INTERACTIONS BETWEEN HORMONAL AND ENVIRONMENTAL SIGNALS ON HYPOTHALAMIC NEURONS - MOLECULAR MECHANISMS SIGNALING ENVIRONMENTAL EVENTS

It is axiomatic that the central nervous system must manage the integr ation of several environmental factors with steroid hormonal influence s for the biologically adaptive performance of reproductive behavior. Launching from established behavioral investigations and from hormonal influences on gene function in the brain, we review here studies on h ow synaptic inputs and sex hormone influences codeter-mine hypothalami c gene expression. A particularly exciting implication of results on t he ability of thyroid hormone receptors to interfere with estrogen rec eptor-dependent neuroendocrine function is that environmentally stimul ated changes in thyroid hormone levels could influence hypothalamic tr anscriptional mechanisms important for behaviour. If so, this would un ite naturalistic environmental thinking with molecular neurobiological thinking important for the hypothalamic control of reproduction. (C) 1997, Elsevier Science Inc.