摘要
目的和方法：本实验采用全细胞膜片钳技术，以Ｌ型钙通道电流为指标，分别观察正常时、异丙肾上腺素（Ｉｓｏｐｒｅｎａｌｉｎｅ，ＩＳＯ）致损时及先加铜后致损时的豚鼠心室肌细胞钙电流的变化。结果：正常豚鼠心室细胞有一内向的电压依赖性钙电流，其最大峰电流（Ｉｐｅａｋ）为４６０±９８ｐＡ，可被维拉帕米阻断；细胞经１μｍｏｌ／ＬＩＳＯ损伤后，可使此内向钙电流明显增强，Ｉｐｅａｋ为１７００±４６０ｐＡ，与损伤前相比差异显著（Ｐ＜０．０５，ｎ＝４），同时此电流的ＩＶ曲线峰值左移，镜下细胞出现明显的形态学改变。先给予１μｍｏｌ／Ｌ硫酸铜溶液灌流２０ｍｉｎ后，由ＩＳＯ损伤引起的内向钙电流的幅度降低，Ｉｐｅａｋ为６８５±１２０ｐＡ，与ＩＳＯ损伤相比，差异显著（Ｐ＜０．０５，ｎ＝４）。结论：ＩＳＯ可使豚鼠心室肌细胞Ｌ型通道电压依赖性钙电流明显增强，铜离子可对抗由ＩＳＯ引起的钙电流增强。
Abstract Aim and Methcds:To observe the influence of Isoprenaline (ISO) and copper on the L type calcium channel current in myocyte of guinea pig with whole cell configutation of patch clamp technique, so as to elucidate the ionic mechanism of copper' protective effect on injuried myocytes. Results:The normal single myocyte of guinea pig has a small inward voltage dependant trans membrane ionic current, which with the blockage of Verapamil is confirmed as calcium current and the maxium peak current is 460±98pA,As 1 μ mol/L ISO was added into the chamber, we found that the inward calcium current was significently increased (Ipeak=1700±460 pA, P <0. 05, n =4). Under microscope the cell showed apparent morphogic alteration. When the myocytes was preperfused with Tyrode' solution containing 1 μ mol/L CuSO 4, the amplitude of calcium current induced by ISO was decreased markedly(Ipeak=685±120 pA, P <0. 05, n =4). Conclusion: ISO can cause the significent increase of inward calcium current in single myocyte of guinea pig, after the preparation with copper, cell can defence the injury. copper; patch clamp; L type Calcium current; ISO
出处
《中国应用生理学杂志》
CAS
CSCD
1999年第1期18-21,共4页
Chinese Journal of Applied Physiology
