Steroid control of higher brain function and behavior.

In higher vertebrates, many behavioral characteristics can be attributed to effects in the central nervous system, in response to gonadal hormones secreted early in development. The lipophilic properties of steroids facilitate their easy passage in free form through the blood-brain barrier. At the cerebral level, the function of many nerve cells is influenced by steroid hormones originating from the periphery (synthesis of gluco-, and mineralo-corticosteroids in the adrenal glands and of sex steroids in the gonads and the placenta from cholesterol). However, the relationship between steroids and cerebral function may need reconsidering in light of the recent discovery of a biosynthetic pathway (independently of peripheral sources) of steroidal compounds ensuring the synthesis of neurosteroids from cholesterol in certain brain cells.