Kuwahara Sachi, Kesuma Sari Dwi, Tsukamoto Yasuhiro, Tanaka Shin, Sasaki Fumihiko
Laboratory of Veterinary Anatomy, Graduate School of Agriculture and Biological Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
Brain Res. 2004 Oct 29;1025(1-2):113-22. doi: 10.1016/j.brainres.2004.08.012.
We have observed growth hormone-releasing hormone (GHRH)-immunoreactive (ir) neurons in the arcuate nucleus (ARC), somatostatin (SS)-ir neurons in the periventricular nucleus (PeN), and pituitary growth hormone (GH)-ir cells in female C57BL/6J mice at 2 months old (2 M), 4, 12 and 23 M, using immunocytochemical and morphometric methods. The number of GHRH-ir neurons decreased with age. The number of SS-ir neurons increased from 2 to 4 M, but decreased after 4 M. The volume of the anterior pituitary and the number of adenohypophysial parenchymal cells fell from 12 to 23 M. The proportion of GH-ir cells decreased significantly from 2 to 4 M and decreased in number from 12 to 23 M as well as in size from 2 to 4 M and from 12 to 23 M. Our results show that both GHRH-ir neurons and SS-ir neurons are fewer in old female mice, but the ratio of the number of SS-ir neurons to GHRH-ir neurons increases in old females. We suggest that the fall in the number and size of GH-ir cells in the pituitary gland with age may be involved in the increase in the ratio of the number of SS-ir neurons to GHRH-ir neurons in the hypothalamus in female mice, as well as in males.
我们采用免疫细胞化学和形态计量学方法，观察了2月龄（2M）、4月龄、12月龄和23月龄雌性C57BL/6J小鼠弓状核（ARC）中生长激素释放激素（GHRH）免疫反应性（ir）神经元、室周核（PeN）中生长抑素（SS）-ir神经元以及垂体生长激素（GH）-ir细胞。GHRH-ir神经元数量随年龄增长而减少。SS-ir神经元数量在2至4月龄时增加，但4月龄后减少。垂体前叶体积和腺垂体实质细胞数量在12至23月龄时下降。GH-ir细胞比例在2至4月龄时显著降低，数量在12至23月龄时减少，大小在2至4月龄以及12至23月龄时也减小。我们的结果表明，老年雌性小鼠中GHRH-ir神经元和SS-ir神经元均减少，但老年雌性小鼠中SS-ir神经元与GHRH-ir神经元数量之比增加。我们认为，垂体中GH-ir细胞数量和大小随年龄增长而下降，可能与雌性小鼠以及雄性小鼠下丘脑SS-ir神经元与GHRH-ir神经元数量之比增加有关。
