鸡视网膜谷氨酸受体和GABA受体在两栖类卵母细胞中的表达

本工作利用两栖类卵母细胞作为功能表达系统，对鸡视网膜中的谷氨酸受体和ＧＡＢＡ受体的类型和基本性质进行了研究。在注射鸡视网膜ｍＲＮＡ的卵母细胞上，谷氨酸受体有明显的表达。Ｌ－Ｇｌｕ及其类似物ＫＡ，ＡＭＰＡ，ＱＡ都毫无例外地能诱导卵母细胞产生快速平滑的去极化电流，而ＮＭＤＡ，Ｌ－ＡＰ４，ＡＣＰＤ以及天冬氨酸不能诱导明显的电流反应。并且ＡＭＰＡ，ＱＡ对ＫＡ反应存在一定的抑制作用，提示ＡＭＰＡ，ＱＡ可能与ＫＡ作用于同一受体。抑制性氨基酸ＧＡＢＡ的受体被证明大部分为ＧＡＢＡＡ亚型，但有小部分的ＧＡＢＡ反应不能为荷包牡丹碱（ｂｉｃｕｃｕｌｌｉｎｅ）所阻断。

GLUTAMATE RECEPTOR AND GABA RECEPTOR EXPRESSED IN AMPHIBIAN OOCYTES AFTER INJECTION OF CHICKEN RETINA mRNA

The glutamate receptor and GABA receptor of chicken retina were studied with the expression system of amphibian oocyte. Some important results were obtained:L-gluta mate, kainate, AMPA and quisqualate could all induce rapid and smooth depolarizing currents in oocytes. NMDA, L-AP4, trans-ACPD and L-aspartate had no effects. The antagonism of kainate response by AMPA and quisqulate was found, and it seemed that AMPA, quisqualate and KA could act on the same receptor. Comparing the responses to L-Glu and NMDA, it was found that the mRNA abundance of metabotropic gluta mate receptor and NMDA receptor in chicken retina was much lower than that of chicken brain. The GABA receptor in chicken retina was very different from that of bovine retina. And although about 10% of the GABA response was insensitive to bicuculline,but most GABA receptors in chicken retina were proved as GABAA receptors.