Liu Qiaofeng, Li Yanxia, Liu Yang, Zhao Yanshuang, Li Xuemei, Zhang Yiping, Wang Chenyi, Huang Wenli, Wang Xin
a Department of Pathology and Pathophysiology , Basic Medical College, Chengdu Medical College , Chengdu , China.
b School of Pharmacy , Chengdu Medical College , Chengdu , China.
Neurol Res. 2018 Dec;40(12):1080-1087. doi: 10.1080/01616412.2018.1519946. Epub 2018 Sep 17.
The objective of this article is to study the role of the dopamine (DA) D1 receptor in the midbrain periaqueductal grey (PAG) on learning and memory in morphine-addicted rats.
DA D1 receptor agonist SKF81297 and D1 receptor antagonist SCH SCH23390 were administrated into the PAG, respectively, and the learning and memory behavioral changes of morphine addicted rats were detected by water maze. Western blot and immunohistochemistry were used to detect glutamate decarboxylase 67 (GAD67) and tyrosine receptor kinase B (TrkB) in PAG.
D1 receptor agonist shortened the latency to platform and increased the number of platform crossings, indicating improved learning and memory ability of morphine addict rat. D1 receptor agonist increased GAD67 expression and decreased TrkB in PAG.
(1) The PAG is involved in the learning and memory changes of the addicted rats; (2) the activation of DA D1 receptor will increase the GAD67, reduce the damage to peripheral neurons, and improve the learning and memory of the addicted rats; and (3) D1 receptor agonists further reduced TrkB expression in morphine-addicted rats, whereas TrkB levels deviated from changes in rat behavior.
本文旨在研究中脑导水管周围灰质（PAG）中多巴胺（DA）D1受体在吗啡成瘾大鼠学习记忆中的作用。
分别向PAG中注射DA D1受体激动剂SKF81297和D1受体拮抗剂SCH23390，采用水迷宫检测吗啡成瘾大鼠学习记忆行为变化。采用蛋白质免疫印迹法（Western blot）和免疫组织化学法检测PAG中谷氨酸脱羧酶67（GAD67）和酪氨酸受体激酶B（TrkB）。
D1受体激动剂缩短了到达平台的潜伏期，增加了穿越平台的次数，表明吗啡成瘾大鼠学习记忆能力得到改善。D1受体激动剂增加了PAG中GAD67的表达，降低了TrkB的表达。
（1）PAG参与成瘾大鼠的学习记忆改变；（2）DA D1受体激活可增加GAD67表达，减轻对周围神经元的损伤，改善成瘾大鼠的学习记忆；（3）D1受体激动剂进一步降低吗啡成瘾大鼠TrkB表达，而TrkB水平与大鼠行为变化不一致。
