Mutant human α1β1(T262Q) GABAA receptors are directly activated but not modulated by pentobarbital
Mutant human α1β1(T262Q) GABAA receptors are directly activated but not modulated by pentobarbital
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DOI：
10.1016/s0014-2999(99)00710-4
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发表时间：
1999-12-03
影响因子：
5
通讯作者：
Birnir, B
中科院分区：
文献类型：
--
作者：
Dalziel, JE;Cox, GB;Birnir, B
戊巴比妥激活GABA（A）受体并增强GABA激活电流。在β（1）亚基α（1）β（1）（T12 ′ Q）的12 ′位第二跨膜区中的苏氨酸残基（262）是戊巴比妥增强作用所必需的。我们研究了是否T12 'Q突变受体表达的草地贪夜蛾（SF 9）细胞响应戊巴比妥的直接激活。在突变体和野生型受体，戊巴比妥（100 μ M至1 mM）引起的电流响应。戊巴比妥的EC 50值相似; α（1）β（1）和α（1）β（1）（T12 'Q）受体分别为119和158 μ M。结果表明，可以区分戊巴比妥的激动和增强作用，表明这些作用涉及不同的机制。(C)1999 Elsevier Science B. V.保留所有权利。
Pentobarbital activates GABA(A) receptors and enhances GABA-activated currents. A threonine residue (262) in the second membrane spanning region at the 12' position in the beta(1) subunit, alpha(1)beta(1)(T12'Q), is necessary for the potentiating action of pentobarbital. We examined whether T12'Q-mutated receptors expressed in Spodoptera frugipedra (Sf 9) cells responded to direct activation by pentobarbital. In both mutant and wild type receptors, pentobarbital (100 mu M to 1 mM) evoked a current response. The pentobarbital EC50 values were similar; 119 and 158 mu M for alpha(1)beta(1) and alpha(1)beta(1)(T12'Q) receptors, respectively. The results show it is possible to discriminate between agonistic and potentiating effects of pentobarbital suggesting these actions involve separate mechanisms. (C) 1999 Elsevier Science B.V. All rights reserved.