title: Hypoxia-induced von Willebrand factor release is blocked by verapamil.
abstract: Hypoxia-induced stimulation of the rate of von Willebrand factor (vWF) release from human umbilical vein endothelial cells in culture, and the influence of the calcium antagonist verapamil, was studied using a system in which a pO2 of 20 mm Hg was achieved over 60 min. The mean +/- SEM rate of vWF release over 60 min in normoxia was 0.42 +/- 0.07% pooled plasma standard. The addition of verapamil did not alter the basal rate of vWF release, but after 60 min of hypoxia, the rate was increased to 0.71 +/- 0.03% plasma standard (p < 0.01). Verapamil at a concentration of 0.1 microgram/ml of media had no influence on the stimulated rate of release (0.78 +/- 0.07%), but increasing concentrations of verapamil up to a maximum of 1 microgram/ml attenuated the hypoxia induced stimulation (0.48 +/- 0.07%; p = 0.04 vs. hypoxic control). Thus, verapamil at this concentration completely blocked the hypoxia-induced stimulation.
authors: Department of Nephrology, Royal London Hospital, UK.
authors: M E
authors: ME
authors: Wilkie
authors: C R
authors: CR
authors: Stevens
authors: J
authors: J
authors: Cunningham
authors: D
authors: D
authors: Blake
mesh_terms: D000001:Calcimycin / Q000494:pharmacology; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D000860:Hypoxia / Q000188:drug therapy* / Q000378:metabolism; D014700:Verapamil / Q000494:pharmacology*; D014841:von Willebrand Factor / Q000378:metabolism*
chemical_list: D014841:von Willebrand Factor; D000001:Calcimycin; D014700:Verapamil