摘要
[目的]探讨动脉粥样硬化(Atherosclerosis,AS)主动脉平滑肌细胞钙激活钾通道(Calcium-activatedPotas-siumChannel,KCa)变化及其对钙的敏感性。[方法]用酶消化法获取单个主动脉平滑肌细胞,通过膜片钳记录技术检测AS兔主动脉平滑肌细胞KCa通道的活性,并在浴液中分别加入不同浓度的Ca2+,以Pclamp7.0应用软件实时采样记录通道的开放概率(Po)、平均开放时间(To)、平均关闭时间(Tc)和电流幅值(Am),并以加钙前作对照观察上述参数的变化。[结果]AS组KCa通道的活性明显高于对照组;与加Ca2+前比较,对照组Po增加了(22.35±9.43)倍,而AS组仅增加了(5.31±0.42)倍(P<0.01)。[结论]AS兔血管平滑肌细胞KCa通道的活性明显增加,可能是AS血管发生代偿性扩张的机制之一;该通道对Ca2+的敏感性降低,可能是促进AS发展的因素之一。
[Objective]To investigate the changes of Calcium-activated Potassium (K_(Ca)) in aortic smooth muscle cells of New Zealand rabbits with atherosclerosis (AS) and sensitivity of the channels to Ca^(2+). [Methods]Single aortic smooth muscle cell was obtained after an enzymatical treatment. Patch clamp technique was used to record the single KCa channel current. The signal of channel open probability(Po), mean open dwell-time(To), mean close dwell-time(Tc) and current amplitude were recorded by the software of Pclamp 7.0. After adding different concentration of Ca^(2+) to bath solution respectively, the above parameters were observed again. [Results]Compared with that of the control group, the activity of K_(Ca) channels in the AS group was higher. After adding Ca^(2+), Po was increased by (22.35 9.43) times in the control group and (5.31 0.42) times in the AS group with statistical difference (P<0.01). [Conclusion]There was a higher K_(Ca) channel activity in atherosclerotic smooth muscle cells, which was possibly involved in the mechanism of compensatory vasodilation in AS. The sensitivity of K_(Ca) channels to Ca^(2+) decreased, which possibly promoted the formation and development of AS.
出处
《上海预防医学》
CAS
2005年第z1期6-9,共4页
Shanghai Journal of Preventive Medicine
关键词
动脉粥样硬化
膜片钳技术
钙激活钾通道
兔
<Keyword>Atherosclerosis
Calcium activated potassium channel
Patch clamp technique
Rabbit
