Renal endothelin in chronic angiotensin II hypertension

2002 ◽  
Vol 283 (1) ◽  
pp. R243-R248 ◽  
Author(s):  
Jennifer M. Sasser ◽  
Jennifer S. Pollock ◽  
David M. Pollock
Keyword(s):  
Sodium Intake ◽  
Renal Tissue ◽  
High Salt ◽  
Ang Ii ◽  
Sprague Dawley ◽  
Outer Medulla ◽  
High Salt Diet ◽  
Salt Diet ◽  
Sprague Dawley Rats ◽  
Saline Vehicle

To determine the influence of chronic ANG II infusion on urinary, plasma, and renal tissue levels of immunoreactive endothelin (ET), ANG II (65 ng/min) or saline vehicle was delivered via osmotic minipump in male Sprague-Dawley rats given either a high-salt diet (10% NaCl) or normal-salt diet (0.8% NaCl). High-salt diet alone caused a slight but not statistically significant increase (7 ± 1%) in mean arterial pressure (MAP). MAP was significantly increased in ANG II-infused rats (41 ± 10%), and the increase in MAP was significantly greater in ANG II rats given a high-salt diet (59 ± 1%) compared with the increase observed in rats given a high-salt diet alone or ANG II infusion and normal-salt diet. After a 2-wk treatment, urinary excretion of immunoreactive ET was significantly increased by ∼50% in ANG II-infused animals and by over 250% in rats on high-salt diet, with or without ANG II infusion. ANG II infusion combined with high-salt diet significantly increased immunoreactive ET content in the cortex and outer medulla, but this effect was not observed in other groups. In contrast, high-salt diet, with or without ANG II infusion, significantly decreased immunoreactive ET content within the inner medulla. These data indicate that chronic elevations in ANG II levels and sodium intake differentially affect ET levels within the kidney and provide further support for the hypothesis that the hypertensive effects of ANG II may be due to interaction with the renal ET system.

scholarly journals Aortic Stiffness and Diastolic Dysfunction in Sprague Dawley Rats Consuming Short-Term Fructose Plus High Salt Diet

2020 ◽  
Vol Volume 13 ◽  
pp. 111-124
Author(s):  
Dragana Komnenov ◽  
Peter E Levanovich ◽  
Natalia Perecki ◽  
Charles S Chung ◽  
Noreen F Rossi
Keyword(s):  
Diastolic Dysfunction ◽  
Aortic Stiffness ◽  
High Salt ◽  
Sprague Dawley ◽  
Short Term ◽  
High Salt Diet ◽  
Salt Diet ◽  
Sprague Dawley Rats

scholarly journals Fructose plus High-Salt Diet in Early Life Results in Salt-Sensitive Cardiovascular Changes in Mature Male Sprague Dawley Rats

Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3129
Author(s):  
Peter E. Levanovich ◽  
Charles S. Chung ◽  
Dragana Komnenov ◽  
Noreen F. Rossi
Keyword(s):  
Phase I ◽  
Left Ventricular ◽  
High Salt ◽  
Male Rats ◽  
Phase Iii ◽  
Lv Function ◽  
Sprague Dawley ◽  
High Salt Diet ◽  
Salt Diet ◽  
Sprague Dawley Rats

Fructose and salt intake remain high, particularly in adolescents and young adults. The present studies were designed to evaluate the impact of high fructose and/or salt during pre- and early adolescence on salt sensitivity, blood pressure, arterial compliance, and left ventricular (LV) function in maturity. Male 5-week-old Sprague Dawley rats were studied over three 3-week phases (Phases I, II, and III). Two reference groups received either 20% glucose + 0.4% NaCl (GCS-GCS) or 20% fructose + 4% NaCl (FHS-FHS) throughout this study. The two test groups ingested fructose + 0.4% NaCl (FCS) or FHS during Phase I, then GCS in Phase II, and were then challenged with 20% glucose + 4% NaCl (GHS) in Phase III: FCS-GHS and FHS-GHS, respectively. Compared with GCS-GCS, systolic and mean pressures were significantly higher at the end of Phase III in all groups fed fructose during Phase I. Aortic pulse wave velocity (PWV) was elevated at the end of Phase I in FHS-GHS and FHS-FHS (vs. GCS-GCS). At the end of Phase III, PWV and renal resistive index were higher in FHS-GHS and FHS-FHS vs. GCS-GCS. Diastolic, but not systolic, LV function was impaired in the FHS-GHS and FHS-FHS but not FCS-FHS rats. Consumption of 20% fructose by male rats during adolescence results in salt-sensitive hypertension in maturity. When ingested with a high-salt diet during this early plastic phase, dietary fructose also predisposes to vascular stiffening and LV diastolic dysfunction in later life.

Relaxation response of abdominal aorta to androgens in orchidectomised Sprague–Dawley rats fed a high-salt diet

2012 ◽  
Vol 90 (12) ◽  
pp. 1647-1651 ◽  
Author(s):  
Ahmed Kolade Oloyo ◽  
Renuka R. Nair ◽  
Chikodi N. Anigbogu ◽  
Olusoga A. Sofola
Keyword(s):  
Abdominal Aorta ◽  
High Salt ◽  
Relaxation Response ◽  
Sprague Dawley ◽  
High Salt Diet ◽  
Salt Diet ◽  
Vasorelaxant Effect ◽  
Sprague Dawley Rats ◽  
The Status ◽  
Gonadal Status

Previous studies have demonstrated the acute relaxant effects of androgens on normal arterial beds, but not on any with underlying or induced pathologies. This study investigated whether the status of the gonads affects the direct actions of androgens on isolated abdominal aorta from male Sprague–Dawley rats fed a high-salt diet. A high-salt diet reduced the relaxation response to exogenous testosterone, but not to dehydroepiandrosterone (DHEA). Orchidectomy reduced the relaxation response to both testosterone and DHEA, while testosterone replacement restored the acute vasorelaxant effect of testosterone and DHEA in both normal and high-salt diet fed rats. Gonadal status appears to be important in the acute vasorelaxant effect of androgens.

scholarly journals Consumption of high sucrose and/or high salt diet alters sperm function in male Sprague–Dawley rats

2016 ◽  
Vol 3 (2) ◽  
pp. 194-201 ◽  
Author(s):  
D.A. Adekunbi ◽  
O.A. Ogunsola ◽  
O.T. Oyelowo ◽  
E.O. Aluko ◽  
A.A. Popoola ◽  
...  
Keyword(s):  
High Salt ◽  
Sperm Function ◽  
Sprague Dawley ◽  
High Salt Diet ◽  
Salt Diet ◽  
Sprague Dawley Rats ◽  
High Sucrose

scholarly journals l-arginine Supplementation Increased Only Endothelium-Dependent Relaxation in Sprague-Dawley Rats Fed a High-Salt Diet by Enhancing Abdominal Aorta Endothelial Nitric Oxide Synthase Gene Expression

2020 ◽  
Vol 14 ◽  
pp. 117954682090284
Author(s):  
Abdullahi Adejare ◽  
Ahmed Oloyo ◽  
Chikodi Anigbogu ◽  
Smith Jaja
Keyword(s):  
Gene Expression ◽  
Vascular Reactivity ◽  
High Salt ◽  
Enos Gene ◽  
Sprague Dawley ◽  
High Salt Diet ◽  
Salt Diet ◽  
Sprague Dawley Rats ◽  
Endothelium Dependent Relaxation ◽  
Arginine Supplementation

Background: Abnormal vascular reactivity and reduced expression of endothelial nitric oxide synthase ( eNOS) gene are hallmark of salt-induced hypertension in rats. Although l-arginine is an established vasodilator, the mechanism by which it modulates vascular reactivity in salt-induced hypertension is not clearly understood. Objectives: This study was designed to investigate the mechanism by which oral l-arginine supplementation modulates vascular reactivity and eNOS gene expression in Sprague-Dawley rats fed a high-salt diet. Methods: Forty-eight weaned male Sprague-Dawley rats of weight range 90 to 110 g were randomly divided into 6 groups of 8 rats per group. Group I was fed normal rat chow ad libitum and served as the Normal Diet group. Group II was fed a diet that contained 8% NaCl. Groups III and IV took normal and high-salt diet, respectively, and then received oral l-arginine supplementation (100 mg/kg/day), while groups V and VI took normal and high-salt diet, respectively, and then were co-administered with both l-arginine and l-nitro-arginine methyl ester (L-NAME; 100 mg/kg/day and 40 mg/kg/day, respectively) orally. At the end of 12-week experimental period, the animals were sacrificed to assess vascular reactivity and gene expression level. Results: Our results show that high-salt diet significantly reduced ( P < .05) endothelium-dependent relaxation response to acetylcholine and qualitatively reduced eNOS gene expression in the abdominal aorta of the rats. However, l-arginine supplementation improved the impaired endothelium-dependent relaxation and nitric oxide level while ameliorating the reduced eNOS gene expressions. Conclusion: This study suggests that oral supplementation of l-arginine enhances endothelial-dependent relaxation in rats fed a high-salt diet by ameliorating eNOS gene expression in the abdominal aorta of the rats.

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