Intracellular alkalinization augments capacitative Ca2+ entry in vascular smooth muscle cells

Autor: Ichiro Wakabayashi, Yoko Sotoda, Mikio Marumo
Rok vydání: 2003
Předmět:
Zdroj: Journal of cardiovascular pharmacology. 41(6)
ISSN: 0160-2446
Popis: Agonist-induced Ca 2+ influx ofvascular smooth muscle cells is thought to be triggered by depletion of intracellular Ca 2+ stores. This study investigated the effects of intracellular alkalinization on capacitative Ca 2+ entry in A7r5 rat aortic smooth muscle cells. Intracellular alkalinization was induced by NH 4 Cl. Transplasmalemmal Ca 2+ influx due to Ca 2+ store depletion induced by thapsigargin, which was abolished by pretreatment of the cells with SKF-96365 but not affected by that with verapamil, was significantly increased by pretreatment with NH 4 Cl. Neither 5-hydroxytryptamine-induced inositol monophosphate accumulation nor intracellular Ca 2+ release from its stores was affected by NH 4 Cl. These results suggest that intracellular alkalinization acts on the process(es) after depletion of Ca 2+ stores and facilitates capacitative Ca 2+ entry in vascular smooth muscle cells.
Databáze: OpenAIRE