南天竹宁和罂粟碱对突触体膜酶有不同的修饰作用。

Nantenine and papaverine differentially modify synaptosomal membrane enzymes.

作者信息

Ribeiro R A, Rodríguez de Lores Arnaiz G

机构信息

Departamento de Farmacologia, Escola Paulista de Medicina, UNIFESP, São Paulo, Brazil.

出版信息

Phytomedicine. 2000 Jul;7(4):313-23. doi: 10.1016/s0944-7113(00)80050-1.

DOI:10.1016/s0944-7113(00)80050-1

PMID:10969726

Abstract

Papaverine (1-[(3,4-Dimethoxyphenyl) methyl]-6,7-dimethoxyisoquinoline) and nantenine (O-methyldomesticine) are chemically related isoquinoline alkaloids displaying similar dose-dependent sedative or convulsant effects, but seem to act differentially on synaptosomal membrane enzymes. Na+, K+-, Mg2+- and Ca2+-ATPase activities were inhibited by nantenine but not by papaverine, whereas acetylcholinesterase activity remained unchanged by nantenine but slightly enhanced by papaverine. Nantenine inhibited roughly both 20-50% Ca2+- and Mg2+-ATPase activities but 40-90% Na+, K+-ATPase activity. Kinetic analysis indicated that nantenine interacts with the substrate ATP for Ca2+-ATPase activity but that it competes with K+ for Na+, K+-ATPase activity. Given the roles of Na+, K+-ATPase and Ca2+-ATPase in cation transport and [Ca2+]i regulation, respectively, the inhibitory effect of nantenine upon these enzymes may explain its convulsant effect though not its sedative activity. The sedative action of both nantenine and papaverine is hardly attributable to an effect on the synaptosomal membrane enzymes assayed.

摘要

罂粟碱（1-[(3,4-二甲氧基苯基)甲基]-6,7-二甲氧基异喹啉）和南天竹碱（O-甲基土根碱）是化学相关的异喹啉生物碱，表现出相似的剂量依赖性镇静或惊厥作用，但似乎对突触体膜酶的作用有所不同。南天竹碱可抑制Na⁺、K⁺-、Mg²⁺-和Ca²⁺-ATP酶活性，而罂粟碱则无此作用；乙酰胆碱酯酶活性不受南天竹碱影响，但罂粟碱可使其略有增强。南天竹碱对Ca²⁺-和Mg²⁺-ATP酶活性的抑制率约为20%-50%，对Na⁺、K⁺-ATP酶活性的抑制率为40%-90%。动力学分析表明，南天竹碱与Ca²⁺-ATP酶活性的底物ATP相互作用，但与Na⁺、K⁺-ATP酶活性的K⁺竞争。鉴于Na⁺、K⁺-ATP酶和Ca²⁺-ATP酶分别在阳离子转运和[Ca²⁺]i调节中的作用，南天竹碱对这些酶的抑制作用可能解释其惊厥作用，但不能解释其镇静活性。南天竹碱和罂粟碱的镇静作用几乎不能归因于对所检测的突触体膜酶的影响。