1. Inhibition of Intracellular Calcium Elevation and Blunting of Vasopressor Response due to Serotonin by Ginkgolide B
- Author
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Yu Wang, Ying-Qun Yu, and Jian-Guo Xu
- Subjects
Male ,Serotonin ,Vascular smooth muscle ,Pharmaceutical Science ,chemistry.chemical_element ,Aorta, Thoracic ,Biology ,Calcium ,Pharmacology ,Calcium in biology ,Potassium Chloride ,Analytical Chemistry ,Rats, Sprague-Dawley ,Lactones ,Norepinephrine ,Drug Discovery ,medicine ,Animals ,Vasoconstrictor Agents ,Ginkgoales ,Cells, Cultured ,Dose-Response Relationship, Drug ,Molecular Structure ,Plant Extracts ,Organic Chemistry ,Ginkgo biloba ,Free Radical Scavengers ,Calcium Channel Blockers ,biology.organism_classification ,Mesenteric Arteries ,Rats ,Ginkgoaceae ,Ginkgolides ,Verapamil ,Complementary and alternative medicine ,chemistry ,Mechanism of action ,Biochemistry ,Molecular Medicine ,Cattle ,Diterpenes ,medicine.symptom ,Vasoconstriction - Abstract
The vascular effects of each individual composition in the extract of Ginkgo biloba have not been clarified. In this work, we have investigated whether ginkgolide B (GKB), a terpene lactone component from Ginkgo biloba, modulates intracellular calcium ([Ca (2+)] i) of vascular smooth muscle cells (smc) and how it influences the vasopressor response in vitro caused by serotonin (5-HT). GKB (3.2 - 9.6 microM) selectively decreased serotonin-induced [Ca (2+)] i elevations in cultured smc from bovine aorta in dose-dependent manner, while it had no effects on both resting [Ca (2+)] i and potassium-elicited [Ca (2+)] i elevations. On the other hand, GKB in a concentration of 3.2 - 9.6 microM moderately decreased the maximal pressor efficacy of serotonin by 14 - 45 % in rat mesenteric vascular beds, and the EC50 remained unchanged. The comparison study also showed GKB had no effects on noradrenaline-elicited pressor reactions. These results implicate that GKB may selectively inhibit serotonin-mediated [Ca (2+)] i mobilization in vascular smc and non-competitively alleviate the vasopressor effect of serotonin in vitro.
- Published
- 2002