GJA1 and Arrhythmia: Indeed, the acclimation of hairless SHR males to an ambient temperature that is below thermoneutrality [19] resulted in the attenuation of Cx43 downregulation, which may contribute to their reduced susceptibility to life-threatening arrhythmias (as indicated by a higher VF threshold) and improved heart function (as indicated enhanced by an enhanced ejection fraction).