Hypergravity Increases the Number of Gene Transcripts of Mechanically Gated and Mechanosensitive Ion Channels in Rat Ventricular Cardiomyocytes

Abstract

Since hypergravity changes the morphological and physiological properties of the heart, it was assumed that the expression of ion channels that respond to cell stretching or compressing, mechanically gated channels (MGC) and mechanosensitive channels (MSC), would be affected. Using RNA transcriptome sequencing, the change in the number of transcripts for MGC and MSC genes was studied in isolated rat ventricular cardiomyocytes under 4g hypergravity for 5 days. It was shown for the first time that hypergravity induces changes in the number of transcripts of MGC genes: an increase for TRPC1, TRPC3, TRPM7, TRPP1 (PKD1), TRPP2 (PKD2), TMEM63A, TMEM63B, but a decrease for TRPV2, Piezo1, Piezo2. The number of MSC gene transcripts increases: TREK-1, Kir6.2, Nav1.5, Cav1.2, Cav1.3, Kv7.1, and Kv1.2. This potentially leads to an increase in the expression of MGC and MSC proteins leading to an increase in the net current and, as a result, pathological changes in the heart function.

Keywords: cardiomyocytes; hypergravity; mechanically gated and mechanosensitive channels; transcripts of channel genes.