Re L, Di Sarra B
Pharmacol Res Commun. 1987 Feb;19(2):131-45. doi: 10.1016/0031-6989(87)90003-8.
The cholinomimetic activity of Cimetidine and Ranitidine has been demonstrated by several authors. In the aim to better understand the phenomenon, we analyse the miniature end-plate current decay time. The prolongation of the decay phase of the synaptic current induced by the "selective" H2-antagonist Ranitidine, and to a lesser extent and at higher concentrations by Cimetidine, resembles that of the cholinesterase inhibitors. These agents usually prolong the quantal conductance change having little or no effect on the channel lifetime. The results of our previous experiments, which data were obtained by analyzing the "voltage" events, either spontaneous or evoked, of a classic frog preparation, showed a marked alteration of the temporal parameters. These effects, obtained at higher drug concentrations than those used in the present work, are now better defined by deriving extracellularly the "current" events. The results are also compared with those obtained by assaying the cholinesterase inhibitor Eserine, under the same experimental conditions.
几位作者已证实西咪替丁和雷尼替丁具有拟胆碱活性。为了更好地理解这一现象，我们分析了微小终板电流的衰减时间。“选择性”H2拮抗剂雷尼替丁诱导的突触电流衰减相延长，西咪替丁在较高浓度时也有较小程度的延长，这类似于胆碱酯酶抑制剂的作用。这些药物通常会延长量子电导变化，对通道寿命影响很小或没有影响。我们之前的实验结果是通过分析经典青蛙标本自发或诱发的“电压”事件获得的，这些结果显示时间参数有明显改变。这些效应是在比本研究中使用的药物浓度更高的情况下获得的，现在通过细胞外记录“电流”事件能更好地明确这些效应。同时，在相同实验条件下，将结果与测定胆碱酯酶抑制剂毒扁豆碱所获得的结果进行了比较。
