Chen N H, Xu C, Coffey L L, Reith M E
School of Basic Medical Sciences, Nanjing Medical University, People's Republic of China.
Biochem Pharmacol. 1996 Feb 23;51(4):563-6. doi: 10.1016/0006-2952(95)02208-2.
Potential differences between somatodendritic acid and axonal dopamine transporters were examined by comparing the binding constants of [3H]WIN 35, 428 [2 beta-carbomethoxy- 3 beta-(4-fluorophenyl)tropane] binding to membranes prepared from the rat ventral mesencephalon, containing A9 and A10 dopamine cell bodies, and from the nucleus accumbens. Saturation analysis of [3H]WIN 35,428 binding, in the presence of compounds to occlude norepinephrine and serotonin transporters, was performed by both the "unlabeled" method (varying unlabeled ligand) and "labeled" method (varying radioligand). The density of binding was substantially lower in the ventral mesencephalon than in the nucleus accumbens, but the binding affinity was only slightly different. Likewise, the differences between the two regions in the inhibitory potency of cocaine and GBR 12909 [1-(2-di(4-fluorophenyl)-methoxy-ethyl)4-(3-phenylpropyl)piperazine] were not substantial. The results suggest that somatodendritic and axonal dopamine transporters in the ventral mesencephalon and nucleus accumbens are not very different as far as their binding domains for uptake blockers such as cocaine and GBR 12909 are concerned.
通过比较[3H]WIN 35,428[2β-甲氧基羰基-3β-(4-氟苯基)托烷]与从含有A9和A10多巴胺细胞体的大鼠腹侧中脑制备的膜以及伏隔核制备的膜的结合常数，研究了树突体酸和轴突多巴胺转运体之间的潜在差异。在存在用于封闭去甲肾上腺素和5-羟色胺转运体的化合物的情况下，通过“未标记”方法（改变未标记配体）和“标记”方法（改变放射性配体）对[3H]WIN 35,428结合进行饱和分析。腹侧中脑的结合密度明显低于伏隔核，但结合亲和力仅有轻微差异。同样，可卡因和GBR 12909[1-(2-二(4-氟苯基)-甲氧基-乙基)4-(3-苯基丙基)哌嗪]的抑制效力在两个区域之间的差异也不显著。结果表明，就可卡因和GBR 12909等摄取阻滞剂的结合结构域而言，腹侧中脑和伏隔核中的树突体和轴突多巴胺转运体并没有很大差异。
