HORMONAL-REGULATION OF HYPOTHALAMIC GENE-EXPRESSION - IDENTIFICATION OF MULTIPLE NOVEL ESTROGEN-INDUCED GENES

Estrogen (E) has been shown to play a major role in hypothalamic funct ion and is a prerequisite for progesterone (P) induced sexual behavior in female rats. In the course of studies in search of steroid induced hypothalamic genes, we discovered a surprisingly large number of E-in duced genes (21 mRNAs in total). This is the largest number off-induce d genes ever identified in a single organ. Many of these mRNAs exhibit considerable magnitudes of induction and their levels were maintained typically during subsequent P treatment. Among the induced genes, sev eral encode metabolic enzymes and may account for some of the morpholo gical changes observed in hypothalamic neurons in response to E. Since E appears to play a major role in defining the pattern of hypothalami c gene expression in conjunction with its capacity for behavioral modu lation, these newly identified cDNAs may serve as genetic markers for correlative studies off-induced central nervous system behavior.