Liang N Y, Rutledge C O
Biochem Pharmacol. 1982 Mar 15;31(6):983-92. doi: 10.1016/0006-2952(82)90332-x.
Amphetamine-induced release of previously accumulated [3H]dopamine ([3H]DA) was compared to the release of [3H]DA produced by unlabelled DA and fenfluramine. Like unlabelled DA, amphetamine was more potent than fenfluramine in releasing [3H]DA in all tissue preparations (untreated, pargyline-treated, and pargyline- and reserpine-treated corpus striatal slices). In tissue treated with both reserpine and pargyline, benztropine greatly reduced the efflux of [3H]DA produced by amphetamine and unlabelled DA but had only a slight effect on fenfluramine-induced release of [3H]DA. In the same tissue preparation, Q10 values for the release of [3H]DA produced by 3 X 10(-7) M amphetamine (1.8) and 3 X 10(-6) M unlabelled DA (1.7) were similar to that for the spontaneous release of [3H]DA (1.7). However, when the concentrations of amphetamine and unlabelled DA were increased to 10(-4) M, the Q10 values for the release of [3H]DA were diminished at the lower temperatures. These results suggest that amphetamine may release [3H]DA by two mechanisms: (1) by accelerated exchange diffusion due to its use of the DA uptake carrier to enter into neurons (this would predominate at low concentrations of amphetamine), and (2) by passive entrance into neurons and displacement of [3H]DA from binding sites (this would predominate at high concentrations of amphetamine).
将苯丙胺诱导的先前积累的[3H]多巴胺（[3H]DA）释放与未标记的多巴胺和芬氟拉明产生的[3H]DA释放进行了比较。与未标记的多巴胺一样，在所有组织制剂（未处理、帕吉林处理、帕吉林和利血平处理的纹状体切片）中，苯丙胺在释放[3H]DA方面比芬氟拉明更有效。在用利血平和帕吉林处理的组织中，苯海索大大减少了苯丙胺和未标记的多巴胺产生的[3H]DA流出，但对芬氟拉明诱导的[3H]DA释放只有轻微影响。在相同的组织制剂中，3×10^(-7) M苯丙胺（1.8）和3×10^(-6) M未标记的多巴胺（1.7）产生的[3H]DA释放的Q10值与[3H]DA的自发释放（1.7）相似。然而，当苯丙胺和未标记的多巴胺浓度增加到10^(-4) M时，在较低温度下[3H]DA释放的Q10值降低。这些结果表明，苯丙胺可能通过两种机制释放[3H]DA：（1）通过利用多巴胺摄取载体进入神经元而加速交换扩散（在低浓度苯丙胺时占主导），以及（2）通过被动进入神经元并从结合位点置换[3H]DA（在高浓度苯丙胺时占主导）。
