Adjeroud S, Tonon M C, Gouteux L, Leneveu E, Lamacz M, Cazin L, Vaudry H
Gen Comp Endocrinol. 1986 Dec;64(3):428-34. doi: 10.1016/0016-6480(86)90079-1.
The interaction between dopamine and TRH on alpha-melanocyte-stimulating hormone (MSH) release from the intermediate lobe of amphibian pituitary has been studied in vitro using the perifusion model. Dopamine (10(-10) to 10(-6) M) was responsible for a dose-related inhibition of alpha-MSH secretion. The inhibitory effect of dopamine (10(-8) and 3.16 X 10(-8) M) was completely abolished in the presence of haloperidol (10(-5) and 10(-6) M, respectively). It has been previously established that, in amphibians, TRH stimulated alpha-MSH release in vitro and that the action of TRH was not mediated via an inhibition of the release of endogenous dopamine (M. C. Tonon, P. Leroux, M. E. Stoeckel, S. Jégou, G. Pelletier, and H. Vaudry, 1986, Endocrinology 112, 133-141). In the present study we demonstrate that TRH (10(-7) M) reverses the inhibitory effect of dopamine (for concentrations ranging from 3.16 X 10(-8) to 10(-6) M) on alpha-MSH secretion and that the effects of TRH and dopamine are additive. Thus, these results indicate that the intracellular events associated with TRH-induced stimulation and dopamine-induced inhibition of alpha-MSH release are not linked together.
利用灌流模型在体外研究了多巴胺与促甲状腺激素释放激素（TRH）对两栖类垂体中间叶α-促黑素细胞激素（α-MSH）释放的相互作用。多巴胺（10^(-10)至10^(-6) M）呈剂量依赖性抑制α-MSH分泌。在分别存在氟哌啶醇（10^(-5)和10^(-6) M）的情况下，多巴胺（10^(-8)和3.16×10^(-8) M）的抑制作用完全被消除。先前已经确定，在两栖类动物中，TRH在体外刺激α-MSH释放，且TRH的作用不是通过抑制内源性多巴胺的释放介导的（M.C.托农、P.勒鲁、M.E.斯托克尔、S.热古、G.佩尔捷和H.沃德里，1986年，《内分泌学》112卷，133 - 141页）。在本研究中，我们证明TRH（10^(-7) M）可逆转多巴胺（浓度范围为3.16×10^(-8)至10^(-6) M）对α-MSH分泌的抑制作用，且TRH和多巴胺的作用是相加的。因此，这些结果表明，与TRH诱导的刺激和多巴胺诱导的α-MSH释放抑制相关的细胞内事件没有联系在一起。
