Wafford K A, Bain C J, Le Bourdelles B, Whiting P J, Kemp J A
Merck Sharp and Dohme Research Laboratories, Harlow, Essex, UK.
Neuroreport. 1993 Sep 30;4(12):1347-9. doi: 10.1097/00001756-199309150-00015.
cDNAs ENCODING NMDA receptor subunits have recently been cloned and been shown to have different distributions in the CNS. However, no studies on the possible in vivo combinations or subunit stoichiometry have yet been carried out. By combining human NR1 with rat NR2A and NR2C we have studied the pharmacological properties of three possible NMDA receptor subtypes; NR1 + NR2A, NR1 + NR2C and NR1 + NR2A + NR2C. By performing glycine concentration-response curves and comparing EC50s, it was possible to show that the NR1 + NR2A + NR2C receptor preferentially co-assembled when all three subunit cDNAs were present. This receptor had an affinity for glycine intermediate between that of NR1 + NR2A and NR1 + NR2C, but a similar Hill coefficient. Thus, two different NR2 subunits can combine in the same receptor, conferring unique pharmacological properties, suggesting that it is likely that two or more NR2 subunits co-assemble together in the same NMDA receptor complex.
编码N-甲基-D-天冬氨酸（NMDA）受体亚基的互补DNA（cDNA）最近已被克隆出来，并显示在中枢神经系统（CNS）中有不同的分布。然而，尚未开展关于体内可能的组合或亚基化学计量学的研究。通过将人NR1与大鼠NR2A和NR2C相结合，我们研究了三种可能的NMDA受体亚型的药理学特性；NR1 + NR2A、NR1 + NR2C和NR1 + NR2A + NR2C。通过绘制甘氨酸浓度-反应曲线并比较半数有效浓度（EC50），有可能表明当所有三个亚基cDNA都存在时，NR1 + NR2A + NR2C受体优先共同组装。该受体对甘氨酸的亲和力介于NR1 + NR2A和NR1 + NR2C之间，但希尔系数相似。因此，两种不同的NR2亚基可以在同一受体中结合，赋予独特的药理学特性，这表明很可能两个或更多NR2亚基在同一NMDA受体复合物中共同组装。
