Versteeg D H, Van Heuven-Nolsen D, De Wied D
Life Sci. 1984 Apr 16;34(16):1549-54. doi: 10.1016/0024-3205(84)90609-x.
The non-opiate beta-endorphin fragment des-Tyr1-gamma-endorphin (DT gamma E) had a decreasing effect on K+-induced release of tritiated dopamine from nucleus accumbens slices in vitro, when tissue was used of rats which prior to decapitation were in a state of low arousal. When nucleus accumbens tissue was used of rats which were mildly stressed by exposure to a novel environment prior to decapitation, this effect was absent, while an enhancing effect of DT gamma E became evident on basal dopamine efflux. This latter effect resembled that of haloperidol, which dose-dependently enhanced basal dopamine efflux in vitro. Exposure of rats to ether vapor shortly before decapitation abolished both these in vitro effects of DT gamma E. The results are interpreted as indicating that the quality of the modulating effects of DT gamma E on dopamine release from dopaminergic neurons projecting to the nucleus accumbens is depending on the state of activity of these neurons, which, in its turn, is a reflection of the state of arousal of the rats.
非阿片类β-内啡肽片段去酪氨酸1-γ-内啡肽（DTγE）对体外伏隔核切片中钾离子诱导的氚化多巴胺释放有降低作用，当使用断头前处于低觉醒状态大鼠的组织时。当使用断头前暴露于新环境而受到轻度应激的大鼠的伏隔核组织时，这种作用不存在，而DTγE对基础多巴胺流出有增强作用变得明显。后一种作用类似于氟哌啶醇的作用，氟哌啶醇在体外剂量依赖性地增强基础多巴胺流出。断头前不久将大鼠暴露于乙醚蒸气中消除了DTγE的这两种体外作用。结果被解释为表明DTγE对投射到伏隔核的多巴胺能神经元释放多巴胺的调节作用的性质取决于这些神经元的活动状态，而这又反映了大鼠的觉醒状态。
