缺氧预处理对缺氧复氧乳鼠心室肌细胞游离钙的影响  

Effects of Late Preconditioning on Intracellular Free Calcium Concentration in Cardiac Myocytes of the Neonatal Rat Undergone Anoxia-Reoxygenation Injury

作　　者：郑杨[1] 佟倩[1] 张文杰[1] 迟宝荣[1] 李京沙[1] 

机构地区：[1]吉林大学第一医院心内科,吉林长春130021

出　　处：《中国心脏起搏与心电生理杂志》2005年第4期291-294,共4页Chinese Journal of Cardiac Pacing and Electrophysiology

基　　金：吉林省科技发展计划基金资助项目(吉发合字990581-1)

摘　　要：观察缺氧预处理对缺氧复氧乳鼠心室肌细胞游离钙的影响。建立培养乳鼠心肌细胞缺氧/复氧损伤模型。设正常对照组(A组)、缺氧复氧组(B组)、缺氧预适应组(C组)。经Flou-3/AM负载染色后,采用流式细胞分析技术,测定细胞内钙离子浓度;利用膜片钳技术,观察L型钙通道和钠钙交换电流的变化。结果:①与A组比较,B组可显著增加细胞内的游离钙离子浓度(P<0.01);L型钙电流密度明显下降,I-V曲线上移,半数失活电压(V1/2)减小,ICa,L失活曲线明显左移,而Na+/Ca2+交换电流显著增加。②与B组比较,C组可减轻缺氧再灌注时[Ca2+]i增加(P<0.01);可减轻再灌注对L型钙电流的抑制,使I-V曲线下移程度减轻,V1/2增加及稳态失活曲线的右移;减少Na+/Ca2+交换电流的增加;③与A组比较,C组钙内流和Na+/Ca2+交换电流有轻度增加(P<0.05)。结论:缺氧预处理使缺氧/复氧造成的[Ca2+]i增高的程度减轻,是通过抑制Na+/Ca2+交换电流的增加实现的。To observethe effects of late preconditioning on intracellular free calcium concentration （ [ Ca^2 ＋ ] i ） in cardiac myocytes of the neonatal rat undergone anoxia-reoxygenation injury. Methods： The anoxia-reoxygenation models in cultured ventricular myocytes of neonatal rat were established and divided into ①normal ;② anoxia-reoxygenation and ③anoxia-preconditioning （5 min anoxia ＋ 5 min reoxygenation） groups. By using Flou-3 AM loading and flow cytometry technique, the [ Ca^2＋ ]i were observed, and whole-cell patch clamp technique was used to record the L-type calcium current and Na^＋/Ca^2＋ exchange current. Results ： ① Compared to normal group, [ Ca^2 ＋ ] i of the anoxia- reoxygenation group increased significantly （ P 〈 0. 01 ） and L-type calcium current density decreased （P 〈0.01 ）, and the current-voltage curve moved up, and the inactivation curve moved left and Na^ ＋/Ca^2 ＋ exchange current increased in anoxia-reoxygenation. ② Compared to anoxia-reoxygenation group, [ Ca^2 ＋ ] i in the anoxia-precondition group significant decreased P 〈 0.01 ） ; and L-type calcium currem density significantly increased（P 〈 0.01 ） , and the current-voltage curve moved down, and the inactivation curve moved right and Na^ ＋/Ca^2＋ exchange current decreased. ③ Compared to normal oxygen condition, [ Ca^2 ＋ ]i and Na^ ＋/Ca^2＋ exchange current lightly increase in the anoxia-precondition group（ P 〈 0.05 ）. Conclusion ： Late precondition could decrease the [ Ca^2 ＋ ] i increase during anoxia-reoxygenation, and it restraintes the abnormal increasing of Na^ ＋/Ca^2＋ exchange current.

关 键 词：心血管病学 晚期预适应 游离钙 L型钙通道 钠钙交换电流 缺氧复氧 

分 类 号：R331.38[医药卫生—人体生理学]