老龄大鼠下丘脑及垂体促肾上腺皮质激素样和β－内啡肽样免疫阳性细胞的相关变化

正常Ｗｉｓｔａｒ大鼠，雌雄不拘，老龄鼠（２０个月）８只，壮龄鼠（８个月）１３只。石蜡切片，ＡＢＣ法染色，ＤＡＢ显色．光镜下观察下丘脑及垂体促肾上腺皮质激素样免疫反应（ＡＣＴＨ－ｉｒ）和β－内啡肽样免疫反应（β－ＥＮｒｙ－ｉｒ）阳性细胞的形态、分布和计数。图像分析仪测其灰度值、结果：下丘脑弓状核β－ＥＮＤ－ｉｒ阳性细胞可分为胞核不明显、着色较深、数量较多的强阳性细胞和胞核明显、着色较淡、数量较少的弱阳性细胞；ＡＣＴＨ－ｉｒ阳性细胞，胞核明显，胞体较大，类似于β－ＥＮＤ－ｉｒ弱阳性细胞。老龄大鼠这两种阳性细胞出现率均明显低于壮龄大鼠。弓状核和垂体前叶ＡＣＴＨ－ｉｒ阳性细胞灰度值老龄鼠显著低于壮龄鼠，而β－ＥＮＤ－ｉｒ阳性细胞灰度值老龄鼠则显著高于壮龄鼠。

THE CORRELATIVE CHANGES BETWEEN ACTH-IR AND β-ENDORPHIN-IR CELLS OF THE HYPOTHALAMUS AND PITUITARY IN THE AGED RATS

In order to research the correlative changes between ACTH and β-endorphin in the hypothalamus and pituitary ace observed ACTH-immunoreactive (ACTH-ir) and β-endorphin-immunoreactive (β-END-ir) cells of t he hypothalamus and pituitary in the rats. In this study, the normal female and male Wistar rats, 8 aged rats (twenty-month-old) and aha blocks containing hypothalamus were dehydrated and embebedded in paraffin (50～52℃). The sections (7μm) were stained with ABC immunolistochemical technigue and were coloured by DAB. The morphology, distribution and numbers of ACTH-ir and β-END-ir cells of the hypothalarnus and pituitary in the rats were observed and quantified under microscope. The light values of positive cells were measured with Image Analyser. The results had been showed that β-END-ir neurons in the arcuate nucleus may be divided into two types: (1) darkly coloured positive neurons, which contained dim nucleus or dark cytoplasm and were frequently seenl (2) lightly coloured positive neurons, which contained clear nucleus or light cytoplasm in colour and were rarely seen. The ACTH-ir neurons in the arcuate nucleus are similar to the second type of β-END-ir neurons. The numbers of ACTH-ir and β-END-ir neurons of the arcuate nucleus in the aged rats are lower than those in the adult rats (p<0.05). The light values of ACTH-ir cens of the arcuate nucleus and anterior lobe of pituitary in the aged rats are obviously lower than that in the adult rats (P<0.0001), but that of β-END-ir cells are opposite (P<0.0001).