鲫鱼脑氨基酸类神经递质受体在两栖类卵母细胞中的表达  

AMINO ACID NEUROTRANSMITTER RECEPTORS OF CARP BRAIN EXPRESSED IN AMPHIBIAN OOCYTES

作　　者：朱辉[1] 朱幸[1] 包永德[1] 

机构地区：[1]中国科学院上海生理研究所

出　　处：《生理学报》1995年第1期1-10,共10页Acta Physiologica Sinica

基　　金：国家科学基金;中国科学院上海生命科学研究中心;生命科学联合开放实验室资助

摘　　要：两栖类卵母细胞表达系统经注射鲫鱼（Ｃａｒａｓｓｉｕｓｃａｒａｓｓｉｕｓ）脑ｍＲＮＡ后可表达多种神经递质受体和某些离子通道。本工作利用电压箝方法结合药理学手段对ＧＡＢＡ受体和谷氨酸离子型受体作了较详细的研究。结果表明，由ＧＡＢＡ诱发的电流反应中，约９０％由ＧＡＢＡＡ受体介导，剩余约１０％的成分对ＧＡＢＡＡ受体的专一性拮抗剂Ｂｉｃｕｃｕｌｌｉｎｅ不敏感，而ＧＡＢＡＢ受体的专一性激动剂Ｂａｃｌｏｆｅｎ不能引起电流反应，因此这部分受体特性与ＧＡＢＡＣ受体相似。表达的谷氨酸受体包括离子型受体和代谢型受体。离子型受体中除了少量ＮＭＤＡ受体，绝大部分属ＫＡ／ＡＭＰＡ受体亚型。在研究谷氨酸受体各种激动剂的相互作用时，发现ＮＭＤＡ能竞争性地压抑由ＫＡ诱发的电流，提示ＮＭＤＡ可能是ＫＡ／ＡＭＰＡ受体的弱拮抗剂。GABA receptor and inotropic glutamate receptors were expressed in amphibian oocytes and studied with the voltage-clamp technique and pharmacological method afterinjection of mRNA from carp (Carassius carassius) brains. It was found that about90% of the response to GABA was mediated by GABAA receptor, but there was alsoabout 10% of the response which was insensitive to bicuculline, a selective antagonist to GABAA receptor, baclofen, a selective agonist to GABAB receptor, had no effect on the injected oocytes. These observations suggest the existence of GABAC receptor. Subtypes of glutamate receptors, including NMDA subtype, KA/ AMPA subtype and metabotropic glutamate receptors were also expressed and the dose-response relationswere studied. Furthermore, we found that NMDA competitively suppressed the currentresponse to KA, suggesting that NMDA probably was a weak antagonist of the KA/AMPA receptor.

关 键 词：鲫鱼 脑 mRNA 表达 神经递质 两栖纲 卵母细胞 

分 类 号：Q959.468[生物学—动物学] Q959.505