摘要
目的 :观察氯化铝 (AlCl3)对豚鼠乳头状肌动作动位及其兴奋性的影响。方法 :利用细胞内微电极技术引导动作电位 (AP) ,经微机采集AP图形并测算跨膜电位各参数。结果 :①AlCl30 .5 ,1,2 ,4mmol/L使动作电位复极5 0 %时程 (APD50 )和复极 10 0 %时程 (APD10 0 )先延长后大幅度缩短 ,呈现双相效应 ,其中AlCl32mmol/L作用 5min时使APD50 从 (182± 2 7)ms延长至 (2 0 2± 3 2 )ms(P <0 0 5 ) ,作用 3 0min时使APD50 缩短至 (14 4± 17)ms(P <0 0 1) ;②AlCl32 ,4mmol/L使动作电位幅度 (APA)及 0期最大除极速度 (Vmax)减小 ,兴奋性下降。结论 :AlCl3可能对Na+内流有抑制作用 ,对Ca2 +内流呈现先促进后抑制的双相效应。
Aim:To observe the effects of aluminium chloride (AlCl 3) on action potentials and excitability of guinea pig papillary muscles. Methods: Action potential(AP) was conducted by means of intracellar microelectrode technique. The pattern of AP was collected and the parameters of transmembrane potential were measured by computer.Results:AlCl 3 0.5,1,2,4 mmol/L caused a biphasic change in action potential duration at 50%(APD 50 ) and at 100%(APD 100 )repolarization,with early prolonging,followed by large shortening.AlCl 3 2mmol/L prolonged APD 50 from(182±27) ms to (202±32) ms ( P <0.05) 5 min after medication,shortened it to (144±17) ms ( P <0.01) 30 min after medication.AlCl 3 2,4 mmol/L reduced action potential amplitude(APA) and maximal depolarization rate of 0 phase (Vmax) , lowered the excitability.Conclusion:AlCl 3 may reduce the sodium current,enhance the calcium current early and decrease it later.
出处
《中国应用生理学杂志》
CAS
CSCD
1999年第3期258-260,共3页
Chinese Journal of Applied Physiology
关键词
铝
心肌
乳头状肌
动作电位
兴奋性
aluminium
myocardium
papillary muscles
action potentials
excitability
