培养大鼠搏动心肌细胞在缺氧和复氧时的电生理观察

THE ELECTROPHYSIOLOGICAL OBSERVATION OF HYPOXIA AND REOXYGENATION INJURY ON RAT BEATING HEART CELLS IN CULTURE

应用细胞内微电极技术记录到37个培养大鼠搏动心肌细胞充氮前后和复氧后的电活动参数。结果提示:充氮10min后,最大舒张电位(MDP),最大除极速度(V_(max)),动作电位振幅(APA)和动作电位时程(APD)等参数明显降低;自发节律增快,并出现多种形式的节律失常。83.8％细胞在充氮后30min内停搏,16.2％在50min左右停搏。复氧后,86.5％细胞在5min内复跳,13.5％未能复跳;12.5％复跳细胞在复跳10min内再次停搏。复跳细胞的各项电活动参数在30min内未能恢复到充氮前水平(p<0.05),且呈现不同程度的各类异常电活动。本结果对进一步研究心肌细胞缺氧和复氧损伤有一定意义。

An intracellular microelectrode technique was used to evaluate the changes of electric activities of cultured rat beating heart cells with hypoxia and reoxygenation injury. The results (n = 37) showed that hypoxia caused decreases in the maximal diastolic potential (MDP), Vmax . overshoot (OS) and action potential amplitude (APA), shortening in action potential duration (APD50 and APD100), increase in beating frequency and lots of multiform arrhythmias. After exposure to pure nitrogen 31 cells (83.8%) stopped beating within 30 min while 6 cells (16.2%) stopped beating within 50 min or so. Most cells (86.5%) resumed beating following treatment with oxygen (95%) and carbon dioxide (5%) for 5 min, whereas the values of electric activity parameters of reheating cell during reoxygenation for 30 min were lower than those of normoxic cells (p<0.05). In addition, all reheating cells showed multiform arrhythmias. However, 5 cells (13.5%) could not reheat following reoxygenation and 4 cells (12.5%) stopped beating again within 10 min after reoxygenation.The results indicated that this model exhibited some significance for studying the elec-trophysiological changes in hypoxia and reoxygenation injury of heart cells.