Andersen S L, Umphress S M, Robinson S R, Smotherman W P, Ward K M, Kehoe P
Department of Psychology, State University of New York at Binghamton 13902-6000.
Pharmacol Biochem Behav. 1993 Oct;46(2):377-81. doi: 10.1016/0091-3057(93)90367-3.
Presentation of milk to the newborn rat promotes changes in sensory and motor behavior and concomitant changes in both endogenous opioid and dopamine systems. The present study employed an in vivo binding technique with a tritiated ligand for the D2 receptor ([3H]raclopride) to examine the effects of intraoral milk infusion and opioid manipulations on dopamine activity in the term rat fetus (E21). In Experiment 1, fetuses received a series of milk infusion, which resulted in decreased occupancy at D2 receptors by the endogenous ligand, dopamine, in striatal, septal, and hypothalamic brain regions. In Experiment 2, fetuses were pretreated with morphine, the mu-agonist [D-Ala2,NMe-Phe4,Gly5-ol]-enkephalin (DAMGO), the kappa-agonist U50,488, or saline. Opioid manipulations had no effect on binding at D2 receptors. These results confirm that intraoral milk infusion can modulate activity in the dopamine system of the near-term fetal rat.
给新生大鼠喂奶会促进其感觉和运动行为的变化，同时内源性阿片系统和多巴胺系统也会发生相应变化。本研究采用一种体内结合技术，使用针对D2受体的氚标记配体（[3H]雷氯必利），来检测经口输注牛奶和阿片类药物处理对足月大鼠胎儿（E21）多巴胺活性的影响。在实验1中，胎儿接受了一系列牛奶输注，这导致纹状体、隔区和下丘脑脑区中内源性配体多巴胺对D2受体的占有率降低。在实验2中，胎儿分别用吗啡、μ激动剂[D-Ala2，NMe-Phe4，Gly5-ol]-脑啡肽（DAMGO）、κ激动剂U50,488或生理盐水进行预处理。阿片类药物处理对D2受体的结合没有影响。这些结果证实，经口输注牛奶可以调节近足月胎儿大鼠多巴胺系统的活性。
