J Ethnopharmacol. 2002 Mar; 79(3): 369-72.

Vasodilator activity of crude methanolic extract of Gentiana kokiana Perr. et Song. (Gentianaceae).

Baragatti B, Calderone V, Testai L, Martinotti E, Chericoni S, Morelli I.

Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, UniversitÃ di Pisa, via Bonanno 6, 56126 Pisa, Italy.

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.