Stankovicová T, Stolc S, Szöcsová H, Benes L
Drugs Exp Clin Res. 1986;12(9-10):761-4.
The blocking activity and pH dependence of carbanilate local anaesthetics, carbisocaine and its homologues, were tested on isolated rat sciatic nerves at pH 6.0, 7.2 and 8.4. Carbisocaine blocked the compound action potential more strongly than the derivatives with shorter alkoxysubstituents. The blocking potency of shorter derivatives increased with the rise of external medium pH, whereas the activity of carbisocaine increased with decreasing external pH. Quaternary compounds applied in the external medium were able to block the action potential, but in higher concentrations and with a longer half-time than their tertiary analogues. The blocking potency of quaternary derivatives correlated well with the length of the alkoxysubstituent and thus also with their lipophilicity. Extracellular pH did not consistently change the inhibitory effect of quaternized derivatives. These observations support the view that the lipophilicity of local anaesthetics is one of the possible factors determining their anaesthetic activity and the pH dependence of their effect.
在pH值为6.0、7.2和8.4的条件下，对分离出的大鼠坐骨神经测试了氨甲酰苯胺类局部麻醉药、卡比佐卡因及其同系物的阻断活性和pH依赖性。卡比佐卡因比具有较短烷氧基取代基的衍生物更强烈地阻断复合动作电位。较短衍生物的阻断效力随外部介质pH值的升高而增加，而卡比佐卡因的活性随外部pH值的降低而增加。施加于外部介质中的季铵化合物能够阻断动作电位，但所需浓度更高，半衰期比其叔胺类似物更长。季铵衍生物的阻断效力与烷氧基取代基的长度密切相关，因此也与其亲脂性相关。细胞外pH值并未持续改变季铵化衍生物的抑制作用。这些观察结果支持了这样一种观点，即局部麻醉药的亲脂性是决定其麻醉活性及其作用pH依赖性的可能因素之一。
