Effects of capsaicin on Ca(2+) release from the intracellular Ca(2+) stores in the dorsal root ganglion cells of adult rats.

We have investigated the effect of capsaicin on Ca(2+) release from the intracellular calcium stores. Intracellular calcium concentration ([Ca(2+)](i)) was measured in rat dorsal root ganglion (DRG) neurons using microfluorimetry with fura-2 indicator. Brief application of capsaicin (1 microM) elevated [Ca(2+)](i) in Ca(2+)-free solution. Capsaicin-induced [Ca(2+)](i) transient in Ca(2+)-free solution was evoked in a dose-dependent manner. Resiniferatoxin, an analogue of capsaicin, also raised [Ca(2+)](i) in Ca(2+)-free solution. Capsazepine, an antagonist of capsaicin receptor, completely blocked the capsaicin-induced [Ca(2+)](i) transient. Caffeine completely abolished capsaicin-induced [Ca(2+)](i) transient. Dantrolene sodium and ruthenium red, antagonists of the ryanodine receptor, blocked the effect of capsaicin on [Ca(2+)](i). However, capsaicin-induced [Ca(2+)](i) transient was not affected by 2-APB, a membrane-permeable IP(3) receptor antagonist. Furthermore, depletion of IP(3)-sensitive Ca(2+) stores by bradykinin and phospholipase C inhibitors, neomycin, and U-73122, did not block capsaicin-induced [Ca(2+)](i) transient. In conclusion, capsaicin increases [Ca(2+)](i) through Ca(2+) release from ryanodine-sensitive Ca(2+) stores, but not from IP(3)-sensitive Ca(2+) stores in addition to Ca(2+) entry through capsaicin-activated nonselective cation channel in rat DRG neurons.

Eun SY ，Jung SJ ，Park YK ，Kwak J ，Kim SJ ，Kim J ... -  《BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS》

Signaling mechanisms of down-regulation of voltage-activated Ca2+ channels by transient receptor potential vanilloid type 1 stimulation with olvanil in primary sensory neurons.

Wu ZZ ，Chen SR ，Pan HL 《NEUROSCIENCE》

Capsazepine elevates intracellular Ca2+ in human osteosarcoma cells, questioning its selectivity as a vanilloid receptor antagonist.

Teng HP ，Huang CJ ，Yeh JH ，Hsu SS ，Lo YK ，Cheng JS ，Cheng HH ，Chen JS ，Jiann BP ，Chang HT ，Huang JK ，Jan CR ... -  《LIFE SCIENCES》

Intracellular Ca2+ regulation in rat motoneurons during development.

Dayanithi G ，Mechaly I ，Viero C ，Aptel H ，Alphandery S ，Puech S ，Bancel F ，Valmier J ... -  《CELL CALCIUM》

Metabotropic glutamate receptor activation and intracellular cyclic ADP-ribose release Ca2+ from the same store in cultured DRG neurones.

Pollock J ，Crawford JH ，Wootton JF ，Seabrook GR ，Scott RH ... -  《CELL CALCIUM》