Vasodilator activity of crude methanolic extract of Gentiana kokiana Perr. et Song. (Gentianaceae).
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.
Baragatti
Barbara
B
Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università di Pisa, via Bonanno 6, 56126 Pisa, Italy.
Calderone
Vincenzo
V
Testai
Lara
L
Martinotti
Enrica
E
Chericoni
Silvio
S
Morelli
Ivano
I
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*
D010936:Plant Extracts; D012997:Solvents; D014665:Vasodilator Agents; D000432:Methanol