Age-related changes in growth hormone (GH)-releasing hormone and somatostatin neurons in the hypothalamus and in GH cells in the anterior pituitary of female mice.
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.
Laboratory of Veterinary Anatomy, Graduate School of Agriculture and Biological Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
Sachi
S
Kuwahara
Dwi
D
Kesuma Sari
Yasuhiro
Y
Tsukamoto
Shin
S
Tanaka
Fumihiko
F
Sasaki
D000375:Aging / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D048429:Cell Size; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000032:analysis / Q000378:metabolism*; D007031:Hypothalamus / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D010903:Pituitary Gland, Anterior / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D013004:Somatostatin / Q000032:analysis / Q000378:metabolism*
D013004:Somatostatin; D013007:Growth Hormone-Releasing Hormone