L-Arginine Prevents Corticotropin-Induced Increases in Blood Pressure in the Rat

• Published in: Hypertension (Dallas, Tex. 1979) Tex. 1979), 1996-02, Vol.27 (2), p.184-189
• Main Authors: Turner, Steven W, Wen, Cheng, Li, Ming, Whitworth, Judith A
• Format: Article
• Language: English
• Subjects: Adrenal Glands - drug effects; Adrenocorticotropic Hormone - antagonists & inhibitors; Adrenocorticotropic Hormone - pharmacology; Analysis of Variance; Animals; Antihypertensive agents; Arginine - pharmacology; Biological and medical sciences; Blood Pressure - drug effects; Body Weight - drug effects; Cardiovascular system; Heart - drug effects; Hypertension - chemically induced; Hypertension - prevention & control; Kidney - drug effects; Male; Medical sciences; Organ Size - drug effects; Pharmacology. Drug treatments; Potassium - blood; Rats; Rats, Sprague-Dawley; Reference Values; Sodium - blood; Time Factors
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/01.hyp.27.2.184

In this study we examined whether L-arginine treatment could prevent corticotropin (ACTH)-induced increases in blood pressure in the Sprague-Dawley rat. Sixty rats were randomly divided into six groups (n = 10)sham injection, ACTH injection (0.5 mg/kg per day in divided doses), L-arginine (0.6%) in food plus sham injection, L-arginine plus ACTH treatment, D-arginine (0.6%) in food plus sham injection, and D-arginine plus ACTH. Systolic pressure, water intake, urine volume, body weight, plasma and urinary electrolytes, and serum corticosterone concentrations were measured. ACTH increased systolic pressure (from 127 plus/minus 2 to 165 plus/minus 6 mm Hg, P < .001), water intake, and urine volume and decreased body weight. L-Arginine reduced ACTH-induced blood pressure rises (130 plus/minus 3 mm Hg, P < .001) but had no effect on blood pressure in sham-treated rats. D-Arginine did not affect blood pressure in sham-treated rats, and systolic pressure in D-arginine + ACTH-treated rats was similar to that of ACTH-treated rats. L-Arginine decreased serum corticosterone concentrations in sham-treated rats (424 plus/minus 43 versus 238 plus/minus 25 ng/mL, P < .01), but D-arginine had no effect. However, both drugs decreased serum corticosterone concentrations in ACTH-treated rats (1071 plus/minus 117 versus 739 plus/minus 95 and 695 plus/minus 72 ng/mL for L- and D-arginine, respectively; both P < .05). As L-arginine but not D-arginine prevented ACTH-induced increases in blood pressure in Sprague-Dawley rats and both L- and D-arginine reduced serum corticosterone concentrations in ACTH-treated rats, the effects of L-arginine in preventing ACTH-induced hypertension were not simply a consequence of decreased corticosterone secretion. (Hypertension. 1996;27:184-189.)