Loose-patch方法及其诱发的钙火花

Ca^(2+) sparks evoked by loose-patch method

目的 :采用Loose patch方法在心室肌单细胞上诱发出钙火花并探讨其主要特征 ,并与以往有关的研究结果作比较分析 .方法 :Loose patch方法 ,即非紧密封接的细胞贴附式低阻抗膜片钳制技术和共聚焦显微镜钙成像技术相结合的方法 .结果 :Loose patch方法可以较高的概率 (72 .2 % )成功地诱发钙火花 ;其诱发的平均钙火花的幅度为 (1 .0 7± 0 .0 6 )(单位为△F/F0 ,其中F0 为静息时的钙荧光强度 ) ;空间范围为 (1 .4 4± 0 .0 3) μm ;n =1 2 4 .结论 :Loose patch方法可在保证膜上的L型钙通道与胞内相邻近的Ryanodine受体之间正常的信息耦联关系的前提下 ,定点诱发钙火花 ,并通过共聚焦显微镜钙成像技术实现实时准确记录 .这对于明确钙火花的特征 ,准确理解兴奋

AIM: To investigate the main characteristics of cardiac Ca 2+ sparks evoked by loose-patch method. METHODS: Loose-seal patch-clamp combined with confocal microscopic Ca 2+ imaging (Loose-patch Method) was used. RESULTS: The probability for the Loose-patch Method to evoke in-focus Ca 2+ sparks was 72.2%, which was much higher than the activation of spontaneous Ca 2+ sparks. The amplitude for the averaged Ca 2+ sparks evoked by Loose-patch Method was (1.07±0.06) (in ΔF/F 0, the normalized fluorescence, where F 0 denotes the resting fluorescence) and the averaged spatial width was (1.44±0.03) μm ( n =124). CONCLUSION: Loose-patch Method, while maintaining the normal signaling coupling between L-type Ca 2+ channel and ryanodine receptors, can evoke Ca 2+ sparks and the characteristics of Ca 2+ sparks by activating Ca 2+ release locally and in-focus can be recorded by confocal microscope.