Altered expression of connexin43 contributes to the arrhythmogenic substrate during the development of heart failure in cardiomyopathic hamster

摘要

We used a strain of the Syrian cardiomyopathic hamster, UM-X7.1 (a derivative of the BIO14.6 strain), since its characteristic features of heart failure progression have been demonstrated in previous studies (36, 37); the animals show moderate compensated left ventricular (LV) contractile dysfunction at ages 10-20 wk and serious decompensated heart failure at ages beyond -24 wk. In the present study, we investigated stage-dependent changes in Cx43 expression in UM-X7.1 at ages 6-20 wk. Associated alterations in the electrophysiolog-ical properties and propensities for life-threatening arrhythmias were also investigated using a high-resolution optical mapping system. The results reveal that UM-X7.1 hamsters at age 20 wk, compared with golden hamsters (controls), exhibit a significant reduction in Cx43 expression (mRNA and protein) and moderate interstitial fibrosis.