Ho C L, Hwang L L, Lin Y L, Chen C T, Yu H M, Wang K T
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC.
Eur J Pharmacol. 1994 Jul 11;259(3):259-64. doi: 10.1016/0014-2999(94)90652-1.
Mastoparan B is a cationic, amphiphilic tetradecaeptide (LKLKSIVSWAKKVL-CONH2) isolated from the venom of the hornet Vespa basalis. Intravenous injection of the peptide into rats caused a profound depression of blood pressure and cardiac function, which was inhibited by cyproheptadine, reserpine and multiple doses of compound 48/80, but not by diphenhydramine and cromolyn. Mastoparan from Paravespula lewisii showed little cardiovascular inhibitory activity. A synthetic mastoparan B analog in which lysine at position 2 was replaced by asparagine showed a marked decrease in the cardiovascular depressor effects, while replacing lysine at position 4, 11 or 12 with leucine did not cause a significant reduction in these effects. Replacing lysine at position 12 with leucine even caused a more sustained depressor effect. However, the analog in which lysines at positions 11 and 12 were replaced by leucine lost its cardiovascular inhibitory activity. Replacing tryptophan at position 9 with phenylalanine in mastoparan B did not affect its activity. It is concluded that mastoparan B is involved in the cardiovascular disturbances induced by the hornet venom. Lysine at position 2 is a critical residue for the cardiovascular effects of mastoparan B. A peptide molecule with two lysine residues, one located close to the amino terminus and the other near the carboxyl end of the peptide, appears to be the optimal structure for eliciting the cardiovascular depressor effects.
蜂毒肽B是一种阳离子型两亲性十四肽（LKLKSIVSWAKKVL-CONH2），从黄蜂基胡蜂的毒液中分离得到。给大鼠静脉注射该肽会导致血压和心脏功能严重下降，这种作用可被赛庚啶、利血平和多剂量的化合物48/80抑制，但不能被苯海拉明和色甘酸钠抑制。来自刘易斯黄胡蜂的蜂毒肽显示出很小的心血管抑制活性。一种将第2位赖氨酸替换为天冬酰胺的合成蜂毒肽B类似物，其心血管降压作用显著降低，而将第4、11或12位赖氨酸替换为亮氨酸不会导致这些作用显著降低。将第12位赖氨酸替换为亮氨酸甚至会导致更持久的降压作用。然而，将第11和12位赖氨酸替换为亮氨酸的类似物失去了其心血管抑制活性。在蜂毒肽B中，将第9位色氨酸替换为苯丙氨酸不影响其活性。得出结论，蜂毒肽B参与黄蜂毒液诱导的心血管紊乱。第2位赖氨酸是蜂毒肽B心血管效应的关键残基。一个具有两个赖氨酸残基的肽分子，一个位于肽的氨基末端附近，另一个靠近羧基末端，似乎是引发心血管降压作用的最佳结构。
