Nitric oxide is a mediator of tachykinin NK3 receptor-induced relaxation in rat mesenteric artery.
1. The mechanism of vasodilatation induced by tachykinin peptides was studied in isolated mesenteric arteries of rats. 2. Senktide, a selective NK3 agonist, elicited potent endothelium-dependent relaxation of arteries precontracted with phenylephrine (10(-5) M), but an NK1 agonist did not. 3. A non-peptide NK3 antagonist, SR 142801, inhibited senktide-induced relaxation. However, a non-peptide NK1 antagonist, CP-96,345, and a peptide-based NK2 antagonist, L-659,877, had no effect on senktide-induced relaxation. 4. N omega-nitro-L-arginine (L-NOARG), a nitric oxide synthesis inhibitor, markedly attenuated the relaxant response to senktide. 5. These results suggest that the endothelium of rat mesenteric arteries possesses tachykinin NK3 receptors, and that NK3 agonist-induced vasodilatation is mediated by release of nitric oxide (NO) from the endothelium.
Mizuta
A
A
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
Takano
Y
Y
Honda
K
K
Saito
R
R
Matsumoto
T
T
Kamiya
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001011:Aorta / Q000187:drug effects; D004730:Endothelium, Vascular / Q000378:metabolism*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology*; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D018042:Receptors, Neurokinin-3 / Q000819:agonists / Q000502:physiology*; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology; D014664:Vasodilation / Q000502:physiology*
D010446:Peptide Fragments; D018042:Receptors, Neurokinin-3; C054724:senktide; D009569:Nitric Oxide; D013373:Substance P