Effect of olvanil (N-vanillyl-cis-9-octadecenoamide) on cytosolic Ca2+ increase in renal tubular cells.
In canine renal tubular cells, effect of olvanil, a presumed cannabinoid and vanilloid receptor modulator, on intracellular Ca2+ concentration ([Ca2+]i) was measured by using fura-2. Olvanil (5-100 microM) caused a rapid and sustained [Ca2+]i rise in a concentration-dependent manner. Olvanil-induced [Ca2+]i rise was prevented by 70 and 90% by removal of extracellular Ca2+ and La3+, respectively, but was not changed by dihydropyridines, verapamil and diltiazem. In Ca2+-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+-ATPase, caused a monophasic [Ca2+]i rise, after which the increasing effect of olvanil on [Ca2+]i was abolished; also, pretreatment with olvanil partly reduced thapsigargin-induced [Ca2+]i rise. U73122, an inhibitor of phoispholipase C, abrogated ATP-, but partly inhibited olvanil-, induced [Ca2+]i rise. Two cannabinoid receptor antagonists (AM251 and AM281; 5 microM) and a vanilloid receptor antagonist (capsazepine; 100 microM) did not alter olvanil (50 microM)-induced [Ca2+]i rise. These results suggest that olvanil rapidly increases [Ca2+]i in renal tubular cells, by stimulating both extracellular Ca2+ influx and intracellular Ca2+ release via mechanism(s) independent of stimulation of cannabinoid and vanilloid receptors.
Jan
Chung-Ren
CR
Department of Medical Education and Research, Kaohsiung Veterans General Hospital, 813, Kaohsiung, Taiwan.
Jiann
Bang-Ping
BP
Lu
Yih-Chau
YC
Chang
Hong-Tai
HT
Huang
Jong-Khing
JK
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002211:Capsaicin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism; D004285:Dogs; D017136:Ion Transport / Q000187:drug effects; D007684:Kidney Tubules / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects*
D000894:Anti-Inflammatory Agents, Non-Steroidal; C054256:olvanil; D002211:Capsaicin; D002118:Calcium