Referenced in: none

Automatically associated channels: TRP , TRPA , TRPA1 , TRPM , TRPM8

Title: Temperature-dependent calcium-induced calcium release via InsP(3) receptors in mouse olfactory ensheathing glial cells.

Authors: Maren Stavermann, Kristina Buddrus, James A St John, Jenny A K Ekberg, Bernd Nilius, Joachim W Deitmer, Christian Lohr

Journal, date & volume: , 2012 May 25 , ,

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/22633850

Abstract
Cooling can induce Ca(2+) signaling via activation of temperature-sensitive ion channels such as TRPM8, TRPA1 and ryanodine receptor channels. Here we have studied the mechanism of cooling-evoked Ca(2+) signaling in mouse olfactory ensheathing cells (OECs), a specialized type of glial cells in the olfactory nerve layer of the olfactory bulb. Reducing the temperature from above 30°C to 28°C and below triggered Ca(2+) transients that persisted in the absence of external Ca(2+), but were suppressed after Ca(2+) store depletion by cyclopiazonic acid. Cooling-evoked Ca(2+) transients were present in mice deficient of TRPM8 and TRPA1, and were not inhibited by ryanodine receptor antagonists. Inhibition of InsP(3) receptors with 2-APB and caffeine entirely blocked cooling-evoked Ca(2+) transients. Moderate Ca(2+) increases, as evoked by flash photolysis of NP-EGTA (caged Ca(2+)) and cyclopiazonic acid, triggered InsP(3) receptor-mediated Ca(2+) release at 22°C, but not at 31°C. The results suggest that InsP(3) receptors mediate Ca(2+)-induced Ca(2+) release in OECs, and that this Ca(2+) release is temperature-sensitive and can be suppressed at temperatures above 28°C.