Alterations of pituitary immunocytochemical and morphometric parameters in juvenile female rats following estradiol and hCG treatment

Immunocytochemical and morphometric changes of pituitary FSH and LH cells in juvenile (17th day of life) female rats neonatally (4th day of life) treated with five 0.25 mg doses of estradiol dipropionate (EDP) or human chorionic gonadotrophin (14th and 16th day of life) and with the combination of both were studied using rabbit antirat beta-follicle stimulating hormone (FSH) and beta-luteinising hormone (LH) sera and a peroxidase-antiperoxidase (PAP) immunohistochemical procedure. Morphometry and stereology were applied to evaluate the changes in FSH- and LH-producing cells, number and volume densities of the cells and the nuclei. In EDP-treated females significantly increased pituitary mass and the number of chromophobes and PRL cells were observed while all morphometric parameters of FSH/LH cells were decreased in comparison with the corresponding controls. This difference was much more prominent in FSH-beta- than in LH-beta cells. Treatment with hCG led to an increase in the number of FSH and LH cells, but it was much more pronounced in the latter cells. In the group receiving EDP and hCG in combination, the effect of EDP was predominant in FSH cells and that of hCG in LH cells.nul