Alpha7 Nicotinic Receptors and MAP Kinase in AD Models

Early stage Alzheimer’s disease is generally observed as hippocampal dysfunction with the inability of the brain to consolidate short-term into long-term memories. These memory deficits are typically present before any generalized dementia or overall cognitive decline is observed. Dr. Sweatt hypothesizes that for the early stages of AD, which are characterized by subtle deficits in memory consolidation; there will be abnormalities in the normal biochemical machinery that underlies memory. He suggests that the MAP kinase signaling cascade plays a critical role in learning and memory. He is examining the transgenic mouse model of AD for MAP kinase signaling defects. He will also examine how the amyloid beta peptide is linked to the MAP kinase cascade. Preliminary results suggest that a receptor for amyloid beta peptide on the cell surface of neurons is the alpha7 nicotinic acetylcholine receptor. Dr. Sweatt will use genetic approaches to examine whether deletion of the alpha7 receptor gene leads to amelioration of memory deficits exhibited in transgenic mice with AD and decreases in biochemical markers. The identification of the alpha 7 receptor involvement in AD allows for the future study of agents that block the receptor as potential therapeutics for AD.