Immunocytochemical observation of adenohypophysis in a human growth hormone (hGH) gene transgenic mouse

Abstract

Adenohypophysis was immunocytochemically examined in an infertile female transgenic (Tg) mouse which carried human growth hormone (hGH) gene and had a high circulating level of hGH. No GH positive cells were detected. This confirmed the extrahypophyseal (ectopic) production of hGH and was coincident with the disappearance of parenchymal cells showing affinity to azocarmine in Azan staining. The normal frequency of ACTH positive cells was in accordance with the previous suggestion based on the changes found in zona fasciculata cells of the adrenal cortex. Most interesting findings were the detection of many PRL positive cells and the ovarian histology with nearly normal characteristics except for the presence of thick capsule and interstitial gland-like structure composed of large and light cells. Ovarian histology was also clearly different among individual Tg mice, even though they stemmed from the same line or progenitors, and had a similar phenotype. The current immunocytochemical observation well documented the changes revealed with Azan staining in the adenohypophysis about GH but not about PRL or ACTH. Thus, the immunocytochemical analysis of the adenohypophysis will provide useful methodology in assessment of endocrinological circumstances of Tg mice.