Voltage dependence of the Ca2+ transient in endocardial and epicardial myocytes from the left ventricle of Goto Kakizaki type 2 diabetic rats
التاريخ
2018المؤلف
Al Kury, LinaSydorenko, Vadym
Smail, Manal M. A.
Qureshi, Muhammad Anwar
Shmygol, Anatoliy
Oz, Murat
Singh, Jaipaul
Howarth, Frank Christopher
...show more authors ...show less authors
البيانات الوصفية
عرض كامل للتسجيلةالملخص
Diabetes mellitus is a major global health disorder and, currently, over 450 million people have diabetes with 90% suffering from type 2 diabetes. Left untreated, diabetes may lead to cardiovascular diseases which are a leading cause of death in diabetic patients. Calcium is the trigger and regulator of cardiac muscle contraction and derangement in cellular Ca2+ homeostasis, which can result in heart failure and sudden cardiac death. It is of paramount importance to investigate the regional involvement of Ca2+ in diabetes-induced cardiomyopathy. Therefore, the aim of this study was to investigate the voltage dependence of the Ca2+ transients in endocardial (ENDO) and epicardial (EPI) myocytes from the left ventricle of the Goto–Kakizaki (GK) rats, an experimental model of type 2 diabetes mellitus. Simultaneous measurement of L-type Ca2+ currents and Ca2+ transients was performed by whole-cell patch clamp techniques. GK rats displayed significantly increased heart weight, heart weight/body weight ratio, and non-fasting and fasting blood glucose compared to controls (CON). Although the voltage dependence of L-type Ca2+ current was unaltered, the voltage dependence of the Ca2+ transients was reduced to similar extents in EPI–GK and ENDO–GK compared to EPI–CON and ENDO–CON myocytes. TPK L-type Ca2+ current and Ca2+ transient were unaltered. THALF decay of L-type Ca2+ current was unaltered; however, THALF decay of the Ca2+ transient was shortened in ENDO and EPI myocytes from GK compared to CON rat hearts. In conclusion, the amplitude of L-type Ca2+ current was unaltered; however, the voltage dependence of the Ca2+ transient was reduced to similar extents in EPI and ENDO myocytes from GK rats compared to their respective controls, suggesting the possibility of dysfunctional sarcoplasmic reticulum Ca2+ transport in the GK diabetic rat hearts.
المجموعات
- أبحاث الطب [1418 items ]