Hu X J, Ticku M K
Department of Pharmacology, University of Texas, San Antonio.
Brain Res Dev Brain Res. 1994 Jul 15;80(1-2):137-40. doi: 10.1016/0165-3806(94)90097-3.
The development pattern of the GABAA/benzodiazepine (BZ) receptor ionophore complex was characterized in mammalian cortical cultured neurons utilizing radioligand binding and GABA-induced 36Cl-influx. The specific binding of [3H]flunitrazepam, [3H]Ro15-1788 and [3H]Ro15-4513 increased with time from day 3 to day 21. The EC50 value and Emax of the GABA, muscimol and pentobarbital to enhance [3H]-flunitrazepam binding did not change during the development. Furthermore, GABA-induced 36Cl- influx also did not change during development from day 3 to day 21. However, the potency of ligands that bind to type-1 BZ receptors (alprazolam, zolpidem and C1218,872) to inhibit [3H]flunitrazepam binding increased from day 7 to day 21. Taken together, these data suggest the presence of type-II BZ receptors in early stages of the development which appears to change to type-I BZ receptors with age in the cortical neurons in culture.
利用放射性配体结合和GABA诱导的36Cl内流，对哺乳动物皮层培养神经元中GABAA/苯二氮䓬（BZ）受体离子通道复合物的发育模式进行了表征。从第3天到第21天，[3H]氟硝西泮、[3H]Ro15 - 1788和[3H]Ro15 - 4513的特异性结合随时间增加。在发育过程中，GABA、蝇蕈醇和戊巴比妥增强[3H] - 氟硝西泮结合的EC50值和Emax没有变化。此外，从第3天到第21天的发育过程中，GABA诱导的36Cl内流也没有变化。然而，与1型BZ受体结合的配体（阿普唑仑、唑吡坦和C1218,872）抑制[3H]氟硝西泮结合的效力从第7天到第21天增加。综上所述，这些数据表明在发育早期存在II型BZ受体，在培养的皮层神经元中，其似乎随年龄增长转变为I型BZ受体。
