中文摘要：

目的探讨应激性胃溃疡大鼠前爪手掌不同区域黑色素变化及其机制。方法 采用随机数字表法将20只SD雄性大鼠分为空白对照组、模型组,每组各10只,利用无水乙醇灌胃复制应激性胃溃疡模型后,利用多巴氧化酶检测两组大鼠前爪皮肤黑色素变化;用ELISA法检测两组大鼠血清ghrelin水平;用RT-PCR法检测两组大鼠胃黏膜组织ghrelin mRNA、垂体和前爪皮肤组织POMC mRNA水平。结果 模型组大鼠5区的黑色素细胞明显增多;与空白对照大鼠比较,模型组大鼠的血清ghrelin水平及ghrelin mRNA降低,且差异有统计学差异（P〈0.05）;模型组大鼠的垂体和前爪皮肤组织POMC mRNA水平显著高于空白对照组（P〈0.05）。结论 应激性胃溃疡大鼠的病理变化可以在手掌特定区域通过黑色素的变化反映出来,初步推测其内在机制可能是通过作用于ghrelin-POMC通路实现的。

英文摘要：

Objective To investigate the change and the mechanism of melanin in forepaw skin of rats with irritable ulcer. Methods 20 rats were divided into two groups by random number table： blank control group and model group, each group had 10 rats. Acute gastric mucosal injury model was established by intragastric administration of 75% ethanol. The melanin levels of forepaw skin in the two groups were detected by dopa oxidase. Serum ghrelin levels in the two groups were detected by ELISA method. Ghrelin mRNA of Gastric mucous tissue, POMC mRNA of pituitary and forepaw skin tissues were detected by RT-PCR method. Results The melanin in J-zone were significantly in- creased in the model group. Compared with the blank control group, the ghrelin level and ghrelin mRNA in the model group significantly decreased （P 〈 0.05）. The POMC mRNA levels in the pituitary and forepaw skin tissues of the mod- el group were significantly higher than those in the blank control group （P 〈 0.05）. Conclusion The pathological changes of rats with irritable ulcer can be reflected by melanin in particular area of forepaw, preliminary speculation that the internal mechanism may be realized by ghrelin-POMC pathway.