title: Biphasic relaxation caused by electrical field stimulation of the mesenteric arteries of rats.
abstract: Electrical field stimulation (EFS) caused biphasic relaxation, first transient and then sustained, of rat mesenteric arteries precontracted by prostaglandin (PG) F2alpha. The transient relaxation was reduced about 45%, and the sustained relaxation was not observed after endothelium denudation of the arteries. N(omega)-Nitro-L-arginine (L-NOARG) inhibited the biphasic relaxation induced by EFS. At 1 - 100 microM, L-NOARG inhibited the transient relaxation more than the sustained relaxation. Methylene blue inhibited the biphasic relaxation and at 100 microM, L-NOARG abolished the transient relaxation. These results suggest that the transient relaxation mainly involves nitric oxide (NO), whereas the sustained relaxation involves both NO and some other factor(s).
authors.affiliation: Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Handa
authors.forename: S
authors.initials: S
authors.lastname: Tanaka
authors.forename: A
authors.initials: A
authors.lastname: Fukumitsu
authors.forename: K
authors.initials: K
authors.lastname: Honda
authors.forename: Y
authors.initials: Y
authors.lastname: Takano
authors.forename: H
authors.initials: H
authors.lastname: Kamiya
mesh_terms: D000818:Animals; D015237:Dinoprost / Q000494:pharmacology; D004558:Electric Stimulation; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000502:physiology*; D009126:Muscle Relaxation; D019335:Nitroarginine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D019335:Nitroarginine; D015237:Dinoprost