TY - JOUR A1 - , T1 - Apoptosis is involved in the anti-proliferative effect of corticosteroid in non-tumoral ACTH pituitary cells JO - Eur. J. Anat. SN - 1136-4890 Y1 - 2006 VL - 10 SP - 143 EP - 149 UR - http://www.eurjanat.com/web/paper.php?id=06030143 KW - corticosterone KW - corticotropin KW - adrenalectomy KW - animal experiment KW - animal model KW - animal tissue KW - apoptosis KW - article KW - cell proliferation KW - controlled study KW - corticotropin release KW - drug effect KW - drug inhibition KW - electrosurgery KW - hypophysis cell KW - immunohistochemistry KW - negative feedback KW - nonhuman KW - rat N2 - Glucocorticoids are the physiological negative feedback on ACTH secretion and may be involved in regulating the maintenance of the population of hypophyseal ACTH-cells, because following surgical ablation, adrenalectomy induces an increase in the number of these cells in the early stages. Glucocorticoids have been implicated in the induction of apoptosis in several tissues; but they have been little considered as hormonal inducers of apoptosis in the pituitary gland. By means of a double immunohistochemical study for PCNA and ACTH and a double assay by ISEL and immunohistochemistry for ACTH, the aim of the present study was to analyse whether corticosterone induces apoptosis and inhibits cellular proliferation to control non-tumoral ACTH-cells in the pituitary gland. For this purpose untreated, sham-operated and adrenalectomized rats, treated or not with corticosterone, were compared. The results of the present study demonstrate a very important decrease in proliferation and an increase in apoptosis of pituitary ACTH-positive cells induced by corticosterone, suggesting that the number of pituitary ACTH-producing cells is mainly controlled by glucocorticoids by means of cellular proliferation and apoptosis. ER -