Expression of key steroidogenic enzymes in developing brain: hormonal compensation of sex chromosomes-induced sex differences

Abstract

Developing brain of mammals is organized by gonadal steroids during the critical period of sexual differentiation (E18-PN10). The regulatory role of neurosteroids in the early brain is unclear. It is known that 17-β-estradiol (E2) is produced within the brain itself primarily due to local aromatization of gonadal testosterone and also due to de novo synthesis from cholesterol.

Little is known about the circulating and local levels of steroids in the embryonic brain. Thus, the use of animal models that dissociate the effect of gonadal sex from sex chromosomes heritage facilitates the study of organizational actions of gonadal steroids and neurosteroids in each sex.