Citrus bergamia Risso Elevates Intracellular Ca~(2+) in Human Vascular Endothelial Cells due to Release of Ca~(2+) from Primary Intracellular Stores

摘要

The purpose of the present study is to examine the effects of essential oil of Citrus bergamia Risso (bergamot, BEO) on intracellular Ca~(2+) in human umbilical vein endothelial cells. Fura-2 fluorescence was used to examine changes in intracellular Ca~(2+) concentration [Ca~(2+)]_i . In the presence of extracellular Ca~(2+), BEO increased [Ca~(2+)]_i , which was partially inhibited by a nonselective Ca~(2+) channel blocker La~(3+). In Ca~(2+)-free extracellular solutions, BEO increased [Ca~(2+)]_i in a concentration-dependent manner, suggesting that BEO mobilizes intracellular Ca~(2+). BEO-induced [Ca~(2+)]_i increase was partially inhibited by a Ca~(2+)-induced Ca~(2+) release inhibitor dantrolene, a phospholipase C inhibitor U73122, and an inositol 1,4,5-triphosphate (IP_3)-gated Ca~(2+) channel blocker, 2-aminoethoxydiphenyl borane (2-APB). BEO also increased [Ca~(2+)]_i in the presence of carbonyl cyanide m-chlorophenylhydrazone, an inhibitor of mitochondrial Ca~(2+) uptake. In addition, store-operated Ca~(2+) entry (SOC) was potentiated by BEO. These results suggest that BEO mobilizes Ca~(2+) from primary intracellular stores via Ca~(2+)-induced and IP3-mediated Ca~(2+) release and affect promotion of Ca~(2+) influx, likely via an SOC mechanism.