title: Vasodilator activity of crude methanolic extract of Gentiana kokiana Perr. et Song. (Gentianaceae).
abstract: Gentiana kokiana Perr. et Song. is a plant employed in the traditional medicine of Tuscany (Italy) as antihypertensive remedy. The aim of this work was to evaluate a possible vascular action of the plant and to investigate its mechanism of action. The methanolic extract of roots showed an endothelium-independent vasodilator activity in aortic rings pre-contracted by norepinephrine (NE) 3 microM and a marked depression of the contracturant responses induced by KCl and caffeine, and by NE, both in Tyrode solution and Ca2+-free Tyrode solution. An action on the Ca2+-extracellular influx was discarded, while release or uptake mechanisms of the sarcoplasmic reticulum were hypothesized. However, the incapacity of cyclopiazonic acid (20 microM), a blocker of Ca2+/ATPase of the sarcoplasmic reticulum, to reduce the vasodilator action of the extract allowed to exclude the involvement of such a mechanism. A possible involvement of the ryanodine-sensitive Ca2+ channels is suggested.
authors.affiliation: Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università di Pisa, via Bonanno 6, 56126 Pisa, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Baragatti
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Calderone
authors.forename: Lara
authors.initials: L
authors.lastname: Testai
authors.forename: Enrica
authors.initials: E
authors.lastname: Martinotti
authors.forename: Silvio
authors.initials: S
authors.lastname: Chericoni
authors.forename: Ivano
authors.initials: I
authors.lastname: Morelli
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D029965:Gentianaceae; D008519:Medicine, Traditional; D000432:Methanol / Q000494:pharmacology*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012997:Solvents / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D012997:Solvents; D014665:Vasodilator Agents; D000432:Methanol