摘要
目的： 观察模拟失重大鼠在硝普钠诱发瞬间低血压后延髓内脏带儿茶酚胺能神经元的Ｆｏｓ表达． 方法： 用尾部悬吊大鼠４ ｗ ｋ 模拟失重，静脉注射硝普钠制作低血压模型，用抗Ｆｏｓ蛋白和抗酪氨酸羟化酶（ＴＨ）的双重免疫组织化学方法（ＡＢＣ法），观察延髓内脏带内Ｆｏｓ 蛋白表达及其与ＴＨ阳性神经元的共存． 结果： 在低血压处理后，有相当数量的Ｆｏｓ阳性细胞出现在延髓内，它们主要局限在延髓内脏带内，并以孤束核与延髓腹外侧区较为密集． 但与单纯模拟失重和单纯给药大鼠比较，Ｆｏｓ阳性细胞数和腹外侧区Ｆｏｓ／ＴＨ 双标细胞占ＴＨ阳性细胞的比例明显减少，且ＴＨ神经元免疫反应减弱． 结论： 延髓内脏带内对瞬间血压下降起反应神经元（Ｆｏｓ阳性细胞）数量的下降以及儿茶酚胺能神经元表达Ｆｏｓ的降低，可能与模拟失重大鼠交感系统功能的减弱有关．
AIM: To observe Fos expression induced by transient decrease of blood pressure in catecholaminergic neurons of the medullary visceral zone in simulated weightlessness rats. METHODS: Simulated weightlessness was created by tail suspension for 4 weeks, and transient decrease of blood pressure was induced by intravenous injection of sodium nitroferricyanide. Fos expression in catechlaminergic neurons was observed by a double immunohistochemical staining with anti Fos and anti tyrosine hydroxylase (TH) antibodies. RESULTS: The decrease of blood pressure in the simulated weightlessness rats resulted in Fos expression in many neurons of the medulla oblongata, which were primarily localized in the medullary visceral zone. In the medullary visceral zone, Fos positive neurons were concentrated in the nucleus of the solitary tract and ventrolateral region of the medulla. But the number of Fos positive neurons in the medullary visceral zone was less numerous than that of the control rats (treated with tail suspension or intravenous injection of sodium nitroferricyanide only). Although some TH positive neurons were found to be Fos positive, the proportion of TH/Fos double labeled neurons was much lower than that of the control rats. The intensity of TH like immunoreactivity was also reduced. CONCLUSION: The decrease of Fos positive neurons and the proportion of catechlaminergic neurons expressing Fos protein may result from the decrease of parasympathetic activity in the simulated weightlessness rats.
出处
《第四军医大学学报》
1999年第10期855-859,共5页
Journal of the Fourth Military Medical University
关键词
延髓内脏带
失重模拟
心血管调节
FOS基因
medullary visceral zone
weightlessness simulation
cardiovascular modulation
genes Fos
immunohistochemistry
rat
