Referenced in: none

Automatically associated channels: TRP , TRPA , TRPA1

Title: Polysulfides are possible H2S-derived signaling molecules in rat brain.

Authors: Yuka Kimura, Yoshinori Mikami, Kimiko Osumi, Mamiko Tsugane, Jun-Ichiro Oka, Hideo Kimura

Journal, date & volume: FASEB J., 2013 Jun , 27, 2451-7

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/23413359

Abstract
Accumulating evidence shows that hydrogen sulfide (H2S) has a variety of physiological functions. H2S is produced from cysteine by 3 sulfurtransferases. H2S, in turn, generates polysulfides, the functions of which are not well understood. H2S induces Ca(2+) influx in astrocytes, a type of glia. However, the receptor that mediates the response has not been identified. Here, we have shown that polysulfides induce Ca(2+) influx by activating transient receptor potential (TRP)A1 channels in rat astrocytes (EC50 91 nM, Hill coefficient value 1.77±0.26) and that the maximum response was induced at 0.5 μM, which is 1/320 of the concentration of H2S required to achieve a response of similar magnitude (160 μM, EC50 116 μM). TRPA1-selective agonists, allyl isothiocyanate and cinnamaldehyde, induced Ca(2+) influx, and responses to polysulfides were suppressed by TRPA1-selective inhibitors, HC-030031 and AP-18, as well as by siRNAs selective to TRPA1. The present study suggests that polysulfides are possible H2S-derived signaling molecules that stimulate TRP channels in the brain.