GLIAL FIBRILLARY ACIDIC PROTEIN MESSENGER-RNA INCREASES AT PROESTRUS IN THE ARCUATE NUCLEUS OF MICE

Glial fibrillary acidic protein (GFAP) increases during proestrus in a strocytes of the hypothalamic arcuate nucleus (ARC). These changes are associated with altered astrocyte-neuron contacts and synaptic remode lling, during preparation for the preovulatory gonadotrophin surge. Th is study of young C57BL/6J mice showed transient elevations of GFAP mR NA on proestrus in the ARC by in situ hybridization. Basal GFAP mRNA w as regained within 18 h. We hypothesize that changes in astrocytic GFA P on proestrus result from elevations of GFAP mRNA that are, in turn, driven by ovarian secretions of estradiol.