Stolc S
Institute of Experimental Pharmacology, Slovak Academy of Sciences, Bratislava.
Gen Physiol Biophys. 1988 Apr;7(2):177-89.
Effects of procaine, trimecaine, and a new carbanilate local anesthetic, carbizocaine, on early sodium inward current and fast and slow components of potassium outward current in the membrane of the rat dorsal root ganglion neuron were studied using the internal dialysis and potential clamp techniques. All the currents studied were depressed in the presence of the drugs tested. However, for inhibition of the inward current concentrations lower by approximately one to more than two orders were sufficient compared to those required for similar inhibition of the outward currents. Carbizocaine was the most effective, procaine the least effective drug. Almost identical ratios of the negative logarithms of mean effective concentrations for blocking the inward and the outward current respectively, were found for each of the drugs tested. None of the drugs could be characterized as a specific blocker of sodium or potassium channels. It is concluded that the mechanisms of action of these three local anesthetics in all the three types of ion channels studied in the neuronal membrane are very similar regardless of both the type of the chemical bond in the intermediary chain of the molecules (ester, anilide, carbanilate) and the structure of the aromatic moiety, or the absolute potency of the drug.
采用内部透析和电压钳技术，研究了普鲁卡因、三甲卡因以及一种新型氨基甲酸酯类局部麻醉药卡比佐卡因对大鼠背根神经节神经元膜早期钠内向电流以及钾外向电流的快速和慢速成分的影响。在所测试的药物存在时，所有研究的电流均受到抑制。然而，与抑制外向电流所需的浓度相比，抑制内向电流所需的浓度低约1至2个数量级以上就足够了。卡比佐卡因是最有效的药物，普鲁卡因是最无效的药物。在所测试的每种药物中，分别阻断内向电流和外向电流的平均有效浓度的负对数几乎具有相同的比值。没有一种药物可被表征为钠通道或钾通道的特异性阻滞剂。得出的结论是，这三种局部麻醉药在神经元膜中所研究的所有三种类型离子通道中的作用机制非常相似，无论分子中间链中的化学键类型（酯键、酰胺键、氨基甲酸酯键）、芳香部分的结构如何，也无论药物的绝对效力如何。
