Apoptotic cell death of estrogen activated lactotrophs induced by tamoxifen

AOKI MP; ORGNERO E; AOKI A; MALDONADO CA

CHURCHILL LIVINGSTONE

Año: 2003 vol. 35 p. 143 - 143

timulation and inhibition of lactotroph cells cause remarkable morphological and functional changes. In keeping with these changes,the size of the lactotroph cell population undergoes striking alterations due to proliferation or cell death. Factors involved in the induction ofapoptosis of pituitary cells are not well established. We demonstrated earlier that oestrogens prevent lactotroph cells of female rats to die byapoptosis induced by bromocryptine treatment, a fact that can be reversed in ovariectomised rats. In this study, we developed experimentalmodels for in vivo and in vitro studies to gain further insight on the survival effect of oestrogens on lactotrophs. In rats pretreated withoestrogens, tamoxifen generates a massive cell death by apoptosis as validated by the TUNEL technique and DNA electrophoresis ofpituitary gland. On electron microscope observations, numerous lactotrophs exhibited progressive morphological changes in the nuclei