Loss of 3H-corticosterone binding capacity in hippocampal slices maintained in vitro

Nuclear uptake of 3H-corticosterone was studied in hippocampal slices subjected to varying periods of preincubation before application of steroid. Uptake capacity declined rapidly toward nonspecific levels over the course of 3 hours from the time of cutting. Glucocorticoid receptors in the cytosol fraction of hippocampal slices also were found to decline, and Scatchard analysis indicated a loss of corticosterone binding sites rather than a change in binding affinity. These results are discussed in terms of the reported effects of corticosterone in vitro.