多巴胺能系统对纹状体黑质通路中强啡肽A1-8浓度的调节。

Regulation of the concentration of dynorphin A1-8 in the striatonigral pathway by the dopaminergic system.

作者信息

Li S, Sivam S P, Hong J S

出版信息

Brain Res. 1986 Nov 29;398(2):390-2. doi: 10.1016/0006-8993(86)91502-7.

Abstract

The purpose of this study was to explore the dopaminergic control of the striatonigral dynorphin system by measuring the levels of dynorphin A1-8-like immunoreactivity (DN-LI) after repeated injections of a dopaminergic receptor agonist or antagonist. Seven daily injections of different doses of apomorphine (0.5, 1.0, 2.5 and 5.0 mg/kg, s.c.) caused a significant dose-related increase of DN-LI in the striatum (26, 34, 63, 85% over control at each corresponding dose). Similar increases were observed in the substantia nigra (22, 52, 50 and 62% over control). In another experiment, rats received 5 mg/kg of apomorphine for 1, 3, and 7 days. There was a significant time-related increase in DN-LI both in the striatum (37, 50 and 85% over control at each corresponding period) and in the substantial nigra (32, 78 and 62%). Repeated administration of haloperidol (1 mg/kg, i.p.) failed to change the striatal level of DN-LI, but, when given at the same time as apomorphine, significantly attenuated the effect of apomorphine. These results suggest that dopamine exerts a modulatory influence on the metabolism of dynorphin in the striatonigral pathway.

摘要

本研究的目的是通过测量重复注射多巴胺能受体激动剂或拮抗剂后强啡肽A1-8样免疫反应性（DN-LI）水平，来探索多巴胺能对纹状体黑质强啡肽系统的控制。连续7天每天注射不同剂量的阿扑吗啡（0.5、1.0、2.5和5.0mg/kg，皮下注射）导致纹状体中DN-LI呈显著剂量相关增加（各相应剂量下比对照组分别增加26%、34%、63%、85%）。在黑质中也观察到类似的增加（比对照组分别增加22%、52%、50%和62%）。在另一项实验中，大鼠接受5mg/kg阿扑吗啡注射1天、3天和7天。纹状体和黑质中DN-LI均出现显著的时间相关增加（各相应时间段比对照组分别增加37%、50%和85%以及32%、78%和62%）。重复给予氟哌啶醇（1mg/kg，腹腔注射）未能改变纹状体中DN-LI水平，但与阿扑吗啡同时给药时，能显著减弱阿扑吗啡的作用。这些结果表明，多巴胺对纹状体黑质通路中强啡肽的代谢发挥调节作用。