Effects of Melatonin Levels on Neurotoxicity of the Medial Prefrontal Cortex in a Rat Model of Parkinson＇s Disease  

作　　者：Yan Li Shu-Mei Wang Lei Guo Jian Zhu Ying Wang Lei Li Yan-Xin Zhao 

机构地区：[1]Department of Neurology, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, China [2]General Medical Teaching and Research Section, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, China [3]Department of Medical Imaging, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, China [4]Department of Medical Imaging, Shandong Provincial Hospital, Jinan, Shandong 250014, China

出　　处：《Chinese Medical Journal》2017年第22期2726-2731,共6页中华医学杂志（英文版）

摘　　要：Background： Damage of the medial prefrontal cortex （mPFC） results in similar characteristics to the cognitive deficiency seen with the progress of Parkinson＇s disease （PD）. Since the course of mPFC damage is still unclear, our study aimed to investigate the effects of melatonin （MT） on neurotoxicity in the mPFC of a rat model of PD. Methods： One hundred and fifty-four normal, male Wistar rats were randomly divided into the following five groups： normal ＋ normal saline （NS）, normal ＋ 6-hydroxydopamine （6-OHDA）, sham pinealectomy （PX） ＋ 6-OHDA, PX ＋ 6-OHDA, and MT ＋ 6-OHDA. 6-OHDA was injected into the right substantia nigra pars compacta （SNc） and ventral tegmental area （VTA） of each group, except normal ＋ NS, 60 days after the PX. In the MT treatment group, MT was administered immediately after the intraperitoneal injection at 4 p.m. every day, for 14 days. Neuronal apoptosis in the mPFC was exalnined using the TUNEL method, while the expression oftyrosine hydroxylase （TH）, Bax, and Bcl-2 in this region was measured using immunohistochemistry. The concentration of malondialdehyde （MDA） in the mPFC was examined using the thioharbituric acid method. Results： Rats in the normal ＋ 6-OHDA and sham PX ＋ 6-OHDA groups were combined into one group （Group N ＋ 6-OHDA） since there was no significant discrepancy between the groups for all the detected parameters. Apoptosis of cells in the NS, MT ＋ 6-OHDA, N ＋ 6-OH DA, and PX ＋ 6-OHDA groups was successively significantly increased （Hc = 256.25, P 〈 0.001 ）. The gray value of TH （＋） fibers in the NS, MT ＋ 6-OHDA, N ＋ 6-OHDA, and PX ＋ 6-OHDA groups was also successively significantly increased （F= 99.33, P 〈 0.001 ）. The staining intensities of Bax and Bcl-2 were as follows： Group NS ＋/＋, Group MT ＋ 6-OHDA ＋＋/＋, Group N ＋ 6-OHDA ＋＋/＋, and PX ＋ 6-OHDA ＋＋＋/＋. The concentrations of MDA in the NS, MT ＋ 6-OHDA, N ＋ 6-OHDA, and PX ＋ 6-OHDA groupBackground： Damage of the medial prefrontal cortex （mPFC） results in similar characteristics to the cognitive deficiency seen with the progress of Parkinson＇s disease （PD）. Since the course of mPFC damage is still unclear, our study aimed to investigate the effects of melatonin （MT） on neurotoxicity in the mPFC of a rat model of PD. Methods： One hundred and fifty-four normal, male Wistar rats were randomly divided into the following five groups： normal ＋ normal saline （NS）, normal ＋ 6-hydroxydopamine （6-OHDA）, sham pinealectomy （PX） ＋ 6-OHDA, PX ＋ 6-OHDA, and MT ＋ 6-OHDA. 6-OHDA was injected into the right substantia nigra pars compacta （SNc） and ventral tegmental area （VTA） of each group, except normal ＋ NS, 60 days after the PX. In the MT treatment group, MT was administered immediately after the intraperitoneal injection at 4 p.m. every day, for 14 days. Neuronal apoptosis in the mPFC was exalnined using the TUNEL method, while the expression oftyrosine hydroxylase （TH）, Bax, and Bcl-2 in this region was measured using immunohistochemistry. The concentration of malondialdehyde （MDA） in the mPFC was examined using the thioharbituric acid method. Results： Rats in the normal ＋ 6-OHDA and sham PX ＋ 6-OHDA groups were combined into one group （Group N ＋ 6-OHDA） since there was no significant discrepancy between the groups for all the detected parameters. Apoptosis of cells in the NS, MT ＋ 6-OHDA, N ＋ 6-OH DA, and PX ＋ 6-OHDA groups was successively significantly increased （Hc = 256.25, P 〈 0.001 ）. The gray value of TH （＋） fibers in the NS, MT ＋ 6-OHDA, N ＋ 6-OHDA, and PX ＋ 6-OHDA groups was also successively significantly increased （F= 99.33, P 〈 0.001 ）. The staining intensities of Bax and Bcl-2 were as follows： Group NS ＋/＋, Group MT ＋ 6-OHDA ＋＋/＋, Group N ＋ 6-OHDA ＋＋/＋, and PX ＋ 6-OHDA ＋＋＋/＋. The concentrations of MDA in the NS, MT ＋ 6-OHDA, N ＋ 6-OHDA, and PX ＋ 6-OHDA group

关 键 词：Medial Prefrontal Cortex MELATONIN PINEALECTOMY Tyrosine Hydroxylase Ventral Tegmental Area 

分 类 号：R0[医药卫生]