Effects of Chronic Eta-Receptor Blockade in Stroke-Prone Spontaneously Hypertensive Rats.

Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 699-700
Author(s):  
Christine Elise Barandier ◽  
Zhihong Yang ◽  
Thomas Felix Luscher

P38 It has been reported that some ET-receptor blockers prevent cerebral injury in stroke-prone spontaneously hypertensive rats (SPSHR), whereas chronic inhibition of nitric oxide synthase (NOS) precipitates stroke. We investigated the protective effects of chronic treatment with BSF208075, a selective ETA-receptor blocker in SPSHR treated with the NOS inhibitor, L-NAME, or untreated. 4 groups of male SPSHR, 10 week old, were studied: a control group and 3 groups treated with BSF208075 (30 mg/kg/day), L-NAME (10 mg/kg/day) or BSF208075+L-NAME (30 and 10 mg/kg/day, respectively). Systolic blood pressure, body weight and survival were recorded. In the control group, severe hypertension (292.3±1.0mmHg; p<0.01 vs baseline) developed within 4 weeks. In contrast, in the BSF208075-treated group, the development of hypertension (265.2±3.8mmHg; p<0.01 vs control) was limited and blood pressure started to decrease after 4 weeks of treatment. In both of these groups, the increase in body weight was normal and similar, and 90% of the animals were still alive after 50 days of treatment. In the L-NAME-treated group, the blood pressure immediately and drastically increased, the body weight was reduced by 50% within 6 weeks of treatment. 50% of mortality was observed after 22 days of treatment, and all rats died within 36 days. The mean survival was 25.9±2.4 days. In L-NAME+BSF208075-treated group, BSF208075, although it did not prevent the development of hypertension, it reduced the loss of body weight and increased mean survival to 36.7±1.4 days (p<0.01 vs L-NAME-treated group). In this group, 50% of mortality was observed after 37 days of treatment, and all rats died within 41 days. These results show that BSF208075 delays the development of hypertension in SPSHR, and increases survival of L-NAME-treated SPSHR, independent of hypertension.

1985 ◽  
Vol 69 (5) ◽  
pp. 511-515 ◽  
Author(s):  
P. J. O. Manhem ◽  
S. A. Clark ◽  
W. B. Brown ◽  
G. D. Murray ◽  
J. I. S. Robertson

1. Chlorothiazide (100 mg/kg body weight) was given by gavage daily to spontaneously hypertensive rats for 4 weeks. Another group of spontaneously hypertensive rats was given only tap water and served as control. 2. Measurements of total exchangeable sodium, blood pressure and weight were performed for 2 weeks before and for 4 weeks during treatment. 3. Before treatment, exchangeable sodium, blood pressure and weight were similar in the two groups of rats. 4. Chlorothiazide significantly attenuated the blood pressure increase in spontaneously hypertensive rats, the effect being most marked during the first 2 1/2 weeks of treatment and less thereafter. 5. Rats in the chlorothiazide-treated group gained weight more slowly than did those of the control group. 6. Exchangeable sodium, expressed as mmol/kg body weight, did not differ significantly between the two groups at any stage. 7. When exchangeable sodium was expressed as mmol/rat, there was a more gradual rise in the chlorothiazide-treated animals, in accordance with their slower gain in weight. 8. There was no temporal association between the antihypertensive effect of chlorothiazide and changes in exchangeable sodium. 9. Thus whereas chlorothiazide treatment of spontaneously hypertensive rats slows the increase of both weight and exchangeable sodium, other mechanisms are apparently responsible for the antihypertensive action of the drug.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Noemi López-Carreras ◽  
Sandra Fernández-Vallinas ◽  
Marta Miguel ◽  
Amaya Aleixandre

The effect of long-term intake of different doses (20, 40, and 60 mg/kg/day) of aFraxinus excelsiorL. seed extract (FESE) on spontaneously hypertensive rats (SHR) was evaluated. Water was used as control and captopril (50 mg/kg/day) was used as positive control. Systolic blood pressure, body weight, and food and liquid intake were registered weekly in SHR. The antioxidant and vascular relaxing properties of FESE were also studied in these animals. The development of hypertension was attenuated in the groups treated with captopril or FESE. The antihypertensive effect was more accentuated in the captopril group than in the FESE groups, and it was paradoxically more accentuated in the groups treated with 20 mg/kg/day or 40 mg/kg/day of FESE than in the group treated with the highest dose of this extract. Body weight gain and food intake increased in the FESE groups. After removing the corresponding antihypertensive treatment, the arterial blood pressure and the body weight of the FESE treated animals returned to control values. In addition, FESE increased plasma antioxidant capacity and decreased plasma and liver malondialdehyde levels. Moreover, acetylcholine relaxation improved in the aorta rings from the FESE treated rats.


2014 ◽  
Vol 60 (01) ◽  
pp. 53-59
Author(s):  
Kalina Gjorgjievska ◽  
Dimce Zafirov ◽  
Maja Jurhar Pavlova ◽  
Svetlana Cekovska

The goal of this study was to compare the effects of valsartan and amlodipin on the systolic blood pressure and parameters specific to the renal function in salt loaded spontaneously hypertensive rats (SHR). 32 male SHR were used at age of 20 weeks and body weight ranging between 265-300 g. From 8 weeks of age tab water was replaced with a solution of NaCl (1%) given ad libitum. Rats were divided into 2 groups: valsartan treated group SHRVAL (n=16) in which valsartan was given at a dose of 10 mg/kg b. w. and amlodipine treated group SHRAMLO (n=16) in which amlodipine was given at a dose of 5 mg/kg b. w. For a period of 12 weeks we have evaluated the effect of the investigated drugs on systolic blood pressure, body weight and renal function tests. In salt loaded rats amlodipine was more effective in reducing the systolic blood pressure in contrast to valsartan who had more pronounced effect on renal parameters most evident in proteinuria. Since both treatment groups have different mechanism of action a combination therapy may be beneficial in improving renal function in SHR rats.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Kenjiro Tatematsu ◽  
Daisuke Miyazawa ◽  
Yoshiaki Saito ◽  
Harumi Okuyama ◽  
Naoki Ohara

Abstract Background Canola oil (Can) and several vegetable oils shorten the lifespan of stroke-prone spontaneously hypertensive rats (SHRSP). Although similar lifespan shortening has been reported for partially hydrogenated Can, the efficacy of fully hydrogenated oils on the lifespan remains unknown. The present study aimed to investigate the lifespan of SHRSP fed diets containing 10 % (w/w) of fully hydrogenated Can (FHCO) or other oils. Methods Survival test: Upon weaning, male SHRSP were fed a basal diet for rodents mixed with one of the test oils —i.e., FHCO, Can, lard (Lrd), and palm oil (Plm) throughout the experiment. The animals could freely access the diet and drinking water (water containing 1 % NaCl), and their body weight, food intake, and lifespan were recorded. Biochemical analysis test: Male SHRSP were fed a test diet with either FHCO, Can, or soybean oil (Soy) under the same condition, except to emphasize effects of fat, that no NaCl loading was applied. Soy was used as a fat source in the basal diet and was set the control group. Blood pressures was checked every 2 weeks, and serum fat levels and histological analyses of the brain and kidney were examined after 7 or 12 weeks of feeding. Results During the survival study period, the food consumption of FHCO-fed rats significantly increased (15–20 % w/w) compared with that of rats fed any other oil. However, the body weight gain in the FHCO group was significantly less (10–12 %) than that in the control group at 9–11 weeks old. The FHCO (> 180 days) intervention had the greatest effect on lifespan, followed by the Lrd (115 ± 6 days), Plm (101 ± 2 days), and Can (94 ± 3 days) diets. FHCO remarkably decreased the serum cholesterol level compared with Can and the systolic blood pressure from 12 to 16 weeks of age. In addition, while some rats in the Can group exhibited brain hemorrhaging and renal dysfunction at 16 weeks old, no symptoms were observed in the FHCO group. Conclusion This current study suggests that complete hydrogenation decreases the toxicity of Can and even prolongs the lifespan in SHRSP.


2005 ◽  
Vol 108 (4) ◽  
pp. 349-355 ◽  
Author(s):  
Daniele G. BEZERRA ◽  
Carlos A. MANDARIM-de-LACERDA

The aim of the present study was to investigate the possibility of different effects of the hydrophobic statin simvastatin and the hydrophilic statin pravastatin on the remodelling process in the overloaded left ventricle and renal cortex of SHRs (spontaneously hypertensive rats). Fifteen SHRs were treated for 40 days with simvastatin, pravastatin or placebo (water) via orogastric administration. Left ventricle and renal cortex were examined by light microscopy and stereology. LV (left ventricular) cardiomyocyte nuclei (N[cmn]) and glomeruli (N[gl]) numbers were estimated by the dissector method. BP (blood pressure) and serum triacylglycerols (triglycerides) were lower in the statin-treated groups than in the untreated control group. The volume density of the interstitial connective tissue was smaller and length density of the intramyocardial arteries, as well as the arteries/cardiomyocyte ratio, was greater in the statin-treated groups than in the control group. No difference was observed between the two statin-treated groups. The cross-sectional cardiomyocyte area was significantly smaller in the simvastatin-treated group than in the control or pravastatin-treated groups, and it was smaller in the pravastatin-treated group than in the control group. N[cmn] and N[gl] were greater in the two statin-treated groups than in the control group, but no significant difference was observed between the two statin-treated groups. In conclusion, administration of the statins simvastatin and pravastatin to SHRs effectively prevented the elevation in BP and serum triaclyglycerols, and also attenuated adverse cardiac and kidney remodelling by preventing LV hypertrophy, enhancing myocardial vascularization with the decrease in interstitial fibrosis and attenuating cardiomyocyte and glomerular loss.


2005 ◽  
Vol 33 (03) ◽  
pp. 449-457 ◽  
Author(s):  
Hirozo Goto ◽  
Yohei Sasaki ◽  
Hirotoshi Fushimi ◽  
Naotoshi Shibahara ◽  
Yutaka Shimada ◽  
...  

Curcuma herbs have a vasodilator effect. The effects of C. longa, which induces only endothelium-independent vasodilatation, and C. zedoaria, which induces both endothelium-dependent and -independent vasodilatation, were studied on vasomotion and hemorheology in spontaneously hypertensive rats. Spontaneously hypertensive eight-week-old male rats were assigned to five groups. For 12 weeks, the control group received standard chow. The 3%CL (C. longa) group received standard chow containing 3% (wt/wt) C. longa. The 1%CZ and 3%CZ (C. zedoaria) groups received standard chow containing 1% and 3% (wt/wt) C. zedoaria, respectively. The captoril group received standard chow and 100 mg/kg/day of captoril in drinking water. Blood pressure, vasomotion, hemorheology, etc. were examined. Systolic blood pressure of the 3%CZ and captoril groups decreased significantly as compared to the control group. Acetylcholine-induced endothelium-dependent relaxations of the 3%CZ and captoril groups were increased to a greater degree, significantly, than the control group. When testing xanthine oxidase-induced contraction, the 3%CZ group was significantly decreased as compared to the control group. Low shear stress of whole blood viscosity showed the 3%CL and 3%CZ groups to be decreased significantly compared to the control group. Thus, Curcuma herbs have hypotensive and protective effect on the endothelium in spontaneously hypertensive rats. Especially, C. zedoaria is more effective than C.longa, and its mechanism is thought to be related to a radical scavenging effect and improvement of hemorheology.


Author(s):  
Nadeem Yaqoob

Introduction: NSAIDs are known to cause salt and water retention leading to hypertension and renal impairment. Aloe vera gel has been used in medicinal preparations for decades. Limited data is available regarding effect of Aloe vera on renal function. There is a need to search this aspect of Aloe vera, to use it judiciously. Aims & Objectives: To estimate and compare the effects of Aloe vera and diclofenac on systolic blood pressure and renal functions of hypertensive rats. Place and duration of study: This study was conducted at Post Graduate Medical Institute Lahore, Sargodha Medical College, Sargodha and Department of Pharmacy, University of Sargodha for the period of three months. Material & Methods: Male Sprague Dawley rats (n=24) were divided into four groups; Group A (Normal control), Group B (Hypertensive control), Group C (Aloe vera treated) and Group D (Diclofenac treated). Hypertension was induced in groups B, C and D by 20% sucrose diet in 8 weeks. After induction of hypertension, distilled water, dried Aloe vera gel 400 mg/kg and diclofenac 12 mg/kg were given orally to group B, C and D respectively for 2 weeks as a single morning dose. Body weight and systolic blood pressure were measured weekly, while serum creatinine, creatinine clearance and urinary proteins were estimated and compared at 0, 8 and 10 weeks. Data was analyzed using SPSS 23 and p value of ?0.05 was considered significant. Results: Diclofenac decreased body weight of rats non-significantly and increased systolic blood pressure significantly (p< 0.03) whereas Aloe vera increased body weight significantly (p<0.012) and had no significant effect on systolic blood pressure. Diclofenac treated group showed deterioration of renal function as compared to Aloe vera treated group numerically. Conclusion: Aloe vera may be safer anti-inflammatory agent than diclofenac for treatment of chronic inflammatory conditions if the patient also has hypertension or renal disease.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Lei Zhang ◽  
Jie Yu ◽  
Yingying Liu ◽  
Weixing Guo ◽  
Yunlun Li

Objectives. Yishenjiangyafang is a traditional Chinese medicine used to clinically treat hypertension. This study aimed to explore the effect of yishenjiangyafang on plasma metabolomics in senile spontaneously hypertensive rats (SHRs). Methods. Twelve 50-week-old SHR (6 males and 6 females) were randomly divided into two groups: a treatment group, in which rats were intragastrically administered with yishenjiangyafang (10.08 g kg−1·d−1), and a model group, in which all SHRs were administered the same volume of saline. Six age- and gender-matched Wistar–Kyoto (WKY) rats were used as the control group. Treatment was given for 6 days per week and lasted for 8 weeks. Systolic and diastolic blood pressures of the rats were measured with the noninvasive tail artery pressure measurement system. An ultraperformance liquid chromatography quadruple electrostatic field orbit (UPLC-Q-Exactive) was used to determine metabolite changes in the plasma of SHR rats before and after yishenjiangyafang treatment in the treatment group as well as in the model and control groups. Results. After yishenjiangyafang treatment, SHRs had significant lower blood pressure. Using UPLC-Q-Exactive, we identified 26 metabolic targets of yishenjiangyafang in aged SHRs and revealed that yishenjiangyafang targeted four major metabolic pathways, linoleic acid metabolism, glycerophospholipid metabolism, arginine and proline metabolism, and steroid hormone biosynthesis. Conclusion. Yishenjiangyafang decreases the blood pressure of SHRs at least in part through targeting of four major metabolic pathways. Our study illustrates mechanisms underlying the clinical application of yishenjiangyafang in the treatment of hypertensive patients.


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