镰刀菌毒素DON对心肌细胞膜电位的影响及硒的保护效应  

Effect of deoxynivalenol on action potentials of cultured cardiomyocytes and the protective effects of selenium

作　　者：彭双清[1] 杨进生[1] 

机构地区：[1]军事医学科学院毒物药物研究所,北京100850

出　　处：《中华预防医学杂志》2003年第6期423-425,共3页Chinese Journal of Preventive Medicine

摘　　要：目的　观察镰刀菌毒素单端孢霉烯族化合物脱氧雪腐镰刀菌烯醇 (DON)对培养心肌细胞动作电位的影响及亚硒酸钠的保护效应。方法　取新生 1～ 2d龄Wistar大鼠 ,分离心肌细胞 ,培养基为 80 %DMEM与 2 0 %小牛血清 ,于 37℃ ,在含 5 %CO2 与 95 %空气的培养箱内进行培养 ,于培养后第 4天 ,引导心肌细胞动作电位为加入毒素前对照 ,然后向培养基中分别加入 5 0、10 0和 2 0 0mg/LDON ,以观察不同剂量DON对心肌细胞动作电位的影响。在培养基中加入含 0 5mg/L硒的亚硒酸钠 ,继续培养 16h后 ,观察硒对DON致心肌细胞膜电位改变的保护作用。结果　DON使心肌细胞去极化过程发生改变 ,动作电位 (APA)、最大除极速度 (Vmax)、超射 (OS)及阈电位 (TP)均减小 ,部分参数指标存在较明显的剂量效应关系。OS在DON为 5 0mg/L时出现增高现象。复极化过程的变化 ,复极动作电位时程 (APD)明显延长 ;最大舒张电位 (MDP)减小 ;动作电位发放频率 (APF)受到明显的抑制 ,且存在明显的剂量依存关系。在培养基中加入含 0 5mg/L硒的亚硒酸钠 ,继续培养 16h后 ,2 0 0mg/LDON对其心肌细胞动作电位的抑制作用明显减弱 ,但部分参数 (APA、Vmax、OS、TP、APD90 及APF)没有完全保持在正常对照组水平 ,亚硒酸钠不能完全对抗DON引起的心肌细胞?Objective To study the effect of deoxynivalenol (DON),a mycotoxin produced by Fusarium graminearum,on action potentials of cultured cardiomyocytes and the possible protective effects of sodium selenite. Methods Ventricular myocytes from neonatal Wistar rats were cultured,and the transmembrane action potentials were recorded with glass microelectrodes before and after addition of DON at different concentrations. The cultured cardiomyocytes were pretreated with 0.5 mg/L selenium (as sodium selenite) to observe the protective effects of selenium against the effects of DON. Results DON at concentrations of 50,100 and 200 mg/L decreased the action potential parameters including action potential amplitude (APA),overshoot (OS),threshold potential (TP),maximum rate of depolarization (Vmax) and action potential discharging frequency (APF),and prolonged the action potential duration of 10%,50% and 90% repolarization (APD 10,APD 50 and APD 90). Some of the parameters,such as APA,Vmax,APD and APF,changed in a concentration-dependent manner. The cultured cardiomyocytes pretreated with 0.5 mg/L of selenium for about 16 h presented only slight changes in action potential parameters induced by 200 mg/L DON. Conclusions DON inhibit the membrane action potentials of cardiomyocytes ,suggesting DON may interfere with the transmembrane movement of Ca 2+ and K+,and sodium selenite may decrease the toxic effect of DON on cultured cardiomyocytes。

关 键 词：镰刀菌毒素 DON 心肌细胞 膜电位 硒 保护效应 单端孢霉烯族化合物 脱氧雪腐镰刀菌烯醇 

分 类 号：R541[医药卫生—心血管疾病]