Removal of adrenal steroids modulates various functions in the brain. However, adrenalectomy (ADX) induced cell death in the hippocampal formation of the adult rat is a recently described phenomenon. We undertook this ultrastructural study on long-term adrenalectomized (5 months) rats to investigate the mode of cell death in the hippocampus. Our results showed apoptotic changes in the hippocampus. In addition we have observed other types of degeneration in the hippocampal neurons. The novel finding in this study is that different morphological patterns of cell death were evident both in the dentate gyrus and in the pyramidal areas, which may reflect different stages of the same death process.