【摘要】 目的:观察外源性给予褪黑素对大鼠下丘脑弓状核内神经细胞的前阿黑皮素（POMC） mRNA表达水平的影响。方法:实验大鼠分给药组及对照组,给药组大鼠间隔12 h腹腔注射褪黑素2次（9∶00 am,9∶00pm）,每次剂量90mg·kg^-1,对照组大鼠注射配药液。最后一次注射后12 h,灌注取脑、冰冻切片,进行原位杂交实验,计算机图像处理技术测定染色脑片积分光密度（IOD）值、平均光密度（OD）值。结果:给药组大鼠下丘脑弓状核内POMC mRNA表达明显增强;其IOD和OD值均显著增加。结论:褪黑素可加强大鼠弓状核内POMC mRNA的表达。更多还原

【Abstract】 AIM: To observe altered expression of pro-opiome-lanocortin (POMC) mRNA localized in neurons in the arcuate nucleus of rat hypothalamus following exogenous administration of melatonin. METHODS: The experimental animals were divided into two groups injected ip with melatonin 90 mg·kg-1 and vehicle at 12 h interval (9:00 am and 9:00 pm). Twelve hours after, the last injection, the rat brains were processed for coronal sections and nonradioactive in situ hybridization histochem-istry technic was used. The integral optical density (IOD) and mean optical density (OD) of the stained brain sections were measured using the computer-assisted image processing technique. RESULTS: The POMC mRNA expression in the arcuate nucleus showed obvious enhancement in the brain sections of rats treated with melatonin. The IOD and OD values in the hypothalamic arcuate nucleus area were increased significantly (P < 0.01, P <0.05 respectively) with melatonin treatment. CONCLUSION: Melatonin may enhance the POMC mRNA expression in the arcuate nucleus of rat hypothalamus.更多还原