Comparison of actions of endothelium-derived nitric oxide and sodium nitroprusside on mechanical responses evoked in aorta and mesenteric artery of the rabbit.
1. The effects were investigated of endothelium-derived nitric oxide (EDNO; EDRF) and sodium nitroprusside (SNP) on the contraction evoked by noradrenaline (NA) or perivascular nerve stimulation in the presence (+E) or absence (-E) of endothelial cells in the rabbit mesenteric artery and aorta. 2. Acetylcholine (ACh) was more potent in relaxing (+)-tissues of the aorta than those of the mesenteric artery. These relaxing effects of ACh were inhibited under pretreatment with NG-nitro-L-arginine (L-NNA). 3. SNP relaxed the contraction evoked by NA or electric field stimulation in the aorta more than in the mesenteric artery in the presence or absence of endothelium. L-NNA (> 15 microM) consistently enhanced the amplitude of contraction evoked by either NA or electric field stimulation more strongly in (+E)-tissues from the mesenteric artery than in these from the aorta. 4. L-NNA accelerated the relaxing actions of SNP on contractions evoked by NA in (+E)-tissues prepared from the mesenteric artery though this action was less marked in the aorta. 5. Spontaneous release of EDNO is more potent in inhibiting contraction evoked in the mesenteric artery than in the aorta, whereas derived NO and exogenously applied NO are more potent in inhibiting contraction evoked in the aorta than in the mesenteric artery.
Li
J Y
JY
Department of Pharmacology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Kuriyama
H
H
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004558:Electric Stimulation; D004730:Endothelium, Vascular / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*; D019335:Nitroarginine; D009599:Nitroprusside / Q000494:pharmacology*; D011817:Rabbits; D014661:Vasoconstriction / Q000187:drug effects*
D009599:Nitroprusside; D019335:Nitroarginine; D009569:Nitric Oxide; D001120:Arginine; D000109:Acetylcholine