烫伤对大鼠下丘脑视上核内皮素-1

烫伤对大鼠下丘脑视上核内皮素-1
基因转录和蛋白含量的影响

蒋应明　袁文俊　向正华　缪为民　林丽　李玲　焦炳华

摘　要: 　用原位杂交和免疫组织化学方法观察了烫伤后下丘脑视上核(SON)内皮素-1(ET-1)基因转录和蛋白含量的变化, 并用通用图像颗粒分析法估计ET-1 mRNA阳性杂交信号的强度和ET-1样免疫反应物(ET-1-ir)的免疫反应强度。与对照组相比, 烫伤后15 min, SON神经元胞浆内ET-1 mRNA阳性杂交信号未见明显变化; 而在烫伤后60和180 min, ET-1 mRNA阳性杂交信号强度分别较比照组增加35.1% (P<0.05)和62.4% (P<0.01)。在烫伤后15 min, SON神经元胞浆内ET-1-ir明显减少, 仅为对照组的8.5%, 显著低于对照组(P<0.01)。烫伤后60和180 min免疫反应物强度较烫伤后15 min有所回升, 分别为对照组的31.5%和52.4%, 但仍显著低于对照组(P<0.01)。用Northern法检测烫伤后下丘脑ET-1 mRNA含量和长度变化。结果显示, 在烫伤后15 min, ET-1 mRNA含量变化不显著, 在烫伤后60 min显著增多(P<0.05), 在烫伤后180 min继续增至对照组2.5倍, 但ET-1 mRNA长度在烫伤前后并无改变。以上结果表明, 烫伤后大鼠下丘脑SON ET-1 mRNA含量增加, 而ET-1-ir含量在烫伤后180 min内维持在低水平。鉴于SON具有神经内分泌作用, 烫伤后SON内ET-1 mRNA和ET-1-ir的变化提示，　ET-1在烫伤后的病理生理变化中可能有重要的神经内分泌作用。
关键词: 内皮素-1 mRNA; 内皮素-1; 烫伤; 下丘脑视上核
学科分类号: Q426; R363

Effect of scald on gene transcription and content of endothelin-1in supraoptic nucleus of rat hypothalamus

JIANG Ying-Ming　YUAN Wen-Jun　XIANG Zheng-Hua, 　MIAO Wei-Min, 　
LIN Li, 　LI Ling, 　JIAO Bing-Hua
(Department of Physiology, Second Military Medical University, Shanghai 200433)

Abstract: 　 Endothelin-1 (ET-1) gene transcription and endothelin-1-immunoreactivity (ET-1-ir) in the supraoptic nucleus (SON) of rat hypothalamus were respectively observed by in situ hybridization and immunohistochemistry after scald. Intensity of ET-1 mRNA and endothelin-1-immunoreactivity (ET-1-ir) was quantified by image analysis. Compared with the control (sham scald) group, no significant change in the intensity of ET-1 mRNA positive hybridization signals in SON was found 15 min post-scald, while there was a 35.1% increase in the positive hybridization signal intensity 60 min post-scald (P<0.05) and a 62.4% increase 180 min post-scald (P<0.01). The content of ET-1-ir in SON decreased significantly to 8.5% of the control 15 min post-scald (P<0.01), and gradually recovered to 31.5% and 52.4% of the control 60 min and 180 min post-scald respectively, though still significantly lower than the control (P<0.01). Pre- and post-scald ET-1 gene transcription in rat hypothalamus was also measured by Northern blot hybridization. No significant difference in the quantity of ET-1 mRNA was found between 15 min post-scald data and those of the control. The quantity increased to a significantly higher level 60 min post-scald (P<0.05) and further in-creased to 2.5 fold of the control 180 min post-scald (P<0.05). 　In addition, the Northern blot hybridiza-tion showed that the post-scald size of ET-1 mRNA remained unchanged despite of the increase in quantity. In view of the neuroendocrine role of SON, the changes in ET-1 mRNA and ET-1-ir in SON resulting from scald suggest that ET-1 may play an important role in neuroendocrine reactions following scald.
Key words: endothelin-1 mRNA; endothelin-1; scald; supraoptic nucleus of hypothalamus

Supported by the National Natural Science Foundation of China (No.39670243, No.39770855) and the Research Foundation for Medical Sciences of CPLA (the 9th Five-Year Program, No.96M072)

Corresponding author. Tel: 021-25070262; E-mail: yuanwj@smmu.edu.cn
Present address: Department of Hygieology and Toxicology, Second Military Medical University, Shanghai 200433

蒋应明（第二军医大学生理学教研室, 上海 200433）
袁文俊（第二军医大学生理学教研室, 上海 200433）
向正华（第二军医大学生理学教研室, 上海 200433）
缪为民（第二军医大学生理学教研室, 上海 200433）
林丽（第二军医大学生理学教研室, 上海 200433）
李玲（第二军医大学生理学教研室, 上海 200433）
焦炳华（第二军医大学生理学教研室, 上海 200433）

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　　Received 2000-01-04　　Accepted 2000-04-20