Analogues of Neuroactive Polyamine Wasp Toxins That Lack Inner Basic Sites Exhibit Enhanced Antagonism Toward a Muscle-Type Mammalian Nicotinic Acetylcholine Receptor
作者:Kristian Strømgaard、Matthew J. Brierley、Kim Andersen、Frank A. Sløk、Ian R. Mellor、Peter N. R. Usherwood、Povl Krogsgaard-Larsen、Jerzy W. Jaroszewski
DOI:10.1021/jm9903747
日期:1999.12.1
resulting PhTX-343 analogues were purified and characterized, and their protolytic properties (stepwise macroscopic pK(a) values) were determined by (13)C NMR titrations. All analogues are fully protonated at physiological pH. The effects of these compounds on acetylcholine-induced currents in TE671 cells clamped at various holding potentials were determined. All of the analogues noncompetitively antagonized
Philanthotoxin-433(PhTX-433)是一种天然的多胺黄蜂毒素,是某些离子性受体的非竞争性拮抗剂。通过将N-(1-氧代丁基)酪氨酸与1,12-偶合偶联,合成了PhTX-343的六种类似物(天然产物的合成类似物),其中仲氨基被氧或亚甲基系统取代。十二烷二胺,4,9-二氧杂-1、12-十二烷二胺或经过适当保护的二胺和三胺,后者可通过多步合成法获得。纯化和表征所得的PhTX-343类似物,并通过(13)C NMR滴定确定其蛋白水解性质(逐步宏观pK(a)值)。所有类似物均在生理pH下完全质子化。确定了这些化合物对固定在各种保持电位下的TE671细胞中乙酰胆碱诱导的电流的影响。所有类似物都以浓度,时间和电压依赖性方式非竞争性地拮抗烟碱乙酰胆碱受体(nAChR)。在存在或不存在类似物的情况下,比较乙酰胆碱诱导的电流的振幅,在其峰值处和施加1 s末。大多数类似物与PhTX-343的效