注意缺陷多动障碍大鼠模型纹状体神经递质受体的表达

Expressions of catecholaminergic transmitter receptors in the striatum of spontaneous hypertension rats with attention deficit hyperactivity disorder

目的目前,儿童注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)的发病机制尚不清楚。文中探讨ADHD动物模型自发性高血压大鼠(spontaneous hypertensive rat,SHR)纹状体多巴胺D1受体(D1R)、D2受体(D2R)、酪氨酸羟化酶(TH)和5-羟色氨酸受体(5-HT2C)的表达变化。方法利用开场实验验证SHR模型的行为学表现,并采用免疫组化检测SHR和对照组大鼠的脑纹状体的相应蛋白表达。结果与对照组相比,SHR表现出明显的多动特征,且纹状体5-HT2C受体表达显著下调,甚至无表达,而D1R表达显著上调,D2R无明显变化,儿茶酚胺合成的限速酶TH无明显变化。结论SHR表现多动的特点由其神经生物学特点决定。纹状体高表达的D1R和低表达的5-HT2C一定程度上可揭示ADHD的病理、生理改变。

Objective Attention deficit hyperactivity disorder （ADHD） seriously affects the life and study of children and adolescents, and its pathogenic mechanism remains unknown. The purpose of this study was to explore the expressions of dopamine receptors （ D1 R and D2R） and 5-HT2C, and the rate-limiting enzyme for catecholamine biosynthesis （ tyrosine hydroxylase, TH） in the striatum of spontaneous hypertension （SH） rats. Methods The behaviors of 10 SH rats were assessed by open field test, and the protein expressions in the striatum of the rats were analyzed by immunohistochemistry in comparison with 10 WKY controls. Results Compared with the controls, the SH rats displayed significant hyperactivity, markedly elevated D1R expression and decreased 5-HT2C in the striatum, but no evident changes in D2R and TH expression. Conclusion ADHD in the SH rats was determined by their neurobiological characteristics. The high level of D1R and low level of 5-HT2C expression could partially ex-plain the pathophysiological change of ADHD.