论文部分内容阅读
目的 研究Ｎ甲基小檗胺对豚鼠单一心室肌细胞ＡＴＰ敏感钾电流的作用。方法 膜片钳制技术全细胞记录模式。结果 Ｎ甲基小檗胺抑制心室肌细胞ＡＴＰ敏感钾电流（ＩＫＡＴＰ）且具浓度依赖关系。指令电位为０ｍＶ时，３种浓度Ｎ甲基小檗胺（０－１，１，１０μｍｏｌ·Ｌ－１）可使ＩＫＡＴＰ分别由给药前的（０－４６±０－０９）ｎＡ，（０－４３±０－１５）ｎＡ和（０－４７±０－１０）ｎＡ减少至给药后的（０－３７±０－０７）ｎＡ（ｎ＝４，Ｐ＜０－０５），（０－２９±０－１８）ｎＡ（ｎ＝５，Ｐ＜０－０５）和（０－２１±０－０７）ｎＡ（ｎ＝４，Ｐ＜０－０５）。其抑制率分别为１８－８１％±６－１６％（Ｐ＜０－０５），４１－４７％±２４－０５％（Ｐ＜０－０５）和５５－００％±１２－９４％（Ｐ＜０－０５）。其它指令电位下的ＩＫＡＴＰ的改变也符合此趋势。结论 Ｎ甲基小檗胺阻断豚鼠心肌细胞ＡＴＰ敏感Ｋ＋钾通道。
Objective To investigate the effect of N-methyl berbamine on ATP-sensitive potassium currents in guinea pig single ventricle myocytes. Methods Patch clamping technique Whole cell recording mode. Results Nmethyl berbamine inhibited the ATP-sensitive potassium current (IKATP) in ventricular myocytes in a concentration-dependent manner. When the command potential is 0mV, three concentrations of N-methyl berbamine (0-1, 1, 10 μmol·L-1) can make IKATP from pre-dose (0-46±0-09) nA, respectively ( 0-43±0-15) nA and (0-47±0-10) nA decreased to (0-37±0-07) nA (n=4, P<0-05), (0 -29±0-18) nA (n=5, P<0-05) and (0-21±0-07) nA (n=4, P<0-05). The inhibition rates were 18-81%±6-16% (P<0-05), 41-47%±24-05% (P<0-05) and 55-00%±12-94% (P, respectively). <0-05). Changes in IKATP under other commanded potentials also follow this trend. Conclusion N-methyl berbamine blocks ATP-sensitive potassium channels in guinea pig cardiomyocytes.