Knoth J, Zallakian M, Njus D
Biochemistry. 1981 Nov 10;20(23):6625-9. doi: 10.1021/bi00526a016.
A proton-translocating adenosinetriphosphatase in adrenal medullary chromaffin granule ghosts can generate either a membrane potential (inside positive) or a pH gradient (inside acid). Dopamine uptake occurs in response to both the membrane potential and the pH gradient. The natural logarithm of the dopamine concentration gradient [In (Din/Dout)] is linearly related to the membrane potential with a slope of F/(RT). This dependence is not affected by the pH of the medium. In (Din/Dout) is linearly dependent on In ([H+]in/[H+]out) with a slope of 2. These results indicate that dopamine is taken up via an exchange diffusion or antiport mechanism. The stoichiometry of this exchange is two H+/dopamine cation and is independent of pH.
肾上腺髓质嗜铬粒蛋白颗粒膜泡中的质子转运三磷酸腺苷酶可产生膜电位（内正外负）或pH梯度（内酸外碱）。多巴胺的摄取对膜电位和pH梯度均有响应。多巴胺浓度梯度的自然对数[In (Din/Dout)]与膜电位呈线性关系，斜率为F/(RT)。这种依赖性不受介质pH的影响。In (Din/Dout)与In ([H+]in/[H+]out)呈线性相关，斜率为2。这些结果表明，多巴胺是通过交换扩散或反向转运机制摄取的。这种交换的化学计量比为两个H+/多巴胺阳离子，且与pH无关。
