Ginkgo biloba extract-induced relaxation of rat aorta is associated with increase in endothelial intracellular calcium level.

  title={Ginkgo biloba extract-induced relaxation of rat aorta is associated with increase in endothelial intracellular calcium level.},
  author={Yōko Kubota and Naoko Tanaka and Keizo Umegaki and H Takenaka and Hideya Mizuno and K I Nakamura and Kazumasa Shinozuka and Masaru Kunitomo},
  journal={Life sciences},
  volume={69 20},
Ginkgo biloba extract (GBE) has been used clinically for improving peripheral vascular diseases in France and Germany. In the present study, to clarify the pharmacological properties of vasodilation produced by GBE, we examined the effect of GBE and quercetin, one of the ingredients in GBE, on the thoracic aorta isolated from Wistar rats. GBE produced a dose-dependent relaxation in the aortic ring precontracted with noradrenaline, and the relaxation was abolished by L-N(G)-nitro arginine methyl… Expand
Effects of Ginkgo biloba extract feeding on salt-induced hypertensive Dahl rats.
It is demonstrated that GBE reduced salt-related elevation of blood pressure and restored the impaired acetylcholine-induced vasodilation in aortic segments. Expand
Mechanisms for the vasodilations induced by Ginkgo biloba extract and its main constituent, bilobalide, in rat aorta.
The results indicate that the relaxation induced by GBE would be due to the inhibition of Ca( 2+) influx through the Ca(2+) channel and the activation of NO release, and might be in partdue to the inhibitions ofCa(2+)-activated K(+) current and PGI(2) release, in the endothelium and aortic vascular muscles. Expand
Effects of quercetin and rutin on vascular preparations
The mechanical and electrophysiological properties of quercetin and its rutoside, rutin, are investigated in an attempt to clarify how Ca2+ channel activation might be related to the myorelaxing activity. Expand
Effects of ginkgo biloba extract on cation currents in rat ventricular myocytes.
Results suggested that GBE is a potent non-selective cation channel modulator in cardiaomyocytes, and other constituents (rather than GB A, GB B and GB BA) might be responsible for the observed inhibitory effects of GBE on cation channels. Expand
Dose-dependent Differential Mechanism of Quercetin-induced Vasodilatations in Isolated Perfused Rat Mesenteric Vascular Bed
It is suggested that quercetin induces endothelium-dependent vasodilatations at lower concentrations by increasing the bioactivity of sustained nitric oxide release evoked by perfusion pressure, however, the vasodILatations induced by high concentrations of quercETin are endothelia-independent. Expand
Ginkgo biloba extract EGb® 761 increases endothelial nitric oxide production in vitro and in vivo
Phosphorylation of eNOS at a site typical for Akt was acutely enhanced by treatment with EGb® 761, as was Akt phosphorylation at Ser 478, which represents a putative molecular basis for the protective cardiovascular properties of EGb®, 761. Expand
Electropharmacological actions of Ginkgo biloba extract on vascular smooth and heart muscles.
The results indicate that GBE and the constituents produce effective electropharmacological actions in the cardiomyocytes and cause vasodilation, mainly due to the inhibitions ofCa2+ influx through the Ca2+ channel and the activation of NO release in the endothelium and aortic vascular muscles. Expand
Effects of Ginkgo biloba extract on blood pressure and vascular endothelial response by acetylcholine in spontaneously hypertensive rats
The results suggested that Ginkgo enhanced endothelium‐dependent vasodilation and elevation of the endothelial intracellular Ca2+ level in SHR, resulting in hypotension, and was associated with restoration of impaired dilatory function induced by acetylcholine in endothelial cells. Expand
Role of gap junction involved with endothelium-derived hyperpolarizing factor for the quercetin-induced vasodilatation in rat mesenteric artery.
The results indicate that quercetin dilates the mesenteric artery via endothelium-dependent mechanisms, and the dilatation is mainly mediated by gap junctions closely involved with endothelia-derived hyperpolarizing factor (EDHF). Expand
Study on mechanism of vasorelaxatory effect of Vitis vinifera leaf extract in rat aorta
The results suggest that Vitis vinifera leaf hydroalcoholic extract induces relaxation in rat aorta possibly by opening the Ca 2+ -operated K + channels but, not ATP- sensitive K + channel and extracellular calcium was essential for inducing vasorelaxation by extract. Expand