维拉帕米对自发性高血压大鼠左心室流出道自发慢反应电位的影响  

VER's Infuence on Spontaneous Slow Action Potential in the Left Ventricular Outflow Tract of Spontaneous Hypertensive Rats

作　　者：焦宏[1] 马建伟[1] 吕莉[1] 

机构地区：[1]河北北方学院生理教研室,河北张家口075000

出　　处：《河北北方学院学报（医学版）》2005年第5期17-19,共3页Journal of Hebei North University:Medical Edition

摘　　要：目的:探讨高血压大鼠左室流出道自发性慢反应电位0相和4相去极离子流中Ca2+的作用。方法:利用自发性高血压大鼠(SHR)的离体心脏,常规玻璃微电极细胞内记录方法和Ca2+离子通道阻断剂维拉帕米(VER),观测最大舒张电位(MDP)、0相除极幅度(APA)、0相最大除极速度(Vmax)、4相自动除极速度(VDD)、复极50%(APD50)和90%(APD90)的时间以及自发放电频率(RPF)。结果:1.0μmol/L维拉帕米可使该慢电位的APA、Vmax、VDD明显减小,RPF减慢(P<0.01);APD、APD90延长(P<0.05)。结论:(1)该区域的自发慢电位0相去极离子流主要为Ca2+内流。(2)4相去极离子流中,Ca2+内流起部分作用。Objective：To analysis the function of Ca^2＋ in the ionic mechanism underlying the phase 0 and phase 4 in the slow-response action of left ventricular outflow tract of spontaneous hypertensive rats. Methods：Spontaneous slow action potentials of the left ventricular outflow tract in heart were intracellularlly recorded with conventional manner. Electrophysiological parameters examined are： maximal diastolic potential （MDP）, amplitude of action potential（APA）,maximal rate of depolarization of phase 0 （Vmax）,velocity of diastolic depolarization of phase 4（VDD）,duration of 50% and 90% repolarization（APD50 and APD90 ）and rate of pacemaker firing （RPF）. Results： It was found that： 1.0μmol/L verapamil （VER） significantly decreased APA ,Vmax,VDD and RPF, （P〈0. 01） ,but APD and APD90 were significantly prolonged. Conclusion：The above results suggest that：（1）Generation of 0 phase in depolarization of slow-response activity in aortic vestibule from spontaneous hypertensive rats is contributed mainly to Ca^2＋ current. （2）In addition,the inward Ca^2＋ current plays some role in phase 4 depolarization.

关 键 词：维拉帕米 自发性高血压大鼠 左心室流出道 自发慢电位 

分 类 号：R331.3[医药卫生—人体生理学]