HORMONAL-REGULATION OF OPIOID PEPTIDE NEURONS IN THE ANTEROVENTRAL PERIVENTRICULAR NUCLEUS

Steroid hormones provide a means of coordinating the activity of wides pread neural systems that mediate endocrine, autonomic, and somatomoto r aspects of reproductive processes that are essential for the propaga tion of mammalian species. Because these processes are quite different in each sex, the neural pathways that control them are also sexually differentiated. The anteroventral periventricular nucleus (AVPV) of th e preoptic region occupies a nodal point in sexually dimorphic forebra in circuits and appears to play a critical role in regulating gonadotr opin secretion. The AVPV contains sexually dimorphic populations of op ioid peptide containing neurons that display different patterns of dev elopment and are differentially regulated in adult animals by gonadal steroids. Moreover, estrogen (ER) and progesterone (PR) receptors are expressed in AVPV neurons in a transmitter-specific way, and the expre ssion of these nuclear transacting factors is differentially regulated by sex steroids. Thus, neurons in the AVPV show distinct patterns of hormonal regulation of gene expression, and distinct hormone receptor profiles. (C) 1994 Academic Press, Inc.