Disruption in the Expression and Immunolocalization of Steroid Receptors and Steroidogenic Enzymes in Letrozole-induced Polycystic Ovaries in Rat.

ZURVARRA FM; SALVETTI NR; IAN MASON J; VELAZQUEZ MML; ALFARO NS; ORTEGA HH

REPRODUCTION FERTILITY AND DEVELOPMENT

CSIRO PUBLISHING

Lugar: Melbourne; Año: 2009 vol. 21 p. 827 - 839

1031-3613

Our objective was to characterize the expression and tissular distribution of steroid receptors (ERa, ERb, AR and PR) and steroidogenic enzymes (P450arom, 3-b-HSD and StAR) in letrozole-induced polycystic ovaries of rats. Changes in serum hormone levels, protein expression in whole ovaries by western blot analysis and protein immunolocalization by immunohistochemistry were determined in female rats treated with the aromatase inhibitor letrozole and compared with controls in proestrous and diestrous. Increases in the serum LH, FSH and testosterone concentrations were observed in letrozole-treated rats while serum estradiol and progesterone levels were reducted. The protein expression analyzed western immunoblot was consistent with the immunohistochemical data. Letrozole treatment induced an increase in the expression of AR, StAR and 3b-HSD and a decrease in ER-a. ER-b, PR and P450arom showed partial changes in relation to some cycle stages. These results indicate that cystogenesis in this experimental model is characterized by changes in steroid receptors and steroidogenic enzyme expression that may be essential to proper ovarian functioning and are in agreement with similar changes observed in women with PCOS.