Brain sexual differentiation is a complex developmental phenomenon influenced by the genetic background, sex hormone secretions and environmental inputs, including pollution. The main hormonal drive to masculinize and defeminize the rodent brain is testosterone secreted by the testis. The hormone does not influence sex brain differentiation only in its native configuration, but it mostly needs local conversion into active metabolites (estradiol and DHT) through the action of specific enzymatic systems: the aromatase and 5alpha-reductase (5alpha-R), respectively. This allows the hormone to control target cell gene expression either through the estrogen (ER) or the androgen (AR) receptors. The developmental profile of testosterone metabolizing enzymes, different in the two sexes, is therefore of the utmost importance in affecting the bioavailability of the steroids active in brain differentiation. Widely diffused pollutants, like polychlorinated biphenyls (PCBs) are able to affect the production and/or action of testosterone metabolites, exerting detrimental influences on reproduction and sex behavior. The main studies performed in our and other laboratories concerning the pattern of expression and the control of the enzymatic systems involved in brain androgen action and metabolism are shortly reviewed. Some recent data on the influence exerted by PCBs on these metabolic systems are also reported.
Sexual differentiation of the rodent hypothalamus : hormonal and environmental influences / P. Negri-Cesi, A. Colciago, A.M. Pravettoni, L. Casati, L. Conti, F.M. Celotti. - In: JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY. - ISSN 0960-0760. - 109:3-5(2008), pp. 294-299.
|Titolo:||Sexual differentiation of the rodent hypothalamus : hormonal and environmental influences|
NEGRI CESI, PAOLA (Primo)
COLCIAGO, ALESSANDRA MARIA (Secondo)
CONTI, LUCIANO (Penultimo)
CELOTTI, FABIO MARIA (Ultimo)
|Parole Chiave:||5Alpha reductase types 1 and 2; Aromatase; Brain sex differentiation; PCB; Pollution; Rat|
|Settore Scientifico Disciplinare:||Settore BIO/09 - Fisiologia|
Settore MED/04 - Patologia Generale
Settore BIO/16 - Anatomia Umana
Settore BIO/14 - Farmacologia
|Data di pubblicazione:||2008|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.jsbmb.2008.03.003|
|Appare nelle tipologie:||01 - Articolo su periodico|