摘要
目的:观察藻酸双酯钠(Polysaccharide sulfate,PSS)对豚鼠单个心室肌细胞离子流的影响。方法:采用Ⅰ型胶原酶分离单个豚鼠心室肌细胞的方法,利用全细胞膜片箝记录技术,在不同箝制条件下,记录并分析了PSS对L-型Ca2+电流(ICa,L)、内向整流K+电流(IK1)的影响。结果:①PSS使ICa,L的激活时间常数变大,电流幅度减小,Ⅰ-Ⅴ曲线上移。在箝制电位为+10 mV时,PSS在6-9 min内使ICa,L的激活时间常数从(0.92±0.10)ms增加到了(1.15±0.11)ms(n=5,P<0.052);ICa,L的电流幅度从(16.80±1.71)pA/pF下降至(13.86±1.67)pA/pF(n=5,P<0.01)。②PSS可使IK1的内向成分和外向成分均增加。当箝制电位在-170 mV时,PSS能使IK1内向电流幅度从(224±16.17)pA／pF增加至(257±17.36)pA／pF(n=7,P<0.01);箝制电位在-50 mV时,PSS使IK1的外向电流幅度从(8.89±0.86)pA／pF增加至(10.38±1.18)pA／pF(n=7,P<0.05)。在反转电位附近时(-70--120 mV),PSS的作用不明显。PSS能使IK1的激活时间常数减小,当箝制电位在-160 mV时,激活时间常数从加药前的(1.05±0.11)ms减小到了加药后的(0.78±0.90)ms(n=7,P<0.01);同时,IK1的电导值变大,从(2.53±0.17)nS／pF增加到了(2.82 ±0.20)nS／pF(n=7,P<0.05)。结论:PSS对L-型Ca2+电流有抑制作用,对内向整?
Objective: To examine the effects of polysaccharide sulfate (PSS) on ionic currents in guinea pig ventricular myocytes. Methods : Single ventricular cells of guinea pigs were isolated with a collagenase( I-type) dispersion method, using whole-cell recording method to record L-type Ca 2+ current (ICa,L) and the inward rectifier K+ current(IK1) . Results : ① PSS increased the time constant of activation and decreased the current amplitude of ICa,L. ②PSS increased not only the inward component but also the outward component of the peak IK1 , PSS decreased the time constant of activation of IK1 and PSS increased the maximal slope conductance of IK1 . Conclusion: PSS decreases L-type Ca2+ current, increases the inward rectifier K+ current.
出处
《河南医学研究》
CAS
2004年第3期203-207,共5页
Henan Medical Research
关键词
PSS
豚鼠
藻酸双酯钠
心室肌细胞
内向
激活
K^+电流
外向
结论
目的
polysaccharide
ventricular myocytes
the patch-clamp technique
L-type Ca2+ current
the inward rectifier K+ current
