Primary cell cultures from fetal bovine hypothalamus and cerebral cortex: a reliable model to study P450Arom and alpha and beta estrogen receptors in vitro.

Estrogens synthesized by neural P450 aromatase (P450Arom) are implicated in many aspects of mammalian brain development and particularly in sexual differentiation of the central nervous system (CNS). This study analyzes the usefulness of an in vitro model based on bovine primary cell cultures from the hypothalamus and frontal cortex to investigate the role of P450Arom and estrogen receptors (ERs) in the development of fetal neural structures. The mRNA expression of P450Arom, ERalpha and ERbeta was detected using RT-PCR analysis in both hypothalamic and cortical primary cell cultures. P450Arom was identified and localized by immunocytochemistry in both neurons and astrocytes. Our results indicate that, within our experimental settings, astrocytes do not express ERalpha. The experimental model that we propose may represent a standardized dynamic model to study cellular and molecular mechanisms involved in the complex process of brain sexual differentiation.