Regulation of glucocorticosteroid receptor expression in rat hippocampal cell cultures by nerve growth factor

Dispersed hippocampal cells cultured in serum-free conditions were used to study the effects of nerve growth factor (NGF) on the expression of type I (mineralocorticosteroid or MR) and type II (glucocorticosteroid or GR) corticosteroid receptors. Cells, plated at a density of 1.2 x 10(6) cells/ml in 60 mm Petri dishes, were mainly identified as neurons (90-95%) and maintained for at least 2 weeks. A 7-day treatment with 10-50 ng NGF/ml induced a concentration-dependent decrease of GR binding (40% decrease) compared to untreated cells. In contrast, MR density was unaffected by a 7-day treatment with 50 ng NGF/ml. Data are discussed as possible direct and/or indirect effects of NGF at the level of both neuronal and glial cells.