title: Disruption in the expression and immunolocalisation of steroid receptors and steroidogenic enzymes in letrozole-induced polycystic ovaries in rat.
abstract: The objective of the present study was to characterise the expression and tissue distribution of steroid receptors (oestrogen receptor-alpha and -beta (ERalpha, ERbeta), androgen receptor (AR) and progesterone receptor (PR)) and steroidogenic enzymes (P450 aromatase (P450arom), 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and steroidogenic acute regulatory protein (StAR)) in letrozole-induced polycystic ovaries of rats. Changes in serum hormone levels, protein expression in whole ovaries by western blot analysis and protein localisation by immunohistochemistry were determined in female rats treated with the aromatase inhibitor letrozole and compared with controls in proestrous and diestrous rats. Increases in the serum LH, FSH and testosterone concentrations were observed in letrozole-treated rats whereas serum oestradiol and progesterone levels were reduced. Protein expression as analysed by western immunoblot was consistent with the immunohistochemical data. Letrozole treatment induced an increase in the expression of AR, StAR and 3beta-HSD and a decrease in ERbeta. ERalpha, PR and P450arom showed partial changes in relation to some cycle stages. These results indicate that cystogenesis in this experimental model is characterised 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.
authors.affiliation: Department of Morphological Sciences and Center for Experimental Biology and Laboratory Animals Sciences, Faculty of Veterinary Sciences, Universidad Nacional del Litoral, Argentina.
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Zurvarra
authors.forename: Natalia R
authors.initials: NR
authors.lastname: Salvetti
authors.forename: J Ian
authors.initials: JI
authors.lastname: Mason
authors.forename: Melisa M L
authors.initials: MM
authors.lastname: Velazquez
authors.forename: Natalia S
authors.initials: NS
authors.lastname: Alfaro
authors.forename: Hugo H
authors.initials: HH
authors.lastname: Ortega
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000818:Animals; D001141:Aromatase / Q000378:metabolism*; D015153:Blotting, Western; D004031:Diestrus; D004195:Disease Models, Animal; D004958:Estradiol / Q000097:blood; D047628:Estrogen Receptor alpha / Q000378:metabolism; D047629:Estrogen Receptor beta / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D007150:Immunohistochemistry; D000077289:Letrozole; D007986:Luteinizing Hormone / Q000097:blood; D009570:Nitriles; D010053:Ovary / Q000201:enzymology* / Q000503:physiopathology; D010750:Phosphoproteins / Q000378:metabolism*; D011085:Polycystic Ovary Syndrome / Q000139:chemically induced / Q000201:enzymology* / Q000503:physiopathology; D011359:Proestrus; D011374:Progesterone / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D011944:Receptors, Androgen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D011987:Receptors, Steroid / Q000378:metabolism*; D013739:Testosterone / Q000097:blood; D014230:Triazoles; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D009570:Nitriles; D010750:Phosphoproteins; D011944:Receptors, Androgen; D011980:Receptors, Progesterone; D011987:Receptors, Steroid; D014230:Triazoles; D000098682:Steroidogenic Acute Regulatory Protein; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D000077289:Letrozole; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D015096:3-Hydroxysteroid Dehydrogenases; D001141:Aromatase