Effect of glucocorticoids on development of the membrane resting potential of chick embryo brain cells in culture

Progressive increase in membrane resting potential (MRP) values in cultured chick embryo brain neurons were recorded from days 2 to 10 of development. Application of corticosterone or prednisone in 24 hr old cultured cells caused a significant increment in MRP recorded at day 2 of culture with respect to control. When ouabain was added to the corticosterone treated cells its effect on the MRP was impaired. An increment in protein synthesis and a reduction in sodium concentration were also observed in corticosterone pretreated cells. These results show that corticoids accelerate the differentiation process in cultured cells particularly the MRP, stimulating perhaps the Na+‐K+ ATPase pump.