Herrling P L, Misbach-Lesenne B
Naunyn Schmiedebergs Arch Pharmacol. 1982 Jul;320(1):20-5. doi: 10.1007/BF00499066.
Acetylcholine was applied to isolated crayfish hindguts and caused dose-dependent increases in its contractile force. These effects were blocked by muscarinic but not by nicotinic antagonists. Dopamine, noradrenaline, enkephalin or GABA agonists had either no effect or one distinct from the action of acetylcholine. Of a number of antischizophrenic drugs, clozapine had the strongest antimuscarinic action with a pA 2 value of 7.5, followed by thioridazine with a pA 2 value of 6.7. All other drugs of the phenothiazine, butyrophenone or benzamide type were ineffective. From these results, it was concluded that the crayfish hindgut is a very reliable and simple bioassay for muscarinic actions of drugs. Clozapine was also applied by microiontophoresis to cat hippocampal neurons and its effects on carbachol-, acetylcholine- and glutamate-induced excitations was assessed. It displayed an inhibitory action on excitations induced by the cholinergic agents, but did not visibly affect those induced by glutamate. The fact that clozapine had strong antimuscarinic effects on the crayfish hindgut as well as on hippocampal neurons of a mammalian indicates a similarity between the muscarinic receptors in both tissues.
将乙酰胆碱应用于离体小龙虾后肠，可使其收缩力呈剂量依赖性增加。这些效应被毒蕈碱拮抗剂阻断，但未被烟碱拮抗剂阻断。多巴胺、去甲肾上腺素、脑啡肽或γ-氨基丁酸激动剂要么没有作用，要么作用与乙酰胆碱不同。在多种抗精神分裂症药物中，氯氮平具有最强的抗毒蕈碱作用，pA2值为7.5，其次是硫利达嗪，pA2值为6.7。所有其他吩噻嗪类、丁酰苯类或苯甲酰胺类药物均无效。从这些结果可以得出结论，小龙虾后肠是一种非常可靠且简单的药物毒蕈碱作用生物测定法。氯氮平还通过微离子电泳法应用于猫海马神经元，并评估其对卡巴胆碱、乙酰胆碱和谷氨酸诱导的兴奋作用的影响。它对胆碱能药物诱导的兴奋表现出抑制作用，但对谷氨酸诱导的兴奋没有明显影响。氯氮平对小龙虾后肠以及哺乳动物海马神经元具有强烈的抗毒蕈碱作用，这一事实表明这两种组织中的毒蕈碱受体具有相似性。
