Gene expression of thermosensitive TRP ion channels in the rat brain structures: Effect of adaptation to cold

• The expression of the thermosensitive TRP ion channel genes was more expressive in the hypothalamus.
• In brain genes of warm sensitive TRP ion channels were more expressed than cold sensitive ones.
• Long-term cold adaptation decreases the expression of Trpv3 gene in hypothalamus specifically.

The gene expression of the six best known thermosensitive transient receptor potential (TRP) ion channels (TRPV1, TRPV2, TRPV3, TRPV4, TRPA1, and TRPM8) was studied by the method of quantitative reverse transcription-polymerase-chain-reaction (RT-PCR) in different brain regions in rats, adapted and not adapted to cold. The expression of the investigated genes was identified in all the examined brain regions (hypothalamus, frontal cortex, hippocampus and midbrain). It was found rather high expression of the genes of warm sensitive ion channels was activated at temperatures above 30° C, in contrast, the gene expression level of cold sensitive TRPM8 and TRPA1 proved to be much lower. The expression of the genes of thermosensitive TRP ion channels was, mostly, greater in the hypothalamus than in the other brain regions.Comparison of the gene expression of all TRP ion channels in every investigated brain structures showed that after long-term adaptation to cold the decrease in Trpv3 gene expression was observed only in the hypothalamus, i.e. adaptive change is hypothalamic specific. Obtained results may evidence that thermosensitive TRP ion channels can be involved in the mechanisms of thermal adaptation at the level of gene expression.