Long-term L-arginine administration normalized pressure-natriuretic responses and lowered mean arterial pressure (127 vs 158 mm Hg) in salt-sensitive rats on a high-sodium diet.
Does L-arginine administration normalize pressure natriuresis in hypertensive Dahl salt-sensitive rats?
Long-term L-arginine administration normalizes pressure-natriuretic responses in salt-sensitive rats, an effect that is specific to the salt-sensitive strain and not due to the prevention of renal damage.
p-value: p=<.05
A blunted pressure-natriuretic response characterizes hypertension in the Dahl salt-sensitive rat. Long-term L-arginine administration prevents hypertension in these animals. To determine if long-term L-arginine corrects the pressure-natriuretic response, we gave salt-sensitive rats on an 8% sodium diet L-arginine or vehicle daily for 3 weeks. Identically treated salt-resistant rats served as controls. After 3 weeks, acute pressure-natriuresis curves were determined. To control for hypertension-induced renal damage, we also examined pressure natriuresis in salt-sensitive rats after short-term L-arginine. Baseline mean arterial pressure was 158 +/- 3 mm Hg in vehicle-treated salt-sensitive rats and 127 +/- 3 mm Hg in chronically L-arginine-treated salt-sensitive rats. During alterations in perfusion pressure, renal blood flow was autoregulated in all groups. Glomerular filtration rate was autoregulated in salt-resistant rats and L-arginine-treated salt-sensitive rats but fell with decreasing pressure in vehicle-treated salt-sensitive rats. Sodium excretion was greater (P < .05) in L-arginine-treated than in vehicle-treated salt-sensitive rats and did not differ from salt-resistant rats at 100, 125, and 158 mm Hg. The slope of the pressure-natriuresis relation was greater (P < .05) in chronically L-arginine-treated than in vehicle-treated salt-sensitive rats. L-Arginine had no effect on natriuresis in salt-resistant rats. Thus, long-term L-arginine administration normalizes pressure-natriuretic responses in salt-sensitive rats. The effect is not due to the prevention of renal damage and is specific to the salt-sensitive strain.(ABSTRACT TRUNCATED AT 250 WORDS)
Patel et al. (Wed,) conducted a other in Hypertension. L-arginine vs. vehicle was evaluated on Pressure-natriuretic response (p=<.05). Long-term L-arginine administration normalized pressure-natriuretic responses and lowered mean arterial pressure (127 vs 158 mm Hg) in salt-sensitive rats on a high-sodium diet.