Renal vasoconstriction is modulated by nitric oxide.
1. The effect of the nitric oxide synthesis inhibitor, NG-nitro-L-arginine (NOLA), has been examined on vascular reactivity in the rat isolated perfused kidney. 2. NOLA (10 mumol/L) had no effect on basal perfusion pressure, but significantly enhanced the vasoconstrictor responses to sympathetic nerve stimulation (1-16 Hz, 10 s) and noradrenaline (10-300 pmol). The enhancements were greater with the lower frequencies of stimulation and lower doses of noradrenaline. 3. The enhancing effect of 10 mumol/L NOLA on vasoconstrictor responses to nerve stimulation was partially prevented by 100 mumol/L L-arginine while 100 mumol/L D-arginine had no effect. 4. The results suggest that nitric oxide attenuates vasoconstrictor responses in the rat kidney, and provide evidence that nitric oxide has a physiological role in the modulation of vascular reactivity.
Reid
J J
JJ
Department of Pharmacology, University of Melbourne, Victoria, Australia.
Rand
M J
MJ
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004558:Electric Stimulation; D005260:Female; D007668:Kidney / Q000098:blood supply*; D008297:Male; D009569:Nitric Oxide / Q000494:pharmacology*; D019335:Nitroarginine; D009638:Norepinephrine / Q000494:pharmacology; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D013564:Sympathetic Nervous System / Q000502:physiology; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology*
D019335:Nitroarginine; D009569:Nitric Oxide; D001120:Arginine; D009638:Norepinephrine