Nicotinic receptor losses in dementia with Lewy bodies: comparisons with Alzheimer's disease

We sought to delineate differences between alpha 7 nicotinic acetylcholine receptor (nAChR) levels in Alzheimer's disease (AD), dementia with Lewy bod ies (DLB) and age matched controls, as well as the correlations between alp ha 7 or non-alpha 7 nAChR levels and synaptophysin (Syn) or choline acetylt ransferase (ChAT) in DLB. Mean bungarotoxin (Bgt) binding was 2.7 +/- 1.1 f or controls, 2.4 +/- 1.0 for AD and 1.4 +/- 0.5 for DLB. There were signifi cant decreases in Bgt binding for the DLB group compared to either controls or AD. Mean epibatidine (Epi) binding was 14.8 +/- 3.2 for controls, 6.3 /- 3.2 for AD and 7.1 +/- 2.4 fmoles/mg protein for DLB. Epi binding in bot h the AD and DLB groups was significantly lower than in the controls. Altho ugh Syn loss correlated with the decrease in Epi binding in both diseases, declining ChAT levels correlated with Epi binding only in DLB. These data d emonstrate a different pattern of nAChR loss in AD and DLB that may, in par t, explain some of the differences in the two phenotypes. (C) 2000 Elsevier Science Inc. All rights reserved.