Object/context-specific memory deficits associated with loss of hippocampal granule cells after adrenalectomy in rats

Abstract

Chronic adrenalectomy (ADX) causes a gradual and selective loss of granule cells in the dentate gyrus (DG) of the rat.Here, we administered replacement corticosterone to rats beginning 10wk after ADX. We then tested them in three discrimination tasks based on object novelty, location, or object/context association. Only during testing of the object/context association did ADX rats demonstrate deficits. These findings add to a body of evidence that the hippocampus is necessary when contextual information is important.We also confirm that memory deficits after chronic adrenalectomy are not a result of loss of corticosterone per se.