| 细胞外Ba2+对大鼠心肌细胞L型钙通道的影响 |
| |
| 引用本文： | 孟红旭,姚明江,任钧国,刘建勋.细胞外Ba2+对大鼠心肌细胞L型钙通道的影响[J].中国应用生理学杂志,2018,34(3):218-222. |
| |
| 作者姓名： | 孟红旭 姚明江 任钧国 刘建勋 |
| |
| 作者单位： | 中国中医科学院西苑医院基础医学研究所, 中药药理北京市重点实验室, 北京, 100091 |
| |
| 基金项目： | 中国中医科学院自助选题项目（zz070821）；973计划课题（2015CB554405）；中国中医科学院创新团队建设项目（YS1303） |
| |
| 摘 要： | 目的：观察细胞外Ba2+对记录大鼠心肌细胞L型钙通道的影响。方法：采用急性酶解分离法获得大鼠的单个心肌细胞，使用全细胞膜片钳技术记录L型钙通道电流。采用Ba2+替换台式液中的Ca2+和直接向台式液中加入Ba2+（0~8 mmol/L），观察峰值电流15 min内的变化，数据采用5个以上细胞进行重复。结果：（1）台式液中的Ca2+被Ba2+替换后，L型钙通道电流的失活速率明显减慢（P<0.01）；在台式液中加入少量Ba2+（0.2，0.4 mmol/L）时L型钙通道电流的失活速率无明显改变（P>0.05），加入0.8 mmol/L Ba2+时失活速率明显减慢（P<0.05）。（2）与正常台式液比较，在细胞外液中加入Ba2+（0.2，0.4 mmol/L）峰值电流衰减减弱，其中10 min和15 min两个时间点衰减差异明显（P<0.01）。（3）在细胞外液中加入Ba2+可下移电流电压曲线，改变翻转电位，减弱丹酚酸A对钙电流的抑制强度，使量效关系曲线右移。结论：在细胞外液中加入一定浓度的Ba2+，能够减弱全细胞膜片钳技术记录大鼠心室肌细胞L型钙通道时出现的峰值电流衰减，改变通道的电压依赖特性，影响药物量效关系。
|
| 关 键 词： | 大鼠 心肌细胞 Ba2+ L型钙通道 全细胞膜片钳 |
| 收稿时间： | 2017-03-09 |
Effects of extracellular Ba2+ on L-type calcium current in rat ventricular cardiocytes |
| |
| MENG Hong-xu,YAO Ming-jiang,REN Jun-guo,LIU Jian-xun.Effects of extracellular Ba2+ on L-type calcium current in rat ventricular cardiocytes[J].Chinese Journal of Applied Physiology,2018,34(3):218-222. |
| |
| Authors: | MENG Hong-xu YAO Ming-jiang REN Jun-guo LIU Jian-xun |
| |
| Affiliation: | Institute of Basic Medical Sciences of Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing key Laboratory of Pharmacology of Chinese Materia Medica, Beijing 100091, China |
| |
| Abstract: | Objective: To observe the effect of extracellular Ba2+ on the recording L-type calcium channel of rat ventricular cardiocytes.Methods: Whole-cell patch clamp technique was used to record the currents of L-type calcium channels (ICa,L) in a single ventricular cardiocyte isolated from a rat heart by acute enzymatic digestion combined with mechanical method. Ba2+ was used to replace Ca2+ in Tyrode's solution, and Ba2+ (0~0.8 mmol/L) was directly added to Tyrode's solution to observe the change of the peak current within 15 minutes. The data were repeated with 5 cells or more.Results: ①The inactivation rate of ICa,L was slowed down significantly (P<0.01) with Ba2+ instead of Ca2+ gradually in Tyrode's solution. There was no change in the inactivation rate of ICa,L when the Ba2+ (0.2, 0.4 mmol/L) was added in the extracellular solution, but when 0.8 mmol/L Ba2+ was added, the inactivation rate would slow down significantly (P<0.01). ②Ba2+(0.2, 0.4 mmol/L) added in the extracellular solution could decrease the peak current attenuation. Compared with the group in Tyrode's solution, the peak current attenuation rate of the group in Ba2+ (0.2, 0.4 mmol/L) added in the extracellular solution was decreased significantly at the two time points (10 min, 15 min, P<0.01). ③The extracellular Ba2+ (0.4 mmol/L) could move the current-voltage curve down, change the reversal potential, weaken ICa,L inhibition induced by salvianolic acid A and right-shift concentration-response curve.Conclusion: The addition of Ba2+ to extracellular solution can attenuate the peak current decay, change the voltage-dependent characteristics of calcium channels and influence drug dose-effect relationship when whole-cell patch clamp technique is used to record L-type calcium channel of rat ventricular cardiocytes. |
| |
| Keywords: | rat ventricular myocytes Ba2+ L-type calcium current whole-cell patch clamp |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《中国应用生理学杂志》浏览原始摘要信息 |
|
点击此处可从《中国应用生理学杂志》下载全文 |
|
