Basal and stimulated nitric oxide in control of kidney function in the aging rat

摘要: To investigate the activity of nitric oxide (NO) in control renal hemodynamics during aging, studies were conducted on conscious Sprague-Dawley rats aged 3-5 mo (young, Y) and 18-22 (old, O). Blood pressure (BP) vascular resistance (RVR) higher O vs. Y control, acute systemic NO synthesis inhibition (NOSI) increased BP RVR, with an enhanced vasoconstrictor response O. Infusion substrate L-arginine produced similar, selective vasodilation both groups. The endothelium-dependent vasodilator acetylcholine caused similar falls whereas sodium nitroprusside exaggerated depressor without RVR either age group. Urinary excretion stable oxidation products (NOx) decreased age, suggesting a decline overall somatic production. In conclusion, basal tonically has more pronounced role maintenance perfusion L-arginine- agonist-stimulated is not impaired age. production from some source may be reduced as indicated by 24-h NOX excretion, although similarity pressor to NOSI suggests that total peripheral maintained.