Kowluru A, Seavey S E, Rabaglia M E, Metz S A
Department of Medicine, University of Wisconsin School of Medicine, Madison 53792.
Biochem Pharmacol. 1995 Jan 18;49(2):263-6. doi: 10.1016/s0006-2952(94)00489-7.
We examined whether mastoparan (MAS)-induced insulin secretion might involve the activation of nucleoside diphosphokinase (NDP kinase), which catalyzes the conversion of GDP to GTP, a known permissive factor for insulin secretion. MAS and MAS 7 (which activate GTP-binding proteins), but not MAS 17 (an inactive analog), stimulated insulin secretion from normal rat islets. In contrast to their specific effects on insulin secretion, MAS, MAS 7 and MAS 17 each stimulated formation of the phosphoenzyme-intermediate of NDP kinase, as well as its catalytic activity. These effects were mimicked by several cationic drugs. Thus, caution is indicated in using MAS to study cellular regulation, since some of its effects appear to be non-specific, and may be due, in part, to its amphiphilic, cationic nature.
我们研究了mastoparan（MAS）诱导的胰岛素分泌是否可能涉及核苷二磷酸激酶（NDP激酶）的激活，该酶催化GDP转化为GTP，而GTP是已知的胰岛素分泌允许因子。MAS和MAS 7（激活GTP结合蛋白），但不是MAS 17（无活性类似物），刺激正常大鼠胰岛分泌胰岛素。与它们对胰岛素分泌的特异性作用相反，MAS、MAS 7和MAS 17均刺激NDP激酶的磷酸酶中间体形成及其催化活性。几种阳离子药物模拟了这些作用。因此，在使用MAS研究细胞调节时需谨慎，因为它的一些作用似乎是非特异性的，部分可能归因于其两亲性阳离子性质。
