Effects of exosomes derived from cardiac fibroblasts pretreated with sevoflurane on ventricular electrical conduction in isolated rat hearts subjected to hypothermic ischemia-reperfusion: a multi-electrode array mapping technique for measurement / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effects of exosomes derived from cardiac fibroblasts pretreated with sevoflurane on ventricular electrical conduction in isolated rat hearts subjected to hypothermic ischemia-reperfusion (I/R) using the multi-electrode array mapping technique.Methods:Primary cardiac fibroblasts were extracted by differential adhesion in SPF Sprague-Dawley rats of either sex.Cardiac fibroblasts of passage 2-4 were treated with 2.5% sevoflurane for 1 h, and then cultured for 24-48 h to extract exosome.SPF healthy male Sprague-Dawley rats, aged 2-3 months, weighing 280-320 g, were divided into 3 groups ( n=8 each) using a random number table method: control group (group C), I/R group and sevoflurane-pretreated cardiac fibroblast-derived exosome+ IR group (group S+ IR). Hearts were perfused for 110-min equilibration in group C. After 20 min of equilibration, the perfusion was suspended for 60 min (global ischemia) followed by 30 min of reperfusion in IR and S+ IR groups.Exosomes 1 ml (200 μg) derived from cardiac fibroblasts pretreated with sevoflurane were injected through the tail vein at 48 h before surgery in group S+ IR, and the equal volume of normal saline was injected instead in C and IR groups.The cardiac conduction velocity (CV), conduction absolute inhomogeneity (P 5-95) and inhomogeneity index (P 5-95/P 50) were obtained at 20 min of equilibration (T 0) and 15 and 30 min of reperfusion (T 1, 2) using the microelectrode array attaching to the left ventricular surface of the isolated heart. Results:Compared with group C, CV was significantly decreased and P 5-95 and P 5-95/P 50 were increased at T 1 ( P<0.05), and no significant change was found at T 2 in group S+ IR ( P>0.05), and CV was significantly decreased and P 5-95 and P 5-95/P 50 were increased at T 1, 2 in group IR ( P<0.05). Compared with group IR, CV was significantly increased and P 5-95 and P 5-95/P 50 were decreased at T 1, 2 in group S+ IR ( P<0.05). Conclusions:Exosomes derived from cardiac fibroblasts pretreated with sevoflurane can improve ventricular electrical conduction in isolated rat hearts subjected to hypothermic I/R.