The effect of estrogen deficiency on learning and memory in two novel rat models of Alzheimer's disease

Abstract

Alzheimer's disease is a progressive neurodegenerative disorder that results in synaptic and neuronal loss in regions of the brain responsible for memory and cognition. To date, transgenic animal models have played a crucial role in our understanding of the underlying mechanisms of the disease. In the present studies, behavioral performance was assessed in two strains of transgenic rats that overexpress human beta amyloid precursor protein. After behavioral deficits were established, females were used to assess the effect of estrogen deficiency on these deficits. Previous research suggests an increased vulnerability for females to Alzheimer disease-like pathology; while the underlying causes for this are unclear, it has been suggested that estrogens have numerous neuroprotective effects and that the loss of estrogens during aging and menopause may accelerate disease-like pathology. Both types of transgenic rats showed behavioral deficits compared to age-matched non-transgenic control rats and estrogen deficiency exacerbated behavioral symptoms reflective of Alzheimer's disease.