Low-dose lithium combined with captopril prevents stroke and improves survival in salt-loaded, stroke-prone spontaneously hypertensive rats

We have studied during 30 days the effect of a low dose of NG-nitro-L-arginine methyl ester (1 mg ·kg-1 ·day-1 in drinking water) in the presence of D- or L-arginine (1 mg ·kg-1 ·day-1 in drinking water) in comparison with D- or L-arginine alone on blood pressure and renal function in conscious uninephrectomized female spontaneously hypertensive rats. At the end of the study, there was a significant increase in systolic blood pressure in the NG-nitro-L-arginine methyl ester + D-arginine group (307 ± 6 mmHg (1 mmHg = 133.3 Pa), n = 14, p << 0.05) in comparison with NG-nitro-L-arginine methyl ester + L-arginine (281 ± 6 mmHg, n = 14), L-arginine (262 ± 5 mmHg, n = 13), and D-arginine (258 ± 7 mmHg, n = 12) groups. There were no changes in diuresis, proteinuria, or sodium and potassium excretion between differently treated animals during this study. These results suggest that in uninephrectomized female spontaneously hypertensive rats, after 1 month blockade of NO synthesis with a low dose of NG-nitro-L-arginine methyl ester, vasculature is under tonic control by NO and it is not correlated with renal dysfunction.Key words: Key words: NG -nitro-L-arginine methyl ester (L-NAME), kidney, hypertension, spontaneously hypertensive rats, renaldysfunction, uninephrectomy.

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Dexamethasone and Training-Induced Cardiac Remodeling Improve Cardiac Function and Arterial Pressure in Spontaneously Hypertensive Rats

Journal of Cardiovascular Pharmacology and Therapeutics ◽

10.1177/1074248420953271 ◽

2020 ◽

pp. 107424842095327

Author(s):

Francine Duchatsch ◽

Lidieli P. Tardelli ◽

Naiara A. Herrera ◽

Thalles F. R. Ruiz ◽

Carlos A. Vicentini ◽

...

Keyword(s):

Arterial Pressure ◽

Cardiac Remodeling ◽

Spontaneously Hypertensive Rats ◽

Low Dose ◽

Collagen Deposition ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Deposition Area ◽

Systolic And Diastolic Function ◽

And Training

Introduction: Dexamethasone (DEX)-induced hypertension and cardiac remodeling are still unclear, especially in spontaneously hypertensive rats (SHR). On the other side, exercise training is a good strategy to control hypertension. Therefore, this study investigated the effects of DEX treatment and physical training on arterial pressure and cardiac remodeling in SHR. Material and Methods: SHR underwent treadmill training (5 days/week, 1h/session, at 50-60% of maximal capacity, 0% degree, 75 days) and received low-dose of DEX (50µg/kg, s.c.) during the last 15 days. Sedentary Wistar rats (W) were used as control. Echocardiography and artery catheterization were performed for cardiac remodeling and function, arterial pressure and autonomic nervous system analyses. In addition, left ventricle (LV) capillary density, myocyte diameter and collagen deposition area were analyzed using specific histological staining. Results: Low-dose of DEX treatment did not exacerbate arterial pressure of SHR and trained groups had lower values, regardless of DEX. DEX and training decreased relative left ventricle wall thickness (RWT) and determined LV angiogenesis (+19%) and lower collagen deposition area (−22%). In addition, it determined increased left ventricular diastolic diameter. These changes were followed by improvements on systolic and diastolic function, since it was observed increased posterior wall shortening velocity (PWSV) and reduced isovolumetric relaxation time (IVRT). Conclusion: In conclusion, this study is unique to indicate that low-dose of DEX treatment does not exacerbate arterial pressure in SHR and, when associated with training, it improves LV systolic and diastolic function, which may be due to LV angiogenesis and reduction of wall collagen deposition area.

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Propofol Protects Against Hemorrhagic Shock-Induced Organ Damage in Conscious Spontaneously Hypertensive Rats

Biological Research For Nursing ◽

10.1177/1099800409334750 ◽

2009 ◽

Vol 11 (2) ◽

pp. 152-162 ◽

Cited By ~ 7

Author(s):

Chung-Jen Lee ◽

Ru-Ping Lee ◽

Yi-Maun Subeq ◽

Chia-Chi Lee ◽

Tai-Chu Peng ◽

...

Keyword(s):

Hemorrhagic Shock ◽

Spontaneously Hypertensive Rats ◽

Low Dose ◽

Organ Damage ◽

Interleukin 10 ◽

High Dose ◽

Hypertensive Rats ◽

Total Blood ◽

Spontaneously Hypertensive ◽

Blood Withdrawal

Patients with hypertension have higher mortality rates from hemorrhagic shock (HS) than normotensive patients. Several inflammatory mediators such as tumor necrosis factor a (TNF-a) and interleukin 10 (IL-10) can be produced by HS and lead to multiple organ dysfunction and death. We investigated the effects of high dose (10 mg/kg/hr) and low dose (1 mg/kg/hr) propofol treatment after HS in conscious spontaneously hypertensive rats (SHRs). By withdrawing 40% of total blood volume from a femoral arterial catheter (6 ml/100 g body weight [BW]) for more than 30 min, HS was induced. The mean arterial pressure (MAP) and heart rate (HR) were monitored continuously for 24 hr after the start of blood withdrawal. Levels of biochemical parameters, including glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), blood urea nitrogen (BUN), creatinine (Cre), creatine phosphokinase (CPK), and lactic dehydrogenase (LDH) were measured 30 min before and 0, 1, 3, 6, 9, 12, 18, and 24 hr after the 30-min blood withdrawal period. Cytokine levels, including TNF-a and IL-10 in the serum, were measured 1 hr after HS. The kidney, liver, and lung were removed for pathology assessment at 48 hr after HS. HS significantly increased blood GOT, GPT, BUN, LDH, CPK, TNF-a, and IL-10 levels in conscious SHRs. Posttreatment propofol decreased serum TNF-a level, increased serum IL-10 level, attenuated the severity of organ damage, and improved survival rate after HS. This treatment protected SHRs against HS-induced organ damage. Moreover, high-dose propofol had a more protective effect than low-dose propofol against HS in conscious SHRs.

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