6-羟多巴损伤黑质导致弓状核离子钙接头蛋白1和阿片-促黑素皮质素原表达的变化

目的:观察6-羟多巴(6-OHDA)损伤大鼠黑质(SN)后下丘脑弓状核(Arc)中酪氨酸羟化酶(TH)、离子钙接头蛋白1(Iba1)和阿片-促黑素皮质素原(POMC)的表达变化,为帕金森病(PD)患者消瘦的发生机制提供线索。方法:20只SD大鼠随机分为6-OHDA大鼠组(双侧SN内注射6-OHDA)和对照组(注射等体积生理盐水)。免疫荧光染色和Western blot检测SN内TH,以及Arc内TH、Iba1和POMC的表达。结果:与对照组比较,6-OHDA大鼠组体重无明显变化,但腹膜后脂肪重量从(7.550±0.670)g减少到(3.895±0.465)g(P0.01)。SN内TH阳性细胞数量从56±5减少至14±2(P0.05);蛋白表达水平从0.75±0.11降低至0.41±0.09(P0.01)。Arc中TH阳性细胞数量从21±2减少到10±3(P0.05);Iba1阳性细胞数量从12±2增加到30±5(P0.05);POMC阳性细胞数量从16±4增加到31±2(P0.05)。下丘脑内TH蛋白的表达水平从0.35±0.05降低到0.21±0.02(P0.01);Iba1蛋白的表达水平从0.23±0.06增加至0.51±0.04(P0.01);POMC的蛋白表达水平从0.37±0.05增加至0.65±0.03(P0.01)。结论:Arc中TH、Iba1和POMC表达变化可能与PD脂肪减少存在一定的联系。

Changes of ionized calcium binding adapter molecule 1 and pro-opiome-lanocortin expression in arcuate nucleus of hypothalamus induced by substantia nigra lesion with 6-hydroxydopamine

AIM: To observe the expression of tyrosine hydroxylase (TH), ionized calcium binding adapter molecule 1 (Iba1) and pro-opiomelanocortin (POMC) in rat arcuate nucleus (Arc) of hypothalamus induced by substantia nigra (SN) lesion with 6-hydroxydopamine (6-OHDA).METHODS: According to the random number table, 20 SD rats were randomly divided into 6-OHDA group and control group. 6-OHDA was injected into the bilateral SN of the rats in 6-OHDA group, and the same volume of saline was injected into the same position of the rats in control group. After 6 weeks, the rats were sacrificed and the brains were obtained. Immunofluorescence staining and Western blot were used to detect TH expression in the SN, and TH, Iba1 and POMC expression in the Arc.RESULTS: Compared with control group, no significant change of body weight in 6-OHDA group was observed, but the weight of retroperitoneal fat decreased from (7.550±0.670) g to (3.895±0.465) g (P<0.01). The number of TH immunoreactive neurons in SN decreased from 56±5 to 14±2 (P<0.05), and the TH protein level decreased from 0.75±0.11 to 0.41±0.09 (P<0.01). In the Arc, the number of TH immunoreactive neurons decreased from 21±2 to 10±3 (P<0.05), the number of Iba1 immunoreactive neurons increased from 12±2 to 30±5 (P<0.05), and the number of POMC immunoreactive neurons increased from 16±4 to 31±2 (P<0.05). In the hypothalamus, the TH protein level decreased from 0.35±0.05 to 0.21±0.02 (P<0.01), the Iba1 protein level increased from 0.23±0.06 to 0.51±0.04 (P<0.01), and the POMC protein level increased from 0.37±0.05 to 0.65±0.03 (P<0.01).CONCLUSION: The changes of TH, Iba1 and POMC expression in Arc of 6-OHDA-treated rats may involved in the fat loss in Parkinson's disease.