rats. Vasorelaxation to acetylecholine (ACh) and sodium nitroprusside (SNP) were both decreased (P < 0.05) in the sFlt-1 infusion group compared to the vehicle and this decrease was attenuated (P < 0.05) by the superoxide scavenger Tiron. These data indicate elevated maternal sFlt-1 and decreased VEGF concentrations results in increased oxidative stress that contributes to vascular dysfunction during pregnancy.

Rice bran protein hydrolysates reduce arterial stiffening, vascular remodeling and oxidative stress in rats fed a high-carbohydrate and high-fat diet.

Science.gov (United States)

Senaphan, Ketmanee; Sangartit, Weerapon; Pakdeechote, Poungrat; Kukongviriyapan, Veerapol; Pannangpetch, Patchareewan; Thawornchinsombut, Supawan; Greenwald, Stephen E; Kukongviriyapan, Upa

2018-02-01

Rice bran protein hydrolysates (RBPH) contain highly nutritional proteins and antioxidant compounds which show benefits against metabolic syndrome (MetS). Increased arterial stiffness and the components of MetS have been shown to be associated with an increased risk of cardiovascular disease. This study aimed to investigate whether RBPH could alleviate the metabolic disorders, arterial stiffening, vascular remodeling, and oxidative stress in rats fed a high-carbohydrate and high-fat (HCHF) diet. Male Sprague-Dawley rats were fed either a standard chow and tap water or a HCHF diet and 15 % fructose solution for 16 weeks. HCHF rats were treated orally with RBPH (250 or 500 mg/kg/day) for the final 6 weeks of the experimental period. Rats fed with HCHF diet had hyperglycemia, insulin resistance, dyslipidemia, hypertension, increased aortic pulse wave velocity, aortic wall hypertrophy and vascular remodeling with increased MMP-2 and MMP-9 expression. RBPH supplementation significantly alleviated these alterations (P stress was also alleviated after RBPH treatment by decreasing plasma malondialdehyde, reducing superoxide production and suppressing p47 phox NADPH oxidase expression in the vascular tissues of HCHF rats. RBPH increased plasma nitrate/nitrite level and up-regulated eNOS expression in the aortas of HCHF-diet-fed rats, indicating that RBPH increased NO production. RBPH mitigate the deleterious effects of HCHF through potential mechanisms involving enhanced NO bioavailability, anti-ACE, anti-inflammatory and antioxidant properties. RBPH could be used as dietary supplements to minimize oxidative stress and vascular alterations triggered by MetS.

The effects of different schedules of total-body irradiation in heterotopic vascularized bone transplantation. An experimental study in the Lewis rat

International Nuclear Information System (INIS)

Gonzalez del Pino, J.; Benito, M.; Randolph, M.A.; Weiland, A.J.

1990-01-01

To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation

Blockade of Vascular Adhesion Protein-1 Inhibits Lymphocyte Infiltration in Rat Liver Allograft Rejection

OpenAIRE

Martelius, Timi; Salaspuro, Ville; Salmi, Marko; Krogerus, Leena; Höckerstedt, Krister; Jalkanen, Sirpa; Lautenschlager, Irmeli

2004-01-01

Vascular adhesion protein-1 (VAP-1) has been shown to mediate lymphocyte adhesion to endothelia at sites of inflammation, but its functional role in vivo has not been tested in any rodent model. Here we report the effects of VAP-1 blockade on rat liver allograft rejection. BN recipients of PVG liver allografts (known to develop acute rejection by day 7) were treated with 2 mg/kg anti-VAP-1 (a new anti-rat VAP-1 mAb 174–5) or isotype-matched irrelevant antibody (NS1) every other day (n = 6/gro...

MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

Energy Technology Data Exchange (ETDEWEB)

Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Aguado, Andrea [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Zhenyukh, Olha; Briones, Ana María [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Alonso, María Jesús [Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón (Spain); Vassallo, Dalton Valentim [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Health Science Center of Vitória-EMESCAM, Vitória, ES CEP 29045-402 (Brazil); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain)

2015-03-01

Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

A magnesium based phosphate binder reduces vascular calcification without affecting bone in chronic renal failure rats.

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Ellen Neven

Full Text Available The alternative phosphate binder calcium acetate/magnesium carbonate (CaMg effectively reduces hyperphosphatemia, the most important inducer of vascular calcification, in chronic renal failure (CRF. In this study, the effect of low dose CaMg on vascular calcification and possible effects of CaMg on bone turnover, a persistent clinical controversy, were evaluated in chronic renal failure rats. Adenine-induced CRF rats were treated daily with 185 mg/kg CaMg or vehicle for 5 weeks. The aortic calcium content and area% calcification were measured to evaluate the effect of CaMg. To study the effect of CaMg on bone remodeling, rats underwent 5/6th nephrectomy combined with either a normal phosphorus diet or a high phosphorus diet to differentiate between possible bone effects resulting from either CaMg-induced phosphate deficiency or a direct effect of Mg. Vehicle or CaMg was administered at doses of 185 and 375 mg/kg/day for 8 weeks. Bone histomorphometry was performed. Aortic calcium content was significantly reduced by 185 mg/kg/day CaMg. CaMg ameliorated features of hyperparathyroid bone disease. In CRF rats on a normal phosphorus diet, the highest CaMg dose caused an increase in osteoid area due to phosphate depletion. The high phosphorus diet combined with the highest CaMg dose prevented the phosphate depletion and thus the rise in osteoid area. CaMg had no effect on osteoblast/osteoclast or dynamic bone parameters, and did not alter bone Mg levels. CaMg at doses that reduce vascular calcification did not show any harmful effect on bone turnover.

The effects of angiotensin II receptor antagonist (candesartan on rat renal vascular resistance

Directory of Open Access Journals (Sweden)

Supatraviwat, J

2004-05-01

Full Text Available The present study aimed to investigate the action of angiotensin II (AII on renal perfusion pressure and renal vascular resistance using noncompetitive AT1-receptor antagonist (candesartan or CV 11974. Experiments were performed in isolated kidney of adult male Wistar rats. Kreb's Henseleit solution was perfused into the renal artery at the rate of 3.5 ml/min. This flow rate was designed in order to maintain renal perfusion pressure between 80-120 mm Hg. Dose-response relationship between perfusion flow rate and AII concentration were studied. Renal perfusion pressure in response to 1, 10 and 100 nM AII were increased from basal perfusion pressure of 94±8 mm Hg to 127±6, 157±12 and 190±16 mm Hg, respectively. Administration of perfusate containing 11.4 μM candesartan for 30 min had no effect on the basal perfusion pressure. However, this significantly reduced renal perfusion pressure in the presence of AII (1, 10 and 100 nM by 39%, 47% and 61%, (n=7, P<0.05 respectively. At the basal perfusion pressure, calculated renal vascular resistance was 27±2 mm Hg · min · ml-1. However, the vascular resistance were found to be 41±1, 45±2 and 47±2 mm Hg · min · ml-1 when 1, 10 and 100 nM AII were added. Moreover, this dose of candesartan also showed a significant decrease in renal vascular resistance at the corresponding doses of AII by 38%, 48% and 43%, (n=7, P<0.05 respectively. The higher dose of candesartan (22.7 μM completely inhibited the action of 1, 10 and 100 nM AII on renal vasoconstriction. These results may indicate that the action of AII on renal vascular resistance is via AT1-receptor, at least in rat isolated perfusion kidney.

The Effect of Scalp Point Cluster-Needling on Learning and Memory Function and Neurotransmitter Levels in Rats with Vascular Dementia

OpenAIRE

Yang, Junli; Litscher, Gerhard; Li, Haitao; Guo, Wenhai; Liang, Zhang; Zhang, Ting; Wang, Weihua; Li, Xiaoyan; Zhou, Yao; Zhao, Bing; Rong, Qi; Sheng, Zemin; Gaischek, Ingrid; Litscher, Daniela; Wang, Lu

2014-01-01

We observed the effect of scalp point cluster-needling treatment on learning and memory function and neurotransmitter levels in rats with vascular dementia (VD). Permanent ligation of the bilateral carotid arteries was used to create the VD rat model. A Morris water maze was used to measure the rats' learning and memory function, and the changes in neurotransmitter levels in the rats' hippocampus were analyzed. The results show that scalp point cluster-needling can increase the VD rat model's...

Ferulic acid alleviates symptoms of preeclampsia in rats by upregulating vascular endothelial growth factor.

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Gong, Weiyan; Wan, Jipeng; Yuan, Qing; Man, Quanzhan; Zhang, Xiaojing

2017-10-01

Preeclampsia is a complication affecting pregnant women worldwide, which leads to maternal and fetal morbidity and mortality. In this study, we evaluated the efficacy of ferulic acid (FA) on an N ω -nitro-L-arginine methyl ester hydrochloride (L-NAME) induced rat model of preeclampsia. L-NAME was administered to pregnant rats to induce preeclampsia. 48 rats were divided into three experimental groups (n=16 each): control group, preeclampsia group and preeclampsia with FA treatment (preeclampsia+FA). Physiological characteristics such as urine volume, total urine protein and blood pressure were assessed. Expressions levels of urinary nephrin and podocin mRNAs were analyzed by RT-PCR. Levels of renal vascular endothelial growth factor (VEGF), renal soluble fms-like tyrosine kinase-1 (sFlt-1) and serum placenta growth factor (PlGF) were also examined. Urine volume, total urine protein and blood pressure were markedly increased in preeclampsia group rats compared to control (Ppreeclampsia+FA group (Ppreeclampsia+FA group compared to preeclampsia rats (Ppreeclampsia symptoms in a rat preeclampsia model, supporting its potential value in treating preeclampsia. © 2017 John Wiley & Sons Australia, Ltd.

Leptin receptor blockade reduces intrahepatic vascular resistance and portal pressure in an experimental model of rat liver cirrhosis.

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Delgado, María Gabriela; Gracia-Sancho, Jordi; Marrone, Giusi; Rodríguez-Vilarrupla, Aina; Deulofeu, Ramon; Abraldes, Juan G; Bosch, Jaume; García-Pagán, Juan Carlos

2013-10-01

Increased hepatic vascular resistance mainly due to elevated vascular tone and to fibrosis is the primary factor in the development of portal hypertension in cirrhosis. Leptin, a hormone associated with reduction in nitric oxide bioavailability, vascular dysfunction, and liver fibrosis, is increased in patients with cirrhosis. We aimed at evaluating whether leptin influences the increased hepatic resistance in portal hypertension. CCl4-cirrhotic rats received the leptin receptor-blocker ObR antibody, or its vehicle, every other day for 1 wk. Hepatic and systemic hemodynamics were measured in both groups. Hepatic nitric oxide production and bioavailability, together with oxidative stress, nitrotyrosinated proteins, and liver fibrosis, were evaluated. In cirrhotic rats, leptin-receptor blockade significantly reduced portal pressure without modifying portal blood flow, suggesting a reduction in the intrahepatic resistance. Portal pressure reduction was associated with increased nitric oxide bioavailability and with decreased O2(-) levels and nitrotyrosinated proteins. No changes in systemic hemodynamics and liver fibrosis were observed. In conclusion, the present study shows that blockade of the leptin signaling pathway in cirrhosis significantly reduces portal pressure. This effect is probably due to a nitric oxide-mediated reduction in the hepatic vascular tone.

Resveratrol prevents high-fructose corn syrup-induced vascular insulin resistance and dysfunction in rats.

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Babacanoglu, C; Yildirim, N; Sadi, G; Pektas, M B; Akar, F

2013-10-01

Dietary intake of fructose and sucrose can cause development of metabolic and cardiovascular disorders. The consequences of high-fructose corn syrup (HFCS), a commonly consumed form of fructose and glucose, have poorly been examined. Therefore, in this study, we investigated whether HFCS intake (10% and 20% beverages for 12 weeks) impacts vascular reactivity to insulin and endothelin-1 in conjunction with insulin receptor substrate-1(IRS-1), endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) mRNA/proteins levels in aorta of rats. At challenge, we tested the effectiveness of resveratrol (28-30 mg/kg body weight/day) on outcomes of HFCS feeding. HFCS (20%) diet feeding increased plasma triglyceride, VLDL, cholesterol, insulin and glucose levels, but not body weights of rats. Impaired nitric oxide-mediated relaxation to insulin (10⁻⁹ to 3×10⁻⁶ M), and enhanced contraction to endothelin-1 (10⁻¹¹ to 10⁻⁸ M) were associated with decreased expression of IRS-1 and eNOS mRNA and protein, but increased expression of iNOS, in aortas of rats fed with HFCS. Resveratrol supplementation restored many features of HFCS-induced disturbances, probably by regulating eNOS and iNOS production. In conclusion, dietary HFCS causes vascular insulin resistance and endothelial dysfunction through attenuating IRS-1 and eNOS expressions as well as increasing iNOS in rats. Resveratrol has capability to recover HFCS-induced disturbances. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Dopamine induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages in rat C6 glioma

International Nuclear Information System (INIS)

Qin, Tian; Wang, Chenlong; Chen, Xuewei; Duan, Chenfan; Zhang, Xiaoyan; Zhang, Jing; Chai, Hongyan; Tang, Tian; Chen, Honglei; Yue, Jiang; Li, Ying; Yang, Jing

2015-01-01

Dopamine (DA), a monoamine catecholamine neurotransmitter with antiangiogenic activity, stabilizes tumor vessels in colon, prostate and ovarian cancers, thus increases chemotherapeutic efficacy. Here, in the rat C6 glioma models, we investigated the vascular normalization effects of DA and its mechanisms of action. DA (25, 50 mg/kg) inhibited tumor growth, while a precursor of DA (levodopa) prolonged the survival time of rats bearing orthotopic C6 glioma. DA improved tumor perfusion, with significant effects from day 3, and a higher level at days 5 to 7. In addition, DA decreased microvessel density and hypoxia-inducible factor-1α expression in tumor tissues, while increasing the coverage of pericyte. Conversely, an antagonist of dopamine receptor 2 (DR2) (eticlopride) but not DR1 (butaclamol) abrogated DA-induced tumor regression and vascular normalization. Furthermore, DA improved the delivery and efficacy of temozolomide therapy. Importantly, DA increased representative M1 markers (iNOS, CXCL9, etc.), while decreasing M2 markers (CD206, arginase-1, etc.). Depletion of macrophages by clodronate or zoledronic acid attenuated the effects of DA. Notably, DA treatment induced M2-to-M1 polarization in RAW264.7 cells and mouse peritoneal macrophages, and enhanced the migration of pericyte-like cells (10T1/2), which was reversed by eticlopride or DR2-siRNA. Such changes were accompanied by the downregulation of VEGF/VEGFR2 signaling. In summary, DA induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages. Thus, targeting the tumor microvasculature by DA represents a promising strategy for human glioma therapy. - Highlights: • Dopamine induces tumor growth inhibition and vascular normalization in rat C6 glioma. • Dopamine switches macrophage phenotype from M2 to M1. • Dopamine-induced vascular normalization is mediated by macrophage polarization. • Dopamine is a promising agent targeting the microvasculature in tumor

Dopamine induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages in rat C6 glioma

Energy Technology Data Exchange (ETDEWEB)

Qin, Tian; Wang, Chenlong; Chen, Xuewei; Duan, Chenfan; Zhang, Xiaoyan [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Zhang, Jing [Animal Experimental Center of Wuhan University, Wuhan 430071 (China); Chai, Hongyan [Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan 430071 (China); Tang, Tian [Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Chen, Honglei [Department of Pathology and Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yue, Jiang [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Li, Ying, E-mail: lyying0@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

2015-07-15

Dopamine (DA), a monoamine catecholamine neurotransmitter with antiangiogenic activity, stabilizes tumor vessels in colon, prostate and ovarian cancers, thus increases chemotherapeutic efficacy. Here, in the rat C6 glioma models, we investigated the vascular normalization effects of DA and its mechanisms of action. DA (25, 50 mg/kg) inhibited tumor growth, while a precursor of DA (levodopa) prolonged the survival time of rats bearing orthotopic C6 glioma. DA improved tumor perfusion, with significant effects from day 3, and a higher level at days 5 to 7. In addition, DA decreased microvessel density and hypoxia-inducible factor-1α expression in tumor tissues, while increasing the coverage of pericyte. Conversely, an antagonist of dopamine receptor 2 (DR2) (eticlopride) but not DR1 (butaclamol) abrogated DA-induced tumor regression and vascular normalization. Furthermore, DA improved the delivery and efficacy of temozolomide therapy. Importantly, DA increased representative M1 markers (iNOS, CXCL9, etc.), while decreasing M2 markers (CD206, arginase-1, etc.). Depletion of macrophages by clodronate or zoledronic acid attenuated the effects of DA. Notably, DA treatment induced M2-to-M1 polarization in RAW264.7 cells and mouse peritoneal macrophages, and enhanced the migration of pericyte-like cells (10T1/2), which was reversed by eticlopride or DR2-siRNA. Such changes were accompanied by the downregulation of VEGF/VEGFR2 signaling. In summary, DA induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages. Thus, targeting the tumor microvasculature by DA represents a promising strategy for human glioma therapy. - Highlights: • Dopamine induces tumor growth inhibition and vascular normalization in rat C6 glioma. • Dopamine switches macrophage phenotype from M2 to M1. • Dopamine-induced vascular normalization is mediated by macrophage polarization. • Dopamine is a promising agent targeting the microvasculature in tumor

The zinc transporter ZIP12 regulates the pulmonary vascular response to chronic hypoxia.

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Zhao, Lan; Oliver, Eduardo; Maratou, Klio; Atanur, Santosh S; Dubois, Olivier D; Cotroneo, Emanuele; Chen, Chien-Nien; Wang, Lei; Arce, Cristina; Chabosseau, Pauline L; Ponsa-Cobas, Joan; Frid, Maria G; Moyon, Benjamin; Webster, Zoe; Aldashev, Almaz; Ferrer, Jorge; Rutter, Guy A; Stenmark, Kurt R; Aitman, Timothy J; Wilkins, Martin R

2015-08-20

The typical response of the adult mammalian pulmonary circulation to a low oxygen environment is vasoconstriction and structural remodelling of pulmonary arterioles, leading to chronic elevation of pulmonary artery pressure (pulmonary hypertension) and right ventricular hypertrophy. Some mammals, however, exhibit genetic resistance to hypoxia-induced pulmonary hypertension. We used a congenic breeding program and comparative genomics to exploit this variation in the rat and identified the gene Slc39a12 as a major regulator of hypoxia-induced pulmonary vascular remodelling. Slc39a12 encodes the zinc transporter ZIP12. Here we report that ZIP12 expression is increased in many cell types, including endothelial, smooth muscle and interstitial cells, in the remodelled pulmonary arterioles of rats, cows and humans susceptible to hypoxia-induced pulmonary hypertension. We show that ZIP12 expression in pulmonary vascular smooth muscle cells is hypoxia dependent and that targeted inhibition of ZIP12 inhibits the rise in intracellular labile zinc in hypoxia-exposed pulmonary vascular smooth muscle cells and their proliferation in culture. We demonstrate that genetic disruption of ZIP12 expression attenuates the development of pulmonary hypertension in rats housed in a hypoxic atmosphere. This new and unexpected insight into the fundamental role of a zinc transporter in mammalian pulmonary vascular homeostasis suggests a new drug target for the pharmacological management of pulmonary hypertension.

Adventitial gene transfer of catalase attenuates angiotensin II-induced vascular remodeling.

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Liu, Cun-Fei; Zhang, Jia; Shen, Kai; Gao, Ping-Jin; Wang, Hai-Ya; Jin, Xin; Meng, Chao; Fang, Ning-Yuan

2015-04-01

Vascular adventitia and adventitia‑derived reactive oxygen species (ROS) contribute to vascular remodeling following vascular injury. A previous ex vivo study in adventitial fibroblasts showed that catalase, one of most important anti‑oxide enzymes, was downregulated by angiotensin II (AngII). The aim of the present study was to investigate whether adventitial gene transfer of catalase affects AngII‑induced vascular remodeling in vivo. Adenoviruses co‑expressing catalase and enhanced green fluorescent protein (eGFP) or expressing eGFP only were applied to the adventitial surface of common carotid arteries of Sprague‑Dawley rats. Alzet minipumps administering AngII (0.75 mg/kg/day) were then implanted subcutaneously for 14 days. Systolic blood pressure and biological parameters of vascular remodeling were measured in each group. Adventitial fibroblasts were cultured and p38 mitogen‑activated protein kinase (MAPK) phosphorylation was measured using western blot analysis. The results showed that adventitial gene transfer of catalase had no effect on AngII‑induced systolic blood pressure elevation. However, catalase adenovirus transfection significantly inhibited AngII‑induced media hypertrophy compared with that of the control virus (Padventitial α‑smooth muscle actin expression. Furthermore, catalase transfection significantly inhibited the AngII‑induced increase in p38MAPK phosphorylation. In conclusion, the results of the present study demonstrated that adventitial gene transfer of catalase significantly attenuated AngII‑induced vascular remodeling in rats via inhibition of adventitial p38MAPK phosphorylation.

Stimulation of DNA synthesis in cultured rat alveolar type II cells

International Nuclear Information System (INIS)

Leslie, C.C.; McCormick-Shannon, K.; Robinson, P.C.; Mason, R.J.

1985-01-01

Restoration of the alveolar epithelium after injury is thought to be dependent on the proliferation of alveolar type II cells. To understand the factors that may be involved in promoting type II cell proliferation in vivo, we determined the effect of potential mitogens and culture substrata on DNA synthesis in rat alveolar type II cells in primary culture. Type II cells cultured in basal medium containing 10% fetal bovine serum (FBS) exhibited essentially no DNA synthesis. Factors that stimulated 3 H-thymidine incorporation included cholera toxin, epidermal growth factor, and rat serum. The greatest degree of stimulation was achieved by plating type II cells on an extracellular matrix prepared from bovine corneal endothelial cells and then by culturing the pneumocytes in medium containing rat serum, cholera toxin, insulin, and epidermal growth factor. Under conditions of stimulation of 3 H-thymidine incorporation there was an increased DNA content per culture dish but no increase in cell number. The ability of various culture conditions to promote DNA synthesis in type II cells was verified by autoradiography. Type II cells were identified by the presence of cytoplasmic inclusions, which were visualized by tannic acid staining before autoradiography. These results demonstrate the importance of soluble factors and culture substratum in stimulating DNA synthesis in rat alveolar type II cells in primary culture

Differential Gene Expression of Primary Cultured Lymphatic and Blood Vascular Endothelial Cells

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Gregory M. Nelson

2007-12-01

Full Text Available Blood vascular endothelial cells (BECs and the developmentally related lymphatic endothelial cells (LECs create complementary, yet distinct vascular networks. Each endothelial cell type interacts with flowing fluid and circulating cells, yet each vascular system has evolved specialized gene expression programs and thus both cell types display different phenotypes. BECs and LECs express distinct genes that are unique to their specific vascular microenvironment. Tumors also take advantage of the molecules that are expressed in these vascular systems to enhance their metastatic potential. We completed transcriptome analyses on primary cultured LECs and BECs, where each comparative set was isolated from the same individual. Differences were resolved in the expression of several major categories, such as cell adhesion molecules (CAMs, cytokines, cytokine receptors. We have identified new molecules that are associated with BECs (e.g., claudin-9, CXCL11, neurexin-1, neurexin-2, the neuronal growth factor regulator-1 and LECs (e.g., claudin-7, CD58, hyaluronan and proteoglycan link protein 1 (HAPLN1, the poliovirus receptor-related 3 molecule that may lead to novel therapeutic treatments for diseases of lymphatic or blood vessels, including metastasis of cancer to lymph nodes or distant organs.

Sodium thiosulfate protects brain in rat model of adenine induced vascular calcification.

Science.gov (United States)

Subhash, N; Sriram, R; Kurian, Gino A

2015-11-01

Vascular bed calcification is a common feature of ends stage renal disease that may lead to a complication in cardiovascular and cerebrovascular beds, which is a promoting cause of myocardial infarction, stroke, dementia and aneurysms. Sodium thiosulfate (STS) due to its multiple properties such as antioxidant and calcium chelation has been reported to prevent vascular calcification in uremic rats, without mentioning its impact on cerebral function. Moreover, the previous studies have not explored the effect of STS on the mitochondrial dysfunction, one of the main pathophysiological features associated with the disease and the main site for STS metabolism. The present study addresses this limitation by using a rat model where 0.75% adenine was administered to induce vascular calcification and 400 mg/kg b wt. of STS was given as preventive and curative agent. The blood and urine chemistries along with histopathology of aorta confirms the renal protective effect of STS in two modes of administration. The brain oxidative stress assessment was made through TBARS level, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, found to be in the near normal level. STS administration not only reduced the mitochondrial oxidative stress (measured by TBARS, SOD, GPx and CAT) but also preserved the mitochondrial respiratory enzyme activities (NADH dehydrogenase, Succinate dehydrogenase and Malate dehydrogenase) and its physiology (measured by P/O ratio and RCR). In fact, the protective effect of STS was prominent, when it was administered as a curative agent, where low H2S and high thiosulfate level was observed along with low cystathionine β synthase activity, confirms thiosulfate mediated renal protection. In conclusion, STS when given after induction of calcification is protective to the brain by preserving its mitochondria, compared to the treatment given concomitantly. Copyright © 2015 Elsevier Ltd. All rights reserved.

Palm Tocotrienol-Rich Fraction Improves Vascular Proatherosclerotic Changes in Hyperhomocysteinemic Rats

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Ku-Zaifah Norsidah

2013-01-01

Full Text Available This study investigated the effects of palm tocotrienol-rich fraction (TRF on aortic proatherosclerotic changes in rats fed with a high methionine diet. Forty-two male Wistar rats were divided into six groups. The first group was the control (fed with a basal diet. Another five groups were fed with 1% methionine diet for 10 weeks. From week 6 onward, folate (8 mg/kg diet or palm TRF (30, 60, and 150 mg/kg diets was added into the diet of the last four rat groups, respectively. The high methionine diet raised the plasma total homocysteine and aortic lipid peroxidation, which were reduced by the palm TRF and folate supplementations. Plasma nitric oxide was reduced in the high methionine group compared to the control (3.72±0.57 versus 6.65±0.53 μmol/L, P<0.05, which reduction was reversed by the palm TRF (60 and 150 mg/kg and folate supplementations. The increased aortic vascular cell adhesion molecule-1 expression in the methionine group (2.58±0.29 was significantly reduced by the folate (1.38±0.18 and palm TRF at 150 mg/kg (1.19±0.23. Palm TRF was comparable to folate in reducing high methionine diet-induced plasma hyperhomocysteinemia, aortic oxidative stress, and inflammatory changes in rats.

Decrease of Perivascular Adipose Tissue Browning Is Associated With Vascular Dysfunction in Spontaneous Hypertensive Rats During Aging

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Ling-Ran Kong

2018-04-01

Full Text Available Functional perivascular adipose tissue (PVAT is necessary to maintain vascular physiology through both mechanical support and endocrine or paracrine ways. PVAT shows a brown adipose tissue (BAT-like feature and the browning level of PVAT is dependent on the anatomic location and species. However, it is not clear whether PVAT browning is involved in the vascular tone regulation in spontaneously hypertensive rats (SHRs. In the present study, we aimed to illustrate the effect of aging on PVAT browning and subsequent vasomotor reaction in SHRs. Herein we utilized histological staining and western blot to detect the characteristics of thoracic PVAT (tPVAT in 8-week-old and 16-week-old SHR and Wistar-Kyoto (WKY rats. We also detected vascular reactivity analysis to determine the effect of tPVAT on vasomotor reaction during aging. The results showed that tPVAT had a similar phenotype to BAT, including smaller adipocyte size and positive uncoupling protein-1 (UCP1 staining. Interestingly, the tPVAT of 8-week-old SHR showed increased BAT phenotypic marker expression compared to WKY, whereas the browning level of tPVAT had a more dramatic decrease from 8 to 16 weeks of age in SHR than age-matched WKY rats. The vasodilation effect of tPVAT on aortas had no significant difference in 8-week-old WKY and SHR, whereas this effect is obviously decreased in 16-week-old SHR compared to WKY. In contrast, tPVAT showed a similar vasoconstriction effect in 8- or 16-week-old WKY and SHR rats. Moreover, we identified an important vasodilator adenosine, which regulates adipocyte browning and may be a potential PVAT-derived relaxing factor. Adenosine is dramatically decreased from 8 to 16 weeks of age in the tPVAT of SHR. In summary, aging is associated with a decrease of tPVAT browning and adenosine production in SHR rats. These may result in attenuated vasodilation effect of the tPVAT in SHR during aging.

Panax ginseng extract attenuates neuronal injury and cognitive deficits in rats with vascular dementia induced by chronic cerebral hypoperfusion

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Jun-De Zhu

2018-01-01

Full Text Available Panax ginseng is a slow-growing perennial plant. Panax ginseng extract has numerous biological activities, including antitumor, anti-inflammatory and antistress activities. Panax ginseng extract also has a cognition-enhancing effect in rats with alcohol-induced memory impairment. In this study, we partially occluded the bilateral carotid arteries in the rat to induce chronic cerebral hypoperfusion, a well-known model of vascular dementia. The rats were then intragastrically administered 50 or 100 mg/kg Panax ginseng extract. Morris water maze and balance beam tests were used to evaluate memory deficits and motor function, respectively. Protein quantity was used to evaluate cholinergic neurons. Immunofluorescence staining was used to assess the number of glial fibrillary acidic protein-positive cells. Western blot assay was used to evaluate protein levels of vascular endothelial growth factor, basic fibroblast growth factor, Bcl-2 and Bax. Treatment with Panax ginseng extract for 8 weeks significantly improved behavioral function and increased neuronal density and VEGF and bFGF protein expression in the hippocampal CA3 area. Furthermore, Panax ginseng extract reduced the number of glial fibrillary acidic protein-immunoreactive cells, and it decreased apoptosis by upregulating Bcl-2 and downregulating Bax protein expression. The effect of Panax ginseng extract was dose-dependent and similar to that of nimodipine, a commonly used drug for the treatment of vascular dementia. These findings suggest that Panax ginseng extract is neuroprotective against vascular dementia induced by chronic cerebral hypoperfusion, and therefore might have therapeutic potential for preventing and treating the disease.

Prophylactic effects of elastin peptide derived from the bulbus arteriosus of fish on vascular dysfunction in spontaneously hypertensive rats.

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Takemori, Kumiko; Yamamoto, Ei; Ito, Hiroyuki; Kometani, Takashi

2015-01-01

To determine the prophylactic effects of an elastin peptide derived from the bulbus arteriosus of bonitos and prolylglycine (PG), a degradation product of elastin peptide, on vascular dysfunction in spontaneously hypertensive rats (SHRs). Male 15-week-old SHR/Izm rats were fed without (control group) or with elastin peptide (1 g/kg body weight) for 5 weeks (EP group), or were infused via an osmotic mini-pump for 4 weeks with PG (PG group) or saline (control group). Using thoracic aortas, we assessed endothelial changes by scanning electron microscopy. Vascular reactivity (contraction and relaxation) and pressure-induced distension was compared. mRNA production levels of endothelial nitric oxide synthase (eNOS) and intercellular adhesion molecule-1 (ICAM-1) were investigated by real-time-polymerase chain reaction. Aortas of the EP group displayed limited endothelial damage compared with that in the control group. Under treatment of SHRs with elastin peptide, the effect of phenylephrine returned closer to the normal level observed in normotensive Wistar-Kyoto (WKY/Izm) rats. mRNA production of eNOS (but not ICAM-1) was greater in the EP group than in the control group. Endothelial damage was suppressed and pressure-induced vascular distension was greater in the PG group than in the corresponding control group. These results suggest that elastin peptide from bonitos elicits prophylactic affects hypertension-associated vascular dysfunction by targeting the eNOS signaling pathway. PG may be a key mediator of the beneficial effects of elastin peptide. Copyright © 2014 Elsevier Inc. All rights reserved.

Advanced Maternal Age Worsens Postpartum Vascular Function

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Jude S. Morton

2017-06-01

Full Text Available The age at which women experience their first pregnancy has increased throughout the decades. Pregnancy has an important influence on maternal short- and long-term cardiovascular outcomes. Pregnancy at an advanced maternal age increases maternal risk of gestational diabetes, preeclampsia, placenta previa and caesarian delivery; complications which predict worsened cardiovascular health in later years. Aging also independently increases the risk of cardiovascular disease; therefore, combined risk in women of advanced maternal age may lead to detrimental cardiovascular outcomes later in life. We hypothesized that pregnancy at an advanced maternal age would lead to postpartum vascular dysfunction. We used a reproductively aged rat model to investigate vascular function in never pregnant (virgin, previously pregnant (postpartum and previously mated but never delivered (nulliparous rats at approximately 13.5 months of age (3 months postpartum or equivalent. Nulliparous rats, in which pregnancy was spontaneously lost, demonstrated significantly reduced aortic relaxation responses (methylcholine [MCh] Emax: 54.2 ± 12.6% vs. virgin and postpartum rats (MCh Emax: 84.8 ± 3.5% and 84.7 ± 3.2% respectively; suggesting pregnancy loss causes a worsened vascular pathology. Oxidized LDL reduced relaxation to MCh in aorta from virgin and postpartum, but not nulliparous rats, with an increased contribution of the LOX-1 receptor in the postpartum group. Further, in mesenteric arteries from postpartum rats, endothelium-derived hyperpolarization (EDH-mediated vasodilation was reduced and a constrictive prostaglandin effect was apparent. In conclusion, aged postpartum rats exhibited vascular dysfunction, while rats which had pregnancy loss demonstrated a distinct vascular pathology. These data demonstrate mechanisms which may lead to worsened outcomes at an advanced maternal age; including early pregnancy loss and later life cardiovascular dysfunction.

Effects of High Glucose on Vascular Endothelial Growth Factor Synthesis and Secretion in Aortic Vascular Smooth Muscle Cells from Obese and Lean Zucker Rats

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Mariella Trovati

2012-07-01

Full Text Available Type 1 diabetes is characterized by insulin deficiency, type 2 by both insulin deficiency and insulin resistance: in both conditions, hyperglycaemia is accompanied by an increased cardiovascular risk, due to increased atherosclerotic plaque formation/instabilization and impaired collateral vessel formation. An important factor in these phenomena is the Vascular Endothelial Growth Factor (VEGF, a molecule produced also by Vascular Smooth Muscle Cells (VSMC. We aimed at evaluating the role of high glucose on VEGF-A₁₆₄ synthesis and secretion in VSMC from lean insulin-sensitive and obese insulin-resistant Zucker rats (LZR and OZR. In cultured aortic VSMC from LZR and OZR incubated for 24 h with D-glucose (5.5, 15 and 25 mM or with the osmotic controls L-glucose and mannitol, we measured VEGF-A₁₆₄ synthesis (western, blotting and secretion (western blotting and ELISA. We observed that: (i D-glucose dose-dependently increases VEGF-A₁₆₄ synthesis and secretion in VSMC from LZR and OZR (n = 6, ANOVA p = 0.002–0.0001; (ii all the effects of 15 and 25 mM D-glucose are attenuated in VSMC from OZR vs. LZR (p = 0.0001; (iii L-glucose and mannitol reproduce the VEGF-A₁₆₄ modulation induced by D-glucose in VSMC from both LZR and OZR. Thus, glucose increases via an osmotic mechanism VEGF synthesis and secretion in VSMC, an effect attenuated in the presence of insulin resistance.

ELECTROACUPUNCTURE AT THE WANGU ACUPOINT SUPPRESSES EXPRESSION OF INFLAMMATORY CYTOKINES IN THE HIPPOCAMPUS OF RATS WITH VASCULAR DEMENTIA.

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Fang, Yanan; Sui, Rubo

2016-01-01

Vascular dementia (VD) is the most frequent psychiatric complication of stroke, and is often difficult to treat. Incidence rate of vascular cognition impairment is still 70% after stroke in one year (Sui R et al.2011). Stroke patients with VD suffer from a higher mortality rate and have worse functional outcomes and quality of life. However, despite the extensive literatures on this topic, there is no agreement on the causal mechanisms and effective therapy for VD. The objective of this study is to examine if electroacupuncture at the Wangu acupoint (GB 12), whose position is similar to the cerebellar fastigial nucleus, could reduce inflammatory cytokines in the hippocampus of rats with vascular dementia (VD). The 54 healthy, male, Sprague-Dawley (SD) rats, 9 months old, and of clean grade (300-450) g, were randomly divided into three groups: sham surgery group, VD group and electro-acupuncture group. The ethology scores of VD rats were evaluated and the mRNA expressions of inflammatory cytokines (TNF-α, IL-6 and IL-1β) in the hippocampus were assessed and the hippocampal tissues were observed by hematoxylin-eosin staining. Compared with the VD group, in the electroacupuncture group, the rats' learning ability improved significantly and the mRNA expression of TNF-α, IL-6 and IL-1β decreased. Simultaneously, the damage extent of nerve cells in the hippocampal tissues decreased, with their morphology recovered to nearly normal. Electro-acupuncture at the Wangu acupoint can decrease the levels of inflammatory cytokines in the hippocampus, reduce the damage extent of nerve cells in the hippocampus, and thus provide a new neuroprotective method in VD.

Three-dimensional Hessian matrix-based quantitative vascular imaging of rat iris with optical-resolution photoacoustic microscopy in vivo

Science.gov (United States)

Zhao, Huangxuan; Wang, Guangsong; Lin, Riqiang; Gong, Xiaojing; Song, Liang; Li, Tan; Wang, Wenjia; Zhang, Kunya; Qian, Xiuqing; Zhang, Haixia; Li, Lin; Liu, Zhicheng; Liu, Chengbo

2018-04-01

For the diagnosis and evaluation of ophthalmic diseases, imaging and quantitative characterization of vasculature in the iris are very important. The recently developed photoacoustic imaging, which is ultrasensitive in imaging endogenous hemoglobin molecules, provides a highly efficient label-free method for imaging blood vasculature in the iris. However, the development of advanced vascular quantification algorithms is still needed to enable accurate characterization of the underlying vasculature. We have developed a vascular information quantification algorithm by adopting a three-dimensional (3-D) Hessian matrix and applied for processing iris vasculature images obtained with a custom-built optical-resolution photoacoustic imaging system (OR-PAM). For the first time, we demonstrate in vivo 3-D vascular structures of a rat iris with a the label-free imaging method and also accurately extract quantitative vascular information, such as vessel diameter, vascular density, and vascular tortuosity. Our results indicate that the developed algorithm is capable of quantifying the vasculature in the 3-D photoacoustic images of the iris in-vivo, thus enhancing the diagnostic capability of the OR-PAM system for vascular-related ophthalmic diseases in vivo.

Effect of adipose-derived mesenchymal stem cell transplantation on vascular calcification in rats with adenine-induced kidney disease

OpenAIRE

Yokote, Shinya; Katsuoka, Yuichi; Yamada, Akifumi; Ohkido, Ichiro; Yokoo, Takashi

2017-01-01

Previous studies have investigated the use of mesenchymal stem cells (MSCs) to treat damaged kidneys. However, the effect of adipose-derived MSCs (ASCs) on vascular calcification in chronic kidney disease (CKD) is still poorly understood. In the present study, we explored the potential of ASCs for the treatment of CKD and vascular calcification. CKD was induced in male Sprague-Dawley rats by feeding them a diet containing 0.75% adenine for 4 weeks. ASCs transplantation significantly reduced s...

Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

International Nuclear Information System (INIS)

Eissa, Laila A.; Smith, Sylvia B.; El-sherbeny, Amira A.

2006-01-01

Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

Effects of prolonged ingestion of epigallocatechin gallate on diabetes type 1-induced vascular modifications in the erectile tissue of rats.

Science.gov (United States)

Lombo, C; Morgado, C; Tavares, I; Neves, D

2016-07-01

Diabetes Mellitus type 1 is a metabolic disease that predisposes to erectile dysfunction, partly owing to structural and molecular changes in the corpus cavernosum (CC) vessels. The aim of this study was to determine the effects of early treatment with the antioxidant epigallocatechin gallate (EGCG) in cavernous diabetes-induced vascular modifications. Diabetes was induced in two groups of young Wistar rats; one group was treated with EGCG for 10 weeks. A reduction in smooth muscle content was observed in the CC of diabetic rats, which was significantly attenuated with EGCG consumption. No differences were observed among groups, neither in the expression of VEGF assayed by western blotting nor in the immunofluorescent labeling of vascular endothelial growth factor (VEGF) and its receptors (VEGFR1 and VEGFR2). VEGFR2 was restricted to the endothelium, whereas VEGF and VEGFR1 co-localized in the smooth muscle layer. With regard to the Angiopoietin/Tie-2 system, no quantitative differences in Angiopoietin 1 were observed among the experimental groups. Ang1 localization was restricted to the smooth muscle layer, and receptor Tie2 and Angiopoietin 2 were both expressed in the endothelium. In brief, our results suggest that EGCG consumption prevented diabetes-induced loss of cavernous smooth muscle but does not affect vascular growth factor expression in young rats.

Erythroid differentiation and commitment in rat erythroleukemia cells with hypertonic culture conditions.

OpenAIRE

Yamaguchi, Y; Kluge, N; Ostertag, W; Furusawa, M

1981-01-01

Cell cultures of 7,12-dimethylbenz[a]anthracene-induced rat erythroleukemia can be stimulated to synthesize hemoglobin when cultured in hypertonic media. During hypertonic treatment the intracellular osmotic conditions immediately readjust to those of the extracellular medium. None of the Friend virus-induced mouse erythroleukemia cell lines was inducible for differentiation with the same hypertonic culture conditions used for rat cells. Earliest commitment to erythroid terminal differentiati...

Hypoxia preferentially destroys GABAergic neurons in developing rat neocortex explants in culture

NARCIS (Netherlands)

Romijn, H. J.; Ruijter, J. M.; Wolters, P. S.

1988-01-01

The hypothesis that hypoxic ischemia before or during the human birth process preferentially destroys GABAergic nerve cells, particularly in the neocortex, was tested in a tissue culture model system. To that end, rat neocortex explants dissected from 6-day-old rat pups and cultured to a

Antioxidant treatment alters peripheral vascular dysfunction induced by postnatal glucocorticoid therapy in rats.

Directory of Open Access Journals (Sweden)

Emilio A Herrera

2010-02-01

Full Text Available Postnatal glucocorticoid therapy in premature infants diminishes chronic lung disease, but it also increases the risk of hypertension in adulthood. Since glucocorticoid excess leads to overproduction of free radicals and endothelial dysfunction, this study tested the hypothesis that adverse effects on cardiovascular function of postnatal glucocorticoids are secondary to oxidative stress. Therefore, combined postnatal treatment of glucocorticoids with antioxidants may diminish unwanted effects.Male rat pups received a course of dexamethasone (Dex, or Dex with vitamins C and E (DexCE, on postnatal days 1-6 (P1-6. Controls received vehicle (Ctrl or vehicle with vitamins (CtrlCE. At P21, femoral vascular reactivity was determined via wire myography. Dex, but not DexCE or CtrlCE, increased mortality relative to Ctrl (81.3 versus 96.9 versus 90.6 versus 100% survival, respectively; P<0.05. Constrictor responses to phenylephrine (PE and thromboxane were enhanced in Dex relative to Ctrl (84.7+/-4.8 versus 67.5+/-5.7 and 132.7+/-4.9 versus 107.0+/-4.9% Kmax, respectively; P<0.05; effects that were diminished in DexCE (58.3+/-7.5 and 121.1+/-4.3% Kmax, respectively; P<0.05. Endothelium-dependent dilatation was depressed in Dex relative to Ctrl (115.3+/-11.9 versus 216.9+/-18.9, AUC; P<0.05; however, this effect was not restored in DexCE (68.3+/-8.3, AUC. Relative to Ctrl, CtrlCE alone diminished PE-induced constriction (43.4+/-3.7% Kmax and the endothelium-dependent dilatation (74.7+/-8.7 AUC; P<0.05.Treatment of newborn rats with dexamethasone has detrimental effects on survival and peripheral vasoconstrictor function. Coadministration of dexamethasone with antioxidant vitamins improves survival and partially restores vascular dysfunction. Antioxidant vitamins alone affect peripheral vascular function.

Rat embryonic palatal shelves respond to TCDD in organ culture

International Nuclear Information System (INIS)

Abbott, B.D.; Birnbaum, L.S.

1990-01-01

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), a highly toxic environmental contaminant, is teratogenic in mice, inducing cleft palate (CP) and hydronephrosis at doses which are not overtly maternally or embryo toxic. Palatal shelves of embryonic mice respond to TCDD, both in vivo and in organ culture, with altered differentiation of medial epithelial cells. By contrast, in the rat TCDD produces substantial maternal, embryonic, and fetal toxicity, including fetal lethality, with few malformations. In this study the possible effects of maternal toxicity on induction of cleft palate were eliminated by exposure of embryonic rat palatal shelves in organ culture. The shelves were examined for specific TCDD-induced alterations in differentiation of the medial cells. On Gestation Day (GD) 14 or 15 palatal shelves from embryonic F344 rats were placed in organ culture for 2 to 3 days (IMEM:F12 medium, 5% FBS, 0.1% DMSO) containing 0, 1 x 10(-8), 1 x 10(-9), 1 x 10(-10), or 5 x 10(-11) M TCDD. The medial epithelial peridermal cells degenerated on shelves exposed to control media or 5 x 10(-11) M TCDD. Exposure to 10(-10), 10(-9), and 10(-8) M TCDD inhibited this degeneration in 20, 36, and 60% of the shelves, respectively, and was statistically significant at the two highest doses. A normally occurring decrease in [3H]TdR incorporation was inhibited in some GD 15 shelves cultured with 10(-10) and 10(-9) M TCDD. The medial cells of TCDD-exposed shelves continued to express high levels of immunohistochemically detected EGF receptors. The altered differentiation of rat medial epithelium is similar to that reported for TCDD-exposed mouse medial cells in vivo and in vitro. However, in order to obtain these responses, the cultured rat shelves require much higher concentrations of TCDD than the mouse shelves

ITE and TCDD differentially regulate the vascular remodeling of rat placenta via the activation of AhR.

Science.gov (United States)

Wu, Yanming; Chen, Xiao; Zhou, Qian; He, Qizhi; Kang, Jiuhong; Zheng, Jing; Wang, Kai; Duan, Tao

2014-01-01

Vascular remodeling in the placenta is essential for normal fetal development. The previous studies have demonstrated that in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, an environmental toxicant) induces the intrauterine fetal death in many species via the activation of aryl hydrocarbon receptor (AhR). In the current study, we compared the effects of 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) and TCDD on the vascular remodeling of rat placentas. Pregnant rats on gestational day (GD) 15 were randomly assigned into 5 groups, and were exposed to a single dose of 1.6 and 8.0 mg/kg body weight (bw) ITE, 1.6 and 8.0 µg/kg bw TCDD, or an equivalent volume of the vehicle, respectively. The dams were sacrificed on GD20 and the placental tissues were gathered. The intrauterine fetal death was observed only in 8.0 µg/kg bw TCDD-exposed group and no significant difference was seen in either the placental weight or the fetal weight among all these groups. The immunohistochemical and histological analyses revealed that as compared with the vehicle-control, TCDD, but not ITE, suppressed the placental vascular remodeling, including reduced the ratio of the placental labyrinth zone to the basal zone thickness (at least 0.71 fold of control), inhibited the maternal sinusoids dilation and thickened the trophoblastic septa. However, no marked difference was observed in the density of fetal capillaries in the labyrinth zone among these groups, although significant differences were detected in the expression of angiogenic growth factors between ITE and TCDD-exposed groups, especially Angiopoietin-2 (Ang-2), Endoglin, Interferon-γ (IFN-γ) and placenta growth factor (PIGF). These results suggest ITE and TCDD differentially regulate the vascular remodeling of rat placentas, as well as the expression of angiogenic factors and their receptors, which in turn may alter the blood flow in the late gestation and partially resulted in

Effects of Sucroferric Oxyhydroxide Compared to Lanthanum Carbonate and Sevelamer Carbonate on Phosphate Homeostasis and Vascular Calcifications in a Rat Model of Chronic Kidney Failure

Directory of Open Access Journals (Sweden)

Olivier Phan

2015-01-01

Full Text Available Elevated serum phosphorus, calcium, and fibroblast growth factor 23 (FGF23 levels are associated with cardiovascular disease in chronic renal disease. This study evaluated the effects of sucroferric oxyhydroxide (PA21, a new iron-based phosphate binder, versus lanthanum carbonate (La and sevelamer carbonate (Se, on serum FGF23, phosphorus, calcium, and intact parathyroid hormone (iPTH concentrations, and the development of vascular calcification in adenine-induced chronic renal failure (CRF rats. After induction of CRF, renal function was significantly impaired in all groups: uremic rats developed severe hyperphosphatemia, and serum iPTH increased significantly. All uremic rats (except controls then received phosphate binders for 4 weeks. Hyperphosphatemia and increased serum iPTH were controlled to a similar extent in all phosphate binder-treatment groups. Only sucroferric oxyhydroxide was associated with significantly decreased FGF23. Vascular calcifications of the thoracic aorta were decreased by all three phosphate binders. Calcifications were better prevented at the superior part of the thoracic and abdominal aorta in the PA21 treated rats. In adenine-induced CRF rats, sucroferric oxyhydroxide was as effective as La and Se in controlling hyperphosphatemia, secondary hyperparathyroidism, and vascular calcifications. The role of FGF23 in calcification remains to be confirmed.

Cytoarchitecture in cultured rat neocortex explants

NARCIS (Netherlands)

de Jong, B. M.; Ruijter, J. M.; Romijn, H. J.

1988-01-01

Neocortex explants obtained from 6-day-old rat pups and cultured in a serum-free medium from 5 hr to 13 days in vitro (DIV) show preservation of cytoarchitectural characteristics. Major changes in the size of the explants and their layers occur during the first 2 DIV. A radial arrangement of neurons

Subarachnoid hemorrhage enhances endothelin receptor expression and function in rat cerebral arteries

DEFF Research Database (Denmark)

Hansen-Schwartz, Jacob; Hoel, Natalie Løvland; Zhou, Mingfang

2003-01-01

OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood into the prechiasm......OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood...... into the prechiasmatic cistern. After 2 days, the middle cerebral artery, basilar artery, and posterior communicating artery were harvested. Pharmacological studies were performed in vitro, and levels of messenger ribonucleic acid (mRNA) were quantified in real-time reverse transcriptase-polymerase chain reaction assays....... RESULTS: In the middle cerebral artery and basilar artery from rats with induced SAH, enhanced biphasic responses to ET-1 were observed. The -log(50% effective concentration) value for the high-affinity phase was approximately 12, compared with approximately 8.5 for sham-operated animals...

Post-stroke gaseous hypothermia increases vascular density but not neurogenesis in the ischemic penumbra of aged rats

DEFF Research Database (Denmark)

Sandu, Raluca Elena; Uzoni, Adriana; Ciobanu, Ovidiu

2016-01-01

of several genes involved in protein degradation, thereby leading to better preservation of infarcted tissue. Further, hypothermia increased the density of newly formed blood vessels in the peri-lesional cortex did not enhance neurogenesis in the infarcted area of aged rats. Likewise, there was improved......-PCR and immunofluorescence, we assessed infarct size, vascular density, neurogenesis and as well as the expression of genes coding for proteasomal proteins as well as in post-stroke aged Sprague-Dawley rats exposed to H2S- induced hypothermia. Results: Two days exposure to mild hypothermia diminishes the expression...

Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL) Reveals the Sequential Differentiation of Sieve Element-Like Cells.

Science.gov (United States)

Kondo, Yuki; Nurani, Alif Meem; Saito, Chieko; Ichihashi, Yasunori; Saito, Masato; Yamazaki, Kyoko; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Fukuda, Hiroo

2016-06-01

Cell differentiation is a complex process involving multiple steps, from initial cell fate specification to final differentiation. Procambial/cambial cells, which act as vascular stem cells, differentiate into both xylem and phloem cells during vascular development. Recent studies have identified regulatory cascades for xylem differentiation. However, the molecular mechanism underlying phloem differentiation is largely unexplored due to technical challenges. Here, we established an ectopic induction system for phloem differentiation named Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL). Our results verified similarities between VISUAL-induced Arabidopsis thaliana phloem cells and in vivo sieve elements. We performed network analysis using transcriptome data with VISUAL to dissect the processes underlying phloem differentiation, eventually identifying a factor involved in the regulation of the master transcription factor gene APL Thus, our culture system opens up new avenues not only for genetic studies of phloem differentiation, but also for future investigations of multidirectional differentiation from vascular stem cells. © 2016 American Society of Plant Biologists. All rights reserved.

Effects of gamma rays on rat vascular smooth muscle fibers

Energy Technology Data Exchange (ETDEWEB)

Ghassan, A [Radio-Biology and Health Dept. Syrian Atomic Energy Commission, (Syrian Arab Republic)

1995-10-01

Modifications of the Vasomotoricity induced by gamma rays have been investigated. Vascular smooth muscle fibres (VSMF) of rat portal vein have been used in this study. Irradiation procedures using a {sup 60} Co source have been carried out as follows: - Whole body irradiation. - Irradiation of isolated portal vein and isolated VSMF. Our results show that : 1-irradiation reduces the functional competition between Mg{sup 2+} and Ca{sup 2+}, thus hyper magnetic Krebs solutions have a negligible effect on irradiated VSMF. 2- irradiation activates Ca{sup 2+} influx into the VSMF. Thus the effect of hypocalcemic solutions on irradiated VSMF is minor compared with control. 3- Hyperpotassic solutions provoke titanic contractions with high amplitude on the irradiated VSMF compared with control. 5 figs.

Isolation, culture and intraportal transplantation of rat marrow stromal cell

International Nuclear Information System (INIS)

Wang Ping; Wang Jianhua; Yan Zhiping; Li Wentao; Lin Genlai; Hu Meiyu; Wang Yanhong

2004-01-01

Objective: To observe the tracing and evolution of marrow stromal cell (MSC) after intraportal transplantation into the liver of homogenous rats, and to provide experimental data for MSC differentiation to hepatocyte in vivo. Methods: The MSC was isolated from the leg bone marrow of adult SD rats, and purified by culture-expanded in vitro. Before transplantation, MSC was labeled with DAPI. Then 10 5 MSC were intraportally transplanted into the homogenous rat liver. Rats were killed at 2 hours and 1, 2, 3 and 4 weeks after transplantation. The cryosection samples of liver and lung were observed under fluorescence microscopy. Results: MSC in vitro culture had high ability of proliferation. Except 4 rats were dead because of abdominal bleeding or infection, other recipients were healthy until sacrificed. The implantation cells were detected by identifying the DAPI labeled MSC in the host livers, but not in the host lungs. Conclusion: Intraportal transplanted MSC could immigrate and survive in the host livers at least for 4 weeks. They could immigrate from the small branches of portal veins to hepatic parenchyma

Toxicity of aerosol propellants in the respiratory and circulatory systems. VI. Influence of cardiac and pulmonary vascular lesions in the rat.

Science.gov (United States)

Doherty, R E; Aviado, D M

1975-01-01

Three propellants were selected for investigation in rats because of their non-uniform effect in mice and monkeys. Trichlorofluoromethane (FC 11) provoked arrhythmia in all three animal species, dichlorodifluoromethane (FC 12) in monkeys and rats but not in mice, and difluoroethane (FC 152a) only in rats. In rats the alterations in heart rate and electrocardiographic pattern during inhalation of these propellants are largely brought about by release of catecholamines from the adrenal gland, because adrenalectomy or prior injection of beta-adrenergic blocking drugs decreased the incidence of cardiac effects. Rats that have pulmonary vascular thrombosis or cardiac necrosis become more sensitive to proarrhythmic activity of these propellants.

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

International Nuclear Information System (INIS)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath

2014-01-01

We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91 st day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E max of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

Energy Technology Data Exchange (ETDEWEB)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath, E-mail: snsarkar1911@rediffmail.com

2014-10-01

We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91{sup st} day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E{sub max} of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

Vascular Remodeling in Experimental Hypertension

Directory of Open Access Journals (Sweden)

Norma R. Risler

2005-01-01

Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

Arachidonic metabolism and radiation toxicity in cultures of vascular endothelial cells

International Nuclear Information System (INIS)

Eldor, A.; Vlodavsky, I.; Fuks, Z.; Matzner, Y.; Rubin, D.B.

1989-01-01

The authors conclude that the observed changes in eicosanoid production by vascular endothelial cells exposed to ionizing irradiation may be relevant to the pathogenesis of post-radiation injury in small and large blood vessels. Anomalies of PGI 2 production may lead to thrombosis and accelerated arteriosclerosis which are observed in irradiated vessels. The generation of potent cells may greatly facilitate inflammation in irradiated vessels. The model of irradiated cultured endothelial cells may also be useful for the study of various methods and agents aimed at reducing the radiation induced damage to blood vessels. Evaluation of the capacity of cultured endothelial cells to produce eicosanoids may serve as an appropriate index for the metabolic damage induced by radiation. (author)

Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

Science.gov (United States)

Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

2017-02-01

Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Culture of equine bone marrow mononuclear fraction and adipose tissue-derived stromal vascular fraction cells in different media

Directory of Open Access Journals (Sweden)

Gesiane Ribeiro

2013-12-01

Full Text Available The objective of this study was to evaluate the culture of equine bone marrow mononuclear fraction and adipose tissue - derived stromal vascular fraction cells in two different cell culture media. Five adult horses were submitted to bone marrow aspiration from the sternum, and then from the adipose tissue of the gluteal region near the base of the tail. Mononuclear fraction and stromal vascular fraction were isolated from the samples and cultivated in DMEM medium supplemented with 10% fetal bovine serum or in AIM-V medium. The cultures were observed once a week with an inverted microscope, to perform a qualitative analysis of the morphology of the cells as well as the general appearance of the cell culture. Colony-forming units (CFU were counted on days 5, 15 and 25 of cell culture. During the first week of culture, differences were observed between the samples from the same source maintained in different culture media. The number of colonies was significantly higher in samples of bone marrow in relation to samples of adipose tissue.

Static pressure accelerates ox-LDL-induced cholesterol accumulation via SREBP-1-mediated caveolin-1 downregulation in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Luo, Di-xian; Xia, Cheng-lai; Li, Jun-mu; Xiong, Yan; Yuan, Hao-yu; TANG, Zhen-Wang; Zeng, Yixin; Liao, Duan-fang

2010-01-01

Research highlights: → Vertical static pressure accelerates ox-LDL-induced cholesterol accumulation in cultured vascular smooth muscle cells. → Static pressure induces SREBP-1 activation. → Static pressure downregulates the expressions of caveolin-1 by activating SREBP-1. → Static pressure also downregulates the transcription of ABCA1 by activating SREBP-1. → Static pressure increases ox-LDL-induced cholesterol accumulation by SREBP-1-mediated caveolin-1 downregulation in vascular smooth muscle cells cultured in vitro. -- Abstract: Objective: To investigate the effect of static pressure on cholesterol accumulation in vascular smooth muscle cells (VSMCs) and its mechanism. Methods: Rat-derived VSMC cell line A10 treated with 50 mg/L ox-LDL and different static pressures (0, 60, 90, 120, 150, 180 mm Hg) in a custom-made pressure incubator for 48 h. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC; The mRNA levels of caveolin-1 and ABCA1, the protein levels of caveolin-1 SREBP-1 and mature SREBP-1 were respectively detected by RT-PCR or western blot. ALLN, an inhibitor of SREBP metabolism, was used to elevate SREBP-1 protein level in VSMCs treated with static pressure. Results: Static pressures significantly not only increase intracellular lipid droplets in VSMCs, but also elevate cellular lipid content in a pressure-dependent manner. Intracellular free cholesterol (FC), cholesterol ester (CE), total cholesterol (TC) were respectively increased from 60.5 ± 2.8 mg/g, 31.8 ± 0.7 mg/g, 92.3 ± 2.1 mg/g at atmosphere pressure (ATM, 0 mm Hg) to 150.8 ± 9.4 mg/g, 235.9 ± 3.0 mg/g, 386.7 ± 6.4 mg/g at 180 mm Hg. At the same time, static pressures decrease the mRNA and protein levels of caveolin-1, and induce the activation and nuclear translocation of SREBP-1. ALLN increases the protein level of mature SREBP-1 and decreases caveolin-1 expression, so that cellular lipid levels were upregulated. Conclusion: Static

Static pressure accelerates ox-LDL-induced cholesterol accumulation via SREBP-1-mediated caveolin-1 downregulation in cultured vascular smooth muscle cells

Energy Technology Data Exchange (ETDEWEB)

Luo, Di-xian, E-mail: luodixian_2@163.com [Department of Pharmacology, School of Pharmaceutics, Central South University, Changsha 410083, Hunan (China); Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); First People' s Hospital of Chenzhou City, Chenzhou 423000, Hunan (China); Xia, Cheng-lai [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Department of Pharmacy, Third Affiliated Hospital Medical College of Guangzhou, Guangzhou 510150, Guangdong (China); Li, Jun-mu [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Xiong, Yan [Department of Pharmacology, School of Pharmaceutics, Central South University, Changsha 410083, Hunan (China); Yuan, Hao-yu [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Lusong Center for Disease Control and Prevention, Zhuzhou 412000, Hunan (China); TANG, Zhen-Wang; Zeng, Yixin [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Liao, Duan-fang, E-mail: dfliao66@yahoo.com.cn [Institute of Pharmacy and Pharmacology, College of Science and Technology, University of South China, Hengyang 421001, Hunan (China); Department of Traditional Chinese Diagnostics, School of Pharmacy, Hunan University of Chinese Medicine, Changsha 420108, Hunan (China)

2010-12-03

Research highlights: {yields} Vertical static pressure accelerates ox-LDL-induced cholesterol accumulation in cultured vascular smooth muscle cells. {yields} Static pressure induces SREBP-1 activation. {yields} Static pressure downregulates the expressions of caveolin-1 by activating SREBP-1. {yields} Static pressure also downregulates the transcription of ABCA1 by activating SREBP-1. {yields} Static pressure increases ox-LDL-induced cholesterol accumulation by SREBP-1-mediated caveolin-1 downregulation in vascular smooth muscle cells cultured in vitro. -- Abstract: Objective: To investigate the effect of static pressure on cholesterol accumulation in vascular smooth muscle cells (VSMCs) and its mechanism. Methods: Rat-derived VSMC cell line A10 treated with 50 mg/L ox-LDL and different static pressures (0, 60, 90, 120, 150, 180 mm Hg) in a custom-made pressure incubator for 48 h. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC; The mRNA levels of caveolin-1 and ABCA1, the protein levels of caveolin-1 SREBP-1 and mature SREBP-1 were respectively detected by RT-PCR or western blot. ALLN, an inhibitor of SREBP metabolism, was used to elevate SREBP-1 protein level in VSMCs treated with static pressure. Results: Static pressures significantly not only increase intracellular lipid droplets in VSMCs, but also elevate cellular lipid content in a pressure-dependent manner. Intracellular free cholesterol (FC), cholesterol ester (CE), total cholesterol (TC) were respectively increased from 60.5 {+-} 2.8 mg/g, 31.8 {+-} 0.7 mg/g, 92.3 {+-} 2.1 mg/g at atmosphere pressure (ATM, 0 mm Hg) to 150.8 {+-} 9.4 mg/g, 235.9 {+-} 3.0 mg/g, 386.7 {+-} 6.4 mg/g at 180 mm Hg. At the same time, static pressures decrease the mRNA and protein levels of caveolin-1, and induce the activation and nuclear translocation of SREBP-1. ALLN increases the protein level of mature SREBP-1 and decreases caveolin-1 expression, so that cellular lipid levels were

(-)-Epicatechin administration and exercising skeletal muscle vascular control and microvascular oxygenation in healthy rats.

Science.gov (United States)

Copp, Steven W; Inagaki, Tadakatsu; White, Michael J; Hirai, Daniel M; Ferguson, Scott K; Holdsworth, Clark T; Sims, Gabrielle E; Poole, David C; Musch, Timothy I

2013-01-15

Consumption of the dietary flavanol (-)-epicatechin (EPI) is associated with enhanced endothelial function and augmented skeletal muscle capillarity and mitochondrial volume density. The potential for EPI to improve peripheral vascular function and muscle oxygenation during exercise is unknown. We tested the hypothesis that EPI administration in healthy rats would improve treadmill exercise performance secondary to elevated skeletal muscle blood flow and vascular conductance [VC, blood flow/mean arterial pressure (MAP)] and improved skeletal muscle microvascular oxygenation. Rats received water (control, n = 12) or 4 mg/kg EPI (n = 12) via oral gavage daily for 24 days. Exercise endurance capacity and peak O(2) uptake (Vo(2) peak) were measured via treadmill runs to exhaustion. MAP (arterial catheter) and blood flow (radiolabeled microspheres) were measured and VC was calculated during submaximal treadmill exercise (25 m/min, 5% grade). Spinotrapezius muscle microvascular O(2) pressure (Po(2mv)) was measured (phosphorescence quenching) during electrically induced twitch (1 Hz) contractions. In conscious rats, EPI administration resulted in lower (↓~5%) resting (P = 0.03) and exercising (P = 0.04) MAP. There were no differences in exercise endurance capacity, Vo(2) peak, total exercising hindlimb blood flow (control, 154 ± 13; and EPI, 159 ± 8 ml·min(-1)·100 g(-1), P = 0.68), or VC (control, 1.13 ± 0.10; and EPI, 1.24 ± 0.08 ml·min(-1)·100 g(-1)·mmHg(-1), P = 0.21) between groups. Following anesthesia, EPI resulted in lower MAP (↓~16%) but did not impact resting Po(2mv) or any kinetics parameters (P > 0.05 for all) during muscle contractions compared with control. EPI administration (4 mg·kg(-1)·day(-1)) improved modestly cardiovascular function (i.e., ↓MAP) with no impact on exercise performance, total exercising skeletal muscle blood flow and VC, or contracting muscle microvascular oxygenation in healthy rats.

Comparative sensitivity of human and rat neural cultures to chemical-induced inhibition of neurite outgrowth

Energy Technology Data Exchange (ETDEWEB)

Harrill, Joshua A.; Freudenrich, Theresa M.; Robinette, Brian L.; Mundy, William R., E-mail: mundy.william@epa.gov

2011-11-15

There is a need for rapid, efficient and cost-effective alternatives to traditional in vivo developmental neurotoxicity testing. In vitro cell culture models can recapitulate many of the key cellular processes of nervous system development, including neurite outgrowth, and may be used as screening tools to identify potential developmental neurotoxicants. The present study compared primary rat cortical cultures and human embryonic stem cell-derived neural cultures in terms of: 1) reproducibility of high content image analysis based neurite outgrowth measurements, 2) dynamic range of neurite outgrowth measurements and 3) sensitivity to chemicals which have been shown to inhibit neurite outgrowth. There was a large increase in neurite outgrowth between 2 and 24 h in both rat and human cultures. Image analysis data collected across multiple cultures demonstrated that neurite outgrowth measurements in rat cortical cultures were more reproducible and had higher dynamic range as compared to human neural cultures. Human neural cultures were more sensitive than rat cortical cultures to chemicals previously shown to inhibit neurite outgrowth. Parallel analysis of morphological (neurite count, neurite length) and cytotoxicity (neurons per field) measurements were used to detect selective effects on neurite outgrowth. All chemicals which inhibited neurite outgrowth in rat cortical cultures did so at concentrations which did not concurrently affect the number of neurons per field, indicating selective effects on neurite outgrowth. In contrast, more than half the chemicals which inhibited neurite outgrowth in human neural cultures did so at concentrations which concurrently decreased the number of neurons per field, indicating that effects on neurite outgrowth were secondary to cytotoxicity. Overall, these data demonstrate that the culture models performed differently in terms of reproducibility, dynamic range and sensitivity to neurite outgrowth inhibitors. While human neural

Comparative sensitivity of human and rat neural cultures to chemical-induced inhibition of neurite outgrowth

International Nuclear Information System (INIS)

Harrill, Joshua A.; Freudenrich, Theresa M.; Robinette, Brian L.; Mundy, William R.

2011-01-01

There is a need for rapid, efficient and cost-effective alternatives to traditional in vivo developmental neurotoxicity testing. In vitro cell culture models can recapitulate many of the key cellular processes of nervous system development, including neurite outgrowth, and may be used as screening tools to identify potential developmental neurotoxicants. The present study compared primary rat cortical cultures and human embryonic stem cell-derived neural cultures in terms of: 1) reproducibility of high content image analysis based neurite outgrowth measurements, 2) dynamic range of neurite outgrowth measurements and 3) sensitivity to chemicals which have been shown to inhibit neurite outgrowth. There was a large increase in neurite outgrowth between 2 and 24 h in both rat and human cultures. Image analysis data collected across multiple cultures demonstrated that neurite outgrowth measurements in rat cortical cultures were more reproducible and had higher dynamic range as compared to human neural cultures. Human neural cultures were more sensitive than rat cortical cultures to chemicals previously shown to inhibit neurite outgrowth. Parallel analysis of morphological (neurite count, neurite length) and cytotoxicity (neurons per field) measurements were used to detect selective effects on neurite outgrowth. All chemicals which inhibited neurite outgrowth in rat cortical cultures did so at concentrations which did not concurrently affect the number of neurons per field, indicating selective effects on neurite outgrowth. In contrast, more than half the chemicals which inhibited neurite outgrowth in human neural cultures did so at concentrations which concurrently decreased the number of neurons per field, indicating that effects on neurite outgrowth were secondary to cytotoxicity. Overall, these data demonstrate that the culture models performed differently in terms of reproducibility, dynamic range and sensitivity to neurite outgrowth inhibitors. While human neural

Sodium pump activity and calcium relaxation in vascular smooth muscle of deoxycorticosterone acetate-salt rats

International Nuclear Information System (INIS)

Soltis, E.E.; Field, F.P.

1986-01-01

The Na + -K + pump activity was determined in femoral arterial smooth muscle from deoxycorticosterone acetate (DOCA)-salt hypertensive rats using potassium relaxation and ouabain-sensitive 86 Rb uptake as indices. The membrane-stabilizing effect of calcium and its relation to Na + -K + pump activity also were examined. Femoral arteries from DOCA-salt rats exhibited a greater relaxation in response to potassium addition after contraction with norepinephrine in a low potassium (0.6 mM) Krebs solution. The concentration of potassium required to produce a 50% relaxation was significantly less in DOCA-salt rats. Ouabain-sensitive 86 Rb uptake was significantly greater at 3, 10, and 20 minutes of 86 Rb incubation in femoral arteries from DOCA-salt rats. Linear regression analysis revealed a significant correlation between the uptake of 86 Rb and time of incubation in both control and DOCA-salt rats. A significant difference in the slopes of the regression lines showed that the rate of uptake was greater in DOCA-salt rats. No difference was observed in ouabain-insensitive 86 Rb uptake. A dose-dependent relaxation in response to increasing concentrations of calcium following contraction to norepinephrine was observed in femoral arteries from control and DOCA-salt rats. The relaxation was directly dependent on the level of extracellular potassium and was blocked by ouabain. Femoral arteries from DOCA-salt rats relaxed to a significantly greater extent in response to calcium at each level of potassium when compared with controls. These results provide further evidence for an increase in Na + -K + pump activity in vascular smooth muscle from DOCA-salt hypertensive rats

Kinetics of cardiac and vascular remodeling by spontaneously hypertensive rats after discontinuation of long-term captopril treatment

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W.A. Rocha

2010-04-01

Full Text Available Angiotensin-converting enzyme inhibitors reduce blood pressure and attenuate cardiac and vascular remodeling in hypertension. However, the kinetics of remodeling after discontinuation of the long-term use of these drugs are unknown. Our objective was to investigate the temporal changes occurring in blood pressure and vascular structure of spontaneously hypertensive rats (SHR. Captopril treatment was started in the pre-hypertensive state. Rats (4 weeks were assigned to three groups: SHR-Cap (N = 51 treated with captopril (1 g/L in drinking water from the 4th to the 14th week; SHR-C (N = 48 untreated SHR; Wistar (N = 47 control rats. Subgroups of animals were studied at 2, 4, and 8 weeks after discontinuation of captopril. Direct blood pressure was recorded in freely moving animals after femoral artery catheterism. The animals were then killed to determine left ventricular hypertrophy (LVH and the aorta fixed at the same pressure measured in vivo. Captopril prevented hypertension (105 ± 3 vs 136 ± 5 mmHg, LVH (2.17 ± 0.05 vs 2.97 ± 0.14 mg/g body weight and the increase in cross-sectional area to luminal area ratio of the aorta (0.21 ± 0.01 vs 0.26 ± 0.02 μm² (SHR-Cap vs SHR-C. However, these parameters increased progressively after discontinuation of captopril (22nd week: 141 ± 2 mmHg, 2.50 ± 0.06 mg/g, 0.27 ± 0.02 μm². Prevention of the development of hypertension in SHR by using captopril during the prehypertensive period prevents the development of cardiac and vascular remodeling. Recovery of these processes follows the kinetic of hypertension development after discontinuation of captopril.

A method for isolating identifying and culturing of rat trachea-bronchia epithelial cells

International Nuclear Information System (INIS)

Cui Fengmei; Su Shibiao; Nie Jihua; Li Bingyan; Tong Jian

2005-01-01

Objective: To explore a method for isolating identifying and culturing the rat trachea-bronchia epithelial cells. Methods: The rat trachea-bronchia epithelial cells were isolated by digestion with pronase and brushing with cell brush, identified using confocul and cultured in entire F12 media with no serum. Results: With this method, cells in high purity and high viability could be obtained, and about 10 6 cells per rat. The cells grow well in entire F12 media with no serum. Conclusion: The method is useful for isolating rate trachea-bronchia epithelial cells and the entire F12 media with no serum is effective for culturing. (authors)

Impact of dietary nitrate supplementation via beetroot juice on exercising muscle vascular control in rats.

Science.gov (United States)

Ferguson, Scott K; Hirai, Daniel M; Copp, Steven W; Holdsworth, Clark T; Allen, Jason D; Jones, Andrew M; Musch, Timothy I; Poole, David C

2013-01-15

Dietary nitrate (NO(3)(-)) supplementation, via its reduction to nitrite (NO(2)(-)) and subsequent conversion to nitric oxide (NO) and other reactive nitrogen intermediates, reduces blood pressure and the O(2) cost of submaximal exercise in humans. Despite these observations, the effects of dietary NO(3)(-) supplementation on skeletal muscle vascular control during locomotory exercise remain unknown. We tested the hypotheses that dietary NO(3)(-) supplementation via beetroot juice (BR) would reduce mean arterial pressure (MAP) and increase hindlimb muscle blood flow in the exercising rat. Male Sprague-Dawley rats (3-6 months) were administered either NO(3)(-) (via beetroot juice; 1 mmol kg(-1) day(-1), BR n = 8) or untreated (control, n = 11) tap water for 5 days. MAP and hindlimb skeletal muscle blood flow and vascular conductance (radiolabelled microsphere infusions) were measured during submaximal treadmill running (20 m min(-1), 5% grade). BR resulted in significantly lower exercising MAP (control: 137 ± 3, BR: 127 ± 4 mmHg, P exercising hindlimb skeletal muscle blood flow (control: 108 ± 8, BR: 150 ± 11 ml min(-1) (100 g)(-1), P exercise predominantly in fast-twitch type II muscles, and provide a potential mechanism by which NO(3)(-) supplementation improves metabolic control.

Endogenous bile acid disposition in rat and human sandwich-cultured hepatocytes

Energy Technology Data Exchange (ETDEWEB)

Marion, Tracy L., E-mail: tracylmarion@qualyst.com [Curriculum in Toxicology, UNC School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7270 (United States); Perry, Cassandra H., E-mail: cassandraperry@qualyst.com [Qualyst, Inc., Durham, NC 27713 (United States); St Claire, Robert L., E-mail: bobstclaire@qualyst.com [Qualyst, Inc., Durham, NC 27713 (United States); Brouwer, Kim L.R., E-mail: kbrouwer@unc.edu [Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, CB 7569 Kerr Hall, Chapel Hill, NC 27599-7569 (United States)

2012-05-15

Sandwich-cultured hepatocytes (SCH) are used commonly to investigate hepatic transport protein-mediated uptake and biliary excretion of substrates. However, little is known about the disposition of endogenous bile acids (BAs) in SCH. In this study, four endogenous conjugated BAs common to rats and humans [taurocholic acid (TCA), glycocholic acid (GCA), taurochenodeoxycholic acid (TCDCA), and glycochenodeoxycholic acid (GCDCA)], as well as two BA species specific to rodents (α- and β-tauromuricholic acid; α/β TMCA), were profiled in primary rat and human SCH. Using B-CLEAR{sup ®} technology, BAs were measured in cells + bile canaliculi, cells, and medium of SCH by LC-MS/MS. Results indicated that, just as in vivo, taurine-conjugated BA species were predominant in rat SCH, while glycine-conjugated BAs were predominant in human SCH. Total intracellular BAs remained relatively constant over days in culture in rat SCH. Total BAs in control (CTL) cells + bile, cells, and medium were approximately 3.4, 2.9, and 8.3-fold greater in human than in rat. The estimated intracellular concentrations of the measured total BAs were 64.3 ± 5.9 μM in CTL rat and 183 ± 56 μM in CTL human SCH, while medium concentrations of the total BAs measured were 1.16 ± 0.21 μM in CTL rat SCH and 9.61 ± 6.36 μM in CTL human SCH. Treatment of cells for 24 h with 10 μM troglitazone (TRO), an inhibitor of the bile salt export pump (BSEP) and the Na{sup +}-taurocholate cotransporting polypeptide (NTCP), had no significant effect on endogenous BAs measured at the end of the 24-h culture period, potentially due to compensatory mechanisms that maintain BA homeostasis. These data demonstrate that BAs in SCH are similar to in vivo, and that SCH may be a useful in vitro model to study alterations in BA disposition if species differences are taken into account. -- Highlights: ► Bile acids (BAs) were measured in rat and human sandwich-cultured hepatocytes (SCH). ► Cell and medium BA

Endogenous bile acid disposition in rat and human sandwich-cultured hepatocytes

International Nuclear Information System (INIS)

Marion, Tracy L.; Perry, Cassandra H.; St Claire, Robert L.; Brouwer, Kim L.R.

2012-01-01

Sandwich-cultured hepatocytes (SCH) are used commonly to investigate hepatic transport protein-mediated uptake and biliary excretion of substrates. However, little is known about the disposition of endogenous bile acids (BAs) in SCH. In this study, four endogenous conjugated BAs common to rats and humans [taurocholic acid (TCA), glycocholic acid (GCA), taurochenodeoxycholic acid (TCDCA), and glycochenodeoxycholic acid (GCDCA)], as well as two BA species specific to rodents (α- and β-tauromuricholic acid; α/β TMCA), were profiled in primary rat and human SCH. Using B-CLEAR ® technology, BAs were measured in cells + bile canaliculi, cells, and medium of SCH by LC-MS/MS. Results indicated that, just as in vivo, taurine-conjugated BA species were predominant in rat SCH, while glycine-conjugated BAs were predominant in human SCH. Total intracellular BAs remained relatively constant over days in culture in rat SCH. Total BAs in control (CTL) cells + bile, cells, and medium were approximately 3.4, 2.9, and 8.3-fold greater in human than in rat. The estimated intracellular concentrations of the measured total BAs were 64.3 ± 5.9 μM in CTL rat and 183 ± 56 μM in CTL human SCH, while medium concentrations of the total BAs measured were 1.16 ± 0.21 μM in CTL rat SCH and 9.61 ± 6.36 μM in CTL human SCH. Treatment of cells for 24 h with 10 μM troglitazone (TRO), an inhibitor of the bile salt export pump (BSEP) and the Na + -taurocholate cotransporting polypeptide (NTCP), had no significant effect on endogenous BAs measured at the end of the 24-h culture period, potentially due to compensatory mechanisms that maintain BA homeostasis. These data demonstrate that BAs in SCH are similar to in vivo, and that SCH may be a useful in vitro model to study alterations in BA disposition if species differences are taken into account. -- Highlights: ► Bile acids (BAs) were measured in rat and human sandwich-cultured hepatocytes (SCH). ► Cell and medium BA concentrations

Powerful vascular protection by combining cilnidipine with valsartan in stroke-prone, spontaneously hypertensive rats

OpenAIRE

Takai, Shinji; Jin, Denan; Aritomi, Shizuka; Niinuma, Kazumi; Miyazaki, Mizuo

2012-01-01

Cilnidipine is an L- and N-type calcium channel blocker (CCB), and amlodipine is an L-type CCB. Valsartan (10?mg?kg?1), valsartan (10?mg?kg?1) and amlodipine (1?mg kg?1), and valsartan (10?mg?kg?1) and cilnidipine (1?mg?kg?1) were administered once daily for 2 weeks to stroke-prone, spontaneously hypertensive rats (SHR-SPs). Blood pressure was significantly reduced by valsartan, and it was further reduced by the combination therapies. Vascular endothelial dysfunction was significantly attenua...

Characterization of dynamic changes in vascular reactivity following treatment with carmustine in Sprague-Dawley rats

International Nuclear Information System (INIS)

Rawson, C.L.

1985-01-01

Carmustine, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), is a highly effective anti-cancer drug and bone marrow suppressant agent in humans and animals. Pilot studies demonstrated that BCNU induced a time- and dose-dependent supersensitivity to norepinephrine (NE) in rat caudal arteries after a single dose. The studies presented in this thesis were performed to determine the mechanism for this supersensitivity. Male Sprague-Dawley rats were administered a single dose of BCNU (25 mg/kg, i.p.) on day 0. On day 7 a proximal section of caudal artery was doubly cannulated and perfused intraluminally with Krebs bicarbonate physiological buffer. These studies demonstrated that the supersensitivity induced by BCNU treatment was pre-junctional. Denervation of caudal arteries with 6-hydroxydopamine led to a significant decrease in the EC 50 for NE in caudal arteries from control rats but not BCNU treated rats. The EC 50 for NE in control-denervated arterial segments was not statistically different from BCNU-denervated or BCNU-nondenervated segments. Metabolism of [ 3 H] NE to its 5 primary metabolites, as determined by thin layer chromatography, and uptake of [ 3 H] NE were significantly lower in caudal arteries taken from BCNU treated rats. These data demonstrate that a pre-junctional mechanism was responsible for vascular supersensitivity to NE after BCNU treatment in caudal arteries from Sprague-Dawley rats

Dose-response analysis of phthalate effects on gene expression in rat whole embryo culture

NARCIS (Netherlands)

Robinson, J.F.; Verhoef, A.; van Beelen, V.A.; Pennings, J.L.A.; Piersma, A.H.|info:eu-repo/dai/nl/071276947

2012-01-01

The rat postimplantation whole embryo culture (WEC) model serves as a potential screening tool for developmental toxicity. In this model, cultured rat embryos are exposed during early embryogenesis and evaluated for morphological effects. The integration of molecular-based markers may lead to

Neuroprotection, learning and memory improvement of a standardized extract from Renshen Shouwu against neuronal injury and vascular dementia in rats with brain ischemia.

Science.gov (United States)

Wan, Li; Cheng, Yufang; Luo, Zhanyuan; Guo, Haibiao; Zhao, Wenjing; Gu, Quanlin; Yang, Xu; Xu, Jiangping; Bei, Weijian; Guo, Jiao

2015-05-13

The Renshen Shouwu capsule (RSSW) is a patented Traditional Chinese Medicine (TCM), that has been proven to improve memory and is widely used in China to apoplexy syndrome and memory deficits. To investigate the neuroprotective and therapeutic effect of the Renshen Shouwu standardized extract (RSSW) on ischemic brain neuronal injury and impairment of learning and memory related to Vascular Dementia (VD) induced by a focal and global cerebral ischemia-reperfusion injury in rats. Using in vivo rat models of both focal ischemia/reperfusion (I/R) injuries induced by a middle cerebral artery occlusion (MCAO), and VD with transient global brain I/R neuronal injuries induced by a four-vessel occlusion (4-VO) in Sprague-Dawley (SD) rats, RSSW (50,100, and 200 mg kg(-1) body weights) and Egb761® (80 mg kg(-1)) were administered orally for 20 days (preventively 6 days+therapeutically 14 days) in 4-VO rats, and for 7 days (3 days preventively+4 days therapeutically) in MCAO rats. Learning and memory behavioral performance was assayed using a Morris water maze test including a place navigation trial and a spatial probe trial. Brain histochemical morphology and hippocampal neuron survival was quantified using microscope assay of a puffin brain/hippocampus slice with cresyl violet staining. MCAO ischemia/reperfusion caused infarct damage in rat brain tissue. 4-VO ischemia/reperfusion caused a hippocampal neuronal lesion and learning and memory deficits in rats. Administration of RSSW (50, 100, and 200mg/kg) or EGb761 significantly reduced the size of the insulted brain hemisphere lesion and improved the neurological behavior of MCAO rats. In addition, RSSW markedly reduced an increase in the brain infarct volume from an I/R-induced MCAO and reduced the cerebral water content in a dose-dependent way. Administration of RSSW also increased the pyramidal neuronal density in the hippocampus of surviving rats after transient global brain ischemia and improved the learning and memory

Effects of ouabain on vascular reactivity

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Vassallo D.V.

1997-04-01

Full Text Available Ouabain is an endogenous substance occurring in the plasma in the nanomolar range, that has been proposed to increase vascular resistance and induce hypertension. This substance acts on the a-subunit of Na+,K+-ATPase inhibiting the Na+-pump activity. In the vascular smooth muscle this effect leads to intracellular Na+ accumulation that reduces the activity of the Na+/Ca2+ exchanger and to an increased vascular tone. It was also suggested that circulating ouabain, even in the nanomolar range, sensitizes the vascular smooth muscle to vasopressor substances. We tested the latter hypothesis by studying the effects of ouabain in the micromolar and nanomolar range on phenylephrine (PE-evoked pressor responses. The experiments were performed in normotensive and hypertensive rats in vivo, under anesthesia, and in perfused rat tail vascular beds. The results showed that ouabain pretreatment increased the vasopressor responses to PE in vitro and in vivo. This sensitization after ouabain treatment was also observed in hypertensive animals which presented an enhanced vasopressor response to PE in comparison to normotensive animals. It is suggested that ouabain at nanomolar concentrations can sensitize vascular smooth muscle to vasopressor stimuli possibly contributing to increased tone in hypertension

S1P1 receptor modulation preserves vascular function in mesenteric and coronary arteries after CPB in the rat independent of depletion of lymphocytes.

Directory of Open Access Journals (Sweden)

Iryna V Samarska

Full Text Available BACKGROUND: Cardiopulmonary bypass (CPB may induce systemic inflammation and vascular dysfunction. Sphingosine 1-phosphate (S1P modulates various vascular and immune responses. Here we explored whether agonists of the S1P receptors, FTY720 and SEW2871 improve vascular reactivity after CPB in the rat. METHODS: Experiments were done in male Wistar rats (total n = 127. Anesthesia was induced by isoflurane (2.5-3% and maintained by fentanyl and midazolam during CPB. After catheterization of the left femoral artery, carotid artery and the right atrium, normothermic extracorporeal circulation was instituted for 60 minutes. In the first part of the study animals were euthanized after either 1 hour, 1 day, 2 or 5 days of the recovery period. In second part of the study animals were euthanized after 1 day of postoperative period. We evaluated the contractile response to phenylephrine (mesenteric arteries or to serotonin (coronary artery and vasodilatory response to acethylcholine (both arteries. RESULTS: Contractile responses to phenylephrine were reduced at 1 day recovery after CPB and Sham as compared to healthy control animals (Emax, mN: 7.9 ± 1.9, 6.5 ± 1.5, and 11.3 ± 1.3, respectively. Mainly FTY720, but not SEW2871, caused lymphopenia in both Sham and CPB groups. In coronary and mesenteric arteries, both FTY720 and SEW2871 normalized serotonin and phenylephrine-mediated vascular reactivity after CPB (p<0.05 and FTY720 increased relaxation to acetylcholine as compared with untreated rats that underwent CPB. CONCLUSION: Pretreatment with FTY720 or SEW2871 preserves vascular function in mesenteric and coronary artery after CPB. Therefore, pharmacological activation of S1P1 receptors may provide a promising therapeutic intervention to prevent CPB-related vascular dysfunction in patients.

Role of Nitric Oxide Synthase on Blood Pressure Regulation and Vascular Function in Pregnant Rats on a High-Fat Diet.

Science.gov (United States)

Palei, Ana C; Spradley, Frank T; Granger, Joey P

2017-03-01

While obesity is a leading risk factor for preeclampsia, the mechanisms whereby obese women are more susceptible to pregnancy-induced hypertension are unclear. As high-fat diet (HFD) is an important contributor to the development of obesity, we tested the hypothesis that pregnant rats on HFD have hypertension and endothelial dysfunction due to reduced nitric oxide synthase (NOS). Twelve-week-old Sprague-Dawley female rats were fed normal diet (ND, 13% fat kcal) or HFD (40% fat kcal) for 9 weeks. Timed-pregnant rats were then generated and the effect of HFD on mean arterial blood pressure (MAP) and vascular function was assessed on gestational day (GD) 19. MAP was not different between HFD and ND pregnant rats. Intriguingly, sensitivity to acetylcholine-induced endothelium-dependent vasorelaxation was enhanced in small mesenteric arteries of HFD dams compared to ND controls (logEC50 -7.9 ± 0.3 vs. -6.7 ± 0.3 M; P hydrochloride (100 mg/l, drinking water) from GD 14 to 19. It was found that NOS inhibition increased MAP equally in HFD and ND groups. Contrary to our initial hypothesis, HFD dams were normotensive and presented increased endothelial function and NO/NOS3 levels. This enhanced NOS-mediated vascular function does not appear to have a major impact on blood pressure regulation of HFD-fed pregnant rats. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Rat brain sagittal organotypic slice cultures as an ex vivo dopamine cell loss system.

Science.gov (United States)

McCaughey-Chapman, Amy; Connor, Bronwen

2017-02-01

Organotypic brain slice cultures are a useful tool to study neurological function as they provide a more complex, 3-dimensional system than standard 2-dimensional in vitro cell cultures. Building on a previously developed mouse brain slice culture protocol, we have developed a rat sagittal brain slice culture system as an ex vivo model of dopamine cell loss. We show that rat brain organotypic slice cultures remain viable for up to 6 weeks in culture. Using Fluoro-Gold axonal tracing, we demonstrate that the slice 3-dimensional cytoarchitecture is maintained over a 4 week culturing period, with particular focus on the nigrostriatal pathway. Treatment of the cultures with 6-hydroxydopamine and desipramine induces a progressive loss of Fluoro-Gold-positive nigral cells with a sustained loss of tyrosine hydroxylase-positive nigral cells. This recapitulates the pattern of dopaminergic degeneration observed in the rat partial 6-hydroxydopamine lesion model and, most importantly, the progressive pathology of Parkinson's disease. Our slice culture platform provides an advance over other systems, as we demonstrate for the first time 3-dimensional cytoarchitecture maintenance of rat nigrostriatal sagittal slices for up to 6 weeks. Our ex vivo organotypic slice culture system provides a long term cellular platform to model Parkinson's disease, allowing for the elucidation of mechanisms involved in dopaminergic neuron degeneration and the capability to study cellular integration and plasticity ex vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

Generation of a vascularized organoid using skeletal muscle as the inductive source.

LENUS (Irish Health Repository)

Messina, Aurora

2005-09-01

The technology required for creating an in vivo microenvironment and a neovasculature that can grow with and service new tissue is lacking, precluding the possibility of engineering complex three-dimensional organs. We have shown that when an arterio-venous (AV) loop is constructed in vivo in the rat groin, and placed inside a semisealed chamber, an extensive functional vasculature is generated. To test whether this unusually angiogenic environment supports the survival and growth of implanted tissue or cells, we inserted various preparations of rat and human skeletal muscle. We show that after 6 weeks incubation of muscle tissue, the chamber filled with predominantly well-vascularized recipient-derived adipose tissue, but some new donor-derived skeletal muscle and connective tissue were also evident. When primary cultured myoblasts were inserted into the chamber with the AV loop, they converted to mature striated muscle fibers. Furthermore, we identify novel adipogenesis-inducing properties of skeletal muscle. This represents the first report of a specific three-dimensional tissue grown on its own vascular supply.

[Experiment study on ultrashort wave for treating vascular crisis after rat tail replantation].

Science.gov (United States)

Tan, Long; Gao, Wenshan; Xi, Ali; Wang, Cong; Chen, Shouying; Zhao, Yanyan; Di, Keqian; Yang, Xincai; Weng, Shengbin

2012-10-01

To explore the effect and mechanism of ultrashort wave (USW) for prevention and treatment of vascular crisis after rat tail replantation. Eighty 3-month old female Sprague Dawley rats (weighing 232.8-289.6 g) were randomly divided into 5 groups. In each group, based on the caudal vein and the coccyx was retained, the tail was cut off. The tail artery was ligated in group A; the tail artery was anastomosed in groups B, C, D, and E to establish the tail replantation model. After surgery, the rats of group B were given normal management; the rats of group C were immediately given intraperitoneal injection (3.125 mL/kg) of diluted papaverine hydrochloride injection (1 mg/mL); the rats of groups D and E were immediately given the local USW treatment (once a day) at anastomotic site for 5 days at the dosage of 3 files and 50 mA for 20 minutes (group D) and 2 files and 28 mA for 20 minutes (group E). The survival rate of the rat tails was observed for 10 days after the tail replantation. The tail skin temperature difference between proximal and distal anastomosis was measured at pre- and post-operation; the change between postoperative and preoperative temperature difference was calculated. The blood plasma specimens were collected from the inner canthus before operation and from the tip of the tail at 8 hours after operation to measure the content of nitric oxide (NO). The survival rates of the rat tails were 0 (0/14), 36.4% (8/22), 57.1% (8/14), 22.2% (4/18), and 75.0% (9/12) in groups A, B, C, D, and E, respectively, showing significant overall differences among 5 groups (chi2 = 19.935, P = 0.001); the survival rate of group E was significantly higher than that of group B at 7 days (P 0.05). At preoperation, there was no significant difference in tail skin temperature difference among 5 groups (P > 0.05); at 8 hours, 5 days, 6 days, and 7 days after operation, significant overall difference was found in the change of the skin temperature difference among groups (P

Upregulation of endothelin ETB receptor-mediated vasoconstriction in rat coronary artery after organ culture

DEFF Research Database (Denmark)

Eskesen, Karen; Edvinsson, Lars

2006-01-01

The aim of this study was to examine if endothelin ET(B) receptor-mediated contraction occurred in isolated segments of rat coronary arteries during organ culture. Presence of contractile endothelin ET(B) receptors was studied by measuring the change in isometric tension in rings of left anterior......(+)-solution was not modified after 1 day in culture medium. The experiments indicate that organ culture of rat coronary arteries upregulate endothelin ET(B) receptor-mediated contraction by inducing synthesis of new protein....... descending coronary arteries isolated from hearts of rats as response to application of the selective endothelin ET(B) receptor agonist, Sarafotoxin 6c and endothelin-1. In segments cultured 1 day in serum free Dulbecco's Modified Eagle's Medium, Sarafotoxin 6c induced a concentration dependent contraction...

The rat whole embryo culture assay using the Dysmorphology Score system.

Science.gov (United States)

Zhang, Cindy; Panzica-Kelly, Julie; Augustine-Rauch, Karen

2013-01-01

The rat whole embryo culture (WEC) system has been used extensively for characterizing teratogenic properties of test chemicals. In this chapter, we describe the methodology for culturing rat embryos as well as a new morphological score system, the Dysmorphology Score (DMS) system for assessing morphology of mid gestation (gestational day 11) rat embryos. In contrast to the developmental stage focused scoring associated with the Brown and Fabro score system, this new score system assesses the respective degree of severity of dysmorphology, which delineates normal from abnormal morphology of specific embryonic structures and organ systems. This score system generates an approach that allows rapid identification and quantification of adverse developmental findings, making it conducive for characterization of compounds for teratogenic properties and screening activities.

Experimental study on effect of dexamethasone to the in-stent restenosis after vascular intervention

International Nuclear Information System (INIS)

Wang Jianbo; Yang Jianyong; Chen Wei; Zhuang Wenquan; Li Jiaping; Zhang Longjuan

2007-01-01

Objective: To evaluate the effect of dexamethasone to the cultured rat thoracic aortic smooth muscle cells (SMC) in vitro, and explore the role on it's prevention and cure for the in-stent restenosis after vascular intervention. Methods: The rat thoracic aortic SMC were harvested and cultured for six to ten passages. The cultured SMC were synchronized and then restimutated to enter the cell cycle, and treated with incremental concentrations of dexamethasone or without dexamethasone as control. The proliferative assay was performed with MTT method in the different time points after treatment. RT-PCR was performed to assay the level of proliferating cell nuclear antigen (PCNA) mRNA. Results: 1. Dexamethasone progressively inhibited rat aortic SMC proliferation in a concentration-dependent fashion. The A value was statistically significant for different concentrations (F=36.02, P -6 and 10 -5 mol/L (P=0.065) or between 10 -11 mol/L and control group (P 0.567). 2. RT-PCR suggested dexamethasone significantly decreased rat aortic SMC PCNA mRNA transcription in a concentration-dependent fashion. Statistical analysis indicated F=15.407 and P -9 or 10 -11 mol/L groups by post hoc analysis. Conclusions: Dexamethasone inhibits rat aortic SMC proliferation in a concentration- dependent fashion. The data suggest that effective action concentration is 10 -7 mol/L with persistent time up to 96 hours or more. Dexamethasone may play the inhibit role to SMC at lower concentration with prolonging action time. (authors)

A comparative study of myosin and its subunits in adult and neonatal-rat hearts and in rat heart cells from young and old cultures.

OpenAIRE

Ghanbari, H A; McCarl, R L

1980-01-01

A possible explanation for the decrease in myosin Ca2+-dependent ATPase activity as rat heart cells age in culture is presented. The subunit structure and enzyme kinetics of myosin from adult and neonatal rat hearts and from rat heart cells of young and old cultures are compared. These studies indicate that the loss in Ca-ATPase activity of myosin from older cultures was an intrinsic property of the myosin itself. Myofibrillar fractions from the indicated four sources showed no qualitative or...

Beneficial effects of calcitriol on hypertension, glucose intolerance, impairment of endothelium-dependent vascular relaxation, and visceral adiposity in fructose-fed hypertensive rats.

Science.gov (United States)

Chou, Chu-Lin; Pang, Cheng-Yoong; Lee, Tony J F; Fang, Te-Chao

2015-01-01

Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group). Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose) for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L). These results suggest a protective role of calcitriol treatment on endothelial function, glucose

Beneficial effects of calcitriol on hypertension, glucose intolerance, impairment of endothelium-dependent vascular relaxation, and visceral adiposity in fructose-fed hypertensive rats.

Directory of Open Access Journals (Sweden)

Chu-Lin Chou

Full Text Available Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group. Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L. These results suggest a protective role of calcitriol treatment on endothelial

Implication of Free Fatty Acids in Thrombin Generation and Fibrinolysis in Vascular Inflammation in Zucker Rats and Evolution with Aging

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Jérémy Lagrange

2017-11-01

Full Text Available Background: The metabolic syndrome (MetS and aging are associated with modifications in blood coagulation factors, vascular inflammation, and increased risk of thrombosis.Objectives: Our aim was to determine concomitant changes in thrombin generation in the blood compartment and at the surface of vascular smooth muscle cells (VSMCs and its interplay with adipokines, free fatty acids (FFA, and metalloproteinases (MMPs in obese Zucker rats that share features of the human MetS.Methods: Obese and age-matched lean Zucker rats were compared at 25 and 80 weeks of age. Thrombin generation was assessed by calibrated automated thrombography (CAT.Results: Endogenous thrombin potential (ETP was increased in obese rats independent of platelets and age. Clot half-lysis time was delayed with obesity and age. Interleukin (IL-1β and IL-13 were increased with obesity and age respectively. Addition of exogenous fibrinogen, leptin, linoleic, or palmitic acid increased thrombin generation in plasma whereas adiponectin had an opposite effect. ETP was increased at the surface of VSMCs from obese rats and addition of exogenous palmitic acid further enhanced ETP values. Gelatinase activity was increased in aorta at both ages in obese rats and MMP-2 activity was increased in VSMCs from obese rats.Conclusions: Our study demonstrated in MetS an early prothrombotic phenotype of the blood compartment reinforced by procoagulant properties of dedifferentiated and inflammatory VSMCs. Mechanisms involved (1 increased fibrinogen and impaired fibrinolysis and (2 increased saturated fatty acids responsible for additive procoagulant effects. Whether specifically targeting this hypercoagulability using direct thrombin inhibitors would improve outcome in MetS is worth investigating.

Myosin light chain kinase is necessary for post-shock mesenteric lymph drainage enhancement of vascular reactivity and calcium sensitivity in hemorrhagic-shocked rats

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Zhang, Y.P.; Niu, C.Y.; Zhao, Z.G.; Zhang, L.M.; Si, Y.H. [Institute of Microcirculation, Hebei North University, Hebei (China)

2013-08-10

Vascular hyporeactivity is an important factor in irreversible shock, and post-shock mesenteric lymph (PSML) blockade improves vascular reactivity after hemorrhagic shock. This study explored the possible involvement of myosin light chain kinase (MLCK) in PSML-mediated vascular hyporeactivity and calcium desensitization. Rats were divided into sham (n=12), shock (n=18), and shock+drainage (n=18) groups. A hemorrhagic shock model (40±2 mmHg, 3 h) was established in the shock and shock+drainage groups. PSML drainage was performed from 1 to 3 h from start of hypotension in shock+drainage rats. Levels of phospho-MLCK (p-MLCK) were determined in superior mesenteric artery (SMA) tissue, and the vascular reactivity to norepinephrine (NE) and sensitivity to Ca{sup 2+} were observed in SMA rings in an isolated organ perfusion system. p-MLCK was significantly decreased in the shock group compared with the sham group, but increased in the shock+drainage group compared with the shock group. Substance P (1 nM), an agonist of MLCK, significantly elevated the decreased contractile response of SMA rings to both NE and Ca{sup 2+} at various concentrations. Maximum contractility (E{sub max}) in the shock group increased with NE (from 0.179±0.038 to 0.440±0.177 g/mg, P<0.05) and Ca{sup 2+} (from 0.515±0.043 to 0.646±0.096 g/mg, P<0.05). ML-7 (0.1 nM), an inhibitor of MLCK, reduced the increased vascular response to NE and Ca{sup 2+} at various concentrations in the shock+drainage group (from 0.744±0.187 to 0.570±0.143 g/mg in E{sub max} for NE and from 0.729±0.037 to 0.645±0.056 g/mg in E{sub max} for Ca{sup 2+}, P<0.05). We conclude that MLCK is an important contributor to PSML drainage, enhancing vascular reactivity and calcium sensitivity in rats with hemorrhagic shock.

Growth hormone and IGF-1 deficiency exacerbate high-fat diet-induced endothelial impairment in obese Lewis dwarf rats: implications for vascular aging.

Science.gov (United States)

Bailey-Downs, Lora C; Sosnowska, Danuta; Toth, Peter; Mitschelen, Matthew; Gautam, Tripti; Henthorn, Jim C; Ballabh, Praveen; Koller, Akos; Farley, Julie A; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

2012-06-01

Previous studies suggest that the age-related decline in circulating growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels significantly contribute to vascular dysfunction in aging by impairing cellular oxidative stress resistance pathways. Obesity in elderly individuals is increasing at alarming rates, and there is evidence suggesting that elderly individuals are more vulnerable to the deleterious cardiovascular effects of obesity than younger individuals. However, the specific mechanisms through which aging, GH/IGF-1 deficiency, and obesity interact to promote the development of cardiovascular disease remain unclear. To test the hypothesis that low circulating GH/IGF-1 levels exacerbate the pro-oxidant and proinflammatory vascular effects of obesity, GH/IGF-1-deficient Lewis dwarf rats and heterozygous control rats were fed either a standard diet or a high-fat diet (HFD) for 7 months. Feeding an HFD resulted in similar relative weight gains and increases in body fat content in Lewis dwarf rats and control rats. HFD-fed Lewis dwarf rats exhibited a relative increase in blood glucose levels, lower insulin, and impaired glucose tolerance as compared with HFD-fed control rats. Analysis of serum cytokine expression signatures indicated that chronic GH/IGF-1 deficiency exacerbates HFD-induced inflammation. GH/IGF-1 deficiency also exacerbated HFD-induced endothelial dysfunction, oxidative stress, and expression of inflammatory markers (tumor necrosis factor-α, ICAM-1) in aortas of Lewis dwarf rats. Overall, our results are consistent with the available clinical and experimental evidence suggesting that GH/IGF-1 deficiency renders the cardiovascular system more vulnerable to the deleterious effects of obesity.

Prevention of vascular dysfunction and arterial hypertension in mice generated by assisted reproductive technologies by addition of melatonin to culture media.

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Rexhaj, Emrush; Pireva, Agim; Paoloni-Giacobino, Ariane; Allemann, Yves; Cerny, David; Dessen, Pierre; Sartori, Claudio; Scherrer, Urs; Rimoldi, Stefano F

2015-10-01

Assisted reproductive technologies (ART) induce vascular dysfunction in humans and mice. In mice, ART-induced vascular dysfunction is related to epigenetic alteration of the endothelial nitric oxide synthase (eNOS) gene, resulting in decreased vascular eNOS expression and nitrite/nitrate synthesis. Melatonin is involved in epigenetic regulation, and its administration to sterile women improves the success rate of ART. We hypothesized that addition of melatonin to culture media may prevent ART-induced epigenetic and cardiovascular alterations in mice. We, therefore, assessed mesenteric-artery responses to acetylcholine and arterial blood pressure, together with DNA methylation of the eNOS gene promoter in vascular tissue and nitric oxide plasma concentration in 12-wk-old ART mice generated with and without addition of melatonin to culture media and in control mice. As expected, acetylcholine-induced mesenteric-artery dilation was impaired (P = 0.008 vs. control) and mean arterial blood pressure increased (109.5 ± 3.8 vs. 104.0 ± 4.7 mmHg, P = 0.002, ART vs. control) in ART compared with control mice. These alterations were associated with altered DNA methylation of the eNOS gene promoter (P culture media prevented eNOS dysmethylation (P = 0.005, vs. ART + vehicle), normalized nitric oxide plasma concentration (23.1 ± 14.6 μM, P = 0.002 vs. ART + vehicle) and mesentery-artery responsiveness to acetylcholine (P culture media prevents ART-induced vascular dysfunction. We speculate that this approach will also allow preventing ART-induced premature atherosclerosis in humans. Copyright © 2015 the American Physiological Society.

Regulation of cyclooxygenase expression in cultured vascular cells

International Nuclear Information System (INIS)

Pash, J.M.

1988-01-01

Arachidonic acid metabolism in vascular tissue results in synthesis of prostacylin. The key enzyme in this synthesis pathway, cyclooxygenase, is down-regulated through self-inactivation. An analogous refractory state is produced by aspirin which irreversibly acetylates the enzyme. To further understand this phenomenon, the inactivation and recovery of cyclooxygenase activity was assayed in cultured ray vascular smooth muscle cells using exogenously added arachidonic acid. Self-inactivation of cyclooxygenase was observed following treatment with micromolar amounts of arachidonic acid. The recovery of cyclooxygenase activity following self-inactivation was analogous to that observed following aspirin-inactivation in that it depended on protein synthesis and required either serum or EGF. Two additional factors, TGF-β and uric acid, were found to enhance the stimulation of cyclooxygenase recovery by EGF. A defined medium containing 10 ng/mL EGF, 1 ng/mL TGFβ and 0.1 mM uric acid duplicated the cyclooxygenase recovery activity of 10% serum. Stimulation of cyclooxygenase activity by EGF and TGF-β was inhibited by cycloheximide but not by actinomycin-D, indicating a link to increased translation of pre-existing mRNA. A lack of significant effect on overall protein synthesis by EGF and TGF-β, measured by [ 35 S]-methionine incorporation under conditions where a multi-fold increase in cyclooxygenase activity was seen, indicates that the translational regulation of a small fraction of total mRNA and possibly cyclooxygenase is occurring

The effects of biomimetically conjugated VEGF on osteogenesis and angiogenesis of MSCs (human and rat) and HUVECs co-culture models.

Science.gov (United States)

Lü, Lanxin; Deegan, Anthony; Musa, Faiza; Xu, Tie; Yang, Ying

2018-07-01

The purpose of this work was to investigate if the biomimetically conjugated VEGF and HUVECs co-culture could modulate the osteogenic and angiogenic differentiation of MSCs derived from rat and human bone marrow (rMSCs and hMSCs). After treated by ammonia plasma, Poly(lactic-co-glycolic acid) (PLGA) electrospun nanofibers were immobilized with VEGF through heparin to fulfil the sustained release. The proliferation capacity of rMSCs and hMSCs on neat PLGA nanofibers (NF) and VEGF immobilized NF (NF-VEGF) surfaces were assessed by CCK-8 and compared when MSCs were mono-cultured and co-cultured with HUVECs. The effect of VEGF and HUVECs co-culturing on osteogenic and angiogenic differentiation of rMSCs and hMSCs were investigated by calcium deposits and CD31 expression on NF and NF-VEGF surfaces. The results indicated that VEGF has been biomimetically immobilized onto PLGA nanofibers surface and kept sustained release successfully. The CD31 staining results showed that both VEGF and HUVECs co-culture could enhance the angiogenesis of rMSCs and hMSCs. However, the proliferation and osteogenic differentiation of MSCs when cultured with VEGF and HUVECs showed a species dependent response. Taken together, VEGF immobilization and co-culture with HUVECs promoted angiogenesis of MSCs, indicating a good strategy for vascularization in bone tissue engineering. Copyright © 2018. Published by Elsevier B.V.

Simultaneous characterization of metabolic, cardiac, vascular and renal phenotypes of lean and obese SHHF rats.

Science.gov (United States)

Youcef, Gina; Olivier, Arnaud; L'Huillier, Clément P J; Labat, Carlos; Fay, Renaud; Tabcheh, Lina; Toupance, Simon; Rodriguez-Guéant, Rosa-Maria; Bergerot, Damien; Jaisser, Frédéric; Lacolley, Patrick; Zannad, Faiez; Laurent Vallar; Pizard, Anne

2014-01-01

Individuals with metabolic syndrome (MetS) are prone to develop heart failure (HF). However, the deleterious effects of MetS on the continuum of events leading to cardiac remodeling and subsequently to HF are not fully understood. This study characterized simultaneously MetS and cardiac, vascular and renal phenotypes in aging Spontaneously Hypertensive Heart Failure lean (SHHF(+/?) regrouping (+/+) and (+/cp) rats) and obese (SHHF(cp/cp), "cp" defective mutant allele of the leptin receptor gene) rats. We aimed to refine the milestones and their onset during the progression from MetS to HF in this experimental model. We found that SHHF(cp/cp )but not SHHF(+/?) rats developed dyslipidemia, as early as 1.5 months of age. This early alteration in the lipidic profile was detectable concomitantly to impaired renal function (polyuria, proteinuria but no glycosuria) and reduced carotid distensibility as compared to SHHF(+/?) rats. By 3 months of age SHHFcp/cp animals developed severe obesity associated with dislipidemia and hypertension defining the onset of MetS. From 6 months of age, SHHF(+/?) rats developed concentric left ventricular hypertrophy (LVH) while SHHF(cp/cp) rats developed eccentric LVH apparent from progressive dilation of the LV dimensions. By 14 months of age only SHHF(cp/cp) rats showed significantly higher central systolic blood pressure and a reduced ejection fraction resulting in systolic dysfunction as compared to SHHF(+/?). In summary, the metabolic and hemodynamic mechanisms participating in the faster decline of cardiac functions in SHHF(cp/cp) rats are established long before their physiological consequences are detectable. Our results suggest that the molecular mechanisms triggered within the first three months after birth of SHHF(cp/cp) rats should be targeted preferentially by therapeutic interventions in order to mitigate the later HF development.

Effect of gamma rays on electrically evoked contractions of non-vascular smooth muscles (rat vas deferens)

International Nuclear Information System (INIS)

Azroony, R.; Ksies, F.; Alya, G.

2002-10-01

We have tried, in this experiment, to study the modifications of non-vascular smooth muscles contraction induced via gamma rays. Smooth muscular fibers were isolated from the vas deferens of an adult rat and contractions were electrically evoked. Our results show that irradiation activates the VOC (Voltage Operated Channel) type of ionic channels which causes an increasing in the inward flux of Ca 2+ and then causes an increasing in the inner calcium concentration [Ca 2] i, the matter which means an increasing in the force of muscular contraction. Concerning to the response of vas deferens smooth muscles to the activation of membrane receptors, we have tried to study the effects of gamma rays on activating adrenergic and cholinergic receptors, also, we have tried to show the effects of different doses of gamma rays (1, 3, 5, 7 Gy) on regulating the contractile response of this type of smooth muscles. And results show that: - Irradiation increases contraction force, mediated by adrenergic and cholinergic receptors, in a dose dependent manner, with E m ax 1 Gy m axc 3 Gy m ax 5 Gy m ax 7 Gy. There is an important shift on irradiated rats (3, 5, 7 Gy) where the maximum effect of Acetylcholine (E m ax) can be obtained in lower concentrations of Acetylcholine. These results mean that irradiation activates the inward flux of Ca 2+ through the ROC (Receptors Operated Channels) type of ionic channels, which rely, in their activation, on activating the membrane receptors. By comparing these results with the effects of gamma rays on activating vascular adrenergic and cholinergic receptors, we concluded that: Non-vascular smooth muscles (vas deferens) are less sensitive to irradiation in comparing with vascular smooth muscles (venae portal hepatica), and irradiation increases the sensitivity of cholinergic receptors to acetylcholine in the smooth muscular fibers of vas deferens while; if decreases this sensitivity in the smooth muscular fibers of venae portal hepatica

[Effects of low molecular weight heparin on the inflammatory response and vascular injury in rat after electric burn].

Science.gov (United States)

Jiang, Nanhong; Xie, Weiguo; Wang, Hui; Jin, Dongmei; Tan, Hong; Zhao, Chaoli

2014-04-01

To observe the effects of low molecular weight heparin (LMWH) on the inflammatory response and vascular injury in rat after electric burn. A homemade regulator and transformer apparatus was used to reproduce the model of electric burn (0.5 cm×0.5 cm in size) with depth from full-thickness to full-thickness skin plus muscle and bone on the middle of the inside of right hind limb in 60 Wistar rats. The open wounds were covered with 20 g/L sulfadiazine silver paste immediately after injury. The wound condition was observed every day. The injured rats were divided into group LMWH and control group (C) according to the random number table, with 30 rats in each group. Rats in group LMWH were given subcutaneous injection of LMWH (1 U/g) in abdominal wall, 2 times a day. No other treatment was given in rats in group C. On post burn day (PBD) 3, 5, and 10, 10 rats respectively of two groups were sacrificed. The damaged tissue of wound and that around the wound (1.0 cm×0.5 cm in size) were excised, and heart blood was obtained. The pathological changes and thrombosis in damaged tissue were observed with HE, Masson, and aldehyde fuchsin staining, and the thrombosis rate was calculated. Serum contents of TNF-α and endothelin-1 were determined with ELISA. The mRNA expression of TNF-α in damaged tissue was detected with RT-PCR. Data were processed with Levene homogeneity test, analysis of variance of factorial design, LSD- t test, SNK- q test, and Friedman M nonparametric test. (1) The injured limb of rats was obviously swollen after electric burn, which reached deeply to the muscle and bone. Compared with those of group C, the swelling of rats subsided slightly faster and the inflammatory response was lighter in group LMWH at each time point. (2) The necrosis of damaged tissue and profuse infiltration of inflammatory cells were observed. Dilatation of blood vessels, congestion and thrombosis, and swelling, necrosis, and desquamation of vascular endothelial cells were

Effect of tamoxifen on the coronary vascular reactivity of spontaneously hypertensive female rats

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M.V. Borgo

2011-08-01

Full Text Available Tamoxifen has been associated with a reduction in the incidence of myocardial infarction. However, the effects of tamoxifen on coronary reactivity have not been fully elucidated. The objective of this study was to determine the effects of chronic treatment with tamoxifen on coronary vascular reactivity in spontaneously hypertensive rats (SHR. Female SHR were divided into four groups (N = 7 each: sham-operated (SHAM, sham-operated and treated with tamoxifen (10 mg/kg by gavage for 90 days (TAMOX, ovariectomized (OVX, and ovariectomized and treated with tamoxifen (OVX+TAMOX. Mean arterial pressure (MAP, heart rate (HR, coronary perfusion pressure (CPP, and coronary vascular reactivity were measured. MAP and HR were reduced (9.42 and 11.67%, respectively in the OVX+TAMOX group compared to the OVX group (P < 0.01. The coronary vascular reactivity of the OVX+TAMOX group presented smaller vasoconstrictor responses to acetylcholine (2-64 µg when compared to the OVX group (P < 0.01 and this response was similar to that of the SHAM group. The adenosine-induced vasodilator response was greater in the TAMOX group compared to the SHAM and OVX groups (P < 0.05. Baseline CPP was higher in OVX+TAMOX and TAMOX groups (136 ± 3.6 and 130 ± 1.5 mmHg than in OVX and SHAM groups (96 ± 2 and 119 ± 2.3 mmHg; P < 0.01. Tamoxifen, when combined with OVX, attenuated the vasoconstriction induced by acetylcholine and increased the adenosine-induced vasodilatory response, as well as reducing the MAP, suggesting beneficial effects of tamoxifen therapy on coronary vascular reactivity after menopause.

Non-invasive stem cell therapy in a rat model for retinal degeneration and vascular pathology.

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Shaomei Wang

Full Text Available BACKGROUND: Retinitis pigmentosa (RP is characterized by progressive night blindness, visual field loss, altered vascular permeability and loss of central vision. Currently there is no effective treatment available except gene replacement therapy has shown promise in a few patients with specific gene defects. There is an urgent need to develop therapies that offer generic neuro-and vascular-protective effects with non-invasive intervention. Here we explored the potential of systemic administration of pluripotent bone marrow-derived mesenchymal stem cells (MSCs to rescue vision and associated vascular pathology in the Royal College Surgeons (RCS rat, a well-established animal model for RP. METHODOLOGY/PRINCIPAL FINDINGS: Animals received syngeneic MSCs (1x10(6 cells by tail vein at an age before major photoreceptor loss. PRINCIPAL RESULTS: both rod and cone photoreceptors were preserved (5-6 cells thick at the time when control animal has a single layer of photoreceptors remained; Visual function was significantly preserved compared with controls as determined by visual acuity and luminance threshold recording from the superior colliculus; The number of pathological vascular complexes (abnormal vessels associated with migrating pigment epithelium cells and area of vascular leakage that would ordinarily develop were dramatically reduced; Semi-quantitative RT-PCR analysis indicated there was upregulation of growth factors and immunohistochemistry revealed that there was an increase in neurotrophic factors within eyes of animals that received MSCs. CONCLUSIONS/SIGNIFICANCE: These results underscore the potential application of MSCs in treating retinal degeneration. The advantages of this non-invasive cell-based therapy are: cells are easily isolated and can be expanded in large quantity for autologous graft; hypoimmunogenic nature as allogeneic donors; less controversial in nature than other stem cells; can be readministered with minor discomfort

Chromosome preparations from microplate cultures of man, dog, rat, and mouse

NARCIS (Netherlands)

de Jong, B; Anders, GJPA; van der Meer, Ingrid H

1976-01-01

A simple method for making chromosomal preparations from 105 leukocytes from man, dog, mouse, and rat and from 0.01 ml total human and dog blood is developed. The leukocytes and the peripheral blood are cultured in Cooke microtiter plates in a culture volume of 0.1 ml. The culture medium is R.P.M.I.

In vitro differentiation of rat spermatogonia into round spermatids in tissue culture.

Science.gov (United States)

Reda, A; Hou, M; Winton, T R; Chapin, R E; Söder, O; Stukenborg, J-B

2016-09-01

Do the organ culture conditions, previously defined for in vitro murine male germ cell differentiation, also result in differentiation of rat spermatogonia into post-meiotic germ cells exhibiting specific markers for haploid germ cells? We demonstrated the differentiation of rat spermatogonia into post-meiotic cells in vitro, with emphasis on exhibiting, protein markers described for round spermatids. Full spermatogenesis in vitro from immature germ cells using an organ culture technique in mice was first reported 5 years ago. However, no studies reporting the differentiation of rat spermatogonia into post-meiotic germ cells exhibiting the characteristic protein expression profile or into functional sperm have been reported. Organ culture of testicular fragments of 5 days postpartum (dpp) neonatal rats was performed for up to 52 days. Evaluation of microscopic morphology, testosterone levels, mRNA and protein expression as measured by RT-qPCR and immunostaining were conducted to monitor germ cell differentiation in vitro. Potential effects of melatonin, Glutamax® medium, retinoic acid and the presence of epidydimal fat tissue on the spermatogenic process were evaluated. A minimum of three biological replicates were performed for all experiments presented in this study. One-way ANOVA, ANOVA on ranks and student's t-test were applied to perform the statistical analysis. Male germ cells, present in testicular tissue pieces grown from 5 dpp rats, exhibited positive protein expression for Acrosin and Crem (cAMP (cyclic adenosine mono phosphate) response element modulator) after 52 days of culture in vitro. Intra-testicular testosterone production could be observed after 3 days of culture, while when epididymal fat tissue was added, spontaneous contractility of cultured seminiferous tubules could be observed after 21 days. However, no supportive effect of the supplementation with any factor or the co-culturing with epididymal fat tissue on germ cell differentiation in

Aluminum exposure for one hour decreases vascular reactivity in conductance and resistance arteries in rats

International Nuclear Information System (INIS)

Schmidt, Patrícia Medeiros; Escobar, Alyne Goulart; Torres, João Guilherme Dini; Martinez, Caroline Silveira; Rizzetti, Danize Aparecida; Kunz, Simone Noremberg; Vassallo, Dalton Valentim; Alonso, María Jesús; Peçanha, Franck Maciel; Wiggers, Giulia Alessandra

2016-01-01

Aims: Aluminum (Al) is an important environmental contaminant; however, there are not enough evidences of Al-induced cardiovascular dysfunction. We investigated the effects of acute exposure to aluminum chloride (AlCl 3 ) on blood pressure, vascular reactivity and oxidative stress. Methods and results: Male Wistar rats were divided into two groups: Untreated: vehicle (ultrapure water, ip) and AlCl 3 : single dose of AlCl 3 (100 mg/kg,ip). Concentration-response curves to phenylephrine in the absence and presence of endothelium, the nitric oxide synthase inhibitor L-NAME, the potassium channel blocker tetraethylammonium, and the NADPH oxidase inhibitor apocynin were performed in segments from aortic and mesenteric resistance arteries. NO released was assessed in aorta and reactive oxygen species (ROS), malondialdehyde, non-protein thiol levels, antioxidant capacity and enzymatic antioxidant activities were investigated in plasma, aorta and/or mesenteric arteries. After one hour of AlCl 3 exposure serum Al levels attained 147.7 ± 25.0 μg/L. Al treatment: 1) did not affect blood pressure, heart rate and vasodilator responses induced by acetylcholine or sodium nitroprusside; 2) decreased phenylephrine-induced vasoconstrictor responses; 3) increased endothelial modulation of contractile responses, NO release and vascular ROS production from NADPH oxidase; 4) increased plasmatic, aortic and mesenteric malondialdehyde and ROS production, and 5) decreased antioxidant capacity and affected the antioxidant biomarkers non-protein thiol levels, glutathione peroxidase, glutathione-S-transferase, superoxide dismutase and catalase enzymatic activities. Conclusion: AlCl 3 -acute exposure reduces vascular reactivity. This effect is associated with increased NO production, probably acting on K + channels, which seems to occur as a compensatory mechanism against Al-induced oxidative stress. Our results suggest that Al exerts toxic effects to the vascular system. - Highlights: �

Aluminum exposure for one hour decreases vascular reactivity in conductance and resistance arteries in rats

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Patrícia Medeiros; Escobar, Alyne Goulart; Torres, João Guilherme Dini; Martinez, Caroline Silveira; Rizzetti, Danize Aparecida; Kunz, Simone Noremberg [Postgraduate Program in Biochemistry, Universidade Federal do Pampa, Uruguaiana, Rio Grande do Sul (Brazil); Vassallo, Dalton Valentim [Department of Physiological Sciences, Universidade Federal do Espírito Santo, Espirito Santo (Brazil); Alonso, María Jesús [Department of Basic Health Sciences, Universidad Rey Juan Carlos, Alcorcón (Spain); Peçanha, Franck Maciel [Postgraduate Program in Biochemistry, Universidade Federal do Pampa, Uruguaiana, Rio Grande do Sul (Brazil); Wiggers, Giulia Alessandra, E-mail: giuliawp@gmail.com [Postgraduate Program in Biochemistry, Universidade Federal do Pampa, Uruguaiana, Rio Grande do Sul (Brazil)

2016-12-15

Aims: Aluminum (Al) is an important environmental contaminant; however, there are not enough evidences of Al-induced cardiovascular dysfunction. We investigated the effects of acute exposure to aluminum chloride (AlCl{sub 3}) on blood pressure, vascular reactivity and oxidative stress. Methods and results: Male Wistar rats were divided into two groups: Untreated: vehicle (ultrapure water, ip) and AlCl{sub 3}: single dose of AlCl{sub 3} (100 mg/kg,ip). Concentration-response curves to phenylephrine in the absence and presence of endothelium, the nitric oxide synthase inhibitor L-NAME, the potassium channel blocker tetraethylammonium, and the NADPH oxidase inhibitor apocynin were performed in segments from aortic and mesenteric resistance arteries. NO released was assessed in aorta and reactive oxygen species (ROS), malondialdehyde, non-protein thiol levels, antioxidant capacity and enzymatic antioxidant activities were investigated in plasma, aorta and/or mesenteric arteries. After one hour of AlCl{sub 3} exposure serum Al levels attained 147.7 ± 25.0 μg/L. Al treatment: 1) did not affect blood pressure, heart rate and vasodilator responses induced by acetylcholine or sodium nitroprusside; 2) decreased phenylephrine-induced vasoconstrictor responses; 3) increased endothelial modulation of contractile responses, NO release and vascular ROS production from NADPH oxidase; 4) increased plasmatic, aortic and mesenteric malondialdehyde and ROS production, and 5) decreased antioxidant capacity and affected the antioxidant biomarkers non-protein thiol levels, glutathione peroxidase, glutathione-S-transferase, superoxide dismutase and catalase enzymatic activities. Conclusion: AlCl{sub 3}-acute exposure reduces vascular reactivity. This effect is associated with increased NO production, probably acting on K{sup +} channels, which seems to occur as a compensatory mechanism against Al-induced oxidative stress. Our results suggest that Al exerts toxic effects to the vascular

Advanced glycation end products promote the proliferation and migration of primary rat vascular smooth muscle cells via the upregulation of BAG3.

Science.gov (United States)

Li, Cunshu; Chang, Ye; Li, Yuan; Chen, Shuang; Chen, Yintao; Ye, Ning; Dai, Dongxue; Sun, Yingxian

2017-05-01

The present study was aimed to investigate the role of reactive oxygen species (ROS) on advanced glycation end product (AGE)-induced proliferation and migration of vascular smooth muscle cells (VSMCs) and whether Bcl-2‑associated athanogene 3 (BAG3) is involved in the process. Primary rat VSMCs were extracted and cultured in vitro. Cell viability was detected by MTT assay and cell proliferation was detected by EdU incorporation assay. Cell migration was detected by wound healing and Transwell assays. BAG3 was detected using qPCR and western blot analysis. Transcriptional and translational inhibitors (actinomycin D and cycloheximide, respectively) were used to study the effect of AGEs on the expression of BAG3 in VSMCs. Lentiviral plasmids containing short hairpin RNA (shRNA) against rat BAG3 or control shRNA were transduced into VSMCs. Cellular ROS were detected by 2',7'-dichlorofluorescein diacetate (DCFH-DA) staining. Mitochondrial membrane potential was detected by tetramethylrhodamine methyl ester (TMRE) staining. AGEs significantly increased the expression of BAG3 in a dose-and time-dependent manner. Furthermore, AGEs mainly increased the expression of BAG3 mRNA by increasing the RNA synthesis rather than inhibiting the RNA translation. BAG3 knockdown reduced the proliferation and migration of VSMCs induced by AGEs. BAG3 knockdown reduced the generation of ROS and sustained the mitochondrial membrane potential of VSMCs. Reduction of ROS production by N-acetylcysteine (NAC), a potent antioxidant, also reduced the proliferation and migration of VSMCs. On the whole, the present study demonstrated for the first time that AGEs could increase ROS production and promote the proliferation and migration of VSMCs by upregulating BAG3 expression. This study indicated that BAG3 should be considered as a potential target for the prevention and/or treatment of vascular complications of diabetes.

Trimethyltin (TMT) neurotoxicity in organotypic rat hippocampal slice cultures

DEFF Research Database (Denmark)

Noraberg, J; Gramsbergen, J B; Fonnum, F

1998-01-01

) propidium iodide (PI) uptake, (b) lactate dehydrogenase (LDH) efflux into the culture medium, (c) cellular cobalt uptake as an index of calcium influx, (d) ordinary Nissl cell staining, and (e) immunohistochemical staining for microtubule-associated protein 2 (MAP-2). Cellular degeneration as assessed...... to in vivo cell stain observations of rats acutely exposed to TMT. The mean PI uptake of the cultures and the LDH efflux into the medium were highly correlated. The combined results obtained by the different markers indicate that the hippocampal slice culture method is a feasible model for further studies...

3D printed scaffolds of calcium silicate-doped β-TCP synergize with co-cultured endothelial and stromal cells to promote vascularization and bone formation.

Science.gov (United States)

Deng, Yuan; Jiang, Chuan; Li, Cuidi; Li, Tao; Peng, Mingzheng; Wang, Jinwu; Dai, Kerong

2017-07-17

Synthetic bone scaffolds have potential application in repairing large bone defects, however, inefficient vascularization after implantation remains the major issue of graft failure. Herein, porous β-tricalcium phosphate (β-TCP) scaffolds with calcium silicate (CS) were 3D printed, and pre-seeded with co-cultured human umbilical cord vein endothelial cells (HUVECs) and human bone marrow stromal cells (hBMSCs) to construct tissue engineering scaffolds with accelerated vascularization and better bone formation. Results showed that in vitro β-TCP scaffolds doped with 5% CS (5%CS/β-TCP) were biocompatible, and stimulated angiogenesis and osteogenesis. The results also showed that 5%CS/β-TCP scaffolds not only stimulated co-cultured cells angiogenesis on Matrigel, but also stimulated co-cultured cells to form microcapillary-like structures on scaffolds, and promoted migration of BMSCs by stimulating co-cultured cells to secrete PDGF-BB and CXCL12 into the surrounding environment. Moreover, 5%CS/β-TCP scaffolds enhanced vascularization and osteoinduction in comparison with β-TCP, and synergized with co-cultured cells to further increase early vessel formation, which was accompanied by earlier and better ectopic bone formation when implanted subcutaneously in nude mice. Thus, our findings suggest that porous 5%CS/β-TCP scaffolds seeded with co-cultured cells provide new strategy for accelerating tissue engineering scaffolds vascularization and osteogenesis, and show potential as treatment for large bone defects.

Ameliorative effect of combination of benfotiamine and fenofibrate in diabetes-induced vascular endothelial dysfunction and nephropathy in the rat.

Science.gov (United States)

Balakumar, Pitchai; Chakkarwar, Vishal Arvind; Singh, Manjeet

2009-01-01

The study has been designed to investigate the effect of benfotiamine and fenofibrate in diabetes-induced experimental vascular endothelial dysfunction (VED) and nephropathy. The single administration of streptozotocin (STZ) (50 mg/kg, i.p.) produced diabetes, which was noted to develop VED and nephropathy in 8 weeks. The diabetes produced VED by attenuating acetylcholine-induced endothelium dependent relaxation, impairing the integrity of vascular endothelium, decreasing serum nitrite/nitrate concentration and increasing serum TBARS and aortic superoxide anion generation. Further, diabetes altered the lipid profile by increasing the serum cholesterol, triglycerides and decreasing the high density lipoprotein. The nephropathy was noted to be developed in the diabetic rat that was assessed in terms of increase in serum creatinine, blood urea, proteinuria, and glomerular damage. The benfotiamine (70 mg/kg, p.o.) and fenofibrate (32 mg/kg, p.o.) or lisinopril (1 mg/kg, p.o., a standard agent) treatments were started in diabetic rats after 1 week of STZ administration and continued for 7 weeks. The treatment with benfotiamine and fenofibrate either alone or in combination attenuated diabetes-induced VED and nephropathy. In addition, the combination of benfotiamine and fenofibrate was noted to be more effective in attenuating the diabetes-induced VED and nephropathy when compared to treatment with either drug alone or lisinopril. Treatment with fenofibrate normalizes the altered lipid profile in diabetic rats, whereas benfotiamine treatment has no effect on lipid alteration in diabetic rats. It may be concluded that diabetes-induced oxidative stress, lipids alteration, and consequent development of VED may be responsible for the induction of nephropathy in diabetic rats. Concurrent administration of benfotiamine and fenofibrate may provide synergistic benefits in preventing the development of diabetes-induced nephropathy by reducing the oxidative stress and lipid

Augmented vascular smooth muscle cell stiffness and adhesion when hypertension is superimposed on aging.

Science.gov (United States)

Sehgel, Nancy L; Sun, Zhe; Hong, Zhongkui; Hunter, William C; Hill, Michael A; Vatner, Dorothy E; Vatner, Stephen F; Meininger, Gerald A

2015-02-01

Hypertension and aging are both recognized to increase aortic stiffness, but their interactions are not completely understood. Most previous studies have attributed increased aortic stiffness to changes in extracellular matrix proteins that alter the mechanical properties of the vascular wall. Alternatively, we hypothesized that a significant component of increased vascular stiffness in hypertension is due to changes in the mechanical and adhesive properties of vascular smooth muscle cells, and that aging would augment the contribution from vascular smooth muscle cells when compared with the extracellular matrix. Accordingly, we studied aortic stiffness in young (16-week-old) and old (64-week-old) spontaneously hypertensive rats and Wistar-Kyoto wild-type controls. Systolic and pulse pressures were significantly increased in young spontaneously hypertensive rats when compared with young Wistar-Kyoto rats, and these continued to rise in old spontaneously hypertensive rats when compared with age-matched controls. Excised aortic ring segments exhibited significantly greater elastic moduli in both young and old spontaneously hypertensive rats versus Wistar-Kyoto rats. were isolated from the thoracic aorta, and stiffness and adhesion to fibronectin were measured by atomic force microscopy. Hypertension increased both vascular smooth muscle cell stiffness and vascular smooth muscle cell adhesion, and these increases were both augmented with aging. By contrast, hypertension did not affect histological measures of aortic collagen and elastin, which were predominantly changed by aging. These findings support the concept that stiffness and adhesive properties of vascular smooth muscle cells are novel mechanisms contributing to the increased aortic stiffness occurring with hypertension superimposed on aging. © 2014 American Heart Association, Inc.

Emerging Role of Angiotensin Type 2 Receptor (AT2R)/Akt/NO Pathway in Vascular Smooth Muscle Cell in the Hyperthyroidism

Science.gov (United States)

Carrillo-Sepúlveda, Maria Alícia; Ceravolo, Graziela S.; Furstenau, Cristina R.; Monteiro, Priscilla de Souza; Bruno-Fortes, Zuleica; Carvalho, Maria Helena; Laurindo, Francisco R.; Tostes, Rita C.; Webb, R. Clinton; Barreto-Chaves, Maria Luiza M.

2013-01-01

Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3) that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC) relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS) plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R), a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper). These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC). Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII), which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L) for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium. PMID:23637941

Emerging role of angiotensin type 2 receptor (AT2R/Akt/NO pathway in vascular smooth muscle cell in the hyperthyroidism.

Directory of Open Access Journals (Sweden)

Maria Alícia Carrillo-Sepúlveda

Full Text Available Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3 that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R, a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper. These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC. Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII, which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium.

Inability of donor total body irradiation to prolong survival of vascularized bone allografts: Experimental study in the rat

International Nuclear Information System (INIS)

Gonzalez del Pino, J.; Benito, M.; Randolph, M.A.; Weiland, A.J.

1990-01-01

At the present time, the toxic side effects of recipient immunosuppression cannot be justified for human non-vital organ transplantation. Total body irradiation has proven effective in ablating various bone-marrow-derived and endothelial immunocompetent cellular populations, which are responsible for immune rejection against donor tissues. Irradiation at a dose of 10 Gy was given to donor rats six days prior to heterotopic transplantation of vascularized bone allografts to host animals. Another group of recipient rats also received a short-term (sixth to fourteenth day after grafting), low dose of cyclosporine. Total body irradiation was able merely to delay rejection of grafts across a strong histocompatibility barrier for one to two weeks, when compared to nonirradiated allografts. The combination of donor irradiation plus cyclosporine did not delay the immune response, and the rejection score was similar to that observed for control allografts. Consequently, allograft viability was quickly impaired, leading to irreversible bone damage. This study suggest that 10 Gy of donor total body irradiation delivered six days prior to grafting cannot circumvent the immune rejection in a vascularized allograft of bone across a strong histocompatibility barrier

Effects of Mild Blast Traumatic Brain Injury on Cerebral Vascular, Histopathological, and Behavioral Outcomes in Rats

Science.gov (United States)

Zeng, Yaping; Deyo, Donald; Parsley, Margaret A.; Hawkins, Bridget E.; Prough, Donald S.; DeWitt, Douglas S.

2018-01-01

Abstract To determine the effects of mild blast-induced traumatic brain injury (bTBI), several groups of rats were subjected to blast injury or sham injury in a compressed air-driven shock tube. The effects of bTBI on relative cerebral perfusion (laser Doppler flowmetry [LDF]), and mean arterial blood pressure (MAP) cerebral vascular resistance were measured for 2 h post-bTBI. Dilator responses to reduced intravascular pressure were measured in isolated middle cerebral arterial (MCA) segments, ex vivo, 30 and 60 min post-bTBI. Neuronal injury was assessed (Fluoro-Jade C [FJC]) 24 and 48 h post-bTBI. Neurological outcomes (beam balance and walking tests) and working memory (Morris water maze [MWM]) were assessed 2 weeks post-bTBI. Because impact TBI (i.e., non-blast TBI) is often associated with reduced cerebral perfusion and impaired cerebrovascular function in part because of the generation of reactive oxygen and nitrogen species such as peroxynitrite (ONOO−), the effects of the administration of the ONOO− scavenger, penicillamine methyl ester (PenME), on cerebral perfusion and cerebral vascular resistance were measured for 2 h post-bTBI. Mild bTBI resulted in reduced relative cerebral perfusion and MCA dilator responses to reduced intravascular pressure, increases in cerebral vascular resistance and in the numbers of FJC-positive cells in the brain, and significantly impaired working memory. PenME administration resulted in significant reductions in cerebral vascular resistance and a trend toward increased cerebral perfusion, suggesting that ONOO− may contribute to blast-induced cerebral vascular dysfunction. PMID:29160141

Electropuncture influences on learning, memory, and neuropeptide expression in a rat model of vascular dementia

Institute of Scientific and Technical Information of China (English)

Ying Shao; Yanqian Fu; Lihua Qiu; Bing Yan; Xinsheng Lai; Chunzhi Tang

2008-01-01

BACKGROUND: Studies in recent years have indicated that several neuropeptide-like substances, such as arginine vasopressin (AVP), somatostatin (SS), and β-endorphine (β-EP), are involved in the process of cerebral ischemic damage to cranial nerves.OBJECTIVE: To observe the effects of electropuncture on back-shu points, as well as the influence on learning and memory, AVP, SS, and β-EP levels in plasma and brain were measured in a rat model of vascular dementia (VD). DESIGN: Randomized controlled trial.SETTING: College of Acupuncture and Massage of Guangzhou University of Chinese Medicine.MATERIALS: This experiment was performed at the Animal Experiment Center of Guangzhou University of TCM from December 2005 to December 2006. A total of 48 healthy adult male Sprague Dawley rats of SPF-grade, 180-220 g, were provided by The Animal Experiment Center of Guangzhou University of Traditional Chinese Medicine. The following instruments were used: SDQ-30 Dipolar Radio-frequency Electrocoagulator (Shanghai Operation Instrument Factory), Morris Water Maze (The Animal Experiment Center of Guangzhou University of Traditional Chinese Medicine), Type G6805-1 Treating Equipment (Huasheng Equipment Factory, Qingdao, China).METHODS: ① Eight rats were randomly selected for the control group; the remaining 40 rats underwent 4-vascular occlusion to establish a cerebral ischemia model. Due to the death of 13 rats and 2 hemiplegies during model establishment, there was a total of 25 model rats available for testing. The model rats were divided randomly into 3 groups according to their body weight: electropuncture group (n = 9), medication group (n = 8), and VD group (n = 8). ② Electropuncture group: 25 mm needles (28 gauge) were used to electropuncture (150 Hz, continuous waves, 1.0-2.0 mA, duration of 20 minutes) the following acupoints: Baihui (GV20), Geshu (BL17), Pishu (BL20), and Shenshu (BL23). The acupoints were located according to Experimental acupuncturology and were

Cartilage oligomeric matrix protein enhances the vascularization of acellular nerves

Directory of Open Access Journals (Sweden)

Wei-ling Cui

2016-01-01

Full Text Available Vascularization of acellular nerves has been shown to contribute to nerve bridging. In this study, we used a 10-mm sciatic nerve defect model in rats to determine whether cartilage oligomeric matrix protein enhances the vascularization of injured acellular nerves. The rat nerve defects were treated with acellular nerve grafting (control group alone or acellular nerve grafting combined with intraperitoneal injection of cartilage oligomeric matrix protein (experimental group. As shown through two-dimensional imaging, the vessels began to invade into the acellular nerve graft from both anastomotic ends at day 7 post-operation, and gradually covered the entire graft at day 21. The vascular density, vascular area, and the velocity of revascularization in the experimental group were all higher than those in the control group. These results indicate that cartilage oligomeric matrix protein enhances the vascularization of acellular nerves.

Transplantation of endothelial progenitor cells ameliorates vascular dysfunction and portal hypertension in carbon tetrachloride-induced rat liver cirrhotic model.

Science.gov (United States)

Sakamoto, Masaharu; Nakamura, Toru; Torimura, Takuji; Iwamoto, Hideki; Masuda, Hiroshi; Koga, Hironori; Abe, Mitsuhiko; Hashimoto, Osamu; Ueno, Takato; Sata, Michio

2013-01-01

In cirrhosis, sinusoidal endothelial cell injury results in increased endothelin-1 (ET-1) and decreased nitric oxide synthase (NOS) activity, leading to portal hypertension. However, the effects of transplanted endothelial progenitor cells (EPCs) on the cirrhotic liver have not yet been clarified. We investigated whether EPC transplantation reduces portal hypertension. Cirrhotic rats were created by the administration of carbon tetrachloride (CCl(4) ) twice weekly for 10 weeks. From week 7, rat bone marrow-derived EPCs were injected via the tail vein in this model once a week for 4 weeks. Endothelial NOS (eNOS), vascular endothelial growth factor (VEGF) and caveolin expressions were examined by Western blots. Hepatic tissue ET-1 was measured by a radioimmunoassay (RIA). Portal venous pressure, mean aortic pressure, and hepatic blood flow were measured. Endothelial progenitor cell transplantation reduced liver fibrosis, α-smooth muscle actin-positive cells, caveolin expression, ET-1 concentration and portal venous pressure. EPC transplantation increased hepatic blood flow, protein levels of eNOS and VEGF. Immunohistochemical analyses of eNOS and isolectin B4 demonstrated that the livers of EPC-transplanted animals had markedly increased vascular density, suggesting reconstitution of sinusoidal blood vessels with endothelium. Transplantation of EPCs ameliorates vascular dysfunction and portal hypertension, suggesting this treatment may provide a new approach in the therapy of portal hypertension with liver cirrhosis. © 2012 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

Diabetes increases susceptibility of primary cultures of rat proximal tubular cells to chemically induced injury

International Nuclear Information System (INIS)

Zhong Qing; Terlecky, Stanley R.; Lash, Lawrence H.

2009-01-01

Diabetic nephropathy is characterized by increased oxidative stress and mitochondrial dysfunction. In the present study, we prepared primary cultures of proximal tubular (PT) cells from diabetic rats 30 days after an ip injection of streptozotocin and compared their susceptibility to oxidants (tert-butyl hydroperoxide, methyl vinyl ketone) and a mitochondrial toxicant (antimycin A) with that of PT cells isolated from age-matched control rats, to test the hypothesis that PT cells from diabetic rats exhibit more cellular and mitochondrial injury than those from control rats when exposed to these toxicants. PT cells from diabetic rats exhibited higher basal levels of reactive oxygen species (ROS) and higher mitochondrial membrane potential, demonstrating that the PT cells maintain the diabetic phenotype in primary culture. Incubation with either the oxidants or mitochondrial toxicant resulted in greater necrotic and apoptotic cell death, greater evidence of morphological damage, greater increases in ROS, and greater decreases in mitochondrial membrane potential in PT cells from diabetic rats than in those from control rats. Pretreatment with either the antioxidant N-acetyl-L-cysteine or a catalase mimetic provided equivalent protection of PT cells from both diabetic and control rats. Despite the greater susceptibility to oxidative and mitochondrial injury, both cytoplasmic and mitochondrial glutathione concentrations were markedly higher in PT cells from diabetic rats, suggesting an upregulation of antioxidant processes in diabetic kidney. These results support the hypothesis that primary cultures of PT cells from diabetic rats are a valid model in which to study renal cellular function in the diabetic state.

Study on the effect of hypoxia on apoptosis of cultured newly born rat cardiac myocytes

International Nuclear Information System (INIS)

Su Weidong; Li Huiqiang; Yao Zhi

2005-01-01

Objective: To investigate the possible hypoxia-mediated cellular apoptosis after ischemic cardiac injury via a model of cultured newly born rat cardiac myocytes. Methods: Cardiac myocytes cultures from newly born rats (1-3d) were examined for apoptosis with HE stain and flow cytometry after cultured 96h and again examined after exposure to hypoxic environment for 16h. Results: Apoptotic changes were evident in the hypoxic culture cells. The HE stain revealed cellular shrinkage, nuclear chromosomal condensation with cytoplasmic eosinophilia. Also, distinct apoptosis peak was observed in the flow cytometry. Conclusion: This experiment proved that hypoxic model of cardiac myocyte culture showed definite apoptosis of the cells. (authors)

Acupuncture attenuates cognitive deficits and increases pyramidal neuron number in hippocampal CA1 area of vascular dementia rats.

Science.gov (United States)

Li, Fang; Yan, Chao-Qun; Lin, Li-Ting; Li, Hui; Zeng, Xiang-Hong; Liu, Yi; Du, Si-Qi; Zhu, Wen; Liu, Cun-Zhi

2015-04-28

Decreased cognition is recognized as one of the most severe and consistent behavioral impairments in dementia. Experimental studies have reported that acupuncture may improve cognitive deficits, relieve vascular dementia (VD) symptoms, and increase cerebral perfusion and electrical activity. Multi-infarction dementia was modeled in rats with 3% microemboli saline suspension. Two weeks after acupuncture at Zusanli (ST36), all rats were subjected to a hidden platform trial to test their 3-day spatial memory using the Morris water maze test. To estimate the numbers of pyramidal neuron, astrocytes, and synaptic boutons in hippocampal CA1 area, we adopted an unbiased stereology method to accurately sample and measure the size of cells. We found that acupuncture at ST36 significantly decreased the escape latency of VD rats. In addition, acupuncture significantly increased the pyramidal neuron number in hippocampal CA1 area (P area in any of the groups (P > 0.05). These findings suggest that acupuncture may improve cognitive deficits and increase pyramidal neuron number of hippocampal CA1 area in VD rats.

Cross-cultural validation of the Prosthesis Evaluation Questionnaire in vascular amputees fitted with prostheses in Spain.

Science.gov (United States)

Benavent, Jose Vicente; Igual, Celedonia; Mora, Enrique; Antonio, Rosa; Tenias, Jose Maria

2016-12-01

The lack of specific prosthetic-related outcome instruments for Spanish amputees must be addressed. To elaborate a culturally equivalent version of the Prosthesis Evaluation Questionnaire in the Spanish language. Cross-cultural questionnaire validation. Two-step process for cultural adaptation: forward and backward translations of English original and Spanish translated versions; assessment of both construct and criterion validity and reliability in a group of vascular amputees. A total of 61 patients were recruited, 44 men (72.1%) and 17 women (27.9%), with a median age of 71.1 years (standard deviation: 7.7 years; range: 51-87 years). In the Prosthesis Evaluation Questionnaire-Spanish, the lowest scores were for gait and frustration, and the highest scores were for noise and stump health. Internal consistency of the questionnaire was acceptable (>0.70) for four of the scales used in the Prosthesis Evaluation Questionnaire but poor (<0.50) for the scales relating to appearance and stump health. Correlations with the quality-of-life levels as measured by the Short Form-36 were positive and mostly significant. Prosthesis Evaluation Questionnaire-Spanish could assess the quality of life in patients who have undergone vascular amputations and then been fitted with a prosthetic limb. The questionnaire shows adequate criteria validity when compared with other instruments for measuring quality of life. The Prosthesis Evaluation Questionnaire-Spanish could be a valid and reliable instrument for assessing adaptation to prostheses in vascular amputees. The questionnaire adds information relevant to the patient and the physician and may identify cases with poor expected adaptation to the prosthesis. © The International Society for Prosthetics and Orthotics 2015.

Increased Expression of Intercellular Adhesion Molecule-1, Vascular Cellular Adhesion Molecule-1 and Leukocyte Common Antigen in Diabetic Rat Retina

Institute of Scientific and Technical Information of China (English)

Ningyan Bai; Shibo Tang; Jing Ma; Yan Luo; Shaofeng Lin

2003-01-01

Purpose: To understand the expression and distribution of intercellular adhesion molecule- 1(ICAM- 1),vascular cellular adhesion molecule- 1 (VCAM- 1)and CD45 (Leukocyte Common Antigen) in the control nondiabetic and various courses of diabetic rats retina. To explore the role of adhesion molecules (Ams) and the adhesion of leukocytes to vascular endothelial cells via Ams in diabetic retinopathy(DR).Methods: Sixty healthy adult male Wistar rats were randomly divided into diabetic groups(induced by Streptozotocin, STZ) and normal control groups. Rats in these two groups were further randomly divided into 3, 7, 14, 30, 90 and 180 days-group,including 5 rats respectively. The immunohistochemical studies of ICAM-1, VCAM-1 and CD45 were carried out in the retinal digest preparations or retinal paraffin sections, and the results were analyzed qualitatively, semi-quantitatively.Results: No positive reaction of VCAM-1 was found, and weak reactions of ICAM-1,CD45 were found in nondiabetic rats retina. The difference of 6 control groups had no statistical significance(P ＞ 0.05). The increased ICAM-1 and CD45 staining pattern were detectable 3 days after diabetes induction, and a few VCAM-1 positive cells were observed in the retinal blood capillaries. The difference of diabetes and control is significant( P ＜ 0.05).Following the course, the expressions of ICAM-1, VCAM-1 and CD45 were increasingly enhanced, reaching a peak at the 14th day.Conclusion: Increased expression of ICAM-1, VCAM-1 and leukocytes adhering and stacking in retinal capillaries are the very early events in DR. Coherence of expression and distribution of the three further accounts for it is the key point for the onset of DR that Ams mediates leukocytes adhesion and endothelial cell injury.

Uptake of thyroxine in cultured anterior pituitary cells of euthyroid rats

NARCIS (Netherlands)

M.E. Everts (Maria); R. Docter (Roel); E.P.C.M. Moerings (Ellis); P.M. van Koetsveld (Peter); T.J. Visser (Theo); E.P. Krenning (Eric); G. Hennemann; M. de Jong (Marcel)

1994-01-01

textabstractThe uptake of [125I]T4 was investigated in cultured anterior pituitary cells isolated from adult fed Wistar rats and cultured for 3 days in medium containing 10% fetal calf serum. Experiments were performed with [125I]T4 (10(5) to 2 x 10(6) cpm; 0.35-7 nM)

Vascular graft infections with Mycoplasma

DEFF Research Database (Denmark)

Levi-Mazloum, Niels Donald; Skov Jensen, J; Prag, J

1995-01-01

laboratory techniques, the percentage of culture-negative yet grossly infected vascular grafts seems to be increasing and is not adequately explained by the prior use of antibiotics. We have recently reported the first case of aortic graft infection with Mycoplasma. We therefore suggest the hypothesis...... that the large number of culture-negative yet grossly infected vascular grafts may be due to Mycoplasma infection not detected with conventional laboratory technique....

Felodipine attenuates vascular inflammation in a fructose-induced rat model of metabolic syndrome via the inhibition of NF-kappaB activation.

Science.gov (United States)

Tan, Hong-wei; Xing, Shan-shan; Bi, Xiu-ping; Li, Li; Gong, Hui-ping; Zhong, Ming; Zhang, Yun; Zhang, Wei

2008-09-01

Metabolic syndrome is associated with an increased incidence of atherosclerosis. Clinical studies have shown that calcium channel blockers (CCB) inhibit the progression of atherosclerosis. However, the underlying mechanism is unclear. We investigated the inhibitory effect of felodipine on adhesion molecular expression and macrophage infiltration in the aorta of high fructose-fed rats (FFR). Male Wistar rats were given 10% fructose in drinking water. After 32 weeks of high fructose feeding, they were treated with felodipine (5 mg x kg(-1) x d(-1)) for 6 weeks. The control rats were given a normal diet and water. The aortic expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and the infiltration of macrophages were measured by real-time RT-PCR and/or immunohistochemistry. NF-kappaB activity was measured by electrophoretic mobility shift assay (EMSA). After 32 weeks of high fructose feeding, FFR displayed increased body weight, systolic blood pressure (SBP), serum insulin, and triglycerides when compared with the control rats. The aortic expressions of ICAM-1 and VCAM-1 were significantly increased in FFR than in the control rats and accompanied by the increased activity of NF-kappaB. FFR also showed significantly increased CD68- positive macrophages in the aortic wall. After treatment with felodipine, SBP, serum insulin, and the homeostasis model assessment decreased significantly. In addition to reducing ICAM-1 and VCAM-1, felodipine decreased macrophages in the aortic wall. EMSA revealed that felodipine inhibited NF-kappaB activation in FFR. Felodipine inhibited vessel wall inflammation. The inhibition of NF-kappaB may be involved in the modulation of vascular inflammatory response by CCB in metabolic syndrome.

Cues for cellular assembly of vascular elastin networks

Science.gov (United States)

Kothapalli, Chandrasekhar R.

LOX protein synthesis (2.5-fold); these cues also enhanced deposition of mature elastic fibers (˜1 mum diameter) within these cultures. Interestingly, instead of copper salt addition, even release of Cu 2+ ions (˜0.1 M) from copper nanoparticles (400 ng/mL), concurrent with HA oligomers, promoted crosslinking of elastin into mature matrix, with multiple bundles of highly-crosslinked elastin fiber formation observed (diameter ˜200-500 nm). These results strongly attest to the potential individual and combined benefits of these cues to faithful elastin matrix regeneration by healthy, patient-derived cells within tissue-engineered vascular constructs. When these cues (TGF-beta1 and HA oligomers) were added to TNF-alpha-stimulated SMC cultures, model cell culture systems mimicking phenotypically-altered cells within aneurysms, they upregulated elastin matrix production, organized elastin protein into fibers, and simultaneously stabilized this matrix by attenuating production of elastolytic enzymes. Similarly these cues also attenuated inflammatory cytokines release within cells isolated from induced-aortic aneurysms in rats, and significantly upregulated elastin synthesis and matrix formation by upregulating LOX and desmosine protein amounts. The cues were also highly effective in organizing the elastin into fibrous matrix structures mimicking the native elastin deposition process. The outcomes of this study might be of tremendous use in optimizing design of HA constructs to modulate vascular healing and matrix synthesis following revascularization, and in enabling repair of elastin networks within diseased or inflammatory (aneurysmal) adult vascular tissues.

Tuning differentiation signals for efficient propagation and in vitro validation of rat embryonic stem cell cultures.

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Meek, Stephen; Sutherland, Linda; Burdon, Tom

2015-01-01

The rat is one of the most commonly used laboratory animals in biomedical research and the recent isolation of genuine pluripotent rat embryonic stem (ES) cell lines has provided new opportunities for applying contemporary genetic engineering techniques to the rat and enhancing the use of this rodent in scientific research. Technical refinements that improve the stability of the rat ES cell cultures will undoubtedly further strengthen and broaden the use of these stem cells in biomedical research. Here, we describe a relatively simple and robust protocol that supports the propagation of germ line competent rat ES cells, and outline how tuning stem cell signaling using small molecule inhibitors can be used to both stabilize self-renewal of rat ES cell cultures and aid evaluation of their differentiation potential in vitro.

Promotion of Vascular Morphogenesis of Endothelial Cells Co-Cultured with Human Adipose-Derived Mesenchymal Stem Cells Using Polycaprolactone/Gelatin Nanofibrous Scaffolds

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Yun-Min Kook

2018-02-01

Full Text Available New blood vessel formation is essential for tissue regeneration to deliver oxygen and nutrients and to maintain tissue metabolism. In the field of tissue engineering, in vitro fabrication of new artificial vessels has been a longstanding challenge. Here we developed a technique to reconstruct a microvascular system using a polycaprolactone (PCL/gelatin nanofibrous structure and a co-culture system. Using a simple electrospinning process, we fabricated three-dimensional mesh scaffolds to support the sprouting of human umbilical vein endothelial cells (HUVECs along the electrospun nanofiber. The co-culture with adipose-derived mesenchymal stem cells (ADSCs supported greater sprouting of endothelial cells (ECs. In a two-dimensional culture system, angiogenic cell assembly produced more effective direct intercellular interactions and paracrine signaling from ADSCs to assist in the vascular formation of ECs, compared to the influence of growth factor. Although vascular endothelial growth factor and sphingosine-1-phosphate were present during the culture period, the presence of ADSCs was the most important factor for the construction of a cell-assembled structure in the two-dimensional culture system. On the contrary, HUVECs co-cultured on PCL/gelatin nanofiber scaffolds produced mature and functional microvessel and luminal structures with a greater expression of vascular markers, including platelet endothelial cell adhesion molecule-1 and podocalyxin. Furthermore, both angiogenic factors and cellular interactions with ADSCs through direct contact and paracrine molecules contributed to the formation of enhanced engineered blood vessel structures. It is expected that the co-culture system of HUVECs and ADSCs on bioengineered PCL/gelatin nanofibrous scaffolds will promote robust and functional microvessel structures and will be valuable for the regeneration of tissue with restored blood vessels.

RNA synthesis in primary cultures of adult rat hepatocytes

International Nuclear Information System (INIS)

Fugassa, E.; Gallo, G.; Voci, A.; Cordone, A.

1983-01-01

The ability of hepatocyte monolayers to synthesize RNA was investigated by measuring [3H]orotic acid incorporation into RNA and the total nuclear RNA polymerase activity as a function of the time in culture. The results demonstrate that primary cultures of hepatocytes maintained in a chemically defined serum- and hormone-free medium are able to synthesize RNA actively. This ability increases within the first 2 d of culture, despite the concomitant decrease in [3H]orotic acid uptake, and decreases only after 3 d. Factors such as serum, insulin, and dexamethasone, known to improve maintenance of functional hepatocytes, markedly stimulate the uptake of labeled precursor without apparently affecting the rate of RNA synthesis by cultured cells. It is suggested that the culture of adult rat hepatocytes provides a useful experimental model for the studies of hormonal regulation of transcription in liver

Comparison of mesencephalic free-floating tissue culture grafts and cell suspension grafts in the 6-hydroxydopamine-lesioned rat

DEFF Research Database (Denmark)

Meyer, Morten; Widmer, H R; Wagner, B

1998-01-01

days in culture or directly as dissociated cell suspensions, and compared with regard to neuronal survival and ability to normalize rotational behavior in adult rats with unilateral 6-hydroxydopamine (6-OHDA) lesions. Other lesioned rats received injections of cell-free medium and served as controls...... of grafted dopaminergic neurons and to correlate that with the behavioral effects. Additional cultures and acutely prepared explants were also fixed and stored for histological investigation in order to estimate the loss of dopaminergic neurons in culture and after transplantation. Similar behavioral...... improvements in terms of significant reductions in amphetamine-induced rotations were observed in rats grafted with FFRT cultures (127%) and rats grafted with cell suspensions (122%), while control animals showed no normalization of rotational behavior. At 84 days after transplantation, there were similar...

Biofabrication enables efficient interrogation and optimization of sequential culture of endothelial cells, fibroblasts and cardiomyocytes for formation of vascular cords in cardiac tissue engineering

International Nuclear Information System (INIS)

Iyer, Rohin K; Radisic, Milica; Chiu, Loraine L Y; Vunjak-Novakovic, Gordana

2012-01-01

We previously reported that preculture of fibroblasts (FBs) and endothelial cells (ECs) prior to cardiomyocytes (CMs) improved the structural and functional properties of engineered cardiac tissue compared to culture of CMs alone or co-culture of all three cell types. However, these approaches did not result in formation of capillary-like cords, which are precursors to vascularization in vivo. Here we hypothesized that seeding the ECs first on Matrigel and then FBs 24 h later to stabilize the endothelial network (sequential preculture) would enhance cord formation in engineered cardiac organoids. Three sequential preculture groups were tested by seeding ECs (D4T line) at 8%, 15% and 31% of the total cell number on Matrigel-coated microchannels and incubating for 24 h. Cardiac FBs were then seeded (32%, 25% and 9% of the total cell number, respectively) and incubated an additional 24 h. Finally, neonatal rat CMs (60% of the total cell number) were added and the organoids were cultivated for seven days. Within 24 h, the 8% EC group formed elongated cords which eventually developed into beating cylindrical organoids, while the 15% and 31% EC groups proliferated into flat EC monolayers with poor viability. Excitation threshold (ET) in the 8% EC group (3.4 ± 1.2 V cm −1 ) was comparable to that of the CM group (3.3 ± 1.4 V cm −1 ). The ET worsened with increasing EC seeding density (15% EC: 4.4 ± 1.5 V cm −1 ; 31% EC: 4.9 ± 1.5 V cm −1 ). Thus, sequential preculture promoted vascular cord formation and enhanced architecture and function of engineered heart tissues. (paper)

Edaravone injection reverses learning and memory deficits in a rat model of vascular dementia.

Science.gov (United States)

Li, Xu; Lu, Fen; Li, Wei; Qin, Lingzhi; Yao, Yong; Ge, Xuerong; Yu, Qingkai; Liang, Xinliang; Zhao, Dongmei; Li, Xiaohong; Zhang, Jiewen

2017-01-01

Edaravone is a novel free radical scavenger that exerts neuroprotective effects by inhibiting endothelial injury and by ameliorating neuronal damage in brain ischemia. Recently, it was reported that edaravone could alleviate the pathology and cognitive deficits of Alzheimer's disease patients. However, its relevance to vascular dementia (VaD) is not clear. In this study, we partially occluded the bilateral carotid arteries of rats surgically to induce chronic cerebral hypoperfusion (CCH), a well-known rat model of VaD. Water maze and step-down inhibitory test were used to evaluate the memory deficit. The activities of superoxide dismutase (SOD) and lactate dehydrogenase (LDH), the content of malondialdehyde (MDA) and total reactive oxygen species were measured to evaluate the oxidative stress level. Western blot analysis was used to evaluate the synaptic protein expression. It was found that treatment with edaravone for a 5-week period was able to reverse both spatial and fear-memory deficits in rats with CCH. Edaravone significantly reduced the level of oxidative stress in the brains of rats with CCH by increasing SOD activity and decreasing the content of MDA, LDH, and total reactive oxygen species. Furthermore, edaravone treatment also restored the levels of multiple synaptic proteins in the hippocampi of rats with CCH. Our data provide direct evidence supporting the neuroprotective effects of edaravone in VaD. We propose that the alleviation of oxidative stress and restoration of synaptic proteins play important roles in neuroprotection. © The Author 2016. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Musculus gastrocnemius tetanus kinetics in alcohol-intoxicated rats with experimentally-induced hindlimb vascular ischemia under conditions of low-frequence muscle fatigue

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O. A. Melnychuk

2014-04-01

Full Text Available Alcohol intoxication and ischemic injury of skeletal muscles often accompany each other. It is shown that patients hospitalized with chronic alcoholism develop muscle fatigue. Skeletal muscle dysfunction in alcohol-dependent patients is caused by ethanol-associated myofibrillar atrophy and metabolic disbalance, while compression-ischemic lesions result from unconsciousness of the patient, in case of taking the critical alcohol dose. Therefore, the aim of this study is to discover typical m. gastrocnemius (cap. med. tetanic kinetics changes in alcohol intoxicated rats with experimentally induced vascular ischemia of hindlimb muscles under conditions of low-frequency progressive muscle fatigue. Experiments were carried out on 10 young male Wistar rats (149.5 ± 5.8 g kept under standard vivarium conditions and diet. The investigation was conducted in two phases: chronic (30 days and acute (3 hours experiment. All surgical procedures were carried out aseptically under general anesthesia. Ishemic m. gastrocnemius (cap. med. tetanic kinetic changes and force productivity in alcohol intoxicated rats were investigated in the isometric mode, with direct electrical stimulation. The fatigue of m. gastrocnemius (cap. med. was evaluated by three characteristic criteria: the first sag effect, the secondary force rise, the second sag effect. There have been 10 similar experiments: 5 series in each study group with 10 tetanic runs in each series. The highest amplitude of the native m. gastrocnemius (cap. med. tetanus relative to isoline was taken as 100% force response. The same pattern of m. gastrocnemius (cap. med. low-frequency fatigue development was found in both rat groups under study. It is evidenced by the absence of substantial m. gastrocnemius (cap. med. tetanus kinetics differences in alcohol intoxicated rats, compared with non-alcohol intoxicated rats during fatigue test. However, the appreciable m. gastrocnemius (cap. med. tetanic force reduction

A procedure for culturing rat neocortex explants in a serum-free nutrient medium

NARCIS (Netherlands)

Romijn, H. J.; de Jong, B. M.; Ruijter, J. M.

1988-01-01

A procedure is described for long-term culturing of rat neocortex explants in a serum-free growth medium. Slices spanning the entire cortical depth from pial to ventricular side are prepared from 6-day-old rat pups. After preincubation in Hanks' balanced salt solution with extra glucose, the

Pre-diabetes augments neuropeptide Y1- and α1-receptor control of basal hindlimb vascular tone in young ZDF rats.

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Nicole M Novielli

Full Text Available Peripheral vascular disease in pre-diabetes may involve altered sympathetically-mediated vascular control. Thus, we investigated if pre-diabetes modifies baseline sympathetic Y(1-receptor (Y(1R and α(1-receptor (α(1R control of hindlimb blood flow (Q(fem and vascular conductance (VC.Q(fem and VC were measured in pre-diabetic ZDF rats (PD and lean controls (CTRL under infusion of BIBP3226 (Y(1R antagonist, prazosin (α(1R antagonist and BIBP3226+prazosin. Neuropeptide Y (NPY concentration and Y(1R and α(1R expression were determined from hindlimb skeletal muscle samples.Baseline Q(fem and VC were similar between groups. Independent infusions of BIBP3226 and prazosin led to increases in Q(fem and VC in CTRL and PD, where responses were greater in PD (p<0.05. The percent change in VC following both drugs was also greater in PD compared to CTRL (p<0.05. As well, Q(fem and VC responses to combined blockade (BIBP3226+prazosin were greater in PD compared to CTRL (p<0.05. Interestingly, an absence of synergistic effects was observed within groups, as the sum of the VC responses to independent drug infusions was similar to responses following combined blockade. Finally, white and red vastus skeletal muscle NPY concentration, Y(1R expression and α(1R expression were greater in PD compared to CTRL.For the first time, we report heightened baseline Y(1R and α(1R sympathetic control of Q(fem and VC in pre-diabetic ZDF rats. In support, our data suggest that augmented sympathetic ligand and receptor expression in pre-diabetes may contribute to vascular dysregulation.

Cell lineage in vascularized bone transplantation.

Science.gov (United States)

Willems, Wouter F; Larsen, Mikko; Friedrich, Patricia F; Bishop, Allen T

2014-01-01

The biology behind vascularized bone allotransplantation remains largely unknown. We aim to study cell traffic between donor and recipient following bone auto-, and allografting. Vascularized femoral transplantation was performed with arteriovenous bundle implantation and short-term immunosuppression. Twenty male Piebald Virol Glaxo (PVG; RT1(c) ) rats received isotransplants from female PVG (RT1(c) ) rats and 22 male PVG rats received allografts from female Dark Agouti rats (DA, RT1(a) ), representing a major histocompatibility mismatch. Both groups were randomly analyzed at 4 or 18 weeks. Bone remodeling areas (inner and outer cortical samples) were labeled and laser capture microdissected. Analysis of sex-mismatch genes by real-time reverse transcription-polymerase chain reaction provided the relative Expression Ratio (rER) of donor (female) to recipient (male) cells. The rER was 0.456 ± 0.266 at 4 weeks and 0.749 ± 0.387 at 18 weeks (p = 0.09) in allotransplants. In isotransplants, the rER was 0.412 ± 0.239 and 0.467 ± 0.252 at 4 and 18 weeks, respectively (p = 0.21). At 4 weeks, the rER at the outer cortical area of isotransplants was significantly lower in isotransplants as compared with allotransplants (0.247 ± 0.181 vs. 0.549 ± 0.184, p = 0.007). Cells in the inner and outer cortical bone remodeling areas in isotransplants were mainly donor derived (rER 0.5) at 18 weeks. Applying novel methodology, we describe detailed cell traffic in vascularized bone transplants, elaborating our comprehension on bone transplantation. Copyright © 2013 Wiley Periodicals, Inc.

The role of vascular protein and renin in chronic two-kidney, one clip Goldblatt hypertension

International Nuclear Information System (INIS)

Nakada, T.; Yamori, Y.

1982-01-01

Chronic hypertension was induced in rats by application of a clip for 17 or 20 weeks to the unilateral renal artery and leaving the contrarenal vessel intact. Some of the rats received antihypertensive treatment with phenoxybenzamine (POB). 3 H-proline was injected into all rats in the 17th experimental week to observe the in vivo incorporation rates of 3 H-proline into vascular non-collagenous protein and vascular collagen. Plasma renin activity (PRA) of decapitated rats was assayed in the terminal stage of the experiment. Significant differences were noted between 2K-1C hypertensive rats and sham-operated normotensive rats, the former rats having significantly higher incorporation rates of 3 H-proline into non-collagenous protein and collagen of testicular or mesenteric artery. These results indicate that increased synthesis of vascular non-collagenous protein as well as collagen, especially of small arteries, plays a major role for the pathogenesis of chronic hypertension in 2K-1C rats, and renin does not contribute to elevation of the blood pressure in the maintenance phase of this type of experimental hypertension

Antitumor Activity of Rat Mesenchymal Stem Cells during Direct or Indirect Co-Culturing with C6 Glioma Cells.

Science.gov (United States)

Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Mel'nikov, P A; Cherepanov, S A; Levinsky, A B; Chehonin, V P

2016-02-01

The tumor-suppressive effect of rat mesenchymal stem cells against low-differentiated rat C6 glioma cells during their direct and indirect co-culturing and during culturing of C6 glioma cells in the medium conditioned by mesenchymal stem cells was studied in an in vitro experiment. The most pronounced antitumor activity of mesenchymal stem cells was observed during direct co-culturing with C6 glioma cells. The number of live C6 glioma cells during indirect co-culturing and during culturing in conditioned medium was slightly higher than during direct co-culturing, but significantly differed from the control (C6 glioma cells cultured in medium conditioned by C6 glioma cells). The cytotoxic effect of medium conditioned by mesenchymal stem cells was not related to medium depletion by glioma cells during their growth. The medium conditioned by other "non-stem" cells (rat astrocytes and fibroblasts) produced no tumor-suppressive effect. Rat mesenchymal stem cells, similar to rat C6 glioma cells express connexin 43, the main astroglial gap junction protein. During co-culturing, mesenchymal stem cells and glioma C6 cells formed functionally active gap junctions. Gap junction blockade with connexon inhibitor carbenoxolone attenuated the antitumor effect observed during direct co-culturing of C6 glioma cells and mesenchymal stem cells to the level produced by conditioned medium. Cell-cell signaling mediated by gap junctions can be a mechanism of the tumor-suppressive effect of mesenchymal stem cells against C6 glioma cells. This phenomenon can be used for the development of new methods of cell therapy for high-grade malignant gliomas.

Effect of D-valine and cytosine arabinoside on [3H]thymidine incorporation in rat and rabbit epididymal epithelial cell cultures

International Nuclear Information System (INIS)

Orgebin-Crist, M.C.; Jonas-Davies, J.; Storey, P.; Olson, G.E.

1984-01-01

Epithelial cell enriched primary cultures were established from the rat and the rabbit epididymis. Epithelial cell aggregates, obtained after pronase digestion of minced epididymis, attached to the culture dish and after 72 h in vitro spread out to form discrete patches of cells. These cells have an epithelioid morphology and form a monolayer of closely apposed polygonal cells where DNA synthesis, as judged by [ 3 H]thymidine uptake, is very low. In L-valine medium the nonepithelial cell contamination was no more than 10% in rat and rabbit epididymal primary cultures. The labeling index of rat epididymal cells cultured in D-valine medium was significantly lower than that of cells cultured in L-valine medium. In contrast, the labeling index of rabbit epididymal cells cultured in D-valine medium was significantly higher than that of cells cultured in L-valine medium. Cytosine arabinoside decreased the number of labeled cells in both L-valine and D-valine cultures. From these results, it appears that D-valine is a selective agent for rat epididymal epithelial cells, but not for rabbit epithelial cells, and that cytosine arabinoside is a simple and effective means to control the proliferation of fibroblast-like cells in both rat and rabbit epididymal cell cultures

A new iridoid and effect on the rat aortic vascular smooth muscle cell proliferation of isolated compounds from Buddleja officinalis.

Science.gov (United States)

Tai, Bui Huu; Nhiem, Nguyen Xuan; Quang, Tran Hong; Ngan, Nguyen Thi Thanh; Tung, Nguyen Huu; Kim, Yohan; Lee, Jung-Jin; Myung, Chang-Seon; Cuong, Nguyen Manh; Kim, Young Ho

2011-06-01

A new iridoid, named methylscutelloside (1) together with 19 known compounds belonging to the iridoids (2-4), monoterpenoids (5), flavonoids (6-8), triterpenoids (9-14), and phenylethanoids (15-20) were isolated from the flowers of Buddleja officinalis. Their chemical structures were elucidated on the basis of physicochemical properties, and by spectroscopic methods including 1D, 2D NMR, and MS. All isolated compounds were tested in vitro for their effects on the proliferation of rat aortic vascular smooth muscle cells (VSMCs). Among them, iridoids were the main active components and showed significant inhibitory effects on PDGF-BB-induced proliferation in rat aortic VSMCs. Copyright © 2011 Elsevier Ltd. All rights reserved.

Advanced Glycation End-Products Induce Apoptosis of Vascular Smooth Muscle Cells: A Mechanism for Vascular Calcification

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Sayo Koike

2016-09-01

Full Text Available Vascular calcification, especially medial artery calcification, is associated with cardiovascular death in patients with diabetes mellitus and chronic kidney disease (CKD. To determine the underlying mechanism of vascular calcification, we have demonstrated in our previous report that advanced glycation end-products (AGEs stimulated calcium deposition in vascular smooth muscle cells (VSMCs through excessive oxidative stress and phenotypic transition into osteoblastic cells. Since AGEs can induce apoptosis, in this study we investigated its role on VSMC apoptosis, focusing mainly on the underlying mechanisms. A rat VSMC line (A7r5 was cultured, and treated with glycolaldehyde-derived AGE-bovine serum albumin (AGE3-BSA. Apoptotic cells were identified by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL staining. To quantify apoptosis, an enzyme-linked immunosorbent assay (ELISA for histone-complexed DNA fragments was employed. Real-time PCR was performed to determine the mRNA levels. Treatment of A7r5 cells with AGE3-BSA from 100 µg/mL concentration markedly increased apoptosis, which was suppressed by Nox inhibitors. AGE3-BSA significantly increased the mRNA expression of NAD(PH oxidase components including Nox4 and p22phox, and these findings were confirmed by protein levels using immunofluorescence. Dihydroethidisum assay showed that compared with cBSA, AGE3-BSA increased reactive oxygen species level in A7r5 cells. Furthermore, AGE3-induced apoptosis was significantly inhibited by siRNA-mediated knockdown of Nox4 or p22phox. Double knockdown of Nox4 and p22phox showed a similar inhibitory effect on apoptosis as single gene silencing. Thus, our results demonstrated that NAD(PH oxidase-derived oxidative stress are involved in AGEs-induced apoptosis of VSMCs. These findings might be important to understand the pathogenesis of vascular calcification in diabetes and CKD.

Radiation-induced PKC signaling system in cultured rat hepatocytes

International Nuclear Information System (INIS)

Nakajima, Tetsuo; Yukawa, Osami

1998-01-01

Radiation effects on living organisms are mainly caused through reactive oxygen species (ROS) on living cells. It is known that ROS damages various membranes and the bio membranes play an important role in cellular signal transduction pathways. The effects of radiation on cellular signal transduction pathways in cultured rat hepatocytes have been studied

Vascular and renal function in experimental thyroid disorders.

Science.gov (United States)

Vargas, Félix; Moreno, Juan Manuel; Rodríguez-Gómez, Isabel; Wangensteen, Rosemary; Osuna, Antonio; Alvarez-Guerra, Miriam; García-Estañ, Joaquín

2006-02-01

This review focuses on the effects of thyroid hormones in vascular and renal systems. Special emphasis is given to the mechanisms by which thyroid hormones affect the regulation of body fluids, vascular resistance and, ultimately, blood pressure. Vascular function is markedly affected by thyroid hormones that produce changes in vascular reactivity and endothelial function in hyper- and hypothyroidism. The hypothyroid state is accompanied by a marked decrease in sensitivity to vasoconstrictors, especially to sympathetic agonists, alteration that may play a role in the reduced blood pressure of hypothyroid rats, as well as in the preventive effects of hypothyroidism on experimental hypertension. Moreover, in hypothyroid rats, the endothelium-dependent and nitric oxide donors vasodilation is reduced. Conversely, the vessels from hyperthyroid rats showed an increased endothelium-dependent responsiveness that may be secondary to the shear-stress induced by the hyperdynamic circulation, and that may contribute to the reduced vascular resistance characteristic of this disease. Thyroid hormones also have important effects in the kidney, affecting renal growth, renal haemodynamics, and salt and water metabolism. In hyperthyroidism, there is a resetting of the pressure-natriuresis relationship related to hyperactivity of the renin-angiotensin system, which contributes to the arterial hypertension associated with this endocrine disease. Moreover, thyroid hormones affect the development and/or maintenance of various forms of arterial hypertension. This review also describes recent advances in our understanding of thyroid hormone action on nitric oxide and oxidative stress in the regulation of cardiovascular and renal function and in the long-term control of blood pressure.

Calcium channel blockers, more than diuretics, enhance vascular protective effects of angiotensin receptor blockers in salt-loaded hypertensive rats.

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Eiichiro Yamamoto

Full Text Available The combination therapy of an angiotensin receptor blocker (ARB with a calcium channel blocker (CCB or with a diuretic is favorably recommended for the treatment of hypertension. However, the difference between these two combination therapies is unclear. The present work was undertaken to examine the possible difference between the two combination therapies in vascular protection. Salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP were divided into 6 groups, and they were orally administered (1 vehicle, (2 olmesartan, an ARB, (3 azelnidipine, a CCB, (4 hydrochlorothiazide, a diuretic, (5 olmesartan combined with azelnidipine, or (6 olmesartan combined with hydrochlorothiazide. Olmesartan combined with either azelnidipine or hydrochlorothiazide ameliorated vascular endothelial dysfunction and remodeling in SHRSP more than did monotherapy with either agent. However, despite a comparable blood pressure lowering effect between the two treatments, azelnidipine enhanced the amelioration of vascular endothelial dysfunction and remodeling by olmesartan to a greater extent than did hydrochlorothiazide in salt-loaded SHRSP. The increased enhancement by azelnidipine of olmesartan-induced vascular protection than by hydrochlorothiazide was associated with a greater amelioration of vascular nicotinamide adenine dinucleotide phosphate (NADPH oxidase activation, superoxide, mitogen-activated protein kinase activation, and with a greater activation of the Akt/endothelial nitric oxide synthase (eNOS pathway. These results provided the first evidence that a CCB potentiates the vascular protective effects of an ARB in salt-sensitive hypertension, compared with a diuretic, and provided a novel rationale explaining the benefit of the combination therapy with an ARB and a CCB.

Methylmercury Causes Blood-Brain Barrier Damage in Rats via Upregulation of Vascular Endothelial Growth Factor Expression.

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Tetsuya Takahashi

Full Text Available Clinical manifestations of methylmercury (MeHg intoxication include cerebellar ataxia, concentric constriction of visual fields, and sensory and auditory disturbances. The symptoms depend on the site of MeHg damage, such as the cerebellum and occipital lobes. However, the underlying mechanism of MeHg-induced tissue vulnerability remains to be elucidated. In the present study, we used a rat model of subacute MeHg intoxication to investigate possible MeHg-induced blood-brain barrier (BBB damage. The model was established by exposing the rats to 20-ppm MeHg for up to 4 weeks; the rats exhibited severe cerebellar pathological changes, although there were no significant differences in mercury content among the different brain regions. BBB damage in the cerebellum after MeHg exposure was confirmed based on extravasation of endogenous immunoglobulin G (IgG and decreased expression of rat endothelial cell antigen-1. Furthermore, expression of vascular endothelial growth factor (VEGF, a potent angiogenic growth factor, increased markedly in the cerebellum and mildly in the occipital lobe following MeHg exposure. VEGF expression was detected mainly in astrocytes of the BBB. Intravenous administration of anti-VEGF neutralizing antibody mildly reduced the rate of hind-limb crossing signs observed in MeHg-exposed rats. In conclusion, we demonstrated for the first time that MeHg induces BBB damage via upregulation of VEGF expression at the BBB in vivo. Further studies are required in order to determine whether treatment targeted at VEGF can ameliorate MeHg-induced toxicity.

Novel microspheres reduce the formation of deep venous thrombosis and repair the vascular wall in a rat model.

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Dai, Bingyang; Li, Lan; Li, Qiangqiang; Song, Xiaoxiao; Chen, Dongyang; Dai, Jin; Yao, Yao; Yan, Wenjin; Teng, Huajian; Yang, Fang; Xu, Zhihong; Jiang, Qing

2017-07-01

: L-Arginine (L-arg), widely known as a substrate for endogenous nitric oxide synthesis, can improve endothelial function associated with the vasculature, inhibit platelet aggregation, and alter the activity of vascular smooth muscle cells. P-selectin is a membrane component of the platelet alpha-granule and the endothelial cell-specific Wiebel-Palade body that plays a central role in mediating interactions between platelets and both leukocytes and the endothelium. The experiment was designed to evaluate the effect of novel microspheres with L-arg targeting P-selectin on the formation of deep vein thrombosis and repair of vascular wall in a rat model. Thrombosis of the inferior vena cava was induced by applying a piece of filter paper (5 mm × 10 mm) saturated with 10% FeCl3 solution for 5 min. Targeted microspheres with L-arg, targeted microspheres with water, and saline were injected into the tail veins of the rats after 30 min of applying the filter paper saturated with 10% FeCl3 solution. The dry weight and length of the thrombus isolated from the inferior vena cava were significantly decreased in the group with L-arg in microsphere after 24 h. No significant differences in prothrombin time, activated partial thromboplastin time, thrombin time, and fibrinogen among the groups were indicated. Images revealed that apoptosis in the vascular wall was less in the group injected with targeted microspheres with L-arg than in the other two groups at 1 and 8 d postsurgery. Meanwhile, cell proliferation was considerably excessive in the group injected with L-arg wrapped in targeted microspheres. Therefore, these novel microspheres could decrease the formation of thrombus in the early stages and in the subsequent periods of thrombosis. The microspheres can also enhance the vitality of impaired endothelial cells and reduce cell apoptosis.

[A study on the role of vascular endothelial growth factor in emphysema of rat caused by smog exposure].

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Chen, Jin-long; Ran, Pi-xin

2003-11-01

To explore the role of vascular endothelial growth factor (VEGF) in emphysema of rat caused by smog exposure. Thirty-six 12-week male rats were randomly divided into 2 groups: a smog exposure group (S group), and a normal control group (N group). S group rats were randomly subdivided into 3 groups: S(1) group, S(2) group, S(3) group, which were exposed to smog for 2 weeks, 4 weeks, 8 weeks, respectively; N group rats were randomly subdivided into 3 groups: N(1) group, N(2) group, N(3) group, which were raised in normal oxygen condition for 0 week, 4 weeks, 8 weeks, respectively. The expressions of VEGF mRNA and VEGF protein and kinase-insert domain containing receptor (KDR) protein were determined by reverse transcription-polymerase chain reaction (RT-PCR) and modified SABC immunohistochemistry assay separately. The pathological change in smog exposure rat lung was determined by HE staining. MLI and MAN were determined as an index of emphysema. Variance analysis, nonparametric analysis and correlate analysis were conducted in SPSS 10.0. (1) There were airway inflammation in S group rat lungs, and an early-emphysema-like change in S(3) group rat lungs: MAN in S(3) group was significantly decreased compared with N(3) group, MLI in S(3) group was significantly increased compared with N(3) group (P 0.05). (3) VEGF protein expression in alveolar epithelium and bronchial epithelium had a positive correlation with MAN (r = 0.43, r = 0.37, P Smog exposure decrease the expression of VEGF and KDR in rat lung. VEGF might involve in the pathology of emphysema caused by smog exposure.

The effects of local nitroglycerin on the surgical delay procedure in prefabricated flaps by vascular implant in rats.

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Sá, Jairo Zacchê de; Aguiar, José Lamartine de Andrade; Cruz, Adriana Ferreira; Schuler, Alexandre Ricardo Pereira; Lima, José Ricardo Alves de; Marques, Olga Martins

2012-12-01

To evaluate the effect of local nitroglycerin on the viable area of a prefabricated flap for vascular implant in rats, and to investigate the surgical delay procedure. A femoral pedicle was implanted under the skin of the abdominal wall in forty Wistar rats. The animals were divided into four groups of ten: group 1 - without surgical delay procedure and local nitroglycerin; group 2 - with surgical delay procedure, but without local nitroglycerin; group 3 - without surgical delay procedure, but with local nitroglycerin; and group 4 - with simultaneous surgical delay procedure and local nitroglycerin. The percentages of the viable areas, in relation to the total flap, were calculated using AutoCAD R 14. The mean percentage value of the viable area was 8.9% in the group 1. 49.4% in the group 2; 8.4% in the group 3 and 1.1% in the group 4. There was significant difference between groups 1 and 2 (p=0.005), 1 and 4 (p=0.024), 2 and 3 (p=0.003), 2 and 4 (p=0.001). These results support the hypothesis that the closure of the arterial venous channels is responsible for the phenomenon of surgical delay procedure. Local nitroglycerin did not cause an increase in the prefabricated viable flap area by vascular implantation and decreased the viable flap area that underwent delay procedures.

Vascular and neuronal protection induced by the ocular administration of nerve growth factor in diabetic-induced rat encephalopathy.

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Tirassa, Paola; Maccarone, Mattia; Florenzano, Fulvio; Cartolano, Sara; De Nicolò, Sara

2013-05-01

Based on our previous findings on the efficacy of ocular applied nerve growth factor as eye drops (oNGF) to act in brain and counteract neuronal damage, we hypothesized that oNGF treatment might revert neuronal atrophy occurring in diabetic brain also by controlling neurotrophin system changes. The major NGF brain target areas, such as the septum and the hippocampus, were used as an experimental paradigma to test this hypothesis. Bilateral oNGF treatment was performed twice a day for 2 weeks in full-blown streptozotocin-treated adult male rats. The forebrain distribution of cholinergic and endothelial cell markers and NGF receptors were studied by confocal microscopy. The septo-hippocampal content of NGF mature and precursor form and NGF receptors expression were also analyzed by Elisa and Western blot. oNGF treatment recovers the morphological alterations and the neuronal atrophy in septum and normalized the expression of mature and pro-NGF, as well as NGF receptors in the septum and hippocampus of diabetic rats. In addition, oNGF stimulated brain vascularization and up-regulated the TRKA receptor in vessel endothelium. Our findings confirm that reduced availability of mature NGF and NGF signaling impairment favors vascular and neuronal alterations in diabetic septo-hippocampal areas and corroborate the ability of oNGF to act as a neuroprotective agent in brain. © 2013 Blackwell Publishing Ltd.

Incorporation of a prolyl hydroxylase inhibitor into scaffolds: a strategy for stimulating vascularization.

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Sham, Adeline; Martinez, Eliana C; Beyer, Sebastian; Trau, Dieter W; Raghunath, Michael

2015-03-01

Clinical applications of tissue engineering are constrained by the ability of the implanted construct to invoke vascularization in adequate extent and velocity. To overcome the current limitations presented by local delivery of single angiogenic factors, we explored the incorporation of prolyl hydroxylase inhibitors (PHIs) into scaffolds as an alternative vascularization strategy. PHIs are small molecule drugs that can stabilize the alpha subunit of hypoxia-inducible factor-1 (HIF-1), a key transcription factor that regulates a variety of angiogenic mechanisms. In this study, we conjugated the PHI pyridine-2,4-dicarboxylic acid (PDCA) through amide bonds to a gelatin sponge (Gelfoam(®)). Fibroblasts cultured on PDCA-Gelfoam were able to infiltrate and proliferate in these scaffolds while secreting significantly more vascular endothelial growth factor than cells grown on Gelfoam without PDCA. Reporter cells expressing green fluorescent protein-tagged HIF-1α exhibited dose-dependent stabilization of this angiogenic transcription factor when growing within PDCA-Gelfoam constructs. Subsequently, we implanted PDCA-Gelfoam scaffolds into the perirenal fat tissue of Sprague Dawley rats for 8 days. Immunostaining of explants revealed that the PDCA-Gelfoam scaffolds were amply infiltrated by cells and promoted vascular ingrowth in a dose-dependent manner. Thus, the incorporation of PHIs into scaffolds appears to be a feasible strategy for improving vascularization in regenerative medicine applications.

Imaging separation of neuronal from vascular effects of cocaine on rat cortical brain in vivo

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Yuan, Z.; Du, C.; Luo, Z.; Volkow, N.D.; Pan, Y.

2011-01-01

MRI techniques to study brain function assume coupling between neuronal activity, metabolism and flow. However, recent evidence of physiological uncoupling between neuronal and cerebrovascular events highlights the need for methods to simultaneously measure these three properties. We report a multimodality optical approach that integrates dual-wavelength laser speckle imaging (measures changes in blood flow, blood volume and hemoglobin oxygenation), digital-frequency-ramping optical coherence tomography (images quantitative 3D vascular network) and Rhod2 fluorescence (images intracellular calcium for measure of neuronal activity) at high spatiotemporal resolutions (30 (micro)m, 10 Hz) and over a large field of view (3 x 5 mm 2 ). We apply it to assess cocaine's effects in rat cortical brain and show an immediate decrease 3.5 ± 0.9 min, phase (1) in the oxygen content of hemoglobin and the cerebral blood flow followed by an overshoot 7.1 ± 0.2 min, phase (2) lasting over 20 min whereas Ca 2+ increased immediately (peaked at t = 4.1 ± 0.4 min) and remained elevated. This enabled us to identify a delay (2.9 ± 0.5 min) between peak neuronal and vascular responses in phase 2. The ability of this multimodality optical approach for simultaneous imaging at high spatiotemporal resolutions permits us to distinguish the vascular versus cellular changes of the brain, thus complimenting other neuroimaging modalities for brain functional studies (e. g., PET, fMRI).

Imaging separation of neuronal from vascular effects of cocaine on rat cortical brain in vivo

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Yuan, Z.; Du, C.; Yuan, Z.; Luo, Z.; Volkow, N.D.; Pan, Y.; Du, C.

2010-09-08

MRI techniques to study brain function assume coupling between neuronal activity, metabolism and flow. However, recent evidence of physiological uncoupling between neuronal and cerebrovascular events highlights the need for methods to simultaneously measure these three properties. We report a multimodality optical approach that integrates dual-wavelength laser speckle imaging (measures changes in blood flow, blood volume and hemoglobin oxygenation), digital-frequency-ramping optical coherence tomography (images quantitative 3D vascular network) and Rhod2 fluorescence (images intracellular calcium for measure of neuronal activity) at high spatiotemporal resolutions (30 {micro}m, 10 Hz) and over a large field of view (3 x 5 mm{sup 2}). We apply it to assess cocaine's effects in rat cortical brain and show an immediate decrease 3.5 {+-} 0.9 min, phase (1) in the oxygen content of hemoglobin and the cerebral blood flow followed by an overshoot 7.1 {+-} 0.2 min, phase (2) lasting over 20 min whereas Ca{sup 2+} increased immediately (peaked at t = 4.1 {+-} 0.4 min) and remained elevated. This enabled us to identify a delay (2.9 {+-} 0.5 min) between peak neuronal and vascular responses in phase 2. The ability of this multimodality optical approach for simultaneous imaging at high spatiotemporal resolutions permits us to distinguish the vascular versus cellular changes of the brain, thus complimenting other neuroimaging modalities for brain functional studies (e. g., PET, fMRI).

Sida rhomboidea.Roxb aqueous extract down-regulates in vivo expression of vascular cell adhesion molecules in atherogenic rats and inhibits in vitro macrophage differentiation and foam cell formation.

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Thounaojam, Menaka C; Jadeja, Ravirajsinh N; Salunke, Sunita P; Devkar, Ranjitsinh V; Ramachandran, A V

2012-10-01

The present study evaluates efficacy of Sida rhomboidea.Roxb (SR) leaves extract in ameliorating experimental atherosclerosis using in vitro and in vivo experimental models. Atherogenic (ATH) diet fed rats recorded significant increment in the serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very LDL (VLDL), autoantibody against oxidized LDL (Ox-LDL), markers of LDL oxidation and decrement in high-density lipoprotein (HDL) along with increment in aortic TC and TG. The ex vivo LDL oxidation assay revealed an increased susceptibility of LDL isolated from ATH rats to undergo copper mediated oxidation. These set of changes were minimized by simultaneous co-supplementation of SR extract to ATH diet fed rats. Histopathology of aorta and immunolocalization studies recorded pronounced atheromatous plaque formation, vascular calcification, significant elastin derangements and higher expression of macrophage surface marker (F4/80), vascular cell adhesion molecule-1 (VCAM-1) and p-selectin in ATH rats. Whereas, ATH+SR rats depicted minimal evidence of atheromatous plaque formation, calcium deposition, distortion/defragmentation of elastin and accumulation of macrophages along with lowered expression of VCAM-1 and P-selectin compared to ATH rats. Further, monocyte to macrophage differentiation and in vitro foam cell formation were significantly attenuated in presence of SR extract. In conclusion, SR extract has the potency of controlling experimental atherosclerosis and can be used as promising herbal supplement in combating atherosclerosis.

Cell proliferation along vascular islands during microvascular network growth

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Kelly-Goss Molly R

2012-06-01

Full Text Available Abstract Background Observations in our laboratory provide evidence of vascular islands, defined as disconnected endothelial cell segments, in the adult microcirculation. The objective of this study was to determine if vascular islands are involved in angiogenesis during microvascular network growth. Results Mesenteric tissues, which allow visualization of entire microvascular networks at a single cell level, were harvested from unstimulated adult male Wistar rats and Wistar rats 3 and 10 days post angiogenesis stimulation by mast cell degranulation with compound 48/80. Tissues were immunolabeled for PECAM and BRDU. Identification of vessel lumens via injection of FITC-dextran confirmed that endothelial cell segments were disconnected from nearby patent networks. Stimulated networks displayed increases in vascular area, length density, and capillary sprouting. On day 3, the percentage of islands with at least one BRDU-positive cell increased compared to the unstimulated level and was equal to the percentage of capillary sprouts with at least one BRDU-positive cell. At day 10, the number of vascular islands per vascular area dramatically decreased compared to unstimulated and day 3 levels. Conclusions These results show that vascular islands have the ability to proliferate and suggest that they are able to incorporate into the microcirculation during the initial stages of microvascular network growth.

Vascularized bone transplant chimerism mediated by vascular endothelial growth factor.

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Willems, Wouter F; Larsen, Mikko; Friedrich, Patricia F; Bishop, Allen T

2015-01-01

Vascular endothelial growth factor (VEGF) induces angiogenesis and osteogenesis in bone allotransplants. We aim to determine whether bone remodeling in VEGF-treated bone allotransplants results from repopulation with circulation-derived autogenous cells or survival of allogenic transplant-derived cells. Vascularized femoral bone transplants were transplanted from female Dark Agouti rats (DA;RT1(a) ) to male Piebald Viral Glaxo (PVG;RT1(c) ). Arteriovenous bundle implantation and short-term immunosuppression were used to maintain cellular viability. VEGF was encapsulated in biodegradable microspheres and delivered intramedullary in the experimental group (n = 22). In the control group (n = 22), no VEGF was delivered. Rats were sacrificed at 4 or 18 weeks. Laser capture microdissection of bone remodeling areas was performed at the inner and outer cortex. Sex-mismatched genes were quantified with reverse transcription-polymerase chain reaction to determine the amount of male cells to total cells, defined as the relative expression ratio (rER). At 4 weeks, rER was significantly higher at the inner cortex in VEGF-treated transplants as compared to untreated transplants (0.622 ± 0.225 vs. 0.362 ± 0.081, P = 0.043). At 4 weeks, the outer cortex in the control group had a significantly higher rER (P = 0.038), whereas in the VEGF group, the inner cortex had a higher rER (P = 0.015). Over time, in the outer cortex the rER significantly increased to 0.634 ± 0.106 at 18 weeks in VEGF-treated rats (P = 0.049). At 18 weeks, the rER was >0.5 at all cortical areas in both groups. These in vivo findings suggest a chemotactic effect of intramedullary applied VEGF on recipient-derived bone and could imply that more rapid angiogenesis of vascularized allotransplants can be established with microencapsulated VEGF. © 2014 Wiley Periodicals, Inc.

Beneficial Effects of Different Flavonoids on Vascular and Renal Function in L-NAME Hypertensive Rats

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M. Dolores Paredes

2018-04-01

Full Text Available Background: we have evaluated the antihypertensive effect of several flavonoid extracts in a rat model of arterial hypertension caused by chronic administration (6 weeks of the nitric oxide synthesis inhibitor, L-NAME. Methods: Sprague Dawley rats received L-NAME alone or L-NAME plus flavonoid-rich vegetal extracts (Lemon, Grapefruit + Bitter Orange, and Cocoa or purified flavonoids (Apigenin and Diosmin for 6 weeks. Results: L-NAME treatment resulted in a marked elevation of blood pressure, and treatment with Apigenin, Lemon Extract, and Grapefruit + Bitter Orange extracts significantly reduced the elevated blood pressure of these animals. Apigenin and some of these flavonoids also ameliorated nitric oxide-dependent and -independent aortic vasodilation and elevated nitrite urinary excretion. End-organ abnormalities such as cardiac infarcts, hyaline arteriopathy and fibrinoid necrosis in coronary arteries and aorta were improved by these treatments, reducing the end-organ vascular damage. Conclusions: the flavonoids included in this study, specially apigenin, may be used as functional food ingredients with potential therapeutic benefit in arterial hypertension.

Blockade of vascular adhesion protein-1 inhibits lymphocyte infiltration in rat liver allograft rejection.

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Martelius, Timi; Salaspuro, Ville; Salmi, Marko; Krogerus, Leena; Höckerstedt, Krister; Jalkanen, Sirpa; Lautenschlager, Irmeli

2004-12-01

Vascular adhesion protein-1 (VAP-1) has been shown to mediate lymphocyte adhesion to endothelia at sites of inflammation, but its functional role in vivo has not been tested in any rodent model. Here we report the effects of VAP-1 blockade on rat liver allograft rejection. BN recipients of PVG liver allografts (known to develop acute rejection by day 7) were treated with 2 mg/kg anti-VAP-1 (a new anti-rat VAP-1 mAb 174-5) or isotype-matched irrelevant antibody (NS1) every other day (n = 6/group) and one group with anti-VAP-1 2 mg/kg daily (n = 7). On day 7, samples were collected for transplant aspiration cytology, histology, and immunohistochemistry. Lymphocyte infiltration to the graft was clearly affected by VAP-blockade. The total inflammation, mainly the number of active lymphoid cells, in transplant aspiration cytology was significantly decreased in animals treated with anti-VAP-1 (4.7 +/- 1.0 and 2.4 +/- 1.0 corrected increment units, respectively) compared to control (6.6 +/- 1.0) (P VAP-1 plays an important role in lymphocyte infiltration to sites of inflammation, and, in particular, liver allograft rejection.

Establishment of a vascular endothelial cell-reactive type II NKT cell clone from a rat model of autoimmune vasculitis.

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Iinuma, Chihiro; Waki, Masashi; Kawakami, Ai; Yamaguchi, Madoka; Tomaru, Utano; Sasaki, Naomi; Masuda, Sakiko; Matsui, Yuki; Iwasaki, Sari; Baba, Tomohisa; Kasahara, Masanori; Yoshiki, Takashi; Paletta, Daniel; Herrmann, Thomas; Ishizu, Akihiro

2015-02-01

We previously generated a rat model that spontaneously developed small vessel vasculitis (SVV). In this study, a T cell clone reactive with rat vascular endothelial cells (REC) was established and named VASC-1. Intravenous injection of VASC-1 induced SVV in normal recipients. VASC-1 was a TCRαβ/CD3-positive CD4/CD8 double-negative T cell clone with expression of NKG2D. The cytokine mRNA profile under unstimulated condition was positive for IL-4 and IFN-γ but negative for IL-2 and IL-10. After interaction with REC, the mRNA expression of IL-2, IL-5 and IL-6 was induced in VASC-1, which was inhibited by blocking of CD1d on the REC surface. Although the protein levels of these cytokines seemed to be lower than the detection limit in the culture medium, IFN-γ was detectable. The production of IFN-γ from the VASC-1 stimulated with LPS-pre-treated REC was inhibited by the CD1d blockade on the REC. These findings indicated VASC-1 as an NKT cell clone. The NKT cell pool includes two major subsets, namely types I and II. Type I NKT cells are characterized by expression of semi-invariant TCRs and the potential to bind to marine sponge-derived α-galactosylceramide (α-GalCer) loaded on CD1d; whereas, type II NKT cells do not manifest these characteristics. VASC-1 exhibited a usage of TCR other than the type I invariant TCR α chain and did not bind to α-GalCer-loaded CD1d; therefore, it was determined as a type II NKT cell clone. The collective evidence suggested that REC-reactive type II NKT cells could be involved in the pathogenesis of SVV in rats. © The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

4-Phenylbutyrate Benefits Traumatic Hemorrhagic Shock in Rats by Attenuating Oxidative Stress, Not by Attenuating Endoplasmic Reticulum Stress.

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Yang, Guangming; Peng, Xiaoyong; Hu, Yi; Lan, Dan; Wu, Yue; Li, Tao; Liu, Liangming

2016-07-01

Vascular dysfunction such as vascular hyporeactivity following severe trauma and shock is a major cause of death in injured patients. Oxidative stress and endoplasmic reticulum stress play an important role in vascular dysfunction. The objective of the present study was to determine whether or not 4-phenylbutyrate can improve vascular dysfunction and elicit antishock effects by inhibiting oxidative and endoplasmic reticulum stress. Prospective, randomized, controlled laboratory experiment. State key laboratory of trauma, burns, and combined injury. Five hundred and fifty-two Sprague-Dawley rats. Rats were anesthetized, and a model of traumatic hemorrhagic shock was established by left femur fracture and hemorrhage. The effects of 4-phenylbutyrate (5, 20, 50, 100, 200, and 300 mg/kg) on vascular reactivity, animal survival, hemodynamics, and vital organ function in traumatic hemorrhagic shock rats and cultured vascular smooth muscle cells, and the relationship to oxidative stress and endoplasmic reticulum stress was observed. Lower doses of 4-phenylbutyrate significantly improved the vascular function, stabilized the hemodynamics, and increased the tissue blood flow and vital organ function in traumatic hemorrhagic shock rats, and markedly improved the survival outcomes. Among all dosages observed in the present study, 20 mg/kg of 4-phenylbutyrate had the best effect. Further results indicated that 4-phenylbutyrate significantly inhibited the oxidative stress, decreased shock-induced oxidative stress index such as the production of reactive oxygen species, increased the antioxidant enzyme levels such as superoxide dismutase, catalase, and glutathione, and improved the mitochondrial function by inhibiting the opening of the mitochondrial permeability transition pore in rat artery and vascular smooth muscle cells. In contrast, 4-phenylbutyrate did not affect the changes of endoplasmic reticulum stress markers following traumatic hemorrhagic shock. Furthermore, 4

Control of fibronectin synthesis by rat granulosa cells in culture

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Skinner, M.K.; Dorrington, J.H.

1984-01-01

The secreted and cellular [ 35 S]methionine-radiolabeled proteins of cultured rat granulosa cells were separated by electrophoresis on sodium dodecylsulfate (SDS) polyacrylamide gradient slab gels. From 24 to 72 h of culture FSH increased the intensity of labeling of most of the secreted proteins. A 220,000-dalton protein, however, increased in intensity only in control cultures and became the major secreted protein after 72 h, comprising 20% of the total radiolabeled proteins. This protein was identified as fibronectin by immunoprecipitation. There was no increase in the secreted or cellular fibronectin in FSH- or testosterone- and insulin-treated cultures. These studies indicate that a component of extracellular matrix is a major secretory product of unstimulated immature granulosa cells. As hormones induce the differentiated functions of granulosa cells in culture, the secretion of fibronectin is inhibited

Royal Jelly Prevents Osteoporosis in Rats: Beneficial Effects in Ovariectomy Model and in Bone Tissue Culture Model

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Saburo Hidaka

2006-01-01

Full Text Available Royal jelly (RJ has been used worldwide for many years as medical products, health foods and cosmetics. Since RJ contains testosterone and has steroid hormone-type activities, we hypothesized that it may have beneficial effects on osteoporosis. We used both an ovariectomized rat model and a tissue culture model. Rats were divided into eight groups as follows: sham-operated (Sham, ovariectomized (OVX, OVX given 0.5% (w/w raw RJ, OVX given 2.0% (w/w RJ, OVX given 0.5% (w/w protease-treated RJ (pRJ, OVX given 2.0% (w/w pRJ, OVX given 17β-estradiol and OVX given its vehicle, respectively. The Ovariectomy decreased tibial bone mineral density (BMD by 24%. Administration of 17β-estradiol to OVX rats recovered the tibial BMD decrease by 100%. Administration of 2.0% (w/w RJ and 0.5–2.0% (w/w pRJ to OVX rats recovered it by 85% or more. These results indicate that both RJ and pRJ are almost as effective as 17β-estradiol in preventing the development of bone loss induced by ovariectomy in rats. In tissue culture models, both RJ and pRJ increased calcium contents in femoral-diaphyseal and femoral-metaphyseal tissue cultures obtained from normal male rats. However, in a mouse marrow culture model, they neither inhibited the parathyroid hormone (PTH-induced calcium loss nor affected the formation of osteoclast-like cells induced by PTH in mouse marrow culture system. Therefore, our results suggest that both RJ and pRJ may prevent osteoporosis by enhancing intestinal calcium absorption, but not by directly antagonizing the action of PTH.

KCl cotransport regulation and protein kinase G in cultured vascular smooth muscle cells.

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Adragna, N C; Zhang, J; Di Fulvio, M; Lincoln, T M; Lauf, P K

2002-05-15

K-Cl cotransport is activated by vasodilators in erythrocytes and vascular smooth muscle cells and its regulation involves putative kinase/phosphatase cascades. N-ethylmaleimide (NEM) activates the system presumably by inhibiting a protein kinase. Nitrovasodilators relax smooth muscle via cGMP-dependent activation of protein kinase G (PKG), a regulator of membrane channels and transporters. We investigated whether PKG regulates K-Cl cotransport activity or mRNA expression in normal, PKG-deficient-vector-only-transfected (PKG-) and PKG-catalytic-domain-transfected (PKG+) rat aortic smooth muscle cells. K-Cl cotransport was calculated as the Cl-dependent Rb influx, and mRNA was determined by semiquantitative RT-PCR. Baseline K-Cl cotransport was higher in PKG+ than in PKG- cells (p <0.01). At 0.5 mM, NEM stimulated K-Cl cotransport by 5-fold in PKG- but not in PKG+ cells. However, NEM was more potent although less effective to activate K-Cl cotransport in normal (passage 1-3) and PKG+ than in PKG- cells. In PKG- cells, [(dihydroindenyl) oxy] alkanoic acid (300 mM) but not furosemide (1 mM) inhibited K-Cl cotransport. Furthermore, no difference in K-Cl cotransport mRNA expression was observed between these cells. In conclusion, this study shows that manipulation of PKG expression in vascular smooth muscle cells affects K-Cl cotransport activity and its activation by NEM.

Differential effects of Rho-kinase inhibitor and angiotensin II type-1 receptor antagonist on the vascular function in hypertensive rats induced by chronic l-NAME treatment

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Bainian Chen

2012-10-01

Full Text Available Little attention has been paid to the effect of Rho-kinase inhibitor on the vascular dysfunction of nitric oxide-deficient hypertension. We aimed to investigate whether the Rho-kinase inhibitor fasudil showed beneficial effect on the vascular dysfunction of the NG-nitro-l-arginine methyl ester (l-NAME treated rat, as well as to compare the differential effects of fasudil and angiotensin II receptor antagonist valsartan on vascular function. In the present study, both valsartan and fasudil exerted antihypertensive action on the l-NAME-treated rats, while only valsartan attenuated the cardiac hypertrophy. Treatment with valsartan showed improvement on vascular reactivity to norepinephrine, KCl and CaCl2, whereas fasudil therapy showed little effect on vasoconstriction. Endothelium-dependent vasodilation to acetylcholine was reduced in the NO-deficient group but was normalized by the fasudil therapy. The increased expression of RhoA and Rho-kinase (ROCK in the vasculature was corrected well to normal level by either valsartan or fasudil administration, which seemed to be at least partially responsible for the beneficial effect of the drug infusion. These findings suggest that the angiotensin II receptor antagonist interferes more with the contractile response than Rho-kinase inhibitor, whereas inhibition of Rho-kinase activity exhibits a better improvement on vasorelaxation than blockade of angiotensin II receptor.

Na+K+-ATPase activity and K+ channels differently contribute to vascular relaxation in male and female rats.

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Fernanda Moura Vargas Dias

Full Text Available Gender associated differences in vascular reactivity regulation might contribute to the low incidence of cardiovascular disease in women. Cardiovascular protection is suggested to depend on female sex hormones' effects on endothelial function and vascular tone regulation. We tested the hypothesis that potassium (K+ channels and Na+K+-ATPase may be involved in the gender-based vascular reactivity differences. Aortic rings from female and male rats were used to examine the involvement of K+ channels and Na+K+-ATPase in vascular reactivity. Acetylcholine (ACh-induced relaxation was analyzed in the presence of L-NAME (100 µM and the following K+ channels blockers: tetraethylammonium (TEA, 2 mM, 4-aminopyridine (4-AP, 5 mM, iberiotoxin (IbTX, 30 nM, apamin (0.5 µM and charybdotoxin (ChTX, 0.1 µM. The ACh-induced relaxation sensitivity was greater in the female group. After incubation with 4-AP the ACh-dependent relaxation was reduced in both groups. However, the dAUC was greater in males, suggesting that the voltage-dependent K+ channel (Kv participates more in males. Inhibition of the three types of Ca2+-activated K+ channels induced a greater reduction in Rmax in females than in males. The functional activity of the Na+K+-ATPase was evaluated by KCl-induced relaxation after L-NAME and OUA incubation. OUA reduced K+-induced relaxation in female and male groups, however, it was greater in males, suggesting a greater Na+K+-ATPase functional activity. L-NAME reduced K+-induced relaxation only in the female group, suggesting that nitric oxide (NO participates more in their functional Na+K+-ATPase activity. These results suggest that the K+ channels involved in the gender-based vascular relaxation differences are the large conductance Ca2+-activated K+ channels (BKCa in females and Kv in males and in the K+-induced relaxation and the Na+K+-ATPase vascular functional activity is greater in males.

Characterization of cutaneous vascular permeability induced by platelet-activating factor in guinea pigs and rats and its inhibition by a platelet-activating factor receptor antagonist

International Nuclear Information System (INIS)

Hwang, S.B.; Li, C.L.; Lam, M.H.; Shen, T.Y.

1985-01-01

Mechanisms of platelet-activating factor (PAF)-induced increases of cutaneous vascular permeability in guinea pigs and in rats were further explored. PAF so far is the most potent vasoactive mediator, being more than 1000-fold more potent than histamine and bradykinin in both species. In guinea pigs, there is a time delay of 5 to 10 minutes before PAF action, whereas, in the rat, the increased vasopermeability occurs immediately following the intradermal PAF injection. Relative vasoactive potencies of PAF and several structure-related analogues in both species correlate very well with their relative inhibition of the binding of 3 H-PAF to specific receptor sites on isolated rabbit platelet plasma membranes and their aggregatory abilities of rabbit platelets. Furthermore, the PAF-induced cutaneous vascular permeability is inhibitable by a competitive specific PAF receptor antagonist, kadsurenone, suggesting that binding of PAF to its specific receptor site is the first step to initiate its action of increased cutaneous vascular permeability. Several pure cyclooxygenase inhibitors, including indomethacin, diflunisal, and flurbiprofen, and the dual cyclooxygenase/lipoxygenase inhibitor, BW755C, but not the histamine antagonists, inhibit the PAF-induced vasopermeability in guinea pigs. The inhibition by indomethacin or BW755C can be fully reversed by coinjection intradermally with PAF and prostaglandin E1 but not leukotriene B4. Also, prostaglandin E1 but not leukotriene B4 enhances the guinea pig in vivo response to PAF in this model. However, in rats, none of the cyclooxygenase inhibitors, histamine antagonists, or BW755C inhibit the PAF effect of cutaneous phenomena

Synergism of diabetic and inflammatory culture conditions on reactivity of isolated small arteries

DEFF Research Database (Denmark)

Blædel, Martin Mads; Boonen, Harrie C.M.; Sams Nielsen, Anette

Background: Cardiovascular disease (CVD) is the manifestation of atherosclerosis, which has been linked to obesity, the metabolic syndrome (MS) and overt type 2 diabetes (T2DM). Vascular dysfunction has been proposed to precede atherosclerosis, and in addition, a correlation between vascular...... isolated from 8 week old male SD rats were cultured for 21 hours in Endothelial Basal Medium (EBM-2) in petri dishes and in the absence or presence of either 30 mM D-glucose, 100 nM insulin, 100 ng/mL TNFa or any combination of these. Contractile reactivity of normalised arteries was then determined...... by wire myography as a response to cumulatively increasing concentrations of noradrenaline (NA). Results: 21 hour culture of isolated mesenteric arteries significantly reduced the arteries maximal high potassium-induced contractile reactivity and increased the contractility to noradrenaline slightly...

Syncytiotrophoblast extracellular vesicles impair rat uterine vascular function via the lectin-like oxidized LDL receptor-1.

Directory of Open Access Journals (Sweden)

Floor Spaans

Full Text Available Syncytiotrophoblast extracellular vesicles (STBEVs are placenta derived particles that are released into the maternal circulation during pregnancy. Abnormal levels of STBEVs have been proposed to affect maternal vascular function. The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1 is a multi-ligand scavenger receptor. Increased LOX-1 expression and activation has been proposed to contribute to endothelial dysfunction. As LOX-1 has various ligands, we hypothesized that, being essentially packages of lipoproteins, STBEVs are able to activate the LOX-1 receptor thereby impairing vascular function via the production of superoxide and decreased nitric oxide bioavailability. Uterine arteries were obtained in late gestation from Sprague-Dawley rats and incubated for 24h with or without human STBEVs (derived from a normal pregnant placenta in the absence or presence of a LOX-1 blocking antibody. Vascular function was assessed using wire myography. Endothelium-dependent maximal vasodilation to methylcholine was impaired by STBEVs (MCh Emax: 57.7±5.9% in STBEV-incubated arteries vs. 77.8±2.9% in controls, p<0.05. This was prevented by co-incubation of STBEV-incubated arteries with LOX-1 blocking antibodies (MCh Emax: 78.8±4.3%, p<0.05. Pre-incubation of the vessels with a nitric oxide synthase inhibitor (L-NAME demonstrated that the STBEV-induced impairment in vasodilation was due to decreased nitric oxide contribution (ΔAUC 12.2±11.7 in STBEV-arteries vs. 86.5±20 in controls, p<0.05, which was abolished by LOX-1 blocking antibody (ΔAUC 98.9±17, p<0.05. In STBEV-incubated vessels, LOX-1 inhibition resulted in an increased endothelial nitric oxide synthase expression (p<0.05, to a level similar to control vessels. The oxidant scavenger, superoxide dismutase, did not improve this impairment, nor were vascular superoxide levels altered. Our data support an important role for STBEVs in impairment of vascular function via activation of

Mitofusin2 decreases intracellular cholesterol of oxidized LDL-induced foam cells from rat vascular smooth muscle cells.

Science.gov (United States)

He, Chao; Chen, Ying; Liu, Chun; Cao, Ming; Fan, Yu-jin; Guo, Xiao-mei

2013-04-01

Mitofusin2 (Mfn2) plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells (VSMCs). The purpose of this study was to investigate the effects of Mfn2 on the trafficking of intracellular cholesterol in the foam cells derived from rat VSMCs (rVSMCs) and also to investigate the effects of Mfn2 on the expression of adenosine triphosphate-binding cassette subfamily A member 1 (ABCA1), adenosine triphosphate-binding cassette subfamily G member 1 (ABCG1) and peroxisome proliferator-activated receptor gamma (PPARγ). The rVSMCs were co-cultured with oxidized low density lipoprotein (LDL, 80 μg/mL) to produce foam cells and cholesterol accumulation in cells. Before oxidized LDL treatment, different titers (20, 40 and 60 pfu/cell) of recombinant adenovirus containing Mfn2 gene (Adv-Mfn2) were added into the culture medium for 24 h to transfect the Mfn2 gene into the rVSMCs. Then the cells were harvested for analyses. The protein expression of Mfn2 was significantly higher in Adv-Mfn2-transfected group than in untransfected group (PLDL treatment, rVSMCs became irregular and their nuclei became larger, and their plasma abounded with red lipid droplets. However, the number of red lipid droplets was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group. At 48 h after oxidized LDL treatment, the intracellular cholesterol in rVSMCs was significantly increased (P0.05), the phosporylation levels of PPARγ were significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group (Pcholesterol in oxidized LDL-induced rVSMCs possibly by decreasing PPARγ phosporylation and then increasing protein expression levels of ABCA1 and ABCG1, which may be helpful to suppress the formation of foam cells.

Partly ordered synthesis and degradation of glycogen in cultured rat myotubes

DEFF Research Database (Denmark)

Elsner, Peter; Quistorff, Bjørn; Hansen, Gert H

2001-01-01

The following questions concerning glycogen synthesis and degradation were examined in cultured rat myotubes. 1) Is synthesis and degradation of the individual glycogen molecule a strictly ordered process, with the last glucosyl unit incorporated into the molecule being the first to be released...

Exendin-4, a glucagon-like peptide-1 receptor agonist, reduces intimal thickening after vascular injury

Energy Technology Data Exchange (ETDEWEB)

Goto, Hiromasa [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Nomiyama, Takashi, E-mail: tnomiyama@fukuoka-u.ac.jp [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Mita, Tomoya; Yasunari, Eisuke; Azuma, Kosuke; Komiya, Koji; Arakawa, Masayuki; Jin, Wen Long; Kanazawa, Akio [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Kawamori, Ryuzo [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Sportology Center, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Center for Therapeutic Innovations in Diabetes, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Center for Beta Cell Biology and Regeneration, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Fujitani, Yoshio; Hirose, Takahisa [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Center for Therapeutic Innovations in Diabetes, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Watada, Hirotaka, E-mail: hwatada@juntendo.ac.jp [Department of Medicine, Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan); Sportology Center, Juntendo University Graduate School of Medicine, Tokyo 113-8421 (Japan)

2011-02-04

Research highlights: {yields} Exendin-4 reduces neointimal formation after vascular injury in a mouse model. {yields} Exendin-4 dose not alter metabolic parameters in non-diabetic, non-obese mouse model. {yields} Exendin-4 reduces PDGF-induced cell proliferation in cultured SMCs. {yields} Exendin-4 may reduces neointimal formation after vascular injury at least in part through its direct action on SMCs. -- Abstract: Glucagon-like peptide-1 is a hormone secreted by L cells of the small intestine and stimulates glucose-dependent insulin response. Glucagon-like peptide-1 receptor agonists such as exendin-4 are currently used in type 2 diabetes, and considered to have beneficial effects on the cardiovascular system. To further elucidate the effect of glucagon-like peptide-1 receptor agonists on cardiovascular diseases, we investigated the effects of exendin-4 on intimal thickening after endothelial injury. Under continuous infusion of exendin-4 at 24 nmol/kg/day, C57BL/6 mice were subjected to endothelial denudation injury of the femoral artery. Treatment of mice with exendin-4 reduced neointimal formation at 4 weeks after arterial injury without altering body weight or various metabolic parameters. In addition, in vitro studies of isolated murine, rat and human aortic vascular smooth muscle cells showed the expression of GLP-1 receptor. The addition of 10 nM exendin-4 to cultured smooth muscle cells significantly reduced their proliferation induced by platelet-derived growth factor. Our results suggested that exendin-4 reduced intimal thickening after vascular injury at least in part by the suppression of platelet-derived growth factor-induced smooth muscle cells proliferation.

Exendin-4, a glucagon-like peptide-1 receptor agonist, reduces intimal thickening after vascular injury

International Nuclear Information System (INIS)

Goto, Hiromasa; Nomiyama, Takashi; Mita, Tomoya; Yasunari, Eisuke; Azuma, Kosuke; Komiya, Koji; Arakawa, Masayuki; Jin, Wen Long; Kanazawa, Akio; Kawamori, Ryuzo; Fujitani, Yoshio; Hirose, Takahisa; Watada, Hirotaka

2011-01-01

Research highlights: → Exendin-4 reduces neointimal formation after vascular injury in a mouse model. → Exendin-4 dose not alter metabolic parameters in non-diabetic, non-obese mouse model. → Exendin-4 reduces PDGF-induced cell proliferation in cultured SMCs. → Exendin-4 may reduces neointimal formation after vascular injury at least in part through its direct action on SMCs. -- Abstract: Glucagon-like peptide-1 is a hormone secreted by L cells of the small intestine and stimulates glucose-dependent insulin response. Glucagon-like peptide-1 receptor agonists such as exendin-4 are currently used in type 2 diabetes, and considered to have beneficial effects on the cardiovascular system. To further elucidate the effect of glucagon-like peptide-1 receptor agonists on cardiovascular diseases, we investigated the effects of exendin-4 on intimal thickening after endothelial injury. Under continuous infusion of exendin-4 at 24 nmol/kg/day, C57BL/6 mice were subjected to endothelial denudation injury of the femoral artery. Treatment of mice with exendin-4 reduced neointimal formation at 4 weeks after arterial injury without altering body weight or various metabolic parameters. In addition, in vitro studies of isolated murine, rat and human aortic vascular smooth muscle cells showed the expression of GLP-1 receptor. The addition of 10 nM exendin-4 to cultured smooth muscle cells significantly reduced their proliferation induced by platelet-derived growth factor. Our results suggested that exendin-4 reduced intimal thickening after vascular injury at least in part by the suppression of platelet-derived growth factor-induced smooth muscle cells proliferation.

Isoproterenol attenuates high vascular pressure-induced permeability increases in isolated rat lungs.

Science.gov (United States)

Parker, J C; Ivey, C L

1997-12-01

To separate the contributions of cellular and basement membrane components of the alveolar capillary barrier to the increased microvascular permeability induced by high pulmonary venous pressures (Ppv), we subjected isolated rat lungs to increases in Ppv, which increased capillary filtration coefficient (Kfc) without significant hemorrhage (31 cmH2O) and with obvious extravasation of red blood cells (43 cmH2O). Isoproterenol (20 microM) was infused in one group (Iso) to identify a reversible cellular component of injury, and residual blood volumes were measured to assess extravasation of red blood cells through ruptured basement membranes. In untreated lungs (High Ppv group), Kfc increased 6.2 +/- 1.3 and 38.3 +/- 15.2 times baseline during the 31 and 43 cmH2O Ppv states. In Iso lungs, Kfc was 36.2% (P Kfc increases at moderate Ppv, possibly because of an endothelial effect, but it did not affect red cell extravasation at higher vascular pressures.

Inhibiting trophoblast PAR-1 overexpression suppresses sFlt-1-induced anti-angiogenesis and abnormal vascular remodeling: a possible therapeutic approach for preeclampsia.

Science.gov (United States)

Zhao, Yin; Zheng, YanFang; Liu, XiaoXia; Luo, QingQing; Wu, Di; Liu, XiaoPing; Zou, Li

2018-03-01

Is it possible to improve vascular remodeling by inhibiting the excessive expression of protease-activated receptor 1 (PAR-1) in trophoblast of abnormal placenta? Inhibition of trophoblast PAR-1 overexpression may promote placental angiogenesis and vascular remodeling, offering an alternative therapeutic approach for preeclampsia. PAR-1 is high-affinity receptor of thrombin. Thrombin increases sFlt-1 secretion in trophoblast via the activation of PAR-1. It is reported that the expression of both thrombin and PAR-1 expression are increased in placentas of preeclampsia patients compared with normal placentas. Trophoblast cells were transfected with PAR-1 short hairpin RNA (shRNA) or PAR-1 overexpression plasmids in vitro. Tube formation assays and a villus-decidua co-culture system were used to study the effect of PAR-1 inhibition on placental angiogenesis and vascular remodeling, respectively. Placentas from rats with preeclampsia were transfected with PAR-1 shRNA to confirm the effect of inhibiting PAR-1 overexpression in placenta. The trophoblast cell line HTR-8/SVneo was transfected with PAR-1 shRNA or PAR-1 overexpression plasmids. After 48 h, supernatant was collected and the level of sFlt-1 secretion was measured by ELISA. Human umbilical cord epithelial cells and a villus-decidua co-culture system were treated with conditioned media to study the effect of PAR-1 inhibition on tube formation and villi vascular remodeling. A preeclampsia rat model was established by intraperitoneal injection of L-NAME. Plasmids were injected into the placenta of the preeclampsia rats and systolic blood pressure was measured on Days 15 and 19. The effect of different treatments was evaluated by proteinuria, placental weights, fetal weights and fetal numbers in study and control groups. The level of serum sFlt-1 in rats with preeclampsia was also measured. Changes in the placenta microvessels were studied by histopathological staining. PAR-1 shRNA inhibited PAR-1 expression and

Plasma-mediated vascular dysfunction in the reduced uterine perfusion pressure model of preeclampsia: a microvascular characterization.

LENUS (Irish Health Repository)

Walsh, Sarah K

2012-01-31

Preeclampsia is associated with widespread maternal vascular dysfunction, which is thought to be mediated by circulating factor(s). The aim of the study was to characterize vascular function in the reduced uterine perfusion pressure (RUPP) rat model of preeclampsia and to investigate the role of plasma factors in mediating any observed changes in vascular reactivity. Mean arterial blood pressure and vascular function were measured in RUPP and control rats. Mesenteric vessels from both virgin and pregnant rats were exposed for 1 hour or overnight to plasma from both RUPP and control rats and their vascular function assessed. RUPP rats were characterized by severe hypertension, restricted fetal growth, and reduced placental weight (P<0.001). Vasorelaxation was impaired in resistance vessels from RUPP compared with control rats (acetylcholine: R(max) 70+\\/-3 versus 92+\\/-1 [NP] and 93+\\/-3% [sham], P<0.01; bradykinin: 40+\\/-2 versus 62+\\/-2 [NP] and 59+\\/-4% [sham], P<0.001). Incubation of vessels from pregnant (but not virgin) animals with RUPP plasma overnight resulted in an attenuation of vasorelaxant responses (acetylcholine: 63+\\/-7 versus 86+\\/-2%, P<0.05; bradykinin: 35+\\/-5 versus 55+\\/-6%, P<0.001). The residual relaxant response in RUPP plasma-treated vessels was not further attenuated after treatment with N(omega)-nitro-l-arginine methyl ester (acetylcholine: 57+\\/-7 versus 63+\\/-7%, ns; bradykinin: 37+\\/-5 versus 35+\\/-5%, ns). The RUPP rat model is characterized by an impaired response to vasodilators which may be attributable to one or more circulating factors. This plasma-mediated endothelial dysfunction appears to be a pregnancy-dependent effect. Furthermore, nitric oxide-mediated vasorelaxation appears to be absent in RUPP plasma-treated vessels.

Increased Contractile Response to Noradrenaline Induced By Factors Associated with the Metabolic Syndrome in Cultured Small Mesenteric Arteries

DEFF Research Database (Denmark)

Blædel, Martin; Sams, Anette; Boonen, Harrie C M

2016-01-01

UNLABELLED: This study investigated the effect of the metabolic syndrome associated risk factors hyperglycemia (glucose [Glc]), hyperinsulinemia (insulin [Ins]) and low-grade inflammation (tumor necrosis factor α [TNFα]) on the vasomotor responses of resistance arteries. Isolated small mesenteric...... arteries from 3-month-old Sprague-Dawley rats, were suspended for 21-23 h in tissue cultures containing either elevated Glc (30 mmol/l), Ins (100 nmol/l), TNFα (100 ng/ml) or combinations thereof. After incubation, the vascular response to noradrenaline (NA), phenylephrine, isoprenaline and NA...... in vascular tone....

Structural properties of lipid reconstructs and lipid composition of normotensive and hypertensive rat vascular smooth muscle cell membranes

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T.R. Oliveira

2009-09-01

Full Text Available Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR and normotensive control rat strains (WKY and NWR. Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.

Effect of various chemicals on the metabolism of benzo(a)pyrene by cultured rat colon

DEFF Research Database (Denmark)

Autrup, Herman; Harris, Curtis C.; Fugaro, Steven

1977-01-01

The effect of various co- and anti-carcinogens of colon carcinogenesis on the metabolism of benzo(a)pyrene (BP) in cultured rat colon is reported. Rat colon enzymatically converted BP into metabolites which bind to cellular macromolecules i.e., DNA and protein. Activity of aryl hydrocarbon...

Protective Effect of Edaravone against Carbon Monoxide Induced Apoptosis in Rat Primary Cultured Astrocytes

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Xiaodan Xu

2017-01-01

Full Text Available Objective. To observe the protective effect of edaravone (Eda on astrocytes after prolonged exposure to carbon monoxide (CO and further to investigate the potential mechanisms of Eda against CO-induced apoptosis. Methods. The rat primary cultured astrocytes were cultured in vitro and exposed to 1% CO for 24 h after being cultured with different concentrations of Eda. MTT assay was used to detect the cytotoxicity of CO. Flow cytometry was used to detect the apoptosis rate, membrane potential of mitochondria, and ROS level. The mRNA and protein expressions of Bcl-2, Bax, and caspase-3 were assessed by real-time PCR and Western blotting analysis, respectively. Results. Eda can significantly suppress cytotoxicity of CO, and it can significantly increase membrane potential of mitochondria and Bcl-2 expressions and significantly suppress the apoptosis rate, ROS level, Bax, and caspase-3 expressions. Conclusion. Eda protects against CO-induced apoptosis in rat primary cultured astrocytes through decreasing ROS production and subsequently inhibiting mitochondrial apoptosis pathway.

Dopaminergic differentiation of human neural stem cells mediated by co-cultured rat striatal brain slices

DEFF Research Database (Denmark)

Anwar, Mohammad Raffaqat; Andreasen, Christian Maaløv; Lippert, Solvej Kølvraa

2008-01-01

differentiation, we co-cultured cells from a human neural forebrain-derived stem cell line (hNS1) with rat striatal brain slices. In brief, coronal slices of neonatal rat striatum were cultured on semiporous membrane inserts placed in six-well trays overlying monolayers of hNS1 cells. After 12 days of co......Properly committed neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. To establish a setting for identification of secreted neural compounds promoting dopaminergic...

Cultured rat and purified human Pneumocystis carinii stimulate intra- but not extracellular free radical production in human neutrophils

DEFF Research Database (Denmark)

Jensen, T; Aliouat, E M; Lundgren, B

1998-01-01

The production of free radicals in human neutrophils was studied in both Pneumocystis carinii derived from cultures of L2 rat lung epithelial-like cells and Pneumocystis carinii purified from human lung. Using the cytochrome C technique, which selectively measured extracellular superoxide...... generation, hardly any free radical production was observed after stimulation with cultured rat-derived P. carinii. A chemiluminescence technique, which separately measured intra- and extracellular free radical production, was subsequently employed to differentiate the free radical generation....... It was established that 1) P. carinii stimulated intra- but not extracellular free radical production in human neutrophils, 2) opsonized cultured rat-derived P. carinii stimulated human neutrophils to a strong intracellular response of superoxide production, and 3) opsonized P. carinii, purified from human lung also...

Optical spectroscopy of radiotherapy and photodynamic therapy responses in normal rat skin shows vascular breakdown products

Science.gov (United States)

Teles de Andrade, Cintia; Nogueira, Marcelo S.; Kanick, Stephen C.; Marra, Kayla; Gunn, Jason; Andreozzi, Jacqueline; Samkoe, Kimberley S.; Kurachi, Cristina; Pogue, Brian W.

2016-03-01

Photodynamic therapy (PDT) and radiotherapy are non-systemic cancer treatment options with different mechanisms of damage. So combining these techniques has been shown to have some synergy, and can mitigate their limitations such as low PDT light penetration or radiotherapy side effects. The present study monitored the induced tissue changes after PDT, radiotherapy, and a combination protocol in normal rat skin, using an optical spectroscopy system to track the observed biophysical changes. The Wistar rats were treated with one of the protocols: PDT followed by radiotherapy, PDT, radiotherapy and radiotherapy followed by PDT. Reflectance spectra were collected in order to observe the effects of these combined therapies, especially targeting vascular response. From the reflectance, information about oxygen saturation, met-hemoglobin and bilirubin concentration, blood volume fraction (BVF) and vessel radius were extracted from model fitting of the spectra. The rats were monitored for 24 hours after treatment. Results showed that there was no significant variation in the vessel size or BVF after the treatments. However, the PDT caused a significant increase in the met-hemoglobin and bilirubin concentrations, indicating an important blood breakdown. These results may provide an important clue on how the damage establishment takes place, helping to understand the effect of the combination of those techniques in order to verify the existence of a known synergistic effect.

Differential feedback regulation of cholesterol 7α-hydroxylase mRNA and transcriptional activity by rat bile acids in primary monolayer cultures of rat hepatocytes

NARCIS (Netherlands)

Twisk, J.; Lehmann, E.M.; Princen, H.M.G.

1993-01-01

We have used primary monolayer cultures of rat hepatocytes to study the effects of physiological concentrations of various bile acids, commonly found in bile of normal rats, on the mechanism of regulation of cholesterol 7α-hydroxylase and bile acid synthesis. Addition of taurocholic acid, the most

Adipokine CTRP6 improves PPARγ activation to alleviate angiotensin II-induced hypertension and vascular endothelial dysfunction in spontaneously hypertensive rats

International Nuclear Information System (INIS)

Chi, Liyi; Hu, Xiaojing; Zhang, Wentao; Bai, Tiao; Zhang, Linjing; Zeng, Hua; Guo, Ruirui; Zhang, Yanhai; Tian, Hongyan

2017-01-01

Angiotensin II (AngII) is the most important component of angiotensin, which has been regarded as a major contributor to the incidence of hypertension and vascular endothelial dysfunction. The adipocytokine C1q/TNF-related protein 6 (CTRP6) was recently reported to have multiple protective effects on cardiac and cardiovascular function. However, the exact role of CTRP6 in the progression of AngII induced hypertension and vascular endothelial function remains unclear. Here, we showed that serum CTRP6 content was significantly downregulated in SHRs, accompanied by a marked increase in arterial systolic pressure and serum AngII, CRP and ET-1 content. Then, pcDNA3.1-mediated CTRP6 delivery or CTRP6 siRNA was injected into SHRs. CTRP6 overexpression caused a significant decrease in AngII expression and AngII-mediated hypertension and vascular endothelial inflammation. In contrast, CTRP6 knockdown had the opposite effect to CTRP6 overexpression. Moreover, we found that CTRP6 positively regulated the activation of the ERK1/2 signaling pathway and the expression of peroxisome proliferator-activated receptor γ (PPARγ), a recently proven negative regulator of AngII, in the brain and vascular endothelium of SHRs. Finally, CTRP6 was overexpressed in endothelial cells, and caused a significant increase in PPARγ activation and suppression in AngII-mediated vascular endothelial dysfunction and apoptosis. The effect of that could be rescued by the ERK inhibitor PD98059. In contrast, silencing CTRP6 suppressed PPARγ activation and exacerbated AngII-mediated vascular endothelial dysfunction and apoptosis. In conclusion, CTRP6 improves PPARγ activation and alleviates AngII-induced hypertension and vascular endothelial dysfunction. - Highlights: • Serum CTRP6 was significantly decreased in spontaneously hypertensive rats (SHRs). • CTRP6 positively regulated the activation of the ERK1/2 signaling pathway. • CTRP6 negatively regulates PPARγ mediated Angiotensin II (Ang

Vascular mechanism of action of endothelin-1: Effect of Ca2+ antagonists

International Nuclear Information System (INIS)

Chabrier, P.E.; Auguet, M.; Roubert, P.; Lonchampt, M.O.; Gillard, V.; Guillon, J.M.; Delaflotte, S.; Braquet, P.

1989-01-01

The vasoconstrictive properties of the endothelium-derived peptide, endothelin-1 (ET-1), were investigated on rat isolated aorta and on cultured rat aortic smooth muscle cells. In rat isolated aorta, endothelin-1 induced a slow and sustained contraction in a Ca2+-free medium; after calcium readmission, an additional sustained contraction was elicited. In vascular smooth muscle cells, endothelin-1 provoked a dose-dependent Ca2+ influx that was not inhibited by calcium entry blockers (nifedipine, D 600, or diltiazem). In these cells, [ 125 I]-endothelin-1 bound to a specific, saturable, and high affinity recognition site (Kd about 10(-9) M and Bmax = 52 +/- 2 fmol/10(6) cells). The binding was not reversible and not affected by calcium antagonists. These data do not support the hypothesis that endothelin-1 acts as an endogenous agonist of the voltage-dependent Ca2+ channels. The action of endothelin-1 can be separated into two components: one dependent on Ca2+ influx but insensitive to calcium antagonists and another independent of extracellular Ca2+. The irreversible binding of endothelin-1 may reflect an internalization of the ligand inside the cell membrane, leading to multiple contractile events

Short-Term Therapy with Rosiglitazone, a PPAR-γ Agonist, Improves Metabolic Profile and Vascular Function in Nonobese Lean Wistar Rats

OpenAIRE

Naderali, Mohammad M.; Itua, Imose; Abubakari, Abdul-Razak; Naderali, Ebrahim K.

2012-01-01

A number of preclinical and clinical studies have reported blood-pressure-lowering benefits of thiazolidinediones in diabetic subjects and animal models of diabetes. This study was designed to further elucidate vascular effects of rosiglitazone, on healthy nonobese, lean animals. Adult male Wistar rats were randomized and assigned to control and rosiglitazone-treated groups and were dosed daily with either vehicle or rosiglitazone (10 mg kg−1 day−1) by oral gavage for 5 days. Compared with co...

[Lessening effect of hypoxia-preconditioned rat cerebrospinal fluid on oxygen-glucose deprivation-induced injury of cultured hippocampal neurons in neonate rats and possible mechanism].

Science.gov (United States)

Niu, Jing-Zhong; Zhang, Yan-Bo; Li, Mei-Yi; Liu, Li-Li

2011-12-25

The present study was to investigate the effect of cerebrospinal fluid (CSF) from the rats with hypoxic preconditioning (HPC) on apoptosis of cultured hippocampal neurons in neonate rats under oxygen glucose deprivation (OGD). Adult Wistar rats were exposed to 3 h of hypoxia for HPC, and then their CSF was taken out. Cultured hippocampal neurons from the neonate rats were randomly divided into four groups (n = 6): normal control group, OGD group, normal CSF group and HPC CSF group. OGD group received 1.5 h of incubation in glucose-free Earle's solution containing 1 mmol/L Na2S2O4, and normal and HPC CSF groups were subjected to 1 d of corresponding CSF treatments followed by 1.5 h OGD. The apoptosis of neurons was analyzed by confocal laser scanning microscope and flow cytometry using Annexin V/PI double staining. Moreover, protein expressions of Bcl-2 and Bax were detected by immunofluorescence. The results showed that few apoptotic cells were observed in normal control group, whereas the number of apoptotic cells was greatly increased in OGD group. Both normal and HPC CSF could decrease the apoptosis of cultured hippocampal neurons injured by OGD (P neurons by up-regulating expression of Bcl-2 and down-regulating expression of Bax.

Use of 5-Bromodeoxyuridine and irradiation for the estimation of the myoblast and myocyte content of primary rat heart cell cultures

International Nuclear Information System (INIS)

Masse, M.J.O.; Harary, I.

1980-01-01

A method for killing dividing cells was adapted for the elimination of dividing heart muscle cells (myoblasts) in cultures. We have used this method to demonstrate their presence and to estimate their number as well as the number of nondividing heart muscle cells (myocytes) in the neo-natal rat heart. Cells were cultivated in BUdR (5-bromodeoxyuridine) 10 -4 M for 3 days and then irradiated with long uv light. The selective elimination of dividing cells led to a loss of myosin Ca 2+ -activated ATPase in the cultures. The percent of ATPase left after irradiation was 32% of the control in cultures derived from 1-day postnatal rats and 48% in cultures from 4-day postnatal rats. This reflects an in vivo shift of myoblasts to myocytes in the muscle cell population as the rat ages

An interaction of renin-angiotensin and kallikrein-kinin systems contributes to vascular hypertrophy in angiotensin II-induced hypertension: in vivo and in vitro studies.

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Graziela S Ceravolo

Full Text Available The kallikrein-kinin and renin-angiotensin systems interact at multiple levels. In the present study, we tested the hypothesis that the B1 kinin receptor (B1R contributes to vascular hypertrophy in angiotensin II (ANG II-induced hypertension, through a mechanism involving reactive oxygen species (ROS generation and extracellular signal-regulated kinase (ERK1/2 activation. Male Wistar rats were infused with vehicle (control rats, 400 ng/Kg/min ANG II (ANG II rats or 400 ng/Kg/min ANG II plus B1 receptor antagonist, 350 ng/Kg/min des-Arg(9-Leu(8-bradykinin (ANGII+DAL rats, via osmotic mini-pumps (14 days or received ANG II plus losartan (10 mg/Kg, 14 days, gavage - ANG II+LOS rats. After 14 days, ANG II rats exhibited increased systolic arterial pressure [(mmHg 184 ± 5.9 vs 115 ± 2.3], aortic hypertrophy; increased ROS generation [2-hydroxyethidium/dihydroethidium (EOH/DHE: 21.8 ± 2.7 vs 6.0 ± 1.8] and ERK1/2 phosphorylation (% of control: 218.3 ± 29.4 vs 100 ± 0.25]. B1R expression was increased in aortas from ANG II and ANG II+DAL rats than in aortas from the ANG II+LOS and control groups. B1R antagonism reduced aorta hypertrophy, prevented ROS generation (EOH/DHE: 9.17 ± 3.1 and ERK1/2 phosphorylation (137 ± 20.7% in ANG II rats. Cultured aortic vascular smooth muscle cells (VSMC stimulated with low concentrations (0.1 nM of ANG II plus B1R agonist exhibited increased ROS generation, ERK1/2 phosphorylation, proliferating-cell nuclear antigen expression and [H3]leucine incorporation. At this concentration, neither ANG II nor the B1R agonist produced any effects when tested individually. The ANG II/B1R agonist synergism was inhibited by losartan (AT1 blocker, 10 µM, B1R antagonist (10 µM and Tiron (superoxide anion scavenger, 10 mM. These data suggest that B1R activation contributes to ANG II-induced aortic hypertrophy. This is associated with activation of redox-regulated ERK1/2 pathway that controls aortic smooth muscle cells growth

Improvement of vascular function by acute and chronic treatment with the GPR30 agonist G1 in experimental diabetes mellitus.

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Zi-lin Li

Full Text Available The G-protein coupled estrogen receptor 30 (GPR30 is a seven-transmembrane domain receptor that mediates rapid estrogen responses in a wide variety of cell types. This receptor is highly expressed in the cardiovascular system, and exerts vasodilatory effects. The objective of the present study was to investigate the effects of GPR30 on vascular responsiveness in diabetic ovariectomized (OVX rats and elucidate the possible mechanism involved. The roles of GPR30 were evaluated in the thoracic aorta and cultured endothelial cells. The GPR30 agonist G1 induced a dose-dependent vasodilation in the thoracic aorta of the diabetic OVX rats, which was partially attenuated by the nitric oxide synthase (NOS inhibitor, nitro-L-arginine methylester (L-NAME and the GPR30-selective antagonist G15. Dose-dependent vasoconstrictive responses to phenylephrine were attenuated significantly in the rings of the thoracic aorta following the acute G1 administration in the diabetic OVX rats. This effect of G1 was abolished partially by L-NAME and G15. The acute administration of G1 increased significantly the eNOS activity and the concentration of NO in the endothelial cells exposed to high glucose. G1 treatment induced an enhanced endothelium-dependent relaxation to acetylcholine (Ach in the diabetic OVX rats. Further examination revealed that G1 induced vasodilation in the diabetic OVX rats by increasing the phosphorylation of eNOS. These findings provide preliminary evidence that GPR30 activation leads to eNOS activation, as well as vasodilation, to a certain degree and has beneficial effects on vascular function in diabetic OVX rats.

Characteristics of monolayer culture of bone marrow cells of rats bearing 239Pu-induced osteosarcoma

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Bukhtoyarova, Z.M.; Lemberg, V.K.

1984-01-01

The report is concerned with a monolayer culture of bone marrow cells of rats in which optimal blastogenic dose (92.5 kBq/kg) induced osteosarcoma. The cell culture showed an enhanced rate of fibroblast-like cell proliferation (increased number of mitoses and symplasts and larger colonies of cells), apparent signs of radiation in ury (pathologic mitoses, chromosome aberrations and gaps) as well as an increase in ploidy. Diffusion chamber measurements demonstrated osteogenic precursor-cells in osteosarcoma-bearing rats to be highly capable of bone formation. This relatively high ability seems to occur outside bone marrow as well

Hyperglycaemia in pregnant rats causes sex-related vascular dysfunction in adult offspring: role of cyclooxygenase-2.

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de Sá, Francine Gomes; de Queiroz, Diego Barbosa; Ramos-Alves, Fernanda Elizabethe; Santos-Rocha, Juliana; da Silva, Odair Alves; Moreira, Hicla Stefany; Leal, Geórgia Andrade; da Rocha, Marcelo Aurélio; Duarte, Gloria Pinto; Xavier, Fabiano Elias

2017-08-01

What is the central question of this study? Hyperglycaemia during pregnancy induces vascular dysfunction and hypertension in male offspring. Given that female offspring from other fetal programming models are protected from the effects of fetal insult, the present study investigated whether there are sex differences in blood pressure and vascular function in hyperglycaemia-programmed offspring. What is the main finding and its importance? We demonstrated that hyperglycaemia in pregnant rats induced vascular dysfunction and hypertension only in male offspring. We found sex differences in oxidative stress and cyclooxygenase-2-derived prostanoid production that might underlie the vascular dysfunction. These differences, particularly in resistance arteries, may in part explain the absence of hypertension in female offspring born to hyperglycaemic dams. Exposure to maternal hyperglycaemia induces hypertension and vascular dysfunction in adult male offspring. Given that female offspring from several fetal programming models are protected from the effects of fetal insult, in this study we analysed possible differences relative to sex in blood pressure and vascular function in hyperglycaemia-programmed offspring. Hyperglycaemia was induced on day 7 of gestation (streptozotocin, 50 mg kg -1 ). Blood pressure, acetylcholine and phenylephrine or noradrenaline responses were analysed in the aorta and mesenteric resistance arteries of 3-, 6- and 12-month-old male and female offspring. Thromboxane A 2 release was analysed with commercial kits and superoxide anion (O 2 - ) production by dihydroethidium-emitted fluorescence. Male but not female offspring of hyperglycaemic dams (O-DR) had higher blood pressure than control animals (O-CR). Contraction in response to phenylephrine increased and relaxation in response to acetylcholine decreased only in the aorta from 12-month-old male O-DR and not in age-matched O-CR. Contractile and vasodilator responses were preserved in both the

[Association between pulmonary vascular remodeling and expression of hypoxia-inducible factor-1α, endothelin-1 and inducible nitric oxide synthase in pulmonary vessels in neonatal rats with hypoxic pulmonary hypertension].

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Wang, Jian-Rong; Zhou, Ying; Sang, Kui; Li, Ming-Xia

2013-02-01

To investigate the association between pulmonary vascular remodeling and expression of hypoxia-inducible factor-1α (HIF-1α), endothelin-1 (ET-1) and inducible nitric oxide synthase (iNOS) in pulmonary vessels in neonatal rats with hypoxic pulmonary hypertension (HPH). A neonatal rat model of HPH was established as an HPH group, and normal neonatal rats were enrolled as a control group. The mean pulmonary arterial pressure (mPAP) was measured. The percentage of medial thickness to outer diameter of the small pulmonary arteries (MT%) and the percentage of medial cross-section area to total cross-section area of the pulmonary small arteries (MA%) were measured as the indicators for pulmonary vascular remodeling. The immunohistochemical reaction intensities for HIF-1α, ET-1 and iNOS and their mRNA expression in lung tissues of neonatal rats were measured. Correlation analysis was performed to determine the relationship between pulmonary vascular remodeling and mRNA expression of HIF-1α, ET-1 and iNOS. The mPAP of the HPH group kept increasing on days 3, 5, 7, 10, 14, and 21 of hypoxia, with a significant difference compared with the control group (P<0.05). The HPH group had significantly higher MT% and MA% than the control group from day 7 of hypoxia (P<0.05). HIF-1α protein expression increased significantly on days 3, 5, 7 and 10 days of hypoxia, and HIF-1α mRNA expression increased significantly on days 3, 5 and 7 days of hypoxia in the HPH group compared with the control group (P<0.05). ET-1 protein expression increased significantly on days 3, 5 and 7 days of hypoxia and ET-1 mRNA expression increased significantly on day 3 of hypoxia in the HPH group compared with the control group (P<0.05). Both iNOS protein and mRNA expression were significantly higher on days 3, 5 and 7 days of hypoxia than the control group (P<0.05). Both MT% and MA% were positively correlated with HIF-1α mRNA expression (r=0.835 and 0.850 respectively; P<0.05). Pulmonary vascular

Inhibition of MAPK and PKC pathways by 60Co γ-radiation in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Jia Guanghong; Ma Yexin; Xiao Jianming

2002-01-01

Objective: To investigate the signal transduction pathways inhibited by 60 Co γ-radiation in cultured vascular smooth muscle cells (VSMC). Methods: The cultured VSMC were irradiated with 60 Co γ-radiation of 3.5, 7.0 and 14 Gy respectively. VSMC proliferation was measured by 3 H-TdR incorporation, while PKC, MAPK activities were determined by radioactivity assay. Results: Proliferation of VSMC was inhibited by 7.0, 14 Gy 60 Co γ-irradiation and the activities of PKC, MAPK were decreased significantly. Conclusion: Inhibitory effect of 7.0, 14 Gy 60 Co γ-irradiation on proliferation of VSMC might be resulted from decrease of the activity of PKC, MAPK

Protective effects on vascular endothelial cell in N'-nitro-L-arginine (L-NNA)-induced hypertensive rats from the combination of effective components of Uncaria rhynchophylla and Semen Raphani.

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Li, Yunlun; Yang, Wenqing; Zhu, Qingjun; Yang, Jinguo; Wang, Zhen

2015-08-01

Endothelial dysfunction is closely associated with hypertension. Protection of vascular endothelial cell is the key to prevention and treatment of hypertension. Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid, isolated from traditional Chinese medicine Uncaria rbyncbopbylla and Semen Raphani respectively, exhibit properties of anti-hypertension and protection of blood vessels. In the present study, we observed the protective effect of the combined use of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid to the vascular endothelial cell in N'-nitro-L-arginine-induced hypertensive rats and investigate the preliminary mechanism. Blood pressure was detected by non-invasive rats tail method to observe the anti-hypertension effect of drugs. Scanning electron microscopy was used to observe the integrity or shedding state of vascular endothelial cell. The amount of circulating endothelial cells and CD54 and CD62P expression on circulating endothelial cells were tested to evaluate the endothelium function. In this study, we found that the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid compatibility can effectively lower the blood pressure, improve the structural integrity of vascular endothelium, and significantly reduce the number of circulating endothelial cells. Furthermore, the mean fluorescence intensity of CD54 and CD62P expressed showed decrease after the intervention of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid compatibility. In conclusion, the combination of effective components of the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid demonstrated good antihypertension effect and vascular endothelium protective effect. The preliminary mechanism of the protective effect may attribute to relieve the overall low-grade inflammation.

Neuroprotective effect of selective DPP-4 inhibitor in experimental vascular dementia.

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Jain, Swati; Sharma, Bhupesh

2015-12-01

Vascular risk factors are associated with a higher incidence of dementia. Diabetes mellitus is considered as a main risk factor for Alzheimer's disease and vascular dementia. Both forms of dementia are posing greater risk to the world population and are increasing at a faster rate. In the past we have reported the induction of vascular dementia by experimental diabetes. This study investigates the role of vildagliptin, a dipeptidyl peptidase-4 inhibitor in the pharmacological interdiction of pancreatectomy diabetes induced vascular endothelial dysfunction and subsequent vascular dementia in rats. Attentional set shifting and Morris water-maze test were used for assessment of learning and memory. Vascular endothelial function, blood brain barrier permeability, serum glucose, serum nitrite/nitrate, oxidative stress (viz. aortic superoxide anion, brain thiobarbituric acid reactive species and brain glutathione), brain calcium and inflammation (myeloperoxidase) were also estimated. Pancreatectomy diabetes rats have shown impairment of endothelial function, blood brain barrier permeability, learning and memory along with increase in brain inflammation, oxidative stress and calcium. Administration of vildagliptin has significantly attenuated pancreatectomy induced impairment of learning, memory, endothelial function, blood brain barrier permeability and biochemical parameters. It may be concluded that vildagliptin, a dipeptidyl peptidase-4 inhibitor may be considered as potential pharmacological agents for the management of pancreatectomy induced endothelial dysfunction and subsequent vascular dementia. The selective modulators of dipeptidyl peptidase-4 may further be explored for their possible benefits in vascular dementia. Copyright © 2015 Elsevier Inc. All rights reserved.

Functional characterization of apical transporters expressed in rat proximal tubular cells (PTCs) in primary culture.

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Nakanishi, Takeo; Fukushi, Akimasa; Sato, Masanobu; Yoshifuji, Mayuko; Gose, Tomoka; Shirasaka, Yoshiyuki; Ohe, Kazuyo; Kobayashi, Masato; Kawai, Keiichi; Tamai, Ikumi

2011-12-05

Since in vitro cell culture models often show altered apical transporter expression, they are not necessarily suitable for the analysis of renal transport processes. Therefore, we aimed here to investigate the usefulness of primary-cultured rat proximal tubular cells (PTCs) for this purpose. After isolation of renal cortical cells from rat kidneys, PTCs were enriched and the gene expression and function of apical transporters were analyzed by means of microarray, RT-PCR and uptake experiments. RT-PCR confirmed that the major apical transporters were expressed in rat PTCs. Na(+)-dependent uptake of α-methyl-d-glucopyranoside (αMG), ergothioneine and carnitine by the PTCs suggests functional expression of Sglts, Octn1 and Octn2, respectively. Inhibition of pH-dependent glycylsarcosine uptake by low concentration of cephalexin, which is a β-lactam antibiotics recognized by Pepts, indicates a predominant role of high affinity type Pept2, but not low affinity type Pept1, in the PTCs. Moreover, the permeability ratio of [(14)C]αMG (apical to basolateral/basolateral to apical) across PTCs was 4.3, suggesting that Sglt-mediated reabsorptive transport is characterized. In conclusion, our results indicate that rat PTCs in primary culture are found to be a promising in vitro model to evaluate reabsorption processes mediated at least by Sglts, Pept2, Octn1 and Octn2.

Hepatoprotective effects of Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] on alcohol-damaged primary rat hepatocyte culture in vitro.

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Jiang, Wenhua; Bian, Yuzhu; Wang, Zhenghui; Chang, Thomas Ming Swi

2017-02-01

We have prepared a novel nanobiotherapeutic, Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase], which not only transports both oxygen and carbon dioxide but also a therapeutic antioxidant. Our previous study in a severe sustained 90 min hemorrhagic shock rat model shows that it has a hepatoprotective effect. We investigate its hepatoprotective effect further in this present report using an alcohol-damaged primary hepatocyte culture model. Results show that it significantly reduced ethanol-induced AST release, lipid peroxidation, and ROS production in rat primary hepatocytes culture. It also significantly enhanced the viability of ethanol-treated hepatocytes. Thus, the result shows that Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] also has some hepatoprotective effects against alcohol-induced injury in in vitro rat primary hepatocytes cell culture. This collaborate our previous observation of its hepatoprotective effect in a severe sustained 90-min hemorrhagic shock rat model.

Tongqiao Huoxue Decoction ameliorates learning and memory defects in rats with vascular dementia by up-regulating the Ca(2+)-CaMKII-CREB pathway.

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Ge, Chao-Liang; Wang, Xin-Ming; Huang, Zhao-Gang; Xia, Quan; Wang, Ning; Xu, Du-Juan

2015-11-01

The present study was aimed at determining the effects of Tongqiao Huoxue Decoction (TQHXD) on the Ca(2+)-CaMKII-CREB pathway and the memory and learning capacities of rats with vascular dementia (VD). The rat VD model was established by using an improved bilateral carotid artery ligation method. The Morris water maze experiment was used to evaluate the ethology of the VD rats following treatments with TQHXD at 3.01, 6.02, and 12.04 g·kg(-1) per day for 31 days. At the end of experiment, the hippocampus were harvested and analyzed. Western blotting and RT-PCR were used to measure the expression levels of calmodulin-binding protein kinase II(CaMKII), protein kinase A(PKA), cAMP-response element binding protein(CREB), and three N-methyl-D-aspartic acid receptor subunits (NR1, NR2A, and NR2B). Our results revealed that TQHXD could alleviate the loss of learning abilities and increase the memory capacity (P < 0.05 and P < 0.01 vs the model group, respectively). The treatment with 6.02 and 12.04 g·kg(-1) of TQHXD significantly up-regulated the Ca(2+)-CaMKII-CREB pathway in the hippocampus. In conclusion, TQHXD showed therapeutic effects on a bilateral carotid artery ligation-induced vascular dementia model, through the up-regulation of calcium signalling pathways. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Attenuated flow‐induced dilatation of middle cerebral arteries is related to increased vascular oxidative stress in rats on a short‐term high salt diet

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Cosic, Anita; Jukic, Ivana; Stupin, Ana; Mihalj, Martina; Mihaljevic, Zrinka; Novak, Sanja; Vukovic, Rosemary

2016-01-01

Key points Recent studies have shown that high salt (HS) intake leads to endothelial dysfunction and impaired vascular reactivity in different vascular beds in both animal and human models, due to increased oxidative stress.The objective of this study was to assess vascular response to flow‐induced dilatation (FID) and to elucidate the role of vascular oxidative stress/antioxidative capacity in middle cerebral arteries (MCAs) of HS‐fed rats in vitro.The novelty of this study is in demonstrating impaired flow‐induced dilatation of MCAs and down‐regulation of vascular antioxidant genes with HS intake, leading to increased levels of oxidative stress in blood vessels and peripheral lymph organs, which together contribute to impaired FID.In addition, results show increased oxidative stress in leukocytes of peripheral lymph organs, suggesting the occurrence of inflammatory processes due to HS intake.Recirculation of leukocytes might additionally increase vascular oxidative stress in vivo. Abstract The aim of this study was to determine flow‐induced dilatation (FID) and the role of oxidative stress/antioxidative capacity in isolated, pressurized middle cerebral arteries (MCAs) of high salt (HS)‐fed rats. Healthy male Sprague‐Dawley rats (11 weeks old) were fed low salt (0.4% NaCl; LS group) or high salt (4% NaCl; HS group) diets for 1 week. Reactivity of MCAs in response to stepwise increases in pressure gradient (Δ10–Δ100 mmHg) was determined in the absence or presence of the superoxide dismutase (SOD) mimetic TEMPOL and/or the nitric oxide synthases (NOS) inhibitor N ω‐nitro‐l‐arginine methyl ester (l‐name). mRNA levels of antioxidative enzymes, NAPDH‐oxidase components, inducible (iNOS) and endothelial nitric oxide synthases (eNOS) were determined by quantitative real‐time PCR. Blood pressure (BP), antioxidant enzymes activity, oxidative stress in peripheral leukocytes, lipid peroxidation products and the antioxidant capacity of plasma

Data on the effects of losartan on protein expression, vascular reactivity and antioxidant capacity in the aorta of ethanol-treated rats

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Carla S. Ceron

2017-04-01

Full Text Available We describe the effects of losartan, a selective AT1 receptor antagonist on the alterations induced by treatment with ethanol in the rat aorta. The data shown here are related to the article entitled “Angiotensin type 1 receptor mediates chronic ethanol consumption-induced hypertension and vascular oxidative stress” (P. Passaglia, C.S. Ceron, A.S. Mecawi, J. Antunes-Rodrigues, E.B. Coelho, C.R. Tirapelli, 2015 [1]. Here we include new data on the protective effect of losartan against ethanol-induced oxidative stress. Male Wistar rats treated for 2 weeks with ethanol (20%, vol./vol. exhibited increased aortic production of reactive oxygen species (ROS and losartan (10 mg/kg/day; p.o. gavage prevented this response. Ethanol did not alter the expression of eNOS in the rat aorta. Losartan prevented ethanol-induced increase in the aortic expression of nNOS. Neither ethanol nor losartan affected superoxide dismutase (SOD or catalase (CAT activities in the rat aorta. Treatment with ethanol increased the contraction induced by phenylephrine in both endothelium-intact and endothelium-denuded aortas and these responses were prevented by losartan. Conversely, neither ethanol nor losartan affected the endothelium-dependent relaxation induced by acetylcholine.

Comparison of mesencephalic free-floating tissue culture grafts and cell suspension grafts in the 6-hydroxydopamine-lesioned rat

DEFF Research Database (Denmark)

Meyer, Morten; Widmer, H R; Wagner, B

1998-01-01

of grafted dopaminergic neurons and to correlate that with the behavioral effects. Additional cultures and acutely prepared explants were also fixed and stored for histological investigation in order to estimate the loss of dopaminergic neurons in culture and after transplantation. Similar behavioral...... numbers of TH-immunoreactive (TH-ir) neurons in grafts of cultured tissue (775 +/- 98, mean +/- SEM) and grafts of fresh, dissociated cell suspension (806 +/- 105, mean +/- SEM). Cell counts in fresh explants, 7-day-old cultures, and grafted cultures revealed a 68.2% loss of TH-ir cells 7 days after......Ventral mesencephalon (VM) of fetal rat and human origin grown as free-floating roller-tube (FFRT) cultures can survive subsequent grafting to the adult rat striatum. To further explore the functional efficacy of such grafts, embryonic day 13 ventral mesencephalic tissue was grafted either after 7...

Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

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Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

2017-08-17

Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

Changes in expression of a functional Gi protein in cultured rat heart cells

International Nuclear Information System (INIS)

Allen, I.S.; Gaa, S.T.; Rogers, T.B.

1988-01-01

The muscarinic cholinergic agonist, carbachol, and pertussis toxin were used to examine the functional status of the guanine nucleotide-binding protein that inhibits adenylate cyclase (G i ) in cultured neonatal rat heart myocytes. The isoproterenol stimulation of adenylate cyclase activity in myocyte membranes and adenosine 3',5'-cyclic monophosphate (cAMP) accumulation in intact cells (4 days in culture) were insensitive to carbachol. However, in cells cultured for 11 days, carbachol inhibited isoproterenol-stimulated cAMP accumulation by 30%. Angiotensin II (ANG II) was also found to inhibit isoproterenol-stimulated cAMP accumulation in day 11 cells in a dose-dependent manner. Pertussis toxin treatment reversed the inhibitory effects of both ANG II and carbachol, suggesting a role for G i in the process. Carbachol binding to membranes from day 4 cells was relatively insensitive to guanine nucleotides when compared with binding to membranes from day 11 or adult cells. Furthermore, pertussis toxin-mediated 32 P incorporation into a 39- to 41-kDa substrate in day 11 membranes was increased 3.2-fold over that measured in day 4 membranes. These findings support the view that, although G i is expressed, it is nonfunctional in 4-day-old cultured neonatal rat heart myocytes and acquisition of functional G i is dependent on culture conditions. Furthermore, the ANG II receptor can couple to G i in heart

Effects of exercise training on stress-induced vascular reactivity alterations: role of nitric oxide and prostanoids

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Thiago Bruder-Nascimento

2015-06-01

Full Text Available Background: Physical exercise may modify biologic stress responses. Objective: To investigate the impact of exercise training on vascular alterations induced by acute stress, focusing on nitric oxide and cyclooxygenase pathways. Method: Wistar rats were separated into: sedentary, trained (60-min swimming, 5 days/week during 8 weeks, carrying a 5% body-weight load, stressed (2 h-immobilization, and trained/stressed. Response curves for noradrenaline, in the absence and presence of L-NAME or indomethacin, were obtained in intact and denuded aortas (n=7-10. Results: None of the procedures altered the denuded aorta reactivity. Intact aortas from stressed, trained, and trained/stressed rats showed similar reduction in noradrenaline maximal responses (sedentary 3.54±0.15, stressed 2.80±0.10*, trained 2.82±0.11*, trained/stressed 2.97± 0.21*, *P<0.05 relate to sedentary. Endothelium removal and L-NAME abolished this hyporeactivity in all experimental groups, except in trained/stressed rats that showed a partial aorta reactivity recovery in L-NAME presence (L-NAME: sedentary 5.23±0,26#, stressed 5.55±0.38#, trained 5.28±0.30#, trained/stressed 4.42±0.41, #P<0.05 related to trained/stressed. Indomethacin determined a decrease in sensitivity (EC50 in intact aortas of trained rats without abolishing the aortal hyporeactivity in trained, stressed, and trained/stressed rats. Conclusions: Exercise-induced vascular adaptive response involved an increase in endothelial vasodilator prostaglandins and nitric oxide. Stress-induced vascular adaptive response involved an increase in endothelial nitric oxide. Beside the involvement of the endothelial nitric oxide pathway, the vascular response of trained/stressed rats involved an additional mechanism yet to be elucidated. These findings advance on the understanding of the vascular processes after exercise and stress alone and in combination.

Induction of peroxisomal beta-oxidation by a microbial catabolite of cholic acid in rat liver and cultured rat hepatocytes.

Science.gov (United States)

Nishimaki-Mogami, T; Takahashi, A; Toyoda, K; Hayashi, Y

1993-01-01

The capability of (4R)-4-(2,3,4,6,6a beta,7,8,9,9a alpha,9b beta-decahydro-6a beta-methyl-3-oxo-1H-cyclopental[f]quinolin-7 beta-yl)valeric acid (DCQVA), a catabolite of cholic acid produced by enterobacteria, to induce peroxisome proliferation in vivo and in vitro was studied. Rats given 0.3% DCQVA in the diet for 2 weeks showed marked increases in peroxisomal beta-oxidation, mitochondrial 2,4-dienoyl-CoA reductase and microsomal laurate omega-oxidation activities in the liver compared with control rats given the diet without DCQVA. Cultured rat hepatocytes treated with DCQVA for 72 h also exhibited greatly enhanced beta-oxidation activity. The increased activity was concentration-dependent and the effective concentrations were comparable with those of clofibric acid that produced the same degree of induction in the assay. The results demonstrate that DCQVA is a potent peroxisome proliferator that occurs naturally in rat intestine. PMID:8216219

Tissue culture of osteogenic sarcoma in rats, induced by radioactive phosphorus P-32 and the effect of the anti-cancerous agents on these tumor cells under tissue culture

International Nuclear Information System (INIS)

Osaka, Shunzo

1976-01-01

Small pieces of osteogenic sarcoma, induced into albino rats of the C.F. Wistar strain by injection of radioactive phosphorus 32 P, were cultured in mixtures of Eagle's minimum essential medium and 20% calf serum. The tumor cells cultured in this way were transplanted into the subcutaneous tissue or the intraabdominal cavity to healthy albino rats. The effect of the anticancerous agents was evaluated by the decrease of nucleic acid composition in these cultured tumor cells. As anti-cancerous agents, cyclophosphamide (CPA), mitomycin C(MMC), and 5-fluorouracil(5-FU) were put into contact with the tumor cells in cultures for two hours under the following dilutions: CPA; 10 -6 , 10 -5 , 10 -4 g/ml. MMC; 2 x 10 -8 , 2 x 10 -7 , 2 x 10 -6 g/ml. 5-FU; 2 x 10 -6 , 2 x 10 -5 , 2 x 10 -4 g/ml. The results are as follows: Three of the seven osteogenic sarcomas in rats were successfully cultured, one of them through more than eighteen generations. After about five hundred thousand cultured cells had been transplanted into the subcutaneous tissues or abdominal cavities of rats, tumors grew in all of them. The histological findings of the tumors in the second generation were quite similar to those of the original tumor. The same process was repeated three times and the tumor showed histogical findings similar to those of the original ones. The capability of nucleic acid synthesis in these cells was decreased at twenty fours after CPA contact and at forty eight hours after MMC. (J.P.N.)

Comparative effects of sodium channel blockers in short term rat whole embryo culture

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Nilsson, Mats F, E-mail: Mats.Nilsson@farmbio.uu.se [Department of Pharmaceutical Biosciences, Uppsala University (Sweden); Sköld, Anna-Carin; Ericson, Ann-Christin; Annas, Anita; Villar, Rodrigo Palma [AstraZeneca R and D Södertälje (Sweden); Cebers, Gvido [AstraZeneca R and D, iMed, 141 Portland Street, Cambridge, MA 02139 (United States); Hellmold, Heike; Gustafson, Anne-Lee [AstraZeneca R and D Södertälje (Sweden); Webster, William S [Department of Anatomy and Histology, University of Sydney (Australia)

2013-10-15

This study was undertaken to examine the effect on the rat embryonic heart of two experimental drugs (AZA and AZB) which are known to block the sodium channel Nav1.5, the hERG potassium channel and the L-type calcium channel. The sodium channel blockers bupivacaine, lidocaine, and the L-type calcium channel blocker nifedipine were used as reference substances. The experimental model was the gestational day (GD) 13 rat embryo cultured in vitro. In this model the embryonic heart activity can be directly observed, recorded and analyzed using computer assisted image analysis as it responds to the addition of test drugs. The effect on the heart was studied for a range of concentrations and for a duration up to 3 h. The results showed that AZA and AZB caused a concentration-dependent bradycardia of the embryonic heart and at high concentrations heart block. These effects were reversible on washout. In terms of potency to cause bradycardia the compounds were ranked AZB > bupivacaine > AZA > lidocaine > nifedipine. Comparison with results from previous studies with more specific ion channel blockers suggests that the primary effect of AZA and AZB was sodium channel blockage. The study shows that the short-term rat whole embryo culture (WEC) is a suitable system to detect substances hazardous to the embryonic heart. - Highlights: • Study of the effect of sodium channel blocking drugs on embryonic heart function • We used a modified method rat whole embryo culture with image analysis. • The drugs tested caused a concentration dependent bradycardia and heart block. • The effect of drugs acting on multiple ion channels is difficult to predict. • This method may be used to detect cardiotoxicity in prenatal development.

Comparative effects of sodium channel blockers in short term rat whole embryo culture

International Nuclear Information System (INIS)

Nilsson, Mats F; Sköld, Anna-Carin; Ericson, Ann-Christin; Annas, Anita; Villar, Rodrigo Palma; Cebers, Gvido; Hellmold, Heike; Gustafson, Anne-Lee; Webster, William S

2013-01-01

This study was undertaken to examine the effect on the rat embryonic heart of two experimental drugs (AZA and AZB) which are known to block the sodium channel Nav1.5, the hERG potassium channel and the L-type calcium channel. The sodium channel blockers bupivacaine, lidocaine, and the L-type calcium channel blocker nifedipine were used as reference substances. The experimental model was the gestational day (GD) 13 rat embryo cultured in vitro. In this model the embryonic heart activity can be directly observed, recorded and analyzed using computer assisted image analysis as it responds to the addition of test drugs. The effect on the heart was studied for a range of concentrations and for a duration up to 3 h. The results showed that AZA and AZB caused a concentration-dependent bradycardia of the embryonic heart and at high concentrations heart block. These effects were reversible on washout. In terms of potency to cause bradycardia the compounds were ranked AZB > bupivacaine > AZA > lidocaine > nifedipine. Comparison with results from previous studies with more specific ion channel blockers suggests that the primary effect of AZA and AZB was sodium channel blockage. The study shows that the short-term rat whole embryo culture (WEC) is a suitable system to detect substances hazardous to the embryonic heart. - Highlights: • Study of the effect of sodium channel blocking drugs on embryonic heart function • We used a modified method rat whole embryo culture with image analysis. • The drugs tested caused a concentration dependent bradycardia and heart block. • The effect of drugs acting on multiple ion channels is difficult to predict. • This method may be used to detect cardiotoxicity in prenatal development

EFFECT OF AURICULAR ACUPUNCTURE ON THE LEARNING AND MEMORY AND bcl-2 EXPRESSION IN VASCULAR DEMENTIA RATS

Institute of Scientific and Technical Information of China (English)

ZHANG Xuezhao; XIAO Maolei; SUN Guojie

2002-01-01

Objective: To study the effect of auricular acupuncture on dysmnesia and the relationship between the memory improvement and bcl-2 protein expression in vascular dementia (VD) rats. Methods: Forty Wistar rats were randomized into control group, VD group, acupuncture+ VD group and pseudo-operation group, with 10 cases in each group. Rat VD model was established by using 4-vessel occlusion method. Otopoint "Nao"-point and "Shen"(MA-SC)were punctured, once daily continuously for 15 days. The rats' memory capability was tested with Y-maze method and bcl-2 expression of the brain tissues displayed by immunohistochemical method and measured using MIAS-2000 Image Analyzer. Results: Results showed that the scores of control group, VD group and acupuncture+ VD group before operation were 5.68±1.29, 6.07±1.67 and 5.86±1.74 respectively, while following auricular acupuncture treatment,the scores of the 3 groups were 5.81±1.51, 18.06±2.68 and 8.31 ± 1.85 separately, suggesting that the VD rat's learning and memory abilities in acupuncture+ VD group were raised apparently in comparison with those of VD group (P ＜ 0.01 ). In control, VD and acupuncture+VD group, bcl-2 immuno-reaction positive neurons in CA1 area of the hippocampus were 14.31 ± 4.87, 28.67 ± 5.63 and 65.74 ± 8.19 respectively, displaying that the improvement of learning and memory abilities caused by auricular acupuncture treatment may be related to the up-regulation of bcl-2expression (an inhibitory gene of apoptosis). In comparison with control group, the loss of neurons in the pyramidal cell layer of the hippocampal CA1 area of VD group was more severe, while that of acupuncture group was markedly lighter. Conclusion: Auricular acupuncture of otopoint "Nao"-point and "Shen" (MA-SC) can raise the learning and memory abilities of VD rats, which may be realized by its inhibitory effect on apoptosis and the protection action on ischemic hippocampal neurons.

Effects of heavy-ion radiation on the brain vascular system

International Nuclear Information System (INIS)

Yang, T.C.; Craise, L.M.; Tobias, C.A.

1985-01-01

In the laboratory, the authors have been studying the effects of heavy-ion radiation on the vascular system, using neonatal rats as a model system. They investigated the response of the brain vascular system to ionizing radiation and found that distinct petechial hemorrhages developed in the cerebral cortex within a few hours after irradiation, reached a maximum after about 13 to 24 hours, and then decreased exponentially with time. No brain hemorrhage was found in neonatal rats 12 days after irradiation. Heavy ions induce more hemorrhages than x rays for a given dose, and the RBE for 670-MeV/u neon particles ranges from about 2.0 for low doses to about 1.4 for high doses

Evaluation of castor oil-based polyurethane membranes in rat bone-marrow cell culture.

Science.gov (United States)

Cerejo, Sofia de Amorim; Rahal, Sheila Canevese; Lima Neto, João Ferreira de; Voorwald, Fabiana Azevedo; Alvarenga, Fernanda da Cruz Landim e

2011-10-01

To evaluate three methods to isolate rats MSCs and to analyze the potential of a castor oil polyurethane base membrane as a scaffold for MSCs. Four male Wistar rats, aged 20-30 days were used. Bone marrow aspirates from femur and tibia were harvested using DMEM high glucose and heparin. The cell culture was performed in three different ways: direct culture and two types of density gradients. After 15 days, was made the 1st passage and analyzed cell viability with markers Hoerscht 33342 and propidium iodide. The MSCs were characterized by surface markers with the aid of flow cytometry. After this, three types of castor oil polyurethane membranes associated with the MSCs were kept on the 6-well plate for 5 days and were analyzed by optical microscopy to confirm cell aggregation and growth. Separation procedures 1 and 2 allowed adequate isolation of MSCs and favored cell growth with the passage being carried out at 70% confluence after 15 days in culture. The cells could not be isolated using procedure 3. When the 3 castor oil polyurethane membrane types were compared it was possible to observe that the growth of MSCs was around 80% in membrane type 3, 20% in type 2, and 10% in type 1. Both Ficoll-Hypaque densities allow isolation of rat MSCs, and especially castor oil-based membrane type 3 may be used as a scaffold for MSCs.

The effects of vascularized tissue transfer on re-irradiation

International Nuclear Information System (INIS)

Narayan, K.; Ashton, M.W.; Taylor, G.I.

1996-01-01

Purpose: Nowadays, radical re-irradiation of locally recurrent squamous cell carcinoma is being increasingly tried. The process usually involves some form of surgical excision and vascularized tissue transfer followed by re-irradiation. The aim of this study was to examine the extent of protection from the effects of re-irradiation provided by vascularized tissue transfer. Methods and Materials: One hundred Sprague Dawley rats had their left thighs irradiated to a total dose of 72Gy in 8 fractions, one fraction per day, 5 days per week. The rats were then divided into two groups: At 4 months, one half of the rats had 50% of their quadriceps musculature excised and replaced with a vascularized non-irradiated rectus abdominous myocutaneous flap. The other group served as the control. Six months following the initial radiotherapy all rats were then re-irradiated with either 75 or 90% of the original dose. Incidence of necrosis and the extent of necrosis was measured. Microvasculature of control, transplanted muscle and recipient site was studied by micro-corrosion cast technique and histology of cast specimen. tissues were sampled at pre-irradiation and at 2, 6 and 12 months post re-irradiation. Microvascular surface area was measured from the histology of cast specimen. Results: Necrosis in the control group was clinically evident at 6 weeks post re irradiation and by 10 months all rats developed necrosis. Forty per cent of the thigh that received 75% of the original dose on re-irradiation did not develop any necrosis by 13 months. Other groups developed necrosis to variable extents, however a rim of tissue around the graft always survived. The average thickness of surviving tissue was 9mm. (range being 4-25 mm). None of the transferred flap nor re-irradiated recipient quadriceps developed necrosis. Conclusion: 1. Transplanted rectus abdominus myocutaneous flap and undisturbed muscle have similar radiation tolerance. 2. Vascularized myocutaneous flap offers

Cardiac and renal upregulation of Nox2 and NF-κB and repression of Nox4 and Nrf2 in season- and diabetes-mediated models of vascular oxidative stress in guinea-pig and rat.

Science.gov (United States)

Gajos-Draus, Anna; Duda, Monika; Beręsewicz, Andrzej

2017-11-01

The superoxide-forming NADPH oxidase homologues, Nox1, Nox2, and Nox5, seem to mediate the pro-atherosclerotic vascular phenotype. The hydrogen peroxide-forming Nox4 afforded vascular protection, likely via NF-E2-related factor-2 (Nrf2) activation and/or Nox2 downregulation in transgenic mice. We hypothesized that oxidative stress in the intact vasculature involves, aside from the upregulation of the superoxide-forming Noxs, the downregulation of the Nox4/Nrf2 pathway. Guinea-pigs and rats were studied either in winter or in summer, and the streptozotocin diabetic rats in winter. Plasma nitrite, and superoxide production by isolated hearts were measured, while frozen tissues served in biochemical analyses. Summer in both species and diabetes in rats downregulated myocardial Nox4 while reciprocally upregulating Nox2 and Nox5 in guinea-pigs, and Nox2 in rats. Simultaneously, myocardial Nrf2 activity and the expression of the Nrf2-directed heme oxygenase-1 and endothelial NO synthase were reduced while activity of the nuclear factor κ B (NF- κ B) and the expression of NF- κ B-directed inducible NO synthase and the vascular cell adhesion molecule-1 were increased. Cardiac superoxide production was increased while plasma nitrite was decreased reciprocally. Analogous disregulation of Noxs, Nrf2, and NF- κ B, occurred in diabetic rat kidneys. Given the diversity of the experimental settings and the uniform pattern of the responses, we speculate that: (1) chronic vascular oxidative stress is a nonspecific (model-, species-, organ-independent) response involving the induction of Nox2 (and Nox5 in guinea-pigs) and the NF- κ B pathway, and the repression of Nox4 and the Nrf2 pathway; and (2) the systems Nox2-NF- κ B and Nox4-Nrf2 regulate each other negatively. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Generation of primary cultures of bovine brain endothelial cells and setup of cocultures with rat astrocytes

DEFF Research Database (Denmark)

Helms, Hans C; Brodin, Birger

2014-01-01

-brain barrier. The present protocol describes the setup of an in vitro coculture model based on primary cultures of endothelial cells from bovine brain microvessels and primary cultures of rat astrocytes. The model displays a high electrical tightness and expresses blood-brain barrier marker proteins....

Diabetes diminishes the portal-systemic collateral vascular response to vasopressin via vasopressin receptor and Gα proteins regulations in cirrhotic rats.

Directory of Open Access Journals (Sweden)

Jing-Yi Lee

Full Text Available Liver cirrhosis may lead to portal-systemic collateral formation and bleeding. The hemostatic effect is influenced by the response of collateral vessels to vasoconstrictors. Diabetes and glucose also influence vasoresponsiveness, but their net effect on collaterals remains unexplored. This study investigated the impact of diabetes or glucose application on portal-systemic collateral vasoresponsiveness to arginine vasopressin (AVP in cirrhosis. Spraque-Dawley rats with bile duct ligation (BDL-induced cirrhosis received vehicle (citrate buffer or streptozotocin (diabetic, BDL/STZ. The in situ collateral perfusion was done after hemodynamic measurements: Both were perfused with Krebs solution, D-glucose, or D-glucose and NaF, with additional OPC-31260 for the BDL/STZ group. Splenorenal shunt vasopressin receptors and Gα proteins mRNA expressions were evaluated. The survival rate of cirrhotic rats was decreased by STZ injection. The collateral perfusion pressure changes to AVP were lower in STZ-injected groups, which were reversed by OPC-31260 (a V2R antagonist and overcome by NaF (a G protein activator. The splenorenal shunt V2R mRNA expression was increased while Gα proteins mRNA expressions were decreased in BDL/STZ rats compared to BDL rats. The Gαq and Gα11 mRNA expressions also correlated with the maximal perfusion pressure changes to AVP. Diabetes diminished the portal-systemic collateral vascular response to AVP in rats with BDL-induced cirrhosis, probably via V2 receptor up-regulation and Gα proteins down-regulation.

Biomarkers of drug-induced vascular injury

International Nuclear Information System (INIS)

Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

2005-01-01

In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

Comparison of MEK/ERK pathway inhibitors on the upregulation of vascular G-protein coupled receptors in rat cerebral arteries

DEFF Research Database (Denmark)

Sandhu, Hardip; Ansar, Saema; Edvinsson, Lars

2010-01-01

on translational level and increased respective contractions. The prostanoid TP receptor mediated contraction curve was left-wards shifted by organ culture. Organ culture was associated with elevated pERK1/2 in the vascular smooth muscle cells: the MEK1/2 inhibitor U0126 attenuated the endothelin ET(B) receptor......Organ culture is an in vitro method for investigating cellular mechanisms involved in upregulation of vasocontractile G-protein coupled receptors. We hypothesize that mitogen-activated-protein kinase (MEK) and/or extracellular-signal-regulated kinase (ERK) specific inhibitors will attenuate the G......), prostanoid TP receptor, and angiotensin II receptor type 1 and type 2 were investigated. Results were verified by measurement of mRNA with real time PCR and by protein immunohistochemistry. Organ culture induced transcriptional upregulation of endothelin ET(B) receptor and of serotonin 5-HT(1B) receptor...

Comparison of MEK/ERK pathway inhibitors on the upregulation of vascular G-protein coupled receptors in rat cerebral arteries

DEFF Research Database (Denmark)

Sandhu, Hardip; Ansar, Saema; Edvinsson, Lars

2010-01-01

on translational level and increased respective contractions. The prostanoid TP receptor mediated contraction curve was left-wards shifted by organ culture. Organ culture was associated with elevated pERK1/2 in the vascular smooth muscle cells: the MEK1/2 inhibitor U0126 attenuated the endothelin ET(B) receptor...... mediated contraction at post-translational level or by changing the receptor affinities. The serotonin 5-HT(1B) receptor and prostanoid TP receptor mediated contractions were abolished by U0126. Administration of U0126 6h after start of incubation blocked the receptor upregulation. In conclusion, MEK...

MRI and morphological observation in C6 glioma model rats and significance

International Nuclear Information System (INIS)

Zhou Ying; Yuan Bo; Wang Hao; Lu Jin; Yuan Changji; Ma Yue; Tong Dan; Zhang Kun; Gao Feng; Wu Xiaogang

2013-01-01

Objective: To establish stable and reliable rat C6 glioma model, and to perform MRI dynamic observation and pathomorphological observation in model animal brain, and to provide experimental basis for pharmaceutical research on anti-glioma drugs. Methods: The C6 glioma cells were cultured and 20 μL cultural fluid containing 1×10 6 C6 cells was sterotactically implanted into the left caudate nuclei in 10 male Wistar rats, respectively. The changes in the behavior of the rats after implantation were observed and recorded. MRI dynamic scanning was performed in 10 rats 2, 3 and 4 weeks after implantation and the brain tissues were taken for general and pathological examination when the 10 rats were naturally dead. The survival period of tumor-bearing rats was calculated. Results: 2 weeks after implantation the rats showed decreased activities and food intake, fur lackluster, and conjunctival congestion and so on; 3 weeks later, some rats appeared nerve symptoms such as body twitch, body hemiplegy, body distortion, rotation and so on. All the 10 rats died in 8-30 d. The median survival period of the tumor-bearing rats was 18 d, the average survival period was (18.3±7.3) d. The pathological examination showed that the tumor cells were arranged irregularly closely and karyokinesis was easy to see; tumor vascular tissue proliferation and tumor invasive growth into surrounding normal tissues were found. The expression of glial fibrillary acidic protein (GFAP) was positive in the tumors. Conclusion: A stable animal model of intracranial glioma is successfully established by stereotactic implantation of C6 cells into the rat caudate nucleus. The results of MRI dynamic observation and pathohistological observation on the model animal brain tissue. Can provide experimental basis for selecting the appropriate time window to perform the pharmaceutical research on anti-glioma drugs. (authors)

Effect of chlorella and its fractions on blood pressure, cerebral stroke lesions, and life-span in stroke-prone spontaneously hypertensive rats.

Science.gov (United States)

Sansawa, Hiroshi; Takahashi, Masatoshi; Tsuchikura, Satoru; Endo, Hiroshi

2006-12-01

Effects of Chlorella regularis (dried cell powder)--cultured axenically under heterotrophic conditions, and provided as a dietary supplement--and its fractions on the blood pressure, cerebral stroke lesions, and life-span of stroke-prone spontaneously hypertensive rats (SHRSP/Izm) were investigated. When SHRSP were fed on diets with supplemented Chlorella to a commercial diet (Funabashi SP), elevation of blood pressure was significantly lower in the Chlorella groups than in the control group. At 21 wk of feeding, serum total cholesterol was significantly lower in the Chlorella groups than in the control group. Histopathological examination revealed cerebral vascular accidents in the brains of the control group, but those of Chlorella groups showed apparently low incidence compared to the control group. The average life-span of the Chlorella groups were significantly longer than that of the control group (p vascular function of rats.

Feeding Frequency Affects Cultured Rat Pituitary Cells in Low Gravity

Science.gov (United States)

Hymer, W. C.; Grindeland, R. E.; Salada, T.; Cenci, R.; Krishnan, K.; Mukai, C.; Nagaoka, S.

1996-01-01

In this report, we describe the results of a rat pituitary cell culture experiment done on STS-65 in which the effect of cell feeding on the release of the six anterior pituitary hormones was studied. We found complex microgravity related interactions between the frequency of cell feeding and the quantity and quality (i.e. biological activity) of some of the six hormones released in flight. Analyses of growth hormone (GH) released from cells into culture media on different mission days using gel filtration and ion exchange chromatography yielded qualitatively similar results between ground and flight samples. Lack of cell feeding resulted in extensive cell clumping in flight (but not ground) cultures. Vigorous fibroblast growth occurred in both ground and flight cultures fed 4 times. These results are interpreted within the context of autocrine and or paracrine feedback interactions. Finally the payload specialist successfully prepared a fresh trypsin solution in microgravity, detached the cells from their surface and reinserted them back into the culture chamber. These cells reattached and continued to release hormone in microgravity. In summary, this experiment shows that pituitary cells are microgravity sensitive and that coupled operations routinely associated with laboratory cel1 culture can also be accomplished in low gravity.

Lack of direct mitogenic activity of dichloroacetate and trichloroacetate in cultured rat hepatocytes

International Nuclear Information System (INIS)

Walgren, Jennie L.; Kurtz, David T.; McMillan, JoEllyn M.

2005-01-01

Dichloroacetate (DCA) and trichloroacetate (TCA) are hepatocarcinogenic metabolites of the common groundwater contaminant, 1,1,2-trichloroethylene. DCA and TCA have been shown to induce hepatocyte proliferation in vivo, but it is not known if this response is the result of direct mitogenic activity or whether cell replication occurs indirectly in response to tissue injury or inflammation. In this study we used primary cultures of rat hepatocytes, a species susceptible to DCA- but not TCA-induced hepatocarcinogenesis, to determine whether DCA and TCA are direct hepatocyte mitogens. Rat hepatocytes, cultured in growth factor-free medium, were treated with 0.01-1.0 mM DCA or TCA for 10-40 h; cell replication was then assessed by measuring incorporation of 3 H-thymidine into DNA and by cell counts. DCA or TCA treatment did not alter 3 H-thymidine incorporation in the cultured hepatocytes. Although an increase in cell number was not observed, DCA treatment significantly abrogated the normal background cell loss, suggesting an ability to inhibit apoptotic cell death in primary hepatocyte cultures. Furthermore, treatment with DCA synergistically enhanced the mitogenic response to epidermal growth factor. The data indicate that DCA and TCA are not direct mitogens in hepatocyte cultures, which is of interest in view of their ability to stimulate hepatocyte replication in vivo. Nevertheless, the synergistic enhancement of epidermal growth factor-induced hepatocyte replication by DCA is of particular interest and warrants further study

Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

International Nuclear Information System (INIS)

Kyotani, Yoji; Ota, Hiroyo; Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo; Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu; Takasawa, Shin; Kimura, Hiroshi; Uno, Masayuki; Yoshizumi, Masanori

2013-01-01

Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

Energy Technology Data Exchange (ETDEWEB)

Kyotani, Yoji, E-mail: cd147@naramed-u.ac.jp [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Ota, Hiroyo [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Takasawa, Shin [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Kimura, Hiroshi [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Uno, Masayuki [Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Yoshizumi, Masanori [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan)

2013-11-15

Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy

OpenAIRE

Costa, M.; Cerqueira, Mariana Teixeira; Santos, T. C.; Marques, Belém Sampaio; Ludovico, Paula; Marques, A. P.; Pirraco, Rogério P.; Reis, R. L.

2017-01-01

Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditi...

EMMPRIN-mediated induction of uterine and vascular matrix metalloproteinases during pregnancy and in response to estrogen and progesterone.

Science.gov (United States)

Dang, Yiping; Li, Wei; Tran, Victoria; Khalil, Raouf A

2013-09-15

Pregnancy is associated with uteroplacental and vascular remodeling in order to adapt for the growing fetus and the hemodynamic changes in the maternal circulation. We have previously shown upregulation of uterine matrix metalloproteinases (MMPs) during pregnancy. Whether pregnancy-associated changes in MMPs are localized to the uterus or are generalized in feto-placental and maternal circulation is unclear. Also, the mechanisms causing the changes in uteroplacental and vascular MMPs during pregnancy are unclear. MMPs expression, activity and tissue distribution were measured in uterus, placenta and aorta of virgin, mid-pregnant (mid-Preg) and late pregnant (late-Preg) rats. Western blots and gelatin zymography revealed increases in MMP-2 and -9 in uterus and aorta of late-Preg compared with virgin and mid-Preg rats. In contrast, MMP-2 and -9 were decreased in placenta of late-Preg versus mid-Preg rats. Extracellular MMP inducer (EMMPRIN) was increased in uterus and aorta of pregnant rats, but was less in placenta of late-Preg than mid-Preg rats. Prolonged treatment of uterus or aorta of virgin rats with 17β-estradiol and progesterone increased the amount of EMMPRIN, MMP-2 and -9, and the sex hormone-induced increases in MMPs were prevented by EMMPRIN neutralizing antibody. Immunohistochemistry revealed that MMP-2 and -9 and EMMPRIN increased in uterus and aorta of pregnant rats, but decreased in placenta of late-Preg versus mid-Preg rats. Thus pregnancy-associated upregulation of uterine MMPs is paralleled by increased vascular MMPs, and both are mediated by EMMPRIN and induced by estrogen and progesterone, suggesting similar role of MMPs in uterine and vascular tissue remodeling and function during pregnancy. The decreased MMPs and EMMPRIN in placenta of late-Preg rats suggests reduced role of MMPs in feto-placental circulation during late pregnancy. Copyright © 2013 Elsevier Inc. All rights reserved.

Effects of Electroacupuncture on Learning, Memory and Formation System of Free Radicals in Brain Tissues of Vascular Dementia Model Rats

Institute of Scientific and Technical Information of China (English)

王黎; 唐纯志; 赖新生

2004-01-01

In order to observe the regulative effect of electro-acupuncture on the formation system of free radicals in the brain tissues and learning and memory in vascular dementia (VD) model rats, the Morris's water labyrinth was used for testing the learning ability and memory in VD model rats made by 4-vessel occlusion method, and the activities or contents of nitric oxide (NO), NO synthase (NOS), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) were determined. Results showed that the mean escape latency in the electro-acupuncture group was markedly reduced in place test, and the times swam the place of the plate-form in the original plate-form quadrant were significantly more than those in the rest three quadrants in spatia1 probe test as compared with the model group. In the electro-acupuncture group and the nimodipine group the contents of NO and MDA and the activity of NOS were decreased, while the activities of SOD and GSH-Px were increased. It is indicated that electro-acupuncture can modulate the production and clearance of free radicals, and improve the ability of learning and memory of the VD model rats.

Improved vascularization of planar membrane diffusion devices following continuous infusion of vascular endothelial growth factor.

Science.gov (United States)

Trivedi, N; Steil, G M; Colton, C K; Bonner-Weir, S; Weir, G C

2000-01-01

Improving blood vessel formation around an immunobarrier device should improve the survival of the encapsulated tissue. In the present study we investigated the formation of new blood vessels around a planar membrane diffusion device (the Baxter Theracyte System) undergoing a continuous infusion of vascular endothelial growth factor through the membranes and into the surrounding tissue. Each device (20 microl) had both an inner immunoisolation membrane and an outer vascularizing membrane. Human recombinant vascular endothelial growth factor-165 was infused at 100 ng/day (low dose: n = 6) and 500 ng/day (high dose: n = 7) for 10 days into devices implanted s.c. in Sprague-Dawley rats; noninfused devices transplanted for an identical period were used as controls (n = 5). Two days following the termination of VEGF infusion, devices were loaded with 20 microl of Lispro insulin (1 U/kg) and the kinetics of insulin release from the lumen of the device was assessed. Devices were then explanted and the number of blood vessels (capillary and noncapillary) was quantified using morphometry. High-dose vascular endothelial growth factor infusion resulted in two- to threefold more blood vessels around the device than that obtained with the noninfused devices and devices infused with low-dose vascular endothelial growth factor. This increase in the number of blood vessels was accompanied by a modest increase in insulin diffusion from the device in the high-dose vascular endothelial growth factor infusion group. We conclude that vascular endothelial growth factor can be used to improve blood vessel formation adjacent to planar membrane diffusion devices.

Involvement of Inflammation and Adverse Vascular Remodelling in the Blood Pressure Raising Effect of Repeatedly Heated Palm Oil in Rats

Directory of Open Access Journals (Sweden)

Chun-Yi Ng

2012-01-01

Full Text Available Oil thermoxidation during deep frying generates harmful oxidative free radicals that induce inflammation and increase the risk of hypertension. This study aimed to investigate the effect of repeatedly heated palm oil on blood pressure, aortic morphometry, and vascular cell adhesion molecule-1 (VCAM-1 expression in rats. Male Sprague-Dawley rats were divided into five groups: control, fresh palm oil (FPO, one-time-heated palm oil (1HPO, five-time-heated palm oil (5HPO, or ten-time-heated palm oil (10HPO. Feeding duration was six months. Blood pressure was measured at baseline and monthly using tail-cuff method. After six months, the rats were sacrificed and the aortic arches were dissected for morphometric and immunohistochemical analyses. FPO group showed significantly lower blood pressure than all other groups. Blood pressure was increased significantly in 5HPO and 10HPO groups. The aortae of 5HPO and 10HPO groups showed significantly increased thickness and area of intima-media, circumferential wall tension, and VCAM-1 than other groups. Elastic lamellae were disorganised and fragmented in 5HPO- and 10HPO-treated rats. VCAM-1 expression showed a significant positive correlation with blood pressure. In conclusion, prolonged consumption of repeatedly heated palm oil causes blood pressure elevation, adverse remodelling, and increased VCAM-1, which suggests a possible involvement of inflammation.

Rat glomerular epithelial cells in culture. Parietal or visceral epithelial origin

International Nuclear Information System (INIS)

Norgaard, J.O.

1987-01-01

Isolated glomeruli from rats were explanted under standard culture conditions and outgrowths were studied by light and electron microscopy in order to identify the cells. Rat glomerular samples contained 20 to 30% structurally well-preserved encapsulated glomeruli which had a large rate of attachment to the substrate and very constantly gave rise to cellular outgrowth. In order to label cells from which outgrowth originated the glomerular incorporation of [ 3 H]thymidine was studied in the preattachment phase. By light and electron microscope autoradiograph it was demonstrated that label was located only over visceral and parietal epithelial cells during the first 3 days of culture. Incorporation of [ 3 H]thymidine was seen in mesangial cells after 5 days, i.e., after the glomeruli had attached to the culture vessels and the initial outgrowth had appeared. Consequently the first cells to grow out were of epithelial origin. Glomeruli were then incubated with [ 3 H]thymidine for the first 2 1/2 days of culture in order to label the epithelial cells, then were allowed to attach to the substrate and induce cell outgrowth. By light microscope autoradiography performed with the outgrowths in situ two types of cells with labeled nuclei were seen: (a) a small, polyhedral ciliated cell which grew in colonies where the cells were joined by junctional complexes (type I), and (b) a second very large, often multinucleated cell (type II). Based on the structural resemblance with their counterparts in situ and on comparisons with positively identified visceral epithelial cells in outgrowths from other species it is suggested that type I cells are derived from the parietal epithelium of Bowman's capsule and type II cells from the visceral epithelium

Ionic currents and charge movements in organ-cultured rat skeletal muscle.

Science.gov (United States)

Hollingworth, S; Marshall, M W; Robson, E

1984-12-01

The middle of the fibre voltage-clamp technique was used to measure ionic currents and non-linear charge movements in intact, organ-cultured (in vitro denervated) mammalian fast-twitch (rat extensor digitorum longus) muscle fibres. Muscle fibres organ cultured for 4 days can be used as electrophysiological and morphological models for muscles in vivo denervated for the same length of time. Sodium currents in organ-cultured muscle fibres are similar to innervated fibres except that in the temperature range 0-20 degrees C (a) in the steady state, the voltage distribution of inactivation in cultured fibres is shifted negatively some 20 mV; (b) at the same temperature and membrane potential, the time constant of inactivation in cultured fibres is about twice that of innervated fibres. Potassium currents in innervated and cultured fibres at 15 degrees C can be fitted with the Hodgkin-Huxley n variable raised to the second power. Despite the large range we would estimate that the maximum value of the steady-state potassium conductance of cultured fibres is about one-half that of innervated fibres. The estimated maximum amount of charge moved in cultured fibre is about one-third that in innervated fibres. Compared to innervated fibres, culturing doubles the kinetics of the decay phase of charge movement. The possibility of a negative shift of the voltage distribution of charge movements in cultured fibres is discussed.

Effects of hyperthyroidism on expression of vascular endothelial growth factor (VEGF and apoptosis in fetal adrenal glands

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T. Karaca

2015-11-01

Full Text Available This study investigated the expression of vascular endothelial growth factor (VEGF, vascular density, and apoptosis in fetal rat adrenal glands with hyperthyroidism in late gestation. Twelve mature female Wistar albino rats with the same biological and physiological features were used for this study. Rats were divided into two groups: control and hyperthyroidism. Hyperthyroidism was induced by daily subcutaneous injections of L-thyroxine (250 μg/kg before pregnancy for 21 days and during pregnancy. Rats in the control and hyperthyroidism groups were caged according to the number of male rats. Zero day of pregnancy (Day 0 was indicated when the animals were observed to have microscopic sperm in vaginal smears. Pregnant rats were sacrificed on the 20th day of pregnancy; blood from each animal was collected to determine the concentrations of maternal adrenocorticotropic hormone and thyroxine. Rat fetuses were then quickly removed from the uterus, and the adrenal glands of the fetuses were dissected. VEGF expression, vascular density, and apoptosis were analyzed in fetal rat adrenal glands. Maternal serum levels of the adrenocorticotropic hormone and free thyroxine were significantly higher in the hyperthyroidism group than in the control group. Immunohistochemistry revealed that the number of VEGF positive cells and vessel density significantly increased in the hyperthyroidism rat fetal adrenal group compared with the control group. Hyperthyroidism did not change the fetal and placental weights and the number of fetuses. This study demonstrates that hyperthyroidism may have an effect on the development of rat adrenal glands mediated by VEGF expression, angiogenesis, and apoptosis. 

Effects of hyperthyroidism on expression of vascular endothelial growth factor (VEGF) and apoptosis in fetal adrenal glands.

Science.gov (United States)

Karaca, T; Hulya Uz, Y; Karabacak, R; Karaboga, I; Demirtas, S; Cagatay Cicek, A

2015-11-26

This study investigated the expression of vascular endothelial growth factor (VEGF), vascular density, and apoptosis in fetal rat adrenal glands with hyperthyroidism in late gestation. Twelve mature female Wistar albino rats with the same biological and physiological features were used for this study. Rats were divided into two groups: control and hyperthyroidism. Hyperthyroidism was induced by daily subcutaneous injections of L-thyroxine (250 μg/kg) before pregnancy for 21 days and during pregnancy. Rats in the control and hyperthyroidism groups were caged according to the number of male rats. Zero day of pregnancy (Day 0) was indicated when the animals were observed to have microscopic sperm in vaginal smears. Pregnant rats were sacrificed on the 20th day of pregnancy; blood from each animal was collected to determine the concentrations of maternal adrenocorticotropic hormone and thyroxine. Rat fetuses were then quickly removed from the uterus, and the adrenal glands of the fetuses were dissected. VEGF expression, vascular density, and apoptosis were analyzed in fetal rat adrenal glands. Maternal serum levels of the adrenocorticotropic hormone and free thyroxine were significantly higher in the hyperthyroidism group than in the control group. Immunohistochemistry revealed that the number of VEGF positive cells and vessel density significantly increased in the hyperthyroidism rat fetal adrenal group compared with the control group. Hyperthyroidism did not change the fetal and placental weights and the number of fetuses. This study demonstrates that hyperthyroidism may have an effect on the development of rat adrenal glands mediated by VEGF expression, angiogenesis, and apoptosis.

Collagen-embedded hydroxylapatite-beta-tricalcium phosphate-silicon dioxide bone substitute granules assist rapid vascularization and promote cell growth

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Ghanaati, Shahram M; Thimm, Benjamin W; Unger, Ronald E; Orth, Carina; Barbeck, Mike; Kirkpatrick, C James [Institute of Pathology, Johannes Gutenberg-University Mainz, Langenbeckstr.1, 55101 Mainz (Germany); Kohler, Thomas; Mueller, Ralph, E-mail: ghanaati@uni-mainz.d [Institute for Biomechanics, ETH Zuerich, Wolfgang-Pauli-Str.10, 8093 Zuerich (Switzerland)

2010-04-15

In the present study we assessed the biocompatibility in vitro and in vivo of a low-temperature sol-gel-manufactured SiO{sub 2}-based bone graft substitute. Human primary osteoblasts and the osteoblastic cell line, MG63, cultured on the SiO{sub 2} biomatrix in monoculture retained their osteoblastic morphology and cellular functionality in vitro. The effect of the biomaterial in vivo and its vascularization potential was tested subcutaneously in Wistar rats and demonstrated both rapid vascularization and good integration within the peri-implant tissue. Scaffold degradation was progressive during the first month after implantation, with tartrate-resistant acid phosphatase-positive macrophages being present and promoting scaffold degradation from an early stage. This manuscript describes successful osteoblastic growth promotion in vitro and a promising biomaterial integration and vasculogenesis in vivo for a possible therapeutic application of this biomatrix in future clinical studies.

Mathematical Modeling of Neuro-Vascular Coupling in Rat Cerebellum

DEFF Research Database (Denmark)

Rasmussen, Tina

Activity in the neurons called climbing fibers causes blood flow changes. But the physiological mechanisms which mediate the coupling are not well understood. This PhD thesis investigates the mechanisms of neuro-vascular coupling by means of mathematical methods. In experiments, the extracellularly...... measured field potential is used as an indicator of neuronal activity, and the cortical blood flow is measured by means of laser-Doppler flowmetry. Using system identification methods, these measurements have been used to construct and validate parametric mathematical models of the neuro-vascular system...

Human bone marrow mesenchymal stem cells for retinal vascular injury.

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Wang, Jin-Da; An, Ying; Zhang, Jing-Shang; Wan, Xiu-Hua; Jonas, Jost B; Xu, Liang; Zhang, Wei

2017-09-01

To examine the potential of intravitreally implanted human bone marrow-derived mesenchymal stem cells (BMSCs) to affect vascular repair and the blood-retina barrier in mice and rats with oxygen-induced retinopathy, diabetic retinopathy or retinal ischaemia-reperfusion damage. Three study groups (oxygen-induced retinopathy group: 18 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received BMSCs injected intravitreally. Control groups (oxygen-induced retinopathy group: 12 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received an intravitreal injection of phosphate-buffered saline. We applied immunohistological techniques to measure retinal vascularization, spectroscopic measurements of intraretinally extravasated fluorescein-conjugated dextran to quantify the blood-retina barrier breakdown, and histomorphometry to assess retinal thickness and retinal ganglion cell count. In the oxygen-induced retinopathy model, the study group with intravitreally injected BMSCs as compared with the control group showed a significantly (p = 0.001) smaller area of retinal neovascularization. In the diabetic retinopathy model, study group and control group did not differ significantly in the amount of intraretinally extravasated dextran. In the retinal ischaemia-reperfusion model, on the 7th day after retina injury, the retina was significantly thicker in the study group than in the control group (p = 0.02), with no significant difference in the retinal ganglion cell count (p = 0.36). Intravitreally implanted human BMSCs were associated with a reduced retinal neovascularization in the oxygen-induced retinopathy model and with a potentially cell preserving effect in the retinal ischaemia-reperfusion model. Intravitreal BMSCs may be of potential interest for the therapy of retinal vascular disorders. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley

Increased Pathogen Identification in Vascular Graft Infections by the Combined Use of Tissue Cultures and 16S rRNA Gene Polymerase Chain Reaction

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Evelyne Ajdler-Schaeffler

2018-06-01

Full Text Available Background: Vascular graft infections (VGI are difficult to diagnose and treat, and despite redo surgery combined with antimicrobial treatment, outcomes are often poor. VGI diagnosis is based on a combination of clinical, radiological, laboratory and microbiological criteria. However, as many of the VGI patients are already under antimicrobial treatment at the time of redo surgery, microbiological identification is often difficult and bacterial cultures often remain negative rendering targeted treatment impossible. We aimed to assess the benefit of 16S rRNA gene polymerase chain reaction (broad-range PCR for better microbiological identification in patients with VGI.Methods: We prospectively analyzed the clinical, microbiological, and treatment data of patients enrolled in the observational Vascular Graft Cohort Study (VASGRA, University Hospital Zurich, Switzerland. The routine diagnostic work-up involved microbiological cultures of minced tissue samples, and the use of molecular techniques in parallel. Patient-related and microbiological data were assessed in descriptive analyses, and we calculated sensitivity, specificity, negative and positive predictive value for broad-range 16S rRNA gene PCR versus culture (considered as gold standard.Results: We investigated 60 patients (median age 66 years (Interquartile range [IQR] 59–75 with confirmed VGI between May 2013 and July 2017. The prevalence of antimicrobial pretreatment at the time of sampling was high [91%; median days of antibiotics 7 days (IQR 1–18]. We investigated 226 microbiological specimens. Thereof, 176 (78% were culture-negative and 50 (22% were culture-positive. There was a concordance of 70% (158/226 between conventional culture and broad-range PCR (sensitivity 58% (95% CI 43–72; specificity 74% (67–80%. Among the group of 176 culture-negative specimens, 46 specimens were broad-range PCR-positive resulting in identification of overall 69 species. Among the culture and

Fructose intake exacerbates the contractile response elicited by norepinephrine in mesenteric vascular bed of rats via increased endothelial prostanoids.

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Sousa, Glauciene J; Oliveira, Phablo Wendell C; Nogueira, Breno V; Melo, Antônio F; Faria, Thaís de Oliveira; Meira, Eduardo Frizera; Mill, José G; Bissoli, Nazaré S; Baldo, Marcelo P

2017-10-01

Chronic fructose intake induces major cardiovascular and metabolic disturbances and is associated with the development of hypertension due to changes in vascular function. We hypothesized that high fructose intake for 6 weeks would cause metabolic syndrome and lead to initial vascular dysfunction. Male Wistar rats were assigned to receive fructose (FRU, 10%) or drinking water (CON) for 6 weeks. Systolic blood pressure was evaluated by tail plethysmography. Fasting glucose, insulin and glucose tolerance were measured at the end of the follow-up. Mesenteric vascular bed reactivity was tested before and after pharmacological blockade. Western blot analysis was performed for iNOS, eNOS, Nox2 and COX-2. DHE staining was used for vascular superoxide anion detection. Vessel structure was evaluated by optical and electronic microscopy. Fructose intake did not alter blood pressure, but did increase visceral fat deposition and fasting glucose as well as impair insulin and glucose tolerance. Fructose increased NE-induced vasoconstriction compared with CON, and this difference was abrogated by indomethacin perfusion as well as endothelium removal. ACh-induced relaxation was preserved, and the NO modulation tested after L-NAME perfusion was similar between groups. SNP-induced relaxation was not altered. Inducible NOS was increased; however, there were no changes in eNOS, Nox2 or COX-2 protein expression. Basal or stimulated superoxide anion production was not changed by fructose intake. In conclusion, high fructose intake increased NE-induced vasoconstriction through the endothelial prostanoids even in the presence of a preserved endothelium-mediated relaxation. No major changes in vessel structure were detected. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of epidermal growth factor (EGF) and hydrocortisone on the co-culture of mature adipocytes and endothelial cells for vascularized adipose tissue engineering.

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Huber, Birgit; Czaja, Alina Maria; Kluger, Petra Juliane

2016-05-01

The composition of vascularized adipose tissue is still an ongoing challenge as no culture medium is available to supply adipocytes and endothelial cells appropriately. Endothelial cell medium is typically supplemented with epidermal growth factor (EGF) as well as hydrocortisone (HC). The effect of EGF on adipocytes is discussed controversially. Some studies say it inhibits adipocyte differentiation while others reported of improved adipocyte lipogenesis. HC is known to have lipolytic activities, which might result in mature adipocyte dedifferentiation. In this study, we evaluated the influence of EGF and HC on the co-culture of endothelial cells and mature adipocytes regarding their cell morphology and functionality. We showed in mono-culture that high levels of HC promoted dedifferentiation and proliferation of mature adipocytes, whereas EGF seemed to have no negative influence. Endothelial cells kept their typical cobblestone morphology and showed a proliferation rate comparable to the control independent of EGF and HC concentration. In co-culture, HC promoted dedifferentiation of mature adipocytes, which was shown by a higher glycerol release. EGF had no negative impact on adipocyte morphology. No negative impact on endothelial cell morphology and functionality could be seen with reduced EGF and HC supplementation in co-culture with mature adipocytes. Taken together, our results demonstrate that reduced levels of HC are needed for co-culturing mature adipocytes and endothelial cells. In co-culture, EGF had no influence on mature adipocytes. Therefore, for the composition of vascularized adipose tissue constructs, the media with low levels of HC and high or low levels of EGF can be used. © 2016 International Federation for Cell Biology.

Isolated rat dental pulp cell culture and transplantation with an alginate scaffold.

Science.gov (United States)

Fujiwara, Shiro; Kumabe, Shunji; Iwai, Yasutomo

2006-05-01

Many studies have been conducted on tissue stem cells in the field of regenerative medicine, and cultured dental pulp mesenchymal cells have been reported to secrete dentin matrix. In the present study we used alginate as a scaffold to transplant subcultured rat dental-pulp-derived cells subcutaneously into the back of nude mice. We found that when beta-glycerophosphate was added to the culture medium, the mRNA of the dentin sialophosphoprotein (DSPP) gene coding dentin sialoprotein (DSP) and dentin phosphoprotein (DPP) was expressed, and an increase in alkaline phosphatase, an early marker of odontoblast differentiation, was also demonstrated. Six weeks after implantation, subcutaneous formation of radiopaque calcified bodies was observed in situ. Immunohistochemical and fine structure studies identified expression of type I collagen, type III collagen, and DSP in the mineralizing transplants, and isolated odontoblast-like cells began to form dentin-like hard tissue formation. Scattered autolyzing apoptotic cells were also observed in the transplants. The study showed that subcultured rat dental-pulp-derived cells actively differentiate into odontoblast-like cells and induce calcification in an alginate scaffold.

Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy.

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Costa, Marina; Cerqueira, Mariana T; Santos, Tírcia C; Sampaio-Marques, Belém; Ludovico, Paula; Marques, Alexandra P; Pirraco, Rogério P; Reis, Rui L

2017-06-01

Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditions for up to 8days in the absence of extrinsic growth factors. Immunocytochemistry against CD31 and CD146 revealed spontaneous organization in capillary-like structures, more complex after hypoxic conditioning. Inhibition of HIF-1α pathway hindered capillary-like structure formation in SVF cells cultured in hypoxia, suggesting a role of HIF-1α. Moreover, hypoxic SVF cells showed a trend for increased secretion of angiogenic factors, which was reflected in increased network formation by endothelial cells cultured on matrigel using that conditioned medium. In vivo implantation of SVF CS in a mouse hind limb ischemia model revealed that hypoxia-conditioned CS led to improved restoration of blood flow. Both in vitro and in vivo data suggest that SVF CS can be used as simple and cost-efficient tools to promote functional vascularization of TE constructs. Neovascularization after implantation is a major obstacle for producing clinically viable cell sheet-based tissue engineered constructs. Strategies using endothelial cells and extrinsic angiogenic growth factors are expensive and time consuming and may raise concerns of tumorigenicity. In this manuscript, we describe a simplified approach using angiogenic cell sheets fabricated from the stromal vascular fraction of adipose tissue. The strong angiogenic behavior of these cell sheets, achieved without the use of external growth factors, was further stimulated by low oxygen culture. When implanted in an in vivo model of hind limb

[Effects of feixin decoction on the contents of hypoxia-inducible factor-1alpha and vascular endothelial growth factor in the rat model of hypoxic pulmonary hypertension].

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He, Hong-Jun; Dai, Ai-Guo

2012-05-01

To explore the effects of Feixin Decoction (FXD) on the hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) in the rat model of hypoxic pulmonary hypertension (HPH), and to study its mechanisms for treating HPH. Forty healthy male SD rats were randomly divided into four groups, i. e., the normal control group, the HPH model group, the FXD group, and the Nifedipine group, 10 rats in each group. The HPH rat model was prepared using normal pressure intermittent hypoxia method. Except the normal control group, rats in the rest groups were fed in a self-made hypoxic plexiglass cabin, with the poor oxygen condition for 8 h daily for 14 successive days. Then the distilled water (at 30 mL/kg) was given by gastrogavage to rats in the normal control group and the HPH model group. FXD (at 28 g/kg) and Nifedipine (at 20 mg/kg) were given by gastrogavage to rats in the FXD group and the Nifedipine group respectively, once daily, for 14 successive days. Besides, hypoxia was continued for 14 days while medicating. The mean pulmonary artery pressure (mPAP) was detected on the second day after the last medication. The morphology of the pulmonary arteriole was detected. The ratio of pulmonary artery wall area and tube area (WA%) was determined. The protein and mRNA expressions of HIF-1alpha and VEGF were detected using immunohistochemistry and in situ hybridization technique. Compared with the normal control group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly increased in the model group (P < 0.01, P < 0.05). Compared with the HPH model group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly decreased in the FXD group (P < 0.01, P < 0.05). FXD down-regulated the expression of VEGF through decreasing the expression of HIF-1alpha. One of its mechanisms for treating HPH might be partially due to reversing the remodeling of pulmonary vascular smooth muscle.

Activation of vascular cholinergic and adrenergic receptors induced by gamma rays

International Nuclear Information System (INIS)

Alya, G.

1999-10-01

Activation of vascular cholinergic receptors and adrenoceptors plays an important role in vasomotoricity and peripheric vascular resistance. These factors are essential in maintaining a stable blood pressure. The aim of this study is to investigate the radiosensitivity differences between vascular cholinergic receptors and adrenoceptors, and consequently to determinate the effects of ionizing radiation (whole body irradiation) on contractile response regulation of vascular smooth muscle fibers VSMF isolated from rat portal vein. Our results show that Clonidine, (non-specific adrenergic agonist), and phenylephrine which is more specific α1-adrenoceptor agonist, increase the VSMF contractions. The maximum effect is obtained at 10 -5 - 3.10 -5 M. On irradiated rats (1-3-5 Gy), there is an important shift thus, the maximal response (E m ax) can be obtained in lower concentrations of clonidine and phenylephrine. Irradiation deceases the contractile responses of VSMF mediated by cholinergic stimulation, in a dose dependant manner. With E m ax 1 Gy>E m ax 3 Gy>E m ax 5 Gy. Irradiated muscular fibers became less sensitive to acetylcholine, thus 3.10 -8 M. A. ch induced more than 50% of contraction force increase in normal conditions. This concentration induce generally a negligible effect after irradiation. The results reveal the existence of radiosensitivity differences between vascular cholinergic and adrenergic receptors. (author)

Bone Morphogenetic Proteins 2/4 Are Upregulated during the Early Development of Vascular Calcification in Chronic Kidney Disease

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Xiao Wei

2018-01-01

Full Text Available Vascular calcification is a main cause of increased cardiovascular morbidity and mortality in chronic kidney disease (CKD patients. This study aimed to investigate the role of the bone morphogenetic protein (BMP signaling pathway in the early development of vascular calcification in CKD. A CKD vascular calcification rat model was established by providing rats with a 1.8% high-phosphorus diet and an intragastric administration of 2.5% adenine suspension. The kidney and aortic pathologies were analyzed. Blood biochemical indicators, serum BMP-2 and BMP-4 levels, and aortic calcium content were determined. The expression levels of BMP-2, BMP-4, bone morphogenetic protein receptor-IA (BMPR-IA, and matrix Gla protein (MGP in aorta were examined by quantitative real-time polymerase chain reaction and immunohistochemistry. Compared with the normal control (Nor rats, the CKD rats exhibited a significantly decreased body weight and an increased kidney weight as well as abnormal renal function and calcium-phosphorus metabolism. Aortic von Kossa and Alizarin red staining showed massive granular deposition and formation of calcified nodules in aorta at 8 weeks. The aortic calcium content was significantly increased, which was positively correlated with the serum BMP-2 (r=0.929; P<0.01 and serum BMP-4 (r=0.702; P<0.01 levels in CKD rats. The rat aortic BMP-2 mRNA level in the CKD rats was persistently increased, and the BMP-4 mRNA level was prominently increased at the 4th week, declining thereafter. Strong staining of BMP-2, BMP-4, BMPR-IA, and MGP proteins was observed in the tunica media of the aorta from the 4th week after model induction. In conclusion, activation of the BMP signaling pathway is involved in the early development of vascular calcification in CKD. Therefore, elevated serum BMP-2 and BMP-4 levels may serve as serum markers for CKD vascular calcification.

Gel entrapment culture of rat hepatocytes for investigation of tetracycline-induced toxicity

International Nuclear Information System (INIS)

Shen Chong; Meng Qin; Schmelzer, Eva; Bader, Augustinus

2009-01-01

This paper aimed to explore three-dimensionally cultured hepatocytes for testing drug-induced nonalcoholic steatohepatitis. Gel entrapped rat hepatocytes were applied for investigation of the tetracycline-induced steatohepatitis, while hepatocyte monolayer was set as a control. The toxic responses of hepatocytes were systematically evaluated by measuring cell viability, liver-specific function, lipid accumulation, oxidative stress, adenosine triphosphate content and mitochondrial membrane potential. The results suggested that gel entrapped hepatocytes showed cell death after 96 h of tetracycline treatment at 25 μM which is equivalent to toxic serum concentration in rats, while hepatocyte monolayer showed cell death at a high dose of 200 μM. The concentration-dependent accumulation of lipid as well as mitochondrial damage were regarded as two early events for tetracycline hepatotoxicity in gel entrapment culture due to their detectability ahead of subsequent increase of oxidative stress and a final cell death. Furthermore, the potent protection of fenofibrate and fructose-1,6-diphosphate were evidenced in only gel entrapment culture with higher expressions on the genes related to β-oxidation than hepatocyte monolayer, suggesting the mediation of lipid metabolism and mitochondrial damage in tetracycline toxicity. Overall, gel entrapped hepatocytes in three-dimension reflected more of the tetracycline toxicity in vivo than hepatocyte monolayer and thus was suggested as a more relevant system for evaluating steatogenic drugs.

The mechanism of inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells

International Nuclear Information System (INIS)

Zhuang Yongzhi; Wang Junjie; Zhang Zhanchun; Jia Tingzhen

2001-01-01

Objective: To investigate the inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells (VSMCs). Methods: Dose-survival curve of VSMCs was figured by colony formation. The effect of γ-ray irradiation on viability and proliferation of VSMCs was observed by 3 H incorporation. Flow cytometry and DNA Ladder were used to detect the apoptosis effect of γ-ray irradiation on VSMCs. Results: The values of D 0 , D q , D 37 and N for VSMCs were 1.95 Gy, 1.76 Gy, 3.71 Gy and 2.47, respectively. The inhibitory effect of γ-ray irradiation on VSMCs proliferation was dose-dependent, being stronger along with increase of dose. VSMCs did not undergo apoptosis within 48 hours after γ-ray irradiation. Conclusion: γ-ray irradiation could inhibit the proliferation of VSMCs, the main mechanism of which is the killing effect and inhibition of mitosis of VSMCs

Aqueous extract of Allium sativum L bulbs offer nephroprotection by attenuating vascular endothelial growth factor and extracellular signal-regulated kinase-1 expression in diabetic rats.

Science.gov (United States)

Shiju, T M; Rajkumar, R; Rajesh, N G; Viswanathan, Pragasam

2013-02-01

To investigate the nephroprotective effect of garlic and elucidate the mechanism by which it prevents the progression of diabetic nephropathy in diabetic rats, diabetes was induced by a single ip injection of streptozotocin (45 mg/kg body weight). Garlic extract (500 mg/kg body weight) and aminoguanidine (1 g/L) were supplemented in the treatment groups. Histopathological examination using H&E, PAS staining and the immunohistochemical analysis of vascular endothelial growth factor (VEGF) and extracellular signal-regulated kinase-1 (ERK-1) expression were performed on kidney sections at the end of 12 weeks. Significant change in both, the urine and serum biochemistry confirmed kidney damage in diabetic animals which was further confirmed by the histological changes such as mesangial expansion, glomerular basement membrane thickening, glycosuria and proteinuria. However, the diabetic animals treated with garlic extract showed a significant change in urine and serum biochemical parameters such as albumin, urea nitrogen and creatinine compared to that of diabetic rats. Further, the garlic supplemented diabetic rats showed a significant decrease in the expression of VEGF and ERK-1 compared to diabetic rats, attenuating mesangial expansion and glomerulosclerosis. Thus, garlic extract rendered nephroprotection in diabetic rats.

Vascular endothelial growth factor (VEGF), produced by feline infectious peritonitis (FIP) virus-infected monocytes and macrophages, induces vascular permeability and effusion in cats with FIP.

Science.gov (United States)

Takano, Tomomi; Ohyama, Taku; Kokumoto, Aiko; Satoh, Ryoichi; Hohdatsu, Tsutomu

2011-06-01

Feline infectious peritonitis virus (FIPV) causes a fatal disease called FIP in Felidae. The effusion in body cavity is commonly associated with FIP. However, the exact mechanism of accumulation of effusion remains unclear. We investigated vascular endothelial growth factor (VEGF) to examine the relationship between VEGF levels and the amounts of effusion in cats with FIP. Furthermore, we examined VEGF production in FIPV-infected monocytes/macrophages, and we used feline vascular endothelial cells to examine vascular permeability induced by the culture supernatant of FIPV-infected macrophages. In cats with FIP, the production of effusion was related with increasing plasma VEGF levels. In FIPV-infected monocytes/macrophages, the production of VEGF was associated with proliferation of virus. Furthermore, the culture supernatant of FIPV-infected macrophages induced hyperpermeability of feline vascular endothelial cells. It was suggested that vascular permeability factors, including VEGF, produced by FIPV-infected monocytes/macrophages might increase the vascular permeability and the amounts of effusion in cats with FIP. Copyright © 2011 Elsevier B.V. All rights reserved.

In vitro model of vascularized bone: synergizing vascular development and osteogenesis.

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Cristina Correia

Full Text Available Tissue engineering provides unique opportunities for regenerating diseased or damaged tissues using cells obtained from tissue biopsies. Tissue engineered grafts can also be used as high fidelity models to probe cellular and molecular interactions underlying developmental processes. In this study, we co-cultured human umbilical vein endothelial cells (HUVECs and human mesenchymal stem cells (MSCs under various environmental conditions to elicit synergistic interactions leading to the colocalized development of capillary-like and bone-like tissues. Cells were encapsulated at the 1:1 ratio in fibrin gel to screen compositions of endothelial growth medium (EGM and osteogenic medium (OM. It was determined that, to form both tissues, co-cultures should first be supplied with EGM followed by a 1:1 cocktail of the two media types containing bone morphogenetic protein-2. Subsequent studies of HUVECs and MSCs cultured in decellularized, trabecular bone scaffolds for 6 weeks assessed the effects on tissue construct of both temporal variations in growth-factor availability and addition of fresh cells. The resulting grafts were implanted subcutaneously into nude mice to determine the phenotype stability and functionality of engineered vessels. Two important findings resulted from these studies: (i vascular development needs to be induced prior to osteogenesis, and (ii the addition of additional hMSCs at the osteogenic induction stage improves both tissue outcomes, as shown by increased bone volume fraction, osteoid deposition, close proximity of bone proteins to vascular networks, and anastomosis of vascular networks with the host vasculature. Interestingly, these observations compare well with what has been described for native development. We propose that our cultivation system can mimic various aspects of endothelial cell-osteogenic precursor interactions in vivo, and could find utility as a model for studies of heterotypic cellular interactions that

Luteolin Ameliorates Hypertensive Vascular Remodeling through Inhibiting the Proliferation and Migration of Vascular Smooth Muscle Cells

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Jie Su

2015-01-01

Full Text Available Objectives. Preliminary researches showed that luteolin was used to treat hypertension. However, it is still unclear whether luteolin has effect on the hypertensive complication such as vascular remodeling. The present study was designed to investigate the effect of luteolin on the hypertensive vascular remodeling and its molecular mechanism. Method and Results. We evaluated the effect of luteolin on aorta thickening of hypertension in spontaneous hypertensive rats (SHRs and found that luteolin could significantly decrease the blood pressure and media thickness of aorta in vivo. Luteolin could inhibit angiotensin II- (Ang II- induced proliferation and migration of vascular smooth muscle cells (VSMCs. Dichlorofluorescein diacetate (DCFH-DA staining result showed that luteolin reduced Ang II-stimulated ROS production in VSMCs. Furthermore, western blot and gelatin zymography results showed that luteolin treatment leaded to a decrease in ERK1/2, p-ERK1/2, p-p38, MMP2, and proliferating cell nuclear antigen (PCNA protein level. Conclusion. These data support that luteolin can ameliorate hypertensive vascular remodeling by inhibiting the proliferation and migration of Ang II-induced VSMCs. Its mechanism is mediated by the regulation of MAPK signaling pathway and the production of ROS.

Regulation of pro-adrenocorticotropin-endorphin synthesis and secretion in cultured neonatal rat anterior pituitary

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Sato, S.M.; Mains, R.E. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

1987-08-01

Previous work demonstrated that newborn rat anterior pituitary corticotropes display processing patterns for pro-ACTH/endorphin that are different from the adult. The synthesis and release of beta-endorphin-related peptides was examined in dispersed cell and explant cultures of newborn anterior pituitary to investigate corticotrope development further. The temporal pattern of pro-ACTH/endorphin processing differed significantly from adult rat melanotropes and AtT-20 cells. While pro-ACTH/endorphin processing begins within 30 min of synthesis in adult melanotropes and AtT-20 cells, pulse-labeling of newborn corticotropes in culture indicated that pro-ACTH/endorphin remained uncleaved for at least 90 min after synthesis. With further incubation, there was a decrease in radioactivity associated with the precursor and an equivalent rise in the radioactivity associated with beta-endorphin and beta-lipotropin. However, unprocessed precursor still remained in the cultured newborn anterior pituitary cells after a 25-h chase. Although intact pro-ACTH/endorphin from newborn corticotropes was very long-lived, the precursor did undergo oligosaccharide maturation and became endoglycosidase H resistant within 1 h after synthesis. Similar to the adult, pro-ACTH/endorphin synthesis was doubled in cultures of newborn anterior pituitary chronically treated with 10 nM CRF resulting in a 3- to 4-fold stimulation of secretion over the basal rate. However, unlike the AtT-20 cell or adult rat corticotrope, the proteolytic processing of pro-ACTH/endorphin in the newborn corticotrope was altered by chronic secretagogue treatment; less pro-ACTH/endorphin was converted to beta-endorphin in secretagogue-treated corticotropes than in controls. Thus processing of pro-ACTH/endorphin in the corticotrope is not mature by birth and can be regulated by chronic CRF treatment.

Regulation of pro-adrenocorticotropin-endorphin synthesis and secretion in cultured neonatal rat anterior pituitary

International Nuclear Information System (INIS)

Sato, S.M.; Mains, R.E.

1987-01-01

Previous work demonstrated that newborn rat anterior pituitary corticotropes display processing patterns for pro-ACTH/endorphin that are different from the adult. The synthesis and release of beta-endorphin-related peptides was examined in dispersed cell and explant cultures of newborn anterior pituitary to investigate corticotrope development further. The temporal pattern of pro-ACTH/endorphin processing differed significantly from adult rat melanotropes and AtT-20 cells. While pro-ACTH/endorphin processing begins within 30 min of synthesis in adult melanotropes and AtT-20 cells, pulse-labeling of newborn corticotropes in culture indicated that pro-ACTH/endorphin remained uncleaved for at least 90 min after synthesis. With further incubation, there was a decrease in radioactivity associated with the precursor and an equivalent rise in the radioactivity associated with beta-endorphin and beta-lipotropin. However, unprocessed precursor still remained in the cultured newborn anterior pituitary cells after a 25-h chase. Although intact pro-ACTH/endorphin from newborn corticotropes was very long-lived, the precursor did undergo oligosaccharide maturation and became endoglycosidase H resistant within 1 h after synthesis. Similar to the adult, pro-ACTH/endorphin synthesis was doubled in cultures of newborn anterior pituitary chronically treated with 10 nM CRF resulting in a 3- to 4-fold stimulation of secretion over the basal rate. However, unlike the AtT-20 cell or adult rat corticotrope, the proteolytic processing of pro-ACTH/endorphin in the newborn corticotrope was altered by chronic secretagogue treatment; less pro-ACTH/endorphin was converted to beta-endorphin in secretagogue-treated corticotropes than in controls. Thus processing of pro-ACTH/endorphin in the corticotrope is not mature by birth and can be regulated by chronic CRF treatment

Glyoxalase-1 overexpression reduces endothelial dysfunction and attenuates early renal impairment in a rat model of diabetes

DEFF Research Database (Denmark)

Brouwers, Olaf; Niessen, Petra M G; Miyata, Toshio

2014-01-01

AIMS/HYPOTHESIS: In diabetes, advanced glycation end-products (AGEs) and the AGE precursor methylglyoxal (MGO) are associated with endothelial dysfunction and the development of microvascular complications. In this study we used a rat model of diabetes, in which rats transgenically overexpressed...... the MGO-detoxifying enzyme glyoxalase-I (GLO-I), to determine the impact of intracellular glycation on vascular function and the development of early renal changes in diabetes. METHODS: Wild-type and Glo1-overexpressing rats were rendered diabetic for a period of 24 weeks by intravenous injection...... podocyte number and diabetes-induced elevation of urinary markers albumin, osteopontin, kidney-inflammation-molecule-1 and nephrin) were attenuated by Glo1 overexpression. In line with this, downregulation of Glo1 in cultured endothelial cells resulted in increased expression of inflammation...

ATP and UTP responses of cultured rat aortic smooth muscle cells revisited: dominance of P2Y2 receptors

Science.gov (United States)

Kumari, Rajendra; Goh, Gareth; Ng, Leong L; Boarder, Michael R

2003-01-01

It has previously been shown that ATP and UTP stimulate P2Y receptors in vascular smooth muscle cells (VSMCs), but the nature of these receptors, in particular the contribution of P2Y2 and P2Y4 subtypes, has not been firmly established. Here we undertake a further pharmacological analysis of [3H]inositol polyphosphate responses to nucleotides in cultured rat VSMCs. ATP generated a response that was partial compared to UTP, as reported earlier. In the presence of a creatine phosphokinase (CPK) system for regenerating nucleoside triphosphates, the response to ATP was increased, the response to UTP was unchanged, and the difference between UTP and ATP concentration–response curves disappeared. Chromatographic analysis showed that ATP was degraded slightly faster than UTP. The response to UDP was always smaller than that to UTP, but with a shallow slope and a high potency component. In the presence of hexokinase (which prevents the accumulation of ATP/UTP from ADP/UDP), the maximum response to UDP was reduced and the high-potency component of the curve was retained. By contrast, the response to ADP was weaker throughout in the presence of hexokinase. ATPγS was an effective agonist with a similar EC50 to UTP, but with a lower maximum. ITP was a weak agonist compared with UTP. Suramin was an effective antagonist of the response to UTP (pA2=4.48), but not when ATP was the agonist. However, suramin was an effective antagonist (pA2=4.45) when stimulation with ATP was in the presence of the CPK regenerating system. Taken together with the results of others, these findings indicate that the response of cultured rat VSMCs to UTP and to ATP is predominantly at the P2Y2 receptor, and that there is also a response to UDP at the P2Y6 receptor. PMID:14597595

Electroacupuncture decreases the progression of ovarian hyperstimulation syndrome in a rat model.

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Chen, Li; Sun, Hai-Xiang; Xia, You-Bing; Sui, Liu-Cai; Zhou, Ji; Huang, Xuan; Zhou, Jing-Wei; Shao, Yi-Dan; Shen, Tao; Sun, Qin; Liang, Yuan-Jiao; Yao, Bing

2016-05-01

This study aimed to elucidate the effect of electroacupuncture treatment on preventing early ovarian hyperstimulation syndrome (OHSS) and the potential mechanisms involved using an induced rat model. The ovarian response was examined by measuring ovary weight, vascular permeability, levels of inflammation (interleukin-6), tumour necrosis factor alpha, chemokine ligand 2 (also known as monocyte chemoactic protein 1), vascular endothelial growth factor and hormone concentrations (oestradiol, progesterone, testosterone and prolactin). Sprague-Dawley female rats underwent ovarian stimulation to induce OHSS. Hyperstimulated rats received consecutive electroacupuncture treatment from 3 days before the beginning of pregnant mare serum gonadotrophin treatment or the time point of pregnant mare serum gonadotrophin treatment respectively, and last until 3 days after HCG administration. Electroacupuncture treatment reduced ovary weight and vascular permeability in hyperstimulated rats. Electroacupuncture treatment also reduced the levels of serum steroid hormones (progesterone and testosterone), inflammatory cytokines (interleukin-6, tumour necrosis factor alpha and monocyte chemotactic protein 1 and vascular endothelial growth factor in hyperstimulated rats. The results indicate that electroacupuncture can modulate endocrine hormone secretion and affect the secretion of inflammatory cytokines and vascular endothelial growth factor, and thus prevent the progress of OHSS. Electroacupuncture may provide a simple and effective method for the prevention and treatment of OHSS. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

VIP and its homologous increase vascular conductance in certain endocrine and exocrine glands

International Nuclear Information System (INIS)

Huffman, L.J.; Connors, J.M.; Hedge, G.A.

1988-01-01

The effects of vasoactive intestinal peptide (VIP) and related structural homologues on tissue vascular conductances were investigated in anesthetized male rats. VIP, peptide histidine isoleucine (PHI), secretin, growth hormone-releasing factor (GHRF), gastric inhibitory peptide (GIP), or saline was infused intravenously over 4 min. Tissue blood flows were measured during this time by use of 141 Ce-labeled microspheres. Circulating thyrotropin (TSH), triiodothyronine (T 3 ), and thyroxine (T 4 ) levels were determined before and at 20 min and 2 h after treatment. Marked increases in thyroid, pancreatic, and salivary gland vascular Cs occurred during peptide infusion with the order of potency correlating with the degree of structural homology to VIP. PHI and secretin produced maximal increases in vascular Cs, which were the same as those obtained with VIP. Circulating TSH, T 3 , and T 4 levels were not different from values in saline-infused rats after peptide treatments that caused striking increases in thyroid vascular C. These observations indicate that the vascular beds of certain endocrine and exocrine glands are responsive to the vasodilatory action of VIP and related homologues with the order of potency corresponding to the degree of structural homology to VIP. These results are also consistent with the proposal that structural homologues of VIP act at the same vascular receptor as VIP. Alternative, the involvement of different vascular receptors, acting through the same mechanism at a level beyond the receptor site, cannot be excluded

The behavior of the vascular system in the experimental tumor radiotherapy

International Nuclear Information System (INIS)

Yamaura, Hirotsugu; Matsuzawa, Taiju; Sato, Haruo; Ito, Yasuhiko.

1975-01-01

The rat ascites hepatoma AH109A transplanted and grown in the rat transparent chamber developed a tumor specific vascular system, the process of which was quantitatively studied because of the vascular length, surface area, and volume per mm 3 of tissue. The values changed characteristically in each stage of the course. The tumor was irradiated in a chamber with 3000 R of 60 Co γ-rays, and the tumor cells died leaving behind highly dense capillary networks, which gradually returned to normal level by 7 days after irradiation. The blood vessels, either preformed or newly formed, in the control tissue without tumor were not damaged by this dose. But the proliferation of capillary buds were inhibited slightly with 400 R and completely with 4000 R. (auth.)

The effect of Scutellaria baicalensis stem-leaf flavonoids on spatial learning and memory in chronic cerebral ischemia-induced vascular dementia of rats.

Science.gov (United States)

Cao, Yanjing; Liang, Lizhen; Xu, Jian; Wu, Jiali; Yan, Yongxing; Lin, Ping; Chen, Qiang; Zheng, Fengming; Wang, Qin; Ren, Qian; Gou, Zengmei; Du, Yifeng

2016-05-01

Flavonoids have been shown to improve cognitive function and delay the dementia progression. However, the underlying mechanisms remain elusive. In the present study, we examined the effect of Scutellaria baicalensis stem-leaf total flavonoids (SSTFs) extracted from S. baicalensis Georgi on spatial learning and memory in a vascular dementia (VaD) rat model and explored its molecular mechanisms. The VaD rats were developed by permanent bilateral occlusion of the common carotid artery. Seven days after recovery, the VaD rats were treated with either 50 or 100 mg/kg of SSTF for 60 days. The spatial learning and memory was evaluated in the Morris water maze (MWM) test. The tau hyperphosphorylation and the levels of the related protein kinases or phosphatases were examined by western blot analysis. In VaD rats, SSTF treatment at 100 mg/kg significantly reduced the escape latency in training trial in MWM test. In the probe trial, SSTF treatment increased the searching time and travel distance in the target quadrant. SSTF treatment inhibited the tau phosphorylation in both cortex and hippocampus in VaD rats. Meanwhile, SSTF reduced the activity of glycogen synthase kinase 3β and cyclin-dependent kinase 5 in VaD rats. In contrast, SSTF treatment increased the level of the protein phosphatase 2A subunit B in VaD rats. SSTF treatment significantly improved the spatial cognition in VaD rats. Our results suggest that SSTF may alleviate tau-hyperphosphorylation-induced neurotoxicity through coordinating the activity of kinases and phosphatase after a stroke. SSTF may be developed into promising novel therapeutics for VaD. © The Author 2016. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

Activation of protein kinase C by elevation of glucose concentration: Proposal for a mechanism in the development of diabetic vascular complications

International Nuclear Information System (INIS)

Lee, Tianshing; Saltsman, K.A.; Ohashi, Hiromi; King, G.L.

1989-01-01

Hyperglycemia is believed to be the major cause of diabetic vascular complications involving both microvessels and arteries as in the retina, renal glomeruli, and aorta. It is unclear by which mechanism hyperglycemia is altering the metabolism and functions of vascular cells, although changes in nonenzymatic protein glycosylation and increases in cellular sorbitol levels have been postulated to be involved. Previously, the authors have reported that the elevation of extracellular glucose levels with cultured bovine retinal capillary endothelial cells causes an increase in protein kinase C (PKC) activity of the membranous pool with a parallel decrease in the cytosol without alteration of its total activity. Now they demonstrate that the mechanism for the activation of PKC is due to an enhanced de novo synthesis of diacylglycerol as indicated by a 2-fold increase of [ 14 C]diacylglycerol labeling from [ 14 C]glucose. The elevated diacylglycerol de novo synthesis is secondarily due to increased formation of precursors derived from glucose metabolism; this formation is enhanced by hyperglycemia as substantiated by elevated [ 3 H]glucose conversion into water. This effect of hyperglycemia on PKC is also observed in cultured aortic smooth muscle and endothelial cells and the retina and kidney of diabetic rats, but not in the brain. Since PKC in vascular cells has been shown to modulate hormone receptor turnover, neovascularization in vitro, and cell growth, they propose that this mechanism of enhancing the membranous PKC activities by hyperglycemia plays an important role in the development of diabetic vascular complications

Extracellular matrix components influence DNA synthesis of rat hepatocytes in primary culture

International Nuclear Information System (INIS)

Sawada, N.; Tomomura, A.; Sattler, C.A.; Sattler, G.L.; Kleinman, H.K.; Pitot, H.C.

1986-01-01

The effects of several extracellular matrix components (EMCs) - fibronectin (Fn), laminin (Ln), type I (C-I) and type IV (C-IV) collagen - on DNA synthesis in rat hepatocytes in primary culture were examined by both quantitative scintillation spectrometry and autoradiography of [ 3 H]thymidine incorporation. Hepatocytes cultured on Fn showed the most active DNA synthesis initiated by epidermal growth factor (EGF) with decreasing levels of [ 3 H]thymidine uptake exhibited in the cell cultured on C-IV, C-I, and Ln, respectively. The decreasing level of DNA synthesis in hepatocytes cultured on Fn, C-IV, C-I, and Ln respectively was not influenced by cell density. The number of EGF receptors of hepatocytes was also not influenced by EMCs. These data suggest that EMCs modify hepatocyte DNA synthesis by means of post-EGF-receptor mechanisms which are regulated by both growth factors and cell density

Distinct angiotensin II receptor in primary cultures of glial cells from rat brain

International Nuclear Information System (INIS)

Raizada, M.K.; Phillips, M.I.; Crews, F.T.; Sumners, C.

1987-01-01

Angiotensin II (Ang-II) has profound effects on the brain. Receptors for Ang-II have been demonstrated on neurons, but no relationship between glial cells and Agn-II has been established. Glial cells (from the hypothalamus and brain stem of 1-day-old rat brains) in primary culture have been used to demonstrate the presence of specific Ang-II receptors. Binding of 125 I-Ang-II to glial cultures was rapid, reversible, saturable, and specific for Ang-II. The rank order of potency of 125 I-Ang-II binding was determined. Scatchard analysis revealed a homogeneous population of high-affinity binding sites with a B/sub max/ of 110 fmol/mg of protein. Light-microscopic autoradiography of 125 I-Ang-II binding supported the kinetic data, documenting specific Ang-II receptors on the glial cells. Ang-II stimulated a dose-dependent hydrolysis of phosphatidylinositols in glial cells, an effect mediated by Ang-II receptors. However, Ang-II failed to influence [ 3 H] norepinephrine uptake, and catecholamines failed to regulate Ang-II receptors, effects that occur in neurons. These observations demonstrate the presence of specific Ang-II receptors on the glial cells in primary cultures derived from normotensive rat brain. The receptors are kinetically similar to, but functionally distinct from, the neuronal Ang-II receptors

[Intramuscular injection of lentivirus-mediated EPAS1 gene improves hind limb ischemia and its mechanism in a rat model of peripheral artery vascular disease].

Science.gov (United States)

Wang, Zhihong; Gu, Hongbin; Yang, Fan; Xie, Huajie; Sheng, Lei; Li, Mingfei

2017-11-01

Objective To investigate the effect of over-expressed endothelial Per-Arnt-Sim domain protein 1 (EPAS1) on peripheral arterial disease (PAD) in a rat model. Methods PAD rat model was established by external iliac artery ligation followed by lentivirus-mediated EPAS1 gene injection into rat right adductor magnus. The models were evaluated by quantitative analysis of gait disturbance. The changes of blood flow in the posterior extremity of the rats were detected using laser Doppler. The expressions of EPAS1, hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) mRNAs were tested by real-time quantitative PCR. The expression of α-smooth muscle actin (αSMA) was detected by immunohistochemical staining. Results Compared with lenti-EGFP group, rat hind limb function and circulation got recovered obviously 7 days after lenti-EPAS1 injection. The mRNA expressions of EPAS1, HGF, bFGF, and VEGF were up-regulated in the lenti-EPAS1-treated sites.The expression of αSMA showed an obvious increase in the lenti-EPAS1-treated muscles. Conclusion Over-expressed lenti-EPAS1 can promote angiogenesis via the up-regulation of EPAS1-related angiogenic factors in the muscles of the affected hind limb and reduce gait disturbance.

Effects of spontaneously hypertensive rat plasma on blood pressure and tail artery calcium uptake in normotensive rats

International Nuclear Information System (INIS)

Lewanczuk, R.Z.; Wang, J.; Zhang, Z.R.; Pang, P.K.

1989-01-01

Previous studies have described the presence of humoral hypertensive factors in spontaneously hypertensive rats (SHR). Other studies have described factors that increase calcium uptake in vascular tissue. In this study, we attempted to confirm, and thereby correlate, the presence of both types of factors in SHR plasma. Intravenous infusion or bolus administration of dialyzed SHR plasma consistently induced an increase in blood pressure in normotensive rats. This hypertensive response was somewhat delayed, with peak blood pressures occurring 45 minutes after bolus administration and 90 minutes after infusion of SHR plasma. Spontaneously hypertensive rat plasma also increased 45 Ca uptake in isolated normotensive rat tail arteries in a dose-dependent manner, with a time course similar to that for the hypertensive response to bolus administration. These findings suggest, therefore, that a substance exists in SHR plasma that can increase intracellular calcium in vascular tissues and thereby increase blood pressure

Comparison of radiometric and conventional culture systems in detecting Haemophilus influenzae type b bacteremia in rats

International Nuclear Information System (INIS)

Mitchell, M.J.; Zwahlen, A.; Elliott, H.L.; Ford, N.K.; Charache, F.P.; Moxon, E.R.

1985-01-01

To compare the efficiency of detecting Haemophilus influenzae type b bacteremia by the BACTEC radiometric system and a conventional Trypticase soy broth blood culture system, the authors developed an in vivo model of bacteremia in rats. After intravenous injection of 50 to 200 CFU into adult rats, there was a linear logarithmic increase in CFU per milliliter of rat blood during the first 10 h (r = 0.98), allowing accurate prediction of the level of bacteremia with time. Culture bottles were inoculated with 0.5 ml of blood obtained by cardiac puncture and processed as clinical samples in the microbiology laboratory with RS and conventional protocols. They found the following. (i) The first detection of bacteremia by RS was similar to that by TSB if a Gram stain of the TSB was done on day 1 and was superior if that smear was omitted (P less than 0.01). (ii) The detection times in both systems were comparable at different magnitudes of bacteremia (10(1) to 10(4) CFU/ml). (iii) Supplementation of inoculated bottles with 2 ml of sterile rat blood interfered with Gram stain detection in TSB but resulted in increased 14 CO 2 production in RS. (iv) No difference in detection time was found between RS and TSB for four different clinical isolates. These studies show that, in a biologically relevant model, the detection of positive blood cultures for H. influenzae type b by RS was comparable to or better than detection by TSB when blood was processed analogously to clinical specimens

Transplantation of mesenchymal stem cells cultured on biomatrix support induces repairing of digestive tract defects, in animal model.

Science.gov (United States)

Sîrbu-Boeţi, Mirela-Patricia; Chivu, Mihaela; Pâslaru, Liliana Livia; Efrimescu, C; Herlea, V; Pecheanu, C; Moldovan, Lucia; Dragomir, Laura; Bleotu, Coralia; Ciucur, Elena; Vidulescu, Cristina; Vasilescu, Mihaela; Boicea, Anişoara; Mănoiu, S; Ionescu, M I; Popescu, I

2009-01-01

Transplanted mesenchymal stem cells (MSCs) appear to play a significant role in adult tissue repair. The aim of this research was to obtain MSCs enriched, three dimensional (3D) patches for transplant, and to test their ability to induce repair of iatrogenic digestive tract defects in rats. MSCs were obtained from human and rat bone marrow, cultured in vitro, and seeded in a collagen-agarose scaffold, where they showed enhanced viability and proliferation. The phenotype of the cultured cells was representative for MSCs (CD105+, CD90+, and CD34-, CD45-, CD3-, CD14-). The 3D patch was obtained by laying the MSCs enriched collagen-agarose scaffold on a human or swine aortic fragment. After excision of small portions of the rat digestive tract, the 3D patches were sutured at the edge of the defect using micro-surgical techniques. The rats were sacrificed at time-points and the regeneration of the digestive wall was investigated by immunofluorescence, light and electron microscopy. The MSCs enriched 3D patches were biocompatible, biodegradable, and prompted the regeneration of the four layers of the stomach and intestine wall in rats. Human cells were identified in the rat regenerated digestive wall as a hallmark of the transplanted MSCs. For the first time we constructed 3D patches made of cultured bone marrow MSCs, embedded into a collagen-rich biomatrix, on vascular bio-material support, and transplanted them in order to repair iatrogenic digestive tract defects. The result was a complete repair with preservation of the four layered structure of the digestive wall.

The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells

International Nuclear Information System (INIS)

Perez-Vizcaino, Francisco; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A.; Warner, Timothy D.

2006-01-01

Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPARγ, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin

Acute effects of gamma irradiation on vascular arterial tone

International Nuclear Information System (INIS)

Bourlier, V.; Diserbo, M.; Multon, E.; Verdetti, J.; Fatome, M.

1995-01-01

In rat aortic rings, we showed an increase in arterial tone during irradiation. This effect is acute reversible. This effect is only observed on pre-contracted rings and needs the integrity of vascular endothelium. The molecular mechanism of this effect is discussed. (author)

Effects of Chinese yellow wine on nitric oxide synthase and intercellular adhesion molecule-1 expressions in rat vascular endothelial cells.

Science.gov (United States)

Zhao, Fei; Ji, Zheng; Chi, Jufang; Tang, Weiliang; Zhai, Xiaoya; Meng, Liping; Guo, Hangyuan

2016-02-01

The objective of this study was to determine similarities in the effect of yellow wine as compared to statin and the possibility that yellow wine inhibits tumour necrosis factor-α (TNF-α)-induced nitric oxide (NO) synthesis, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and intercellular adhesion molecule-1 (ICAM-1) in cultured rat vascular endothelial cells (VECs). We isolated VECs, and cultivated and purified Sprague Dawley (SD) rat thoracic aortas in vitro. We selected the optimal wine concentration using clonogenic and MTT assays to measure cell survival. Next, we divided the cells into 9 groups: (1) control, (2) TNF-α, (3) TNF-α + rosuvastatin (10 μmol/L), (4) TNF-α + ethanol 0.5%, (5) TNF-α + yellow wine 0.5%, (6) TNF-α + ethanol 1.0%, (7) TNF-α + yellow wine 1.0%, (8) TNF-α + ethanol 1.5%, and (9) TNF-α + yellow wine 1.5% and they were given the corresponding treatment for 24 h. We determined NO production with nitrate reductase. We then measured eNOS activity, and detected eNOS, iNOS, and ICAM-1 protein levels by Western blotting. Compared with the TNF-α group, NO production, eNOS activity, and eNOS protein expression in the rosuvastatin, and yellow wine 1.0%, and 1.5% groups were significantly increased. Protein expression of iNOS and ICAM-1 in the rosuvastatin, yellow wine 1.0%, and 1.5% groups were significantly decreased. Compared with the rosuvastatin group, eNOS, iNOS, and ICAM-1 protein expression in the yellow wine (0.5% -1.5%) groups were significantly different. Treatment with yellow wine increased NO production, eNOS activity, and eNOS protein expression, which decreases iNOS and ICAM-1 protein expression. We conclude that yellow wine may have similar beneficial effects as rosuvastatin on the cardiovascular system. These effects may be attributed to their anti-atherosclerotic actions.

The in vivo blood compatibility of bio-inspired small diameter vascular graft: effect of submicron longitudinally aligned topography

Science.gov (United States)

2013-01-01

Background Cardiovascular disease is the leading cause of deaths worldwide and the arterial reconstructive surgery remains the treatment of choice. Although large diameter vascular grafts have been widely used in clinical practices, there is an urgent need to develop a small diameter vascular graft with enhanced blood compatibility. Herein, we fabricated a small diameter vascular graft with submicron longitudinally aligned topography, which mimicked the tunica intima of the native arterial vessels and were tested in Sprague–Dawley (SD) rats. Methods Vascular grafts with aligned and smooth topography were prepared by electrospinning and were connected to the abdominal aorta of the SD rats to evaluate their blood compatibility. Graft patency and platelet adhesion were evaluated by color Doppler ultrasound and immunofluorescence respectively. Results We observed a significant higher patency rate (p = 0.021) and less thrombus formation in vascular graft with aligned topography than vascular graft with smooth topography. However, no significant difference between the adhesion rates on both vascular grafts (smooth/aligned: 0.35‰/0.12‰, p > 0.05) was observed. Moreover, both vascular grafts had few adherent activated platelets on the luminal surface. Conclusion Bionic vascular graft showed enhanced blood compatibility due to the effect of surface topography. Therefore, it has considerable potential for using in clinical application. PMID:24083888

Carbon Tetrachloride Increases Intracellular Calcium in Rat Liver and Hepatocyte Cultures

Science.gov (United States)

1986-05-12

tible to destruction by CC14 ( Head ~ al., 1981). Thus, the activation of CC14 to a toxic moiety clearly depends upon metabolism by one or more... embryologic development (Wyllie, 1986). In contrast, Toyo-oka et al. (1985) could not establish that phospholipase& or proteases were involved in ischemic...D. M. Bissell, and u. A Meyer. (1977) Drug Metabolism in Adult Rat Hepatocyte& in Primary Monolayer Culture. Gastroenterology 72:1232-1239. Head , B

Intracellular Na+ regulation of Na+ pump sites in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Allen, J.C.; Navran, S.S.; Seidel, C.L.; Dennison, D.K.; Amann, J.M.; Jemelka, S.K.

1989-01-01

Enzymatically dispersed cells from canine saphenous vein and femoral artery were grown in fetal calf serum and studied at day 0 (freshly dispersed) through confluence in primary culture. Intracellular Na levels (Nai), but not intracellular K (Ki), were increased after 24 h in culture and then decreased to a steady state by 4 days. Na+ pump site number [( 3 H] ouabain binding) increased through day 3 and remained elevated. Nai was still elevated at 2 days when the Na+ pump site number began to increase. Total pump turnover (maximum ouabain-inhibited 86 Rb uptake) reflected the increase in Na+ pump site number. These key events precede the observed increases in both protein production and cellular proliferation. If the same cells are maintained in defined medium, without fetal calf serum, Nai, Ki, and the number of [ 3 H]ouabain binding sites do not change with time. These data are consistent with the suggestion that the initial mitogenic response of vascular smooth muscle cells to fetal calf serum involves an increased Na+ influx, and a Nai accumulation, caused by low Na+ pump density. The synthesis of new pump sites effects a decrease in the accumulated Nai, which may be related to cell proliferation

1,25 (OH)2 vitamin D3-induced 45Ca uptake in vascular myocytes cultured from spontaneously hypertensive and normotensive rats

International Nuclear Information System (INIS)

Xue, Hong; McCarron, D.A.; Bukoski, R.D.

1991-01-01

The effect of 1,25 (OH) 2 vitamin D 3 on basal 45 Ca uptake was examined in vasvular smooth muscle cells cultured from mesenteric arteries of spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) normotensive rats. Basal uptake of 45 Ca was significantly greater in myocytes of WKY than SHR at 5, 10, 30 and 60 min incubation with the isotope. Incubation with 1 ng/ml 1,25 (OH) 2 vitamin D 3 for 48 hr increased basal 45 Ca uptake between 1-10 min in SHR and between 5-10 min in WKY. The dose-response relationship indicated that cells from both strains are equally sensitive to the calciotropic effects of 1,25 (OH) 2 vitamin D 3 with half-maximal stimulation occurring at approximately 0.3-0.4 ng/ml. In cells of both strains maximal stimulation of 45 Ca uptake was achieved only after a 12-24 hr period of incubation with hormone and pretreatment with cycloheximide inhibited 1,24 (OH) 2 vitamin D 3 -enhanced 45 Ca uptake. Although 45 Ca binding by extracellular matrix material was significantly greater in WKY than SHR, 1,25 (OH) 2 vitamin D 3 had no effect on the amount of matrix 45 Ca binding in either strain

Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

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W Zhao

2009-03-01

Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p less than 0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

Directory of Open Access Journals (Sweden)

Z Wang

2009-03-01

Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p<0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

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Antonova, L. V., E-mail: antonova.la@mail.ru; Burago, A. Yu.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation); Mironov, A. V. [Kemerovo Cardiology Dispensary, Kemerovo (Russian Federation)

2015-10-27

We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

Inflammation and vascular remodeling in the ventral hippocampus contributes to vulnerability to stress.

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Pearson-Leary, J; Eacret, D; Chen, R; Takano, H; Nicholas, B; Bhatnagar, S

2017-06-27

During exposure to chronic stress, some individuals engage in active coping behaviors that promote resiliency to stress. Other individuals engage in passive coping that is associated with vulnerability to stress and with anxiety and depression. In an effort to identify novel molecular mechanisms that underlie vulnerability or resilience to stress, we used nonbiased analyses of microRNAs in the ventral hippocampus (vHPC) to identify those miRNAs differentially expressed in active (long-latency (LL)/resilient) or passive (short-latency (SL)/vulnerable) rats following chronic social defeat. In the vHPC of active coping rats, miR-455-3p level was increased, while miR-30e-3p level was increased in the vHPC of passive coping rats. Pathway analyses identified inflammatory and vascular remodeling pathways as enriched by genes targeted by these microRNAs. Utilizing several independent markers for blood vessels, inflammatory processes and neural activity in the vHPC, we found that SL/vulnerable rats exhibit increased neural activity, vascular remodeling and inflammatory processes that include both increased blood-brain barrier permeability and increased number of microglia in the vHPC relative to control and resilient rats. To test the relevance of these changes for the development of the vulnerable phenotype, we used pharmacological approaches to determine the contribution of inflammatory processes in mediating vulnerability and resiliency. Administration of the pro-inflammatory cytokine vascular endothelial growth factor-164 increased vulnerability to stress, while the non-steroidal anti-inflammatory drug meloxicam attenuated vulnerability. Collectively, these results show that vulnerability to stress is determined by a re-designed neurovascular unit characterized by increased neural activity, vascular remodeling and pro-inflammatory mechanisms in the vHPC. These results suggest that dampening inflammatory processes by administering anti-inflammatory agents reduces

Maternal exposure to cadmium during gestation perturbs the vascular system of the adult rat offspring

International Nuclear Information System (INIS)

Ronco, Ana Maria; Montenegro, Marcela; Castillo, Paula; Urrutia, Manuel; Saez, Daniel; Hirsch, Sandra; Zepeda, Ramiro; Llanos, Miguel N.

2011-01-01

Several cardiovascular diseases (CVD) observed in adulthood have been associated with environmental influences during fetal growth. Here, we show that maternal exposure to cadmium, a ubiquitously distributed heavy metal and main component of cigarette smoke is able to induce cardiovascular morpho-functional changes in the offspring at adult age. Heart morphology and vascular reactivity were evaluated in the adult offspring of rats exposed to 30 ppm of cadmium during pregnancy. Echocardiographic examination shows altered heart morphology characterized by a concentric left ventricular hypertrophy. Also, we observed a reduced endothelium-dependent reactivity in isolated aortic rings of adult offspring, while endothelium-independent reactivity remained unaltered. These effects were associated with an increase of hem-oxygenase 1 (HO-1) expression in the aortas of adult offspring. The expression of HO-1 was higher in females than males, a finding likely related to the sex-dependent expression of the vascular cell adhesion molecule 1 (VCAM-1), which was lower in the adult female. All these long-term consequences were observed along with normal birth weights and absence of detectable levels of cadmium in fetal and adult tissues of the offspring. In placental tissues however, cadmium levels were detected and correlated with increased NF-κB expression - a transcription factor sensitive to inflammation and oxidative stress - suggesting a placentary mechanism that affect genes related to the development of the cardiovascular system. Our results provide, for the first time, direct experimental evidence supporting that exposure to cadmium during pregnancy reprograms cardiovascular development of the offspring which in turn may conduce to a long term increased risk of CVD.

Kinetic analysis of zinc uptake and serosal transfer by vascularly perfused rat intestine

International Nuclear Information System (INIS)

Hoadley, J.E.; Leinart, A.S.; Cousins, R.J.

1987-01-01

Transport kinetics were examined for uptake of 65 Zn from the lumen and for transport of mucosal 65 Zn subsequent to uptake in the isolated, vascularly perfused intestines of rats fed either a zinc-deficient or zinc-adequate diet. Zinc depletion influenced the intestinal transport of zinc by 1) stimulating a saturable uptake mechanisms, 2) reducing secretion of mucosal 65 Zn into the lumen, and 3) increasing the rate of 65 Zn turnover in a rapidly absorbed mucosal zinc compartment. Uptake of 65 Zn involved both saturable and nonsaturable processes. The saturable process was stimulated by zinc depletion with the apparent maximal transport rate for the saturable mechanism increasing from 60 to 180 nmol Zn x g -1 x 30 min -1 . Most of the 65 Zn taken up was not involved in the short-term secretion or absorption, and mucosal 65 Zn retention was independent of dietary zinc status. Absorption of mucosal 65 Zn was nonsaturable, involved a rapid exchanging zinc compartment, and was stimulated by zinc depletion. The half-life for 65 Zn in this mucosal zinc compartment was ∼ 24 min in the zinc-adequate group and 13 min in the zinc-depleted group

Physiological regulation of extracellular matrix collagen and elastin in the arterial wall of rats by noradrenergic tone and angiotensin II.

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Dab, Houcine; Kacem, Kamel; Hachani, Rafik; Dhaouadi, Nadra; Hodroj, Wassim; Sakly, Mohsen; Randon, Jacques; Bricca, Giampiero

2012-03-01

The interactions between the effects of the sympathetic nervous system (SNS) and angiotensin II (ANG II) on vascular extracellular matrix (ECM) synthesis were determined in rats. The mRNA and protein content of collagen I, collagen III and elastin in the abdominal aorta (AA) and femoral artery (FA) was investigated in Wistar-Kyoto rats treated for 5 weeks with guanethidine, a sympathoplegic, losartan, an ANG II AT1 receptor (AT1R) blocker, or both. The effects of noradrenaline (NE) and ANG II on collagen III and elastin mRNA, and the receptor involved, were tested in cultured vascular smooth muscle cells (VSMCs) in vitro. Guanethidine increased collagen types I and III and decreased elastin, while losartan had an opposite effect, although without effect on collagen III. The combination of treatments abrogated changes induced by simple treatment with collagen I and elastin, but increased collagen III mRNA in AA and not in FA. NE stimulated collagen III mRNA via β receptors and elastin via α1 and α2 receptors. ANG II stimulated collagen III but inhibited elastin mRNA via AT1R. Overall, SNS and ANG II exert opposite and antagonistic effects on major components of ECM in the vascular wall. This may be of relevance for the choice of a therapeutic strategy in vascular diseases.

Effects of 6 weeks oral administration of Phyllanthus acidus leaf water extract on the vascular functions of middle-aged male rats.

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Chongsa, Watchara; Kanokwiroon, Kanyanatt; Jansakul, Chaweewan

2015-12-24

Leaves of Phyllanthus acidus (PA) have been used in Thai traditional medicine for the treatment of hypertension. We have previously shown that chronic treatment of a PA water extract to middle-aged male rats caused a lowering of the body and serum lipids, two of the parameters that are implicated in cardiovascular disease. To investigate if chronic treatment of middle-aged male rats with a PA water extract affected the perivascular (aortic) adipose tissue (PVAT) and/or their vascular functions Fresh leaves of PA were extracted with water and orally gavaged to the middle-aged male rats for 6 weeks. Vascular functions were studied in vitro using isolated thoracic aorta with and without PVAT, and mesenteric rings in Krebs Heinseleit solution with results recorded with a Polygraph or a Myograph system. The amount of blood vessel eNOS and CSE (cystathionine-γ-lyase) expression was measured by Western blotting. PA treatment caused a lower maximal contractile response to phenylephrine (Phe) of the endothelium-intact aortic ring than that of the control group. This effect was abolished by N(G)-nitro-l-arginine (l-NA) or by denudation of the endothelium. dl-propargylglycine (PAG, H2S inhibitor) and TEA (Ca(2+)-activated K(+) channel blocker), but not glybenclamide (ATP-activated K(+) channel blocker), caused a similar increase in the baseline of the endothelium-intact aortic ring in the presence of l-NA in both the PA-treated and control aortic rings. This effect sequentially resulted in a greater contractile response of the aortic rings of both groups to Phe. Glybenclamide also caused a similar increase in the maximal contraction of the endothelium-intact blood vessels with l-NA to both groups. PAG, TEA or glybenclamide did not modify the phenylephrine C-R curves for either group of the PVAT-endothelium-intact aortic rings preincubated with l-NA. The CSE levels of the thoracic aorta and at the PVAT were not different between the PA-treated and the control group

The behavior of the vascular system in the experimental tumor radiotherapy

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Yamaura, H; Matsuzawa, T; Sato, H [Tohoku Univ., Sendai (Japan). Research Inst. for Tuberculosis, Leprosy and Cancer; Ito, Yasuhiko

1975-07-01

The rat ascites hepatoma AH109A transplanted and grown in the rat transparent chamber developed a tumor specific vascular system, the process of which was quantitatively studied because of the vascular length, surface area, and volume per mm/sup 3/ of tissue. The values changed characteristically in each stage of the course. The tumor was irradiated in a chamber with 3000 R of /sup 60/Co ..gamma..-rays, and the tumor cells died leaving behind highly dense capillary networks, which gradually returned to normal level by 7 days after irradiation. The blood vessels, either preformed or newly formed, in the control tissue without tumor were not damaged by this dose. But the proliferation of capillary buds were inhibited slightly with 400 R and completely with 4000 R.

β-adrenergic receptor binding characteristics and responsiveness in cultured Wistar-Kyoto rat arterial smooth muscle cells

International Nuclear Information System (INIS)

Jazayeri, A.; Meyer, W.J. III

1988-01-01

The tone of arterial blood vessels is regulated by the catecholamines through their receptors on arterial smooth muscle cells (ASMC). β- 2 -adrenergic receptors of ASMC mediate vasodilation through agonist mediated c-AMP production. Previous reports have described these receptors on freshly isolated blood vessels. This study demonstrates the presence of β 2 -adrenergic receptors on cultured rat ASMC and that these receptors are functional. β-adrenergic receptor binding was measured using [ 3 H]-dihydroalprenolol (DHA) binding to the membrane of cultured ASMC from normotensive Wistar-Kyoto rats. The ASMC β-adrenergic receptors have a Kd of 0.56 +/- 0.16 nM and a Bmax of 57.2 +/- 21.7 fmol/mg protein. Competition binding studies revealed a much greater affinity of these receptors for epinephrine than norepinephrine, indicating the preponderance of a β 2 -adrenergic receptor subtype. Isoproterenol stimulation of cultured ASMC resulted in a 14 +/- 7 fold increase in intracellular c-AMP content of these cells indicating these receptors are functional. β-adrenergic receptors of cultured ASMC provide an excellent system in which the association between hypertension and observed β-adrenergic receptor differences can be further explored

Insulin-like growth factor-II receptors in cultured rat hepatocytes: regulation by cell density

International Nuclear Information System (INIS)

Scott, C.D.; Baxter, R.C.

1987-01-01

Insulin-like growth factor-II (IGF-II) receptors in primary cultures of adult rat hepatocytes were characterized and their regulation by cell density examined. In hepatocytes cultured at 5 X 10(5) cells per 3.8 cm2 plate [ 125 I]IGF-II bound to specific, high affinity receptors (Ka = 4.4 +/- 0.5 X 10(9) l/mol). Less than 1% cross-reactivity by IGF-I and no cross-reactivity by insulin were observed. IGF-II binding increased when cells were permeabilized with 0.01% digitonin, suggesting the presence of an intracellular receptor pool. Determined by Scatchard analysis and by polyacrylamide gel electrophoresis after affinity labeling, the higher binding was due solely to an increase in binding sites present on 220 kDa type II IGF receptors. In hepatocytes cultured at low densities, the number of cell surface receptors increased markedly, from 10-20,000 receptors per cell at a culture density of 6 X 10(5) cells/well to 70-80,000 receptors per cell at 0.38 X 10(5) cells/well. The increase was not due simply to the exposure of receptors from the intracellular pool, as a density-related increase in receptors was also seen in cells permeabilized with digitonin. There was no evidence that IGF binding proteins, either secreted by hepatocytes or present in fetal calf serum, had any effect on the measurement of receptor concentration or affinity. We conclude that rat hepatocytes in primary culture contain specific IGF-II receptors and that both cell surface and intracellular receptors are regulated by cell density

Electrospinning thermoplastic polyurethane/graphene oxide scaffolds for small diameter vascular graft applications

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Jing, Xin [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Department of Mechanical Engineering, University of Wisconsin–Madison, WI (United States); Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Mi, Hao-Yang [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Salick, Max R. [Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Department of Engineering Physics, University of Wisconsin–Madison, WI (United States); Cordie, Travis M. [Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Department of Biomedical Engineering, University of Wisconsin–Madison, WI (United States); Peng, Xiang-Fang, E-mail: pmxfpeng@scut.edu.cn [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Turng, Lih-Sheng, E-mail: turng@engr.wisc.edu [Department of Mechanical Engineering, University of Wisconsin–Madison, WI (United States); Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States)

2015-04-01

Fabrication of small diameter vascular grafts plays an important role in vascular tissue engineering. In this study, thermoplastic polyurethane (TPU)/graphene oxide (GO) scaffolds were fabricated via electrospinning at different GO contents as potential candidates for small diameter vascular grafts. In terms of mechanical and surface properties, the tensile strength, Young's modulus, and hydrophilicity of the scaffolds increased with an increase of GO content while plasma treatment dramatically improved the scaffold hydrophilicity. Mouse fibroblast (3T3) and human umbilical vein endothelial cells (HUVECs) were cultured on the scaffolds separately to study their biocompatibility and potential to be used as vascular grafts. It was found that cell viability for both types of cells, fibroblast proliferation, and HUVEC attachment were the highest at a 0.5 wt.% GO loading whereas oxygen plasma treatment also enhanced HUVEC viability and attachment significantly. In addition, the suture retention strength and burst pressure of tubular TPU/GO scaffolds containing 0.5 wt.% GO were found to meet the requirements of human blood vessels, and endothelial cells were able to attach to the inner surface of the tubular scaffolds. Platelet adhesion tests using mice blood indicated that vascular scaffolds containing 0.5% GO had low platelet adhesion and activation. Therefore, the electrospun TPU/GO tubular scaffolds have the potential to be used in vascular tissue engineering. - Highlights: • TPU/GO vascular scaffolds were prepared via electrospinning. • The addition of GO improved the modulus and hydrophilicity of the scaffolds. • Fibroblast cell culture verified the scaffolds' biocompatibility. • Endothelial cell culture verified the scaffolds' vascular graft affinity. • The mechanical properties fulfilled the requirements of vascular grafts.

Myostatin, a profibrotic factor and the main inhibitor of striated muscle mass, is present in the penile and vascular smooth muscle.

Science.gov (United States)

Kovanecz, I; Masouminia, M; Gelfand, R; Vernet, D; Rajfer, J; Gonzalez-Cadavid, N F

2017-09-01

Myostatin is present in striated myofibers but, except for myometrial cells, has not been reported within smooth muscle cells (SMC). We investigated in the rat whether myostatin is present in SMC within the penis and the vascular wall and, if so, whether it is transcriptionally expressed and associated with the loss of corporal SMC occurring in certain forms of erectile dysfunction (ED). Myostatin protein was detected by immunohistochemistry/fluorescence and western blots in the perineal striated muscles, and also in the SMC of the penile corpora, arteries and veins, and aorta. Myostatin was found in corporal SMC cultures, and its transcriptional expression (and its receptor) was shown there by DNA microarrays. Myostatin protein was measured by western blots in the penile shaft of rats subjected to bilateral cavernosal nerve resection (BCNR), that were left untreated, or treated (45 days) with muscle-derived stem cells (MDSC), or concurrent daily low-dose sildenafil. Myostatin was not increased by BCNR (compared with sham operated animals), but over expressed after treatment with MDSC. This was reduced by concurrent sildenafil. The presence of myostatin in corporal and vascular SMC, and its overexpression in the corpora by MDSC therapy, may have relevance for the stem cell treatment of corporal fibrosis and ED.

Differential Effects of Three Techniques for Hepatic Vascular Exclusion during Resection for Liver Cirrhosis on Hepatic Ischemia-Reperfusion Injury in Rats

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Changjun Jia

2018-01-01

Full Text Available Background/Aims. Hepatic ischemia-reperfusion (I/R injury is a serious concern during hepatic vascular occlusion. The objectives of this study were to assess effects of three techniques for hepatic vascular occlusion on I/R injury and to explore the underlying mechanisms. Methods. Liver cirrhotic rats had undertaken Pringle maneuver (PR, hemihepatic vascular occlusion (HH, or hepatic blood inflow occlusion without hemihepatic artery control (WH. Levels of tumor necrosis factor alpha (TNF-α, nuclear factor kappa B (NF-κB, toll-like receptor 4 (TLR4, TIR-domain-containing adapter-inducing interferon-β (TRIF, and hemeoxygenase 1 (HMOX1 were assayed. Results. The histopathologic analysis displayed that liver harm was more prominent in the PR group, but similar in the HH and WH groups. The HH and WH groups responded to hepatic I/R inflammation similarly but better than the PR group. Mechanical studies suggested that TNF-α/NF-κB signaling and TLR4/TRIF transduction pathways were associated with the differential effects. In addition, the HH and WH groups had significantly higher levels of hepatic HMOX1 (P<0.05 than the PR group. Conclusions. HH and WH confer better preservation of liver function and protection than the Pringle maneuver in combating I/R injury. Upregulation of HMOX1 may lead to better protection and clinical outcomes after liver resection.

Vitamin C deficiency exerts paradoxical cardiovascular effects in osteogenic disorder Shionogi (ODS) rats.

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Vergely, Catherine; Goirand, Françoise; Ecarnot-Laubriet, Aline; Renard, Céline; Moreau, Daniel; Guilland, Jean-Claude; Dumas, Monique; Rochette, Luc

2004-04-01

Vitamin C is considered to be a very efficient water-soluble antioxidant, for which several new cardiovascular properties were recently described. The aim of this study was to determine in vivo the effects of a severe depletion of vitamin C on cardiac and vascular variables and reperfusion arrhythmias. For this purpose, we used a mutant strain of Wistar rats, osteogenic disorder Shionogi (ODS). After 15 d of consuming a vitamin C-deficient diet, ODS rats had a 90% decrease in plasma and tissue levels of ascorbate compared with ODS vitamin C-supplemented rats and normal Wistar rats. However, plasma antioxidant capacity, proteins, alpha-tocopherol, urate, catecholamines, lipids, and nitrate were not influenced by the vitamin C deficiency in ODS rats. Moreover, there was no difference between ODS vitamin C-deficient and -supplemented rats in heart rate and arterial pressure. After 5 min of an in vivo regional myocardial ischemia, various severe arrhythmias were observed, but their intensities were not modified by vitamin C in vitamin C-deficient ODS rats. The vascular reactivity, measured in vitro on thoracic arteries, was not altered by ascorbate deficiency in ODS rats. These unexpected results suggest that unidentified compensatory mechanisms play a role in maintaining normal cardiac function and vascular reactivity in vitamin C-deficient rats.

Texas Red transport across rat and dogfish shark (Squalus acanthias) choroid plexus.

Science.gov (United States)

Reichel, Valeska; Miller, David S; Fricker, Gert

2008-10-01

Confocal microscopy and image analysis were used to compare driving forces, specificity, and regulation of transport of the fluorescent organic anion, Texas Red (sulforhodamine 101 free acid; TR), in lateral choroid plexus (CP) isolated from rat and an evolutionarily ancient vertebrate, dogfish shark (Squalus acanthias). CP from both species exhibited concentrative, specific, and metabolism-dependent TR transport from bath to subepithelial/vascular space; at steady state, TR accumulation in vascular/subepithelial space was substantially higher than in epithelial cells. In rat CP, steady-state TR accumulation in subepithelial/vascular spaces was reduced by Na(+)-replacement, but was not affected by a 10-fold increase in buffer K(+). In shark CP, Na(+)-replacement did not alter TR accumulation in either tissue compartment; subepithelial/vascular space levels of TR were reduced in high-K(+) medium. In both species, steady-state TR accumulation was not affected by p-aminohippurate or leukotriene C4, suggesting that neither organic anion transporters (SLC22A family) nor multidrug resistance-associated proteins (ABCC family) contributed. In rat CP, digoxin was without effect, indicating that organic anion transporting polypeptide isoform 2 was not involved. Several organic anions reduced cellular and subepithelial/vascular space TR accumulation in both tissues, including estrone sulfate, taurocholate, and the Mrp1 inhibitor MK571. In rat CP, TR accumulation in subepithelial/vascular spaces increased with PKA activation (forskolin), but was not affected by PKC activation (phorbol ester). In shark, neither PKA nor PKC activation specifically affected TR transport. Thus, rat and dogfish shark CP transport TR but do so using different basic mechanisms that respond to different regulatory signals.

Lesion Size Is Exacerbated in Hypoxic Rats Whereas Hypoxia-Inducible Factor-1 Alpha and Vascular Endothelial Growth Factor Increase in Injured Normoxic Rats: A Prospective Cohort Study of Secondary Hypoxia in Focal Traumatic Brain Injury.

Science.gov (United States)

Thelin, Eric Peter; Frostell, Arvid; Mulder, Jan; Mitsios, Nicholas; Damberg, Peter; Aski, Sahar Nikkhou; Risling, Mårten; Svensson, Mikael; Morganti-Kossmann, Maria Cristina; Bellander, Bo-Michael

2016-01-01

Hypoxia following traumatic brain injury (TBI) is a severe insult shown to exacerbate the pathophysiology, resulting in worse outcome. The aim of this study was to investigate the effects of a hypoxic insult in a focal TBI model by monitoring brain edema, lesion volume, serum biomarker levels, immune cell infiltration, as well as the expression of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF). Female Sprague-Dawley rats (n = 73, including sham and naive) were used. The rats were intubated and mechanically ventilated. A controlled cortical impact device created a 3-mm deep lesion in the right parietal hemisphere. Post-injury, rats inhaled either normoxic (22% O2) or hypoxic (11% O2) mixtures for 30 min. The rats were sacrificed at 1, 3, 7, 14, and 28 days post-injury. Serum was collected for S100B measurements using ELISA. Ex vivo magnetic resonance imaging (MRI) was performed to determine lesion size and edema volume. Immunofluorescence was employed to analyze neuronal death, changes in cerebral macrophage- and neutrophil infiltration, microglia proliferation, apoptosis, complement activation (C5b9), IgG extravasation, HIF-1α, and VEGF. The hypoxic group had significantly increased blood levels of lactate and decreased pO2 (p hypoxic animals (p hypoxic group at 1 day after trauma (p = 0.0868). No differences were observed between the groups in cytotoxic and vascular edema, IgG extravasation, neutrophils and macrophage aggregation, microglia proliferation, or C5b-9 expression. Hypoxia following focal TBI exacerbated the lesion size and neuronal loss. Moreover, there was a tendency to higher levels of S100B in the hypoxic group early after injury, indicating a potential validity as a biomarker of injury severity. In the normoxic group, the expression of HIF-1α and VEGF was found elevated, possibly indicative of neuro-protective responses occurring in this less severely injured group. Further studies are

Akt1/PKB upregulation leads to vascular smooth muscle cell hypertrophy and polyploidization

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Hixon, Mary L.; Muro-Cacho, Carlos; Wagner, Mark W.; Obejero-Paz, Carlos; Millie, Elise; Fujio, Yasushi; Kureishi, Yasuko; Hassold, Terry; Walsh, Kenneth; Gualberto, Antonio

2000-01-01

Vascular smooth muscle cells (VSMCs) at capacitance arteries of hypertensive individuals and animals undergo marked age- and blood pressure–dependent polyploidization and hypertrophy. We show here that VSMCs at capacitance arteries of rat models of hypertension display high levels of Akt1/PKB protein and activity. Gene transfer of Akt1 to VSMCs isolated from a normotensive rat strain was sufficient to abrogate the activity of the mitotic spindle cell–cycle checkpoint, promoting polyploidization and hypertrophy. Furthermore, the hypertrophic agent angiotensin II induced VSMC polyploidization in an Akt1-dependent manner. These results demonstrate that Akt1 regulates ploidy levels in VSMCs and contributes to vascular smooth muscle polyploidization and hypertrophy during hypertension. PMID:11032861

Alterações vasculares em ratos obesos por dieta rica em gordura: papel da Via L-arginina/NO Endotelial Alteraciones vasculares en ratones obesos por dieta rica en grasa: papel de la vía L-arginina/NO endotelial Vascular alterations in high-fat diet-obese rats: role of Endothelial L-arginine/NO Pathway

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Thiago Bruder Nascimento

2011-07-01

perfiles metabólicos y endocrinos de los animales. Fueron obtenidas las curvas para noradrelanina en ausencia y en presencia del inhibidor de óxido nítrico sintasa (L-NAME, 3x10-4M, en la aorta torácica intacta y con denudación de los ratones C y OB. RESULTADOS: Las medidas de peso corporal, índice de adiposidad, leptina e insulina aumentaron en los ratones OB, mientras que la presión arterial permaneció inalterada. La obesidad también produjo una tolerancia a la glucosa y una resistencia a la insulina. La reactividad a la noradrenalina de la aorta intacta fue similar en los ratones C y OB. La presencia de L-NAME generó un aumento similar en las respuestas máximas, pero una desviación mayor a la izquierda de las respuestas en las aortas intactas de los ratones C con relación a los ratones OB [EC50 (x10-7M: C = 1,84 (0,83-4,07, O = 2,49 (1,41-4,38; presencia de L-NAME C = 0,02 (0,01-0,04*, O = 0,21 (0,11-0,40*†,*p BACKGROUND: Mechanisms underlying vascular abnormalities in obesity remain to be completely clarified. OBJECTIVE: L-arginine/nitric oxide pathway was evaluated on vascular response of high-fat diet-obese rats, focusing on endothelial and smooth muscle cells. METHODS: 30-day-old rats were divided in two groups: control (C and obese (OB, high-fat diet for 30 weeks. After 30 weeks, body weight, adiposity index, blood pressure, and metabolic and endocrine profiles of the animals were recorded. Curves to noradrenaline were obtained in absence and presence of nitric oxide synthase inhibitor (L-NAME, 3x10-4M on intact and denuded thoracic aorta from C and OB rats. RESULTS: Body weight, adiposity index, leptin and insulin levels were increased in OB, while blood pressure was unchanged. Obesity also produced glucose tolerance and insulin resistance. Reactivity to noradrenaline of intact aorta was similar in C and OB rats. L-NAME presence produced a similar increase in maximal responses, but a higher leftward shift of noradrenaline responses in intact aorta

Feasibility of direct oxygenation of primary-cultured rat hepatocytes using polyethylene glycol-decorated liposome-encapsulated hemoglobin (LEH).

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Naruto, Hirosuke; Huang, Hongyun; Nishikawa, Masaki; Kojima, Nobuhiko; Mizuno, Atsushi; Ohta, Katsuji; Sakai, Yasuyuki

2007-10-01

We tested the short-term efficacy of liposome-encapsulated hemoglobin (LEH) in cultured rat hepatocytes. Supplementation with LEH (20% of the hemoglobin concentration of blood) did not lower albumin production in static culture, and completely reversed the cell death and deterioration in albumin production caused by an oxygen shortage in 2D flat-plate perfusion bioreactors.

An improved in vitro blood-brain barrier model: rat brain endothelial cells co-cultured with astrocytes.

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Abbott, N Joan; Dolman, Diana E M; Drndarski, Svetlana; Fredriksson, Sarah M

2012-01-01

In vitro blood-brain barrier (BBB) models using primary cultured brain endothelial cells are important for establishing cellular and molecular mechanisms of BBB function. Co-culturing with BBB-associated cells especially astrocytes to mimic more closely the in vivo condition leads to upregulation of the BBB phenotype in the brain endothelial cells. Rat brain endothelial cells (RBECs) are a valuable tool allowing ready comparison with in vivo studies in rodents; however, it has been difficult to obtain pure brain endothelial cells, and few models achieve a transendothelial electrical resistance (TEER, measure of tight junction efficacy) of >200 Ω cm(2), i.e. the models are still relatively leaky. Here, we describe methods for preparing high purity RBECs and neonatal rat astrocytes, and a co-culture method that generates a robust, stable BBB model that can achieve TEER >600 Ω cm(2). The method is based on >20 years experience with RBEC culture, together with recent improvements to kill contaminating cells and encourage BBB differentiation.Astrocytes are isolated by mechanical dissection and cell straining and are frozen for later co-culture. RBECs are isolated from 3-month-old rat cortices. The brains are cleaned of meninges and white matter and enzymatically and mechanically dissociated. Thereafter, the tissue homogenate is centrifuged in bovine serum albumin to separate vessel fragments from other cells that stick to the myelin plug. The vessel fragments undergo a second enzyme digestion to separate pericytes from vessels and break down vessels into shorter segments, after which a Percoll gradient is used to separate capillaries from venules, arterioles, and single cells. To kill remaining contaminating cells such as pericytes, the capillary fragments are plated in puromycin-containing medium and RBECs grown to 50-60% confluence. They are then passaged onto filters for co-culture with astrocytes grown in the bottom of the wells. The whole procedure takes ∼2

NONOates regulate KCl cotransporter-1 and -3 mRNA expression in vascular smooth muscle cells.

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Di Fulvio, Mauricio; Lauf, Peter K; Shah, Shalin; Adragna, Norma C

2003-05-01

Nitric oxide (NO) donors regulate KCl cotransport (KCC) activity and cotransporter-1 and -3 (KCC1 and KCC3) mRNA expression in sheep erythrocytes and in primary cultures of rat vascular smooth muscle cells (VSMCs), respectively. In this study, we used NONOates as rapid and slow NO releasers to provide direct evidence implicating NO as a regulator of KCC3 gene expression at the mRNA level. In addition, we used the expression of KCC3 mRNA to further investigate the mechanism of action of these NO donors at the cellular level. Treatment of VSMCs with rapid NO releasers, like NOC-5 and NOC-9, as well as with the direct NO-independent soluble guanylyl cyclase (sGC) stimulator YC-1, acutely increased KCC3 mRNA expression in a concentration- and time-dependent manner. The slow NO releaser NOC-18 had no effect on KCC3 gene expression. A specific NO scavenger completely prevented the NONOate-induced KCC3 mRNA expression. Inhibition of sGC with LY-83583 blocked the NONOate- and YC-1-induced KCC3 mRNA expression. This study shows that in primary cultures of rat VSMCs, the fast NO releasers NOC-9 and NOC-5, but not the slow NO releaser NOC-18, acutely upregulate KCC3 mRNA expression in a NO/sGC-dependent manner.

Α-Melanocyte-Stimulating Hormone Protects Early Diabetic Retina from Blood-Retinal Barrier Breakdown and Vascular Leakage via MC4R.

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Cai, Siwei; Yang, Qianhui; Hou, Mengzhu; Han, Qian; Zhang, Hanyu; Wang, Jiantao; Qi, Chen; Bo, Qiyu; Ru, Yusha; Yang, Wei; Gu, Zhongxiu; Wei, Ruihua; Cao, Yunshan; Li, Xiaorong; Zhang, Yan

2018-01-01

Blood-retinal barrier (BRB) breakdown and vascular leakage is the leading cause of blindness of diabetic retinopathy (DR). Hyperglycemia-induced oxidative stress and inflammation are primary pathogenic factors of this severe DR complication. An effective interventional modality against the pathogenic factors during early DR is needed to curb BRB breakdown and vascular leakage. This study sought to examine the protective effects of α-Melanocyte-stimulating hormone (α-MSH) on early diabetic retina against vascular hyperpermeability, electrophysiological dysfunction, and morphological deterioration in a rat model of diabetes and probe the mechanisms underlying the α-MSH's anti-hyperpermeability in both rodent retinas and simian retinal vascular endothelial cells (RF6A). Sprague Dawley rats were injected through tail vein with streptozotocin to induce diabetes. The rats were intravitreally injected with α-MSH or saline at Week 1 and 3 after hyperglycemia. In another 2 weeks, Evans blue assay, transmission electron microscopy, electroretinogram (ERG), and hematoxylin and eosin (H&E) staining were performed to examine the protective effects of α-MSH in diabetic retinas. The expression of pro-inflammatory factors and tight junction at mRNA and protein levels in retinas was analyzed. Finally, the α-MSH's anti-hyperpermeability was confirmed in a high glucose (HG)-treated RF6A cell monolayer transwell culture by transendothelial electrical resistance (TEER) measurement and a fluorescein isothiocyanate-Dextran assay. Universal or specific melanocortin receptor (MCR) blockers were also employed to elucidate the MCR subtype mediating α-MSH's protection. Evans blue assay showed that BRB breakdown and vascular leakage was detected, and rescued by α-MSH both qualitatively and quantitatively in early diabetic retinas; electron microscopy revealed substantially improved retinal and choroidal vessel ultrastructures in α-MSH-treated diabetic retinas; scotopic ERG suggested

A Robust Method to Generate Mechanically Anisotropic Vascular Smooth Muscle Cell Sheets for Vascular Tissue Engineering.

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Backman, Daniel E; LeSavage, Bauer L; Shah, Shivem B; Wong, Joyce Y

2017-06-01

In arterial tissue engineering, mimicking native structure and mechanical properties is essential because compliance mismatch can lead to graft failure and further disease. With bottom-up tissue engineering approaches, designing tissue components with proper microscale mechanical properties is crucial to achieve the necessary macroscale properties in the final implant. This study develops a thermoresponsive cell culture platform for growing aligned vascular smooth muscle cell (VSMC) sheets by photografting N-isopropylacrylamide (NIPAAm) onto micropatterned poly(dimethysiloxane) (PDMS). The grafting process is experimentally and computationally optimized to produce PNIPAAm-PDMS substrates optimal for VSMC attachment. To allow long-term VSMC sheet culture and increase the rate of VSMC sheet formation, PNIPAAm-PDMS surfaces were further modified with 3-aminopropyltriethoxysilane yielding a robust, thermoresponsive cell culture platform for culturing VSMC sheets. VSMC cell sheets cultured on patterned thermoresponsive substrates exhibit cellular and collagen alignment in the direction of the micropattern. Mechanical characterization of patterned, single-layer VSMC sheets reveals increased stiffness in the aligned direction compared to the perpendicular direction whereas nonpatterned cell sheets exhibit no directional dependence. Structural and mechanical anisotropy of aligned, single-layer VSMC sheets makes this platform an attractive microstructural building block for engineering a vascular graft to match the in vivo mechanical properties of native arterial tissue. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chronic Stress Improves NO- and Ca2+ Flux-Dependent Vascular Function: A Pharmacological Study

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Bruder-Nascimento, Thiago, E-mail: bruderthiago@usp.br [Departamento de Farmacologia - Instituto de Biociências de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil); Departamento de Clínica Médica - Faculdade de Medicina de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil); Campos, Dijon Henrique Salome [Departamento de Clínica Médica - Faculdade de Medicina de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil)

2015-03-15

Stress is associated with cardiovascular diseases. This study aimed at assessing whether chronic stress induces vascular alterations, and whether these modulations are nitric oxide (NO) and Ca2+ dependent. Wistar rats, 30 days of age, were separated into 2 groups: control (C) and Stress (St). Chronic stress consisted of immobilization for 1 hour/day, 5 days/week, 15 weeks. Systolic blood pressure was assessed. Vascular studies on aortic rings were performed. Concentration-effect curves were built for noradrenaline, in the presence of L-NAME or prazosin, acetylcholine, sodium nitroprusside and KCl. In addition, Ca{sup 2+} flux was also evaluated. Chronic stress induced hypertension, decreased the vascular response to KCl and to noradrenaline, and increased the vascular response to acetylcholine. L-NAME blunted the difference observed in noradrenaline curves. Furthermore, contractile response to Ca{sup 2+} was decreased in the aorta of stressed rats. Our data suggest that the vascular response to chronic stress is an adaptation to its deleterious effects, such as hypertension. In addition, this adaptation is NO- and Ca{sup 2+}-dependent. These data help to clarify the contribution of stress to cardiovascular abnormalities. However, further studies are necessary to better elucidate the mechanisms involved in the cardiovascular dysfunction associated with stressors. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0)

Upregulation of Klotho potentially inhibits pulmonary vascular remodeling by blocking the activation of the Wnt signaling pathway in rats with PM2.5-induced pulmonary arterial hypertension.

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Cong, Lu-Hong; Du, Shi-Yu; Wu, Yi-Na; Liu, Ying; Li, Tao; Wang, Hui; Li, Gang; Duan, Jun

2018-01-30

We evaluated the effects of Klotho on pulmonary vascular remodeling and cell proliferation and apoptosis in rat models with PM2.5-induced pulmonary arterial hypertension (PAH) via the Wnt signaling pathway. After establishing rat models of PM2.5-induced PAH, these Sprague-Dawley male rats were randomized into control and model groups. Cells extracted from the model rats were sub-categorized into different groups. Activation of Wnt/β-catenin signaling transcription factor was detected by a TOPFlash/FOPFlash assay. A serial of experiment was conducted to identify the mechanism of Klotho on PHA via the Wnt signaling pathway. VEGF levels and PaCO 2 content were higher in the model group, while PaO 2, NO 2 - /NO 3 - content and Klotho level was lower compared to the control group. In comparison to the control group, the model group had decreased Klotho and Bax levels, and elevated Wnt-1, β-catenin, bcl-2, survivin, and PCNA expression, VEGF, IL-6, TNF-α, TNF-β1, and bFGF levels, as well as the percentage of pulmonary artery ring contraction. The Klotho vector, DKK-1 and DKK-1 + Klotho vector groups exhibited reduced cell proliferation, luciferase activity, and the expression of Wnt-1, β-catenin, bcl-2, survivin, and PCNA, as well as shortened S phase compared with the blank and NC groups. Compared with the Klotho vector and DKK-1 groups, the DKK-1 + Klotho vector groups had reduced cell proliferation, luciferase activity, and the expression of Wnt-1, β-catenin, bcl-2, survivin, and PCNA, as well as a shortened S phase. Conclusively, Klotho inhibits pulmonary vascular remodeling by inactivation of Wnt signaling pathway. © 2018 Wiley Periodicals, Inc.

DWI and complex brain network analysis predicts vascular cognitive impairment in spontaneous hypertensive rats undergoing executive function tests

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Xavier eLópez-Gil

2014-07-01

Full Text Available The identification of biomarkers of vascular cognitive impairment is urgent for its early diagnosis. The aim of this study was to detect and monitor changes in brain structure and connectivity, and to correlate them with the decline in executive function. We examined the feasibility of early diagnostic magnetic resonance imaging to predict cognitive impairment before onset in an animal model of chronic hypertension: Spontaneously Hypertensive Rats. Cognitive performance was tested in an operant conditioning paradigm that evaluated learning, memory and behavioral flexibility skills. Behavioral tests were coupled with longitudinal diffusion weighted imaging acquired with 126 diffusion gradient directions and 0.3 mm3 isometric resolution at 10, 14, 18, 22, 26 and 40 weeks after birth. Diffusion weighted imaging was analyzed in 2 different ways, by regional characterization of diffusion tensor imaging indices, and by assessing changes in structural brain network organization based on Q-Ball tractography. Already at the first evaluated times, diffusion tensor imaging scalar maps revealed significant differences in many regions, suggesting loss of integrity in white and grey matter of spontaneously hypertensive rats when compared to normotensive control rats. In addition, graph theory analysis of the structural brain network demonstrated a significant decrease of hierarchical modularity, global and local efficacy, with predictive value as shown by regional 3-fold cross validation study. Moreover, these decreases were significantly correlated with the behavioral performance deficits observed at subsequent time points, suggesting that the diffusion weighted imaging and connectivity studies can unravel neuroimaging alterations even overt signs of cognitive impairment become apparent.

Contrasting Nephropathic Responses to Oral Administration of Extract of Cultured Penicillium polonicum in Rat and Primate

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John E. Fincham

2010-08-01

Full Text Available Liquid- or solid substrate-cultured Penicillium polonicum administered in feed to rats over several days evokes a histopathological response in kidney involving apoptosis and abnormal mitosis in proximal tubules. The amphoteric toxin is yet only partly characterized, but can be isolated from cultured sporulating biomass in a fraction that is soluble in water and ethanol, and exchangeable on either anion- or cation-exchange resins. After several weeks of treatment renal proximal tubule distortion became striking on account of karyocytomegaly, but even treatment for nearly two years remained asymptomatic. Extract from a batch of solid substrate fermentation of P. polonicum on shredded wheat was incorporated into feed for rats during four consecutive days, and also given as an aqueous solution by oral gavage to a vervet monkey daily for 10 days. Treatment was asymptomatic for both types of animal. Rat response was evident as the typical renal apoptosis and karyomegaly. In contrast there was no such response in the primate; and neither creatinine clearance nor any haematological characteristic or serum component concentration deviated from a control or from historical data for this primate. The contrast is discussed concerning other negative findings for P. polonicum in pigs and hamsters. Renal karyomegaly, as a common rat response to persistent exposure to ochratoxin A, is not known in humans suspected as being exposed to more than the usual trace amounts of dietary ochratoxin A. Therefore the present findings question assumptions that human response to ochratoxin A conforms to that in the rat.

Blood Vessel-Derived Acellular Matrix for Vascular Graft Application

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Luigi Dall’Olmo

2014-01-01

Full Text Available To overcome the issues connected to the use of autologous vascular grafts and artificial materials for reconstruction of small diameter (<6 mm blood vessels, this study aimed to develop acellular matrix- (AM- based vascular grafts. Rat iliac arteries were decellularized by a detergent-enzymatic treatment, whereas endothelial cells (ECs were obtained through enzymatic digestion of rat skin followed by immunomagnetic separation of CD31-positive cells. Sixteen female Lewis rats (8 weeks old received only AM or previously in vitro reendothelialized AM as abdominal aorta interposition grafts (about 1 cm. The detergent-enzymatic treatment completely removed the cellular part of vessels and both MHC class I and class II antigens. One month after surgery, the luminal surface of implanted AMs was partially covered by ECs and several platelets adhered in the areas lacking cell coverage. Intimal hyperplasia, already detected after 1 month, increased at 3 months. On the contrary, all grafts composed by AM and ECs were completely covered at 1 month and their structure was similar to that of native vessels at 3 months. Taken together, our findings show that prostheses composed of AM preseeded with ECs could be a promising approach for the replacement of blood vessels.

Effects of nonhypotensive endotoxemia in conscious rats: Role of prostaglandins

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Burnier, M.; Waeber, B.; Aubert, J.F.; Nussberger, J.; Brunner, H.R.

1988-01-01

A nonhypotensive dose of endotoxin was administered to normal conscious rats to evaluate the vascular and humoral effects of endotoxemia per se. Mean blood pressure and heart rate remained stable during the 45 min infusion of Escherichia coli endotoxin. However, a marked increase in plasma renin activity plasma epinephrine and plasma norepinephrine was observed during infusion in endotoxin-treated rats when compared with the vehicle-treated animals. In addition, the blood pressure response to exogenous norepinephrine was significantly reduced during nonhypotensive endotoxemia. Significant changes in regional blood flow distribution, as assessed by radiolabeled microspheres, were observed in endotoxemic rats; in particular a decrease in renal blood flow, and an increase in coronary blood flow were found. The role of prostaglandins in the vascular and humoral alterations induced by nonhypotensive endotoxemia was also examined. Pretreatment with indomethacin (5 mg) prevent the increase in plasma renin activity as well as plasma catecholamine levels. On the contrary, the decreased vascular reactivity and the reduction in renal blood flow observed during endotoxemia were not affected by prostaglandin synthesis inhibition. Thus significant vascular and humoral changes have been found during endotoxemia even in absence of hypotension. The humoral but not the vascular effects of endotoxemia were abolished when prostaglandin synthesis was inhibited

Post-Weaning Protein Malnutrition Increases Blood Pressure and Induces Endothelial Dysfunctions in Rats

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Siman, Fabiana D. M.; Silveira, Edna A.; Meira, Eduardo F.; da Costa, Carlos P.; Vassallo, Dalton V.; Padilha, Alessandra S.

2012-01-01

Malnutrition during critical periods in early life may increase the subsequent risk of hypertension and metabolic diseases in adulthood, but the underlying mechanisms are still unclear. We aimed to evaluate the effects of post-weaning protein malnutrition on blood pressure and vascular reactivity in aortic rings (conductance artery) and isolated-perfused tail arteries (resistance artery) from control (fed with Labina®) and post-weaning protein malnutrition rats (offspring that received a diet with low protein content for three months). Systolic and diastolic blood pressure and heart rate increased in the post-weaning protein malnutrition rats. In the aortic rings, reactivity to phenylephrine (10−10–3.10−4 M) was similar in both groups. Endothelium removal or L-NAME (10−4 M) incubation increased the response to phenylephrine, but the L-NAME effect was greater in the aortic rings from the post-weaning protein malnutrition rats. The protein expression of the endothelial nitric oxide isoform increased in the aortic rings from the post-weaning protein malnutrition rats. Incubation with apocynin (0.3 mM) reduced the response to phenylephrine in both groups, but this effect was higher in the post-weaning protein malnutrition rats, suggesting an increase of superoxide anion release. In the tail artery of the post-weaning protein malnutrition rats, the vascular reactivity to phenylephrine (0.001–300 µg) and the relaxation to acetylcholine (10−10–10−3 M) were increased. Post-weaning protein malnutrition increases blood pressure and induces vascular dysfunction. Although the vascular reactivity in the aortic rings did not change, an increase in superoxide anion and nitric oxide was observed in the post-weaning protein malnutrition rats. However, in the resistance arteries, the increased vascular reactivity may be a potential mechanism underlying the increased blood pressure observed in this model. PMID:22529948

Enhanced expression of contractile endothelin ET(B) receptors in rat coronary artery after organ culture

DEFF Research Database (Denmark)

Johnsson, E.; Maddahi, A.; Wackenfors, A.

2008-01-01

. In cardiovascular disease and in organ culture in vitro, endothelin ET(B) receptors are up-regulated on smooth muscle cells. The objectives of the present study were to characterise the endothelin receptor-induced vasoconstriction and quantify the endothelin receptor mRNA levels and immunoreactivity in fresh...... and cultured rat coronary arteries. We demonstrate that endothelin-1 induces strong and equal concentration-dependent contractions in fresh and cultured segments from the left anterior descending coronary artery. Sarafotoxin 6c, an endothelin ET(B) receptor agonist, had negligible effect in fresh arteries...... but produced significant vasoconstriction after organ culture. The endothelin ET(B) receptor mRNA level and the receptor protein immunoreactivity were increased, whereas the level of endothelin ET(A) receptor mRNA was down-regulated but not its receptor protein immunoreactivity after organ culture...

Computational analysis of integrated biosensing and shear flow in a microfluidic vascular model

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Wong, Jeremy F.; Young, Edmond W. K.; Simmons, Craig A.

2017-11-01

Fluid flow and flow-induced shear stress are critical components of the vascular microenvironment commonly studied using microfluidic cell culture models. Microfluidic vascular models mimicking the physiological microenvironment also offer great potential for incorporating on-chip biomolecular detection. In spite of this potential, however, there are few examples of such functionality. Detection of biomolecules released by cells under flow-induced shear stress is a significant challenge due to severe sample dilution caused by the fluid flow used to generate the shear stress, frequently to the extent where the analyte is no longer detectable. In this work, we developed a computational model of a vascular microfluidic cell culture model that integrates physiological shear flow and on-chip monitoring of cell-secreted factors. Applicable to multilayer device configurations, the computational model was applied to a bilayer configuration, which has been used in numerous cell culture applications including vascular models. Guidelines were established that allow cells to be subjected to a wide range of physiological shear stress while ensuring optimal rapid transport of analyte to the biosensor surface and minimized biosensor response times. These guidelines therefore enable the development of microfluidic vascular models that integrate cell-secreted factor detection while addressing flow constraints imposed by physiological shear stress. Ultimately, this work will result in the addition of valuable functionality to microfluidic cell culture models that further fulfill their potential as labs-on-chips.

Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets.

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Lee, Yun Jung; Choi, Deok Ho; Cho, Guk Hyun; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

2012-08-06

Arctium lappa L. (Asteraceae), burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL) seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD). EAL-I (100 mg·kg-1/day), EAL-II (200 mg·kg-1/day), and fluvastatin (3 mg·kg-1/day) groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks. Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL) in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh)-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP) and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP)-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model. The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.

Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets

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Lee Yun

2012-08-01

Full Text Available Abstract Background Arctium lappa L. (Asteraceae, burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD. Method EAL-I (100 mg·kg−1/day, EAL-II (200 mg·kg−1/day, and fluvastatin (3 mg·kg−1/day groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks. Results Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM-1, vascular cell adhesion molecule (VCAM-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model. Conclusion The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.

Losartan attenuates chronic cigarette smoke exposure-induced pulmonary arterial hypertension in rats: Possible involvement of angiotensin-converting enzyme-2

International Nuclear Information System (INIS)

Han Suxia; He Guangming; Wang Tao; Chen Lei; Ning Yunye; Luo Feng; An Jin; Yang Ting; Dong Jiajia; Liao Zenglin; Xu Dan; Wen Fuqiang

2010-01-01

Chronic cigarette smoking induces pulmonary arterial hypertension (PAH) by largely unknown mechanisms. Renin-angiotensin system (RAS) is known to function in the development of PAH. Losartan, a specific angiotensin II receptor antagonist, is a well-known antihypertensive drug with a potential role in regulating angiotensin-converting enzyme-2 (ACE2), a recently found regulator of RAS. To determine the effect of losartan on smoke-induced PAH and its possible mechanism, rats were daily exposed to cigarette smoke for 6 months in the absence and in the presence of losartan. Elevated right ventricular systolic pressure (RVSP), thickened wall of pulmonary arteries with apparent medial hypertrophy along with increased angiotensin II (Ang II) and decreased ACE2 levels were observed in smoke-exposed-only rats. Losartan administration ameliorated pulmonary vascular remodeling, inhibited the smoke-induced RVSP and Ang II elevation and partially reversed the ACE2 decrease in rat lungs. In cultured primary pulmonary artery smooth muscle cells (PASMCs) from 3- and 6-month smoke-exposed rats, ACE2 levels were significantly lower than in those from the control rats. Moreover, PASMCs from 6-month exposed rats proliferated more rapidly than those from 3-month exposed or control rats, and cells grew even more rapidly in the presence of DX600, an ACE2 inhibitor. Consistent with the in vivo study, in vitro losartan pretreatment also inhibited cigarette smoke extract (CSE)-induced cell proliferation and ACE2 reduction in rat PASMCs. The results suggest that losartan may be therapeutically useful in the chronic smoking-induced pulmonary vascular remodeling and PAH and ACE2 may be involved as part of its mechanism. Our study might provide insight into the development of new therapeutic interventions for PAH smokers.

The Risk Evaluation of Tungsten Oxide Nanoparticles in Cultured Rat Liver Cells for Its Safe Applications in Nanotechnology

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Hasan Turkez

2014-08-01

Full Text Available Tungsten (VI oxide (WO3 nanoparticles (NPs are used for many industrial purposes in everyday life. However, their effects on human health have not been sufficiently evaluated. Therefore, the present study was designed to investigate the toxicity potentials of various concentrations (0 to 1000 ppm of WO3NPs (<100 nm particle size in cultured primary rat hepatocytes. The results of cell viability assay showed that the higher concentrations of dispersed WO3 NPs (300, 500 and 1000 ppm caused significant (p<0.05 decreases of cell viability. Also, dose dependent negative alterations were observed in oxidative status and antioxidant capacity levels after the application of WO3 in cultured rat primary hepatocytes. The results of genotoxicity tests revealed that these NPs did not cause significant increases of micronucleated hepatocytes (MNHEPs but increased 8-oxo-2-deoxyguanosine (8-OH-dG levels as compared to the control culture.

Review of Surgical Techniques of Experimental Renal Transplantation in Rats.

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Shrestha, Badri; Haylor, John

2017-08-01

Microvascular surgical techniques of renal transplant in rats have evolved over the past 5 decades to achieve successful rat renal transplant; these modifications have included surgical techniques to address the anatomic variations in the renal blood vessels and those to reduce ischemic and operation durations. Here, we review the surgical techniques of renal transplant in rats and evaluate the advantages and disadvantages of individual techniques of vascular and ureteric anastomoses. For this review, we performed a systematic literature search using relevant medical subject heading terms and included appropriate publications in the review. Since the first description of a rat model of renal transplant by Bernard Fisher and his colleagues in 1965, which used end-to-side anastomosis between the renal vein and renal artery to the recipient inferior vena cava and aorta, several vascular and ureteric anastomosis techniques have been modified. Vascular anastomosis techniques now include end-to-end anastomosis, use of donor aortic and inferior vena cava conduits, sleeve and cuff anastomoses, and application of fibrin glue. Likewise, restoration of the urinary tract can now be achieved by direct anastomosis of the donor ureter to the recipient bladder, end-to-end anastomosis between the donor and recipient ureters, and donor bladder cuff to the recipient bladder. There are advantages and disadvantages attributable to individual techniques. The range of vascular and ureteric anastomosis techniques that has emerged reflects the need for mastering more than one technique to suit the vascular anatomy of individual animals and to reduce operating time for achieving successful outcomes after renal transplant.

Nifedipine-activated Ca(2+) permeability in newborn rat cortical collecting duct cells in primary culture.

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Valencia, L; Bidet, M; Martial, S; Sanchez, E; Melendez, E; Tauc, M; Poujeol, C; Martin, D; Namorado, M D; Reyes, J L; Poujeol, P

2001-05-01

To characterize Ca(2+) transport in newborn rat cortical collecting duct (CCD) cells, we used nifedipine, which in adult rat distal tubules inhibits the intracellular Ca(2+) concentration ([Ca(2+)](i)) increase in response to hormonal activation. We found that the dihydropyridine (DHP) nifedipine (20 microM) produced an increase in [Ca(2+)](i) from 87.6 +/- 3.3 nM to 389.9 +/- 29.0 nM in 65% of the cells. Similar effects of other DHP (BAY K 8644, isradipine) were also observed. Conversely, DHPs did not induce any increase in [Ca(2+)](i) in cells obtained from proximal convoluted tubule. In CCD cells, neither verapamil nor diltiazem induced any rise in [Ca(2+)](i). Experiments in the presence of EGTA showed that external Ca(2+) was required for the nifedipine effect, while lanthanum (20 microM), gadolinium (100 microM), and diltiazem (20 microM) inhibited the effect. Experiments done in the presence of valinomycin resulted in the same nifedipine effect, showing that K(+) channels were not involved in the nifedipine-induced [Ca(2+)](i) rise. H(2)O(2) also triggered [Ca(2+)](i) rise. However, nifedipine-induced [Ca(2+)](i) increase was not affected by protamine. In conclusion, the present results indicate that 1) primary cultures of cells from terminal nephron of newborn rats are a useful tool for investigating Ca(2+) transport mechanisms during growth, and 2) newborn rat CCD cells in primary culture exhibit a new apical nifedipine-activated Ca(2+) channel of capacitive type (either transient receptor potential or leak channel).

Non-invasive detection and quantification of brain microvascular deficits by near-infrared spectroscopy in a rat model of Vascular Cognitive Impairment

Science.gov (United States)

Hallacoglu, Bertan; Sassaroli, Angelo M.; Rosenberg, Irwin H.; Troen, Aron; Fantini, Sergio

2011-02-01

Structural abnormalities in brain microvasculature are commonly associated with Alzheimer's Disease and other dementias. However, the extent to which structural microvascular abnormalities cause functional impairments in brain circulation and thereby to cognitive impairment is unclear. Non-invasive, near-infrared spectroscopy (NIRS) methods can be used to determine the absolute hemoglobin concentration and saturation in brain tissue, from which additional parameters such as cerebral blood volume (a theoretical correlate of brain microvascular density) can be derived. Validating such NIRS parameters in animal models, and understanding their relationship to cognitive function is an important step in the ultimate application of these methods to humans. To this end we applied a non-invasive multidistance NIRS method to determine the absolute concentration and saturation of cerebral hemoglobin in rat, by separately measuring absorption and reduced scattering coefficients without relying on pre- or post-correction factors. We applied this method to study brain circulation in folate deficient rats, which express brain microvascular pathology1 and which we have shown to develop cognitive impairment.2 We found absolute brain hemoglobin concentration ([HbT]) and oxygen saturation (StO2) to be significantly lower in folate deficient rats (n=6) with respect to control rats (n=5) (for [HbT]: 73+/-10 μM vs. 95+/-14 μM for StO2: 55%+/-7% vs. 66% +/-4%), implicating microvascular pathology and diminished oxygen delivery as a mechanism of cognitive impairment. More generally, our study highlights how noninvasive, absolute NIRS measurements can provide unique insight into the pathophysiology of Vascular Cognitive Impairment. Applying this method to this and other rat models of cognitive impairment will help to validate physiologically meaningful NIRS parameters for the ultimate goal of studying cerebral microvascular disease and cognitive decline in humans.

Synergistic toxicity of ethanol and MDMA towards primary cultured rat hepatocytes

International Nuclear Information System (INIS)

Pontes, Helena; Sousa, Carla; Silva, Renata; Fernandes, Eduarda; Carmo, Helena; Remiao, Fernando; Carvalho, Felix; Bastos, Maria Lourdes

2008-01-01

Ethanol is frequently consumed along with 3,4-methylenedioxymethamphetamine (MDMA; ecstasy). Since both compounds are hepatotoxic and are metabolized in the liver, an increased deleterious interaction resulting from the concomitant use of these two drugs seems plausible. Another important feature of MDMA-induced toxicity is hyperthermia, an effect known to be potentiated after continuous exposure to ethanol. Considering the potential deleterious interaction, the aim of the present study was to evaluate the hepatotoxic effects of ethanol and MDMA mixtures to primary cultured rat hepatocytes and to elucidate the mechanism(s) underlying this interaction. For this purpose, the toxicity induced by MDMA to primary cultured rat hepatocytes in absence or in presence of ethanol was evaluated, under normothermic (36.5 deg. C) and hyperthermic (40.5 deg. C) conditions. While MDMA and ethanol, by themselves, had discrete effects on the analysed parameters, which were slightly aggravated under hyperthermia, the simultaneous incubation of MDMA and ethanol for 24 h, resulted in high cell death ratios accompanied by a significant disturbance of cellular redox status and decreased energy levels. Evaluation of apoptotic/necrotic features provided clear evidences that the cell death occurs preferentially through a necrotic pathway. All the evaluated parameters were dramatically aggravated when cells were incubated under hyperthermia. In conclusion, co-exposure of hepatocytes to ethanol and MDMA definitely results in a synergism of the hepatotoxic effects, through a disruption of the cellular redox status and enhanced cell death by a necrotic pathway in a temperature-dependent extent

Chronic Supplementation of Paeonol Combined with Danshensu for the Improvement of Vascular Reactivity in the Cerebral Basilar Artery of Diabetic Rats

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Hu, Jing; Li, Ya-Ling; Li, Zi-Lin; Li, Hua; Zhou, Xuan-Xuan; Qiu, Peng-Cheng; Yang, Qian; Wang, Si-Wang

2012-01-01

One of the leading causes of death in the world is cerebrovascular disease. Numerous Chinese traditional medicines, such as Cortex Moutan (root bark of Paeonia suffruticosa Andrew) and Radix Salviae miltiorrhizae (root and rhizome of Salvia miltiorrhiza Bunge), protect against cerebrovascular diseases and exhibit anti-atherosclerotic effects. Traditional medicines have been routinely used for a long time in China. In addition, these two herbs are prescribed together in clinical practice. Therefore, the pharmacodynamic interactions between the active constituents of these two herbs, which are paeonol (Pae) and danshensu (DSS), should be particularly studied. The study of Pae and DSS can provide substantial foundations in understanding their mechanisms and empirical evidence to support clinical practice. This study investigated the effects and possible mechanisms of the pharmacodynamic interaction between Pae and DSS on cerebrovascular malfunctioning in diabetes. Experimental diabetes was induced in rats, which was then treated with Pae, DSS, and Pae + DSS for eight weeks. Afterward, cerebral arteries from all groups were isolated and equilibrated in an organ bath with Krebs buffer and ring tension. Effects of Pae, DSS, and Pae + DSS were observed on vessel relaxation with or without endothelium as well as on the basal tonus of vessels from normal and diabetic rats. Indexes about oxidative stress were also determined. We report that the cerebral arteries from diabetic rats show decreased vascular reactivity to acetylcholine (ACh) which was corrected in Pae, DSS, and Pae + DSS treated groups. Furthermore, phenylephrine (PE)-induced contraction response decreased in the treated groups. Phenylephrine and CaCl2-induced vasoconstrictions are partially inhibited in the three treated groups under Ca2+-free medium. Pre-incubated with tetraethylammonium, a non-selective K+ channel blocker, the antagonized relaxation responses increased in DSS and Pae + DSS treated diabetic

Mitochondrial activity assessed by cytofluorescence after in-vitro-irradiation of primary rat brain cultures

International Nuclear Information System (INIS)

Cervos-Navarro, J.; Hamdorf, G.

1993-01-01

Mitochondria play a key role in cell homeostasis and are the first cell organells affected by ionizing irradiation, as it was proved by previous electron microscopic investigations. In order to observe functional parameters of mitochondria after low-dose irradiation, primary rat brain cultures (prepared from 15-day-old rat fetuses) were irradiated from a 60 Co-source with 0.5 and 1 Gy at the age of 2 or 7 days in vitro (div). Cytofluorescence measurement was made by a Cytofluor trademark2350 using Rhodamine 123. This fluorescent dye is positively charged and accumulates specifically in the mitochondria of living cells without cytotoxic effect. Since its retention depends on the negative membrane potential as well as the proton gradient that exists across the inner mitochondrial membrane, Rhodamine 123 accumulation reflects the status of mitochondrial activity as a whole. After irradiation with 0.5 and 1 Gy on day 2 in culture there was a decrease in Rhodamine uptake in the irradiated cultures during the first week after the irradiation insult which reached minimum values after 3 days. Rhodamine uptake increased during the following period and finally reached the values of the control cultures. In the second experiment with irradiated cultures on day 7 and the same doses of 0.5 and 1 Gy the accumulation of Rhodamine decreased only initially then increased tremendously. After both doses values of Rhodamine-accumulation were higher than the control level. The results demonstrated that irradiation caused a change in mitochondrial activity depending on the time of irradiation. The dramatic increase over the control levels after irradiation on day 7 in vitro is attributed to the fact that at this time synapses have already developed. Deficiency of mitochondrial activity as well as hyperactivity and the consequent change in energy production may lead to changes in neuronal metabolism including an increase in production of free radicals

Culturing of primary rat neurons and glia on ultra-thin parylene-C

International Nuclear Information System (INIS)

Unsworth, C.P.; Delivopoulos, E.; Murray, A.F.

2010-01-01

Full text: In this article, we will describe how we have successfully cultured dissociated embryonic cortical neurons and glia from the postnatal rat hippocampus on extremely thin layers (up to 10 nm) of Parylene-C on a silicon dioxide substrate. Silicon wafers were oxidised, deposited with the biomaterial, Parylene-C, photo-lithographically patterned and plasma etched to produce chips that consisted of lines of Paryl ene-C with varying widths, thickness and lengths. The chips produced were then immersed in Horse Serum and plated with the cells. Ratios of Neurons; Glia; Cell Body were measured on, adjacent to and away from the Parylene-C. Our initial results show how these ratios remained roughly constant for ultra-thin Parylene-C thicknesses of 10 nm as compared to a benchmark thickness of 100 nm (where such cells are known to grow well). Thus, our findings demonstrate that it is possible to culture primary rat neurons and glia to practically cell membrane thicknesses of Parylene-C. Being able to culture cells on such ultra thin levels of Parylene-C will open up the possibility to develop Multi-Electrode Arrays (MEA) that can capacitively couple embedded electrodes through the parylene to the cells on its surface. Thus, providing a neat, insulated passive electrode. Only the ultra-thin thicknesses of Parylene demonstrated here would allow for the rea isation of such a technology. Hence, the outcome of this work, will be of great interest to the Neuroengineering and the Multi-Electrode Array (MEA) community, as an alternative material for the fabric tion of passive electrodes, used in capacitive coupling mode.

Self-Replenishing Vascularized Fouling-Release Surfaces

Energy Technology Data Exchange (ETDEWEB)

Howell, C; Vu, TL; Lin, JJ; Kolle, S; Juthani, N; Watson, E; Weaver, JC; Alvarenga, J; Aizenberg, J

2014-08-13

Inspired by the long-term effectiveness of living antifouling materials, we have developed a method for the self-replenishment of synthetic biofouling-release surfaces. These surfaces are created by either molding or directly embedding 3D vascular systems into polydimethylsiloxane (PDMS) and filling them with a silicone oil to generate a nontoxic oil-infused material. When replenished with silicone oil from an outside source, these materials are capable of self-lubrication and continuous renewal of the interfacial fouling-release layer. Under accelerated lubricant loss conditions, fully infused vascularized samples retained significantly more lubricant than equivalent nonvascularized controls. Tests of lubricant-infused PDMS in static cultures of the infectious bacteria Staphylococcus aureus and Escherichia coli as well as the green microalgae Botryococcus braunii, Chlamydomonas reinhardtii, Dunaliella sauna, and Nannochloropsis oculata showed a significant reduction in biofilm adhesion compared to PDMS and glass controls containing no lubricant. Further experiments on vascularized versus nonvascularized samples that had been subjected to accelerated lubricant evaporation conditions for up to 48 h showed significantly less biofilm adherence on the vascularized surfaces. These results demonstrate the ability of an embedded lubricant-filled vascular network to improve the longevity of fouling-release surfaces.

Warfarin accelerated vascular calcification and worsened cardiac dysfunction in remnant kidney mice

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Ming-Tsun Tsai

2018-04-01

Full Text Available Background: Vascular calcification is highly prevalent in end-stage renal disease (ESRD and is a significant risk factor for future cardiovascular events and death. Warfarin use results in dysfunction of matrix Gla protein, an inhibitor of vascular calcification. However, the effect of warfarin on vascular calcification in patients with ESRD is still not well characterized. Thus we investigated whether arterial calcification can be accelerated by warfarin treatment both in vitro and in vivo using a mouse remnant kidney model. Methods: Human aortic smooth muscle cells (HASMC were cultured in medium supplemented with warfarin and phosphate to investigate the potential role of this drug in osteoblast transdifferentiation. For in vivo study, adult male C57BL/6 mice underwent 5/6 nephrectomy were treated with active vitamin D3 plus warfarin to determine the extent of vascular calcification and parameters of cardiovascular function. Results: We found that the expressions of Runx2 and osteocalcin in HASMC were markedly enhanced in the culture medium containing warfarin and high phosphate concentration. Warfarin induced calcification of cultured HASMC in the presence of high phosphate levels, and this effect is inhibited by vitamin K2. Severe aortic calcification and reduced left ventricular ejection fractions were also noted in 5/6 nephrectomy mice treated with warfarin and active vitamin D3. Conclusion: Warfarin treatment contributes to the accelerated vascular calcification in animal models of advanced chronic kidney disease. Clinicians should therefore be aware of the profound risk of warfarin use on vascular calcification and cardiac dysfunction in patients with ESRD and atrial fibrillation. Keywords: Left ventricular dysfunction, Uremia, Vascular calcification, Warfarin

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

Science.gov (United States)

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

2014-06-01

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

LPS, but not Angiotensin ll, lnduces Direct Pro-lnflammatory Effects in Cultured Mouse Arteries and Human Endothelial and Vascular Smooth Muscle Cells