Correlation of nicotinic receptor binding with clinical and neuropathological changes in Alzheimer's disease and dementia with Lewy bodies

We investigated the relationship between the loss of nicotinic acetylcholin e receptors (nAChR) and the cognitive decline or neuropathological changes seen in Alzheimer's Disease (AD) and dementia with Lewy bodies (DLB). Midfr ontal (MF) cortex of 31 AD, 24 DLB and 11 nondemented controls was examined . Total plaque (TP), neuritic plaque (NP) and neurofibrillary tangle (NFT) counts were obtained. NAChR binding was assayed using H-3-epibatidine [H-3- EPI]. Last Blessed Information-Memory-Concentration scores (BIMC), Mini-Men tal State Examination (MMSE), Mattis Dementia Rating Scale (DRS) scores wer e collected. There were no correlations between H-3-EPI binding and TP, NP, NFTs counts in either AD or DLB. Last BIMC, MMSE, DRS scores did not corre late with IH-EPI binding in AD or DLB. Thus, decline in cognitive function does not correlate with loss of nAChR in DLB or AD at the end of life sugge sting that later in these diseases, loss of nAChR binding is not a reliable marker of cognitive function in AD or DLB. Loss of nAChR activity does not appear to be related to plaques or NFTs in AD or DLB.