title: Lewy body disease: thalamic cholinergic activity related to dementia and parkinsonism.
abstract: Within the spectrum of Lewy body disease cognitive impairment occurs in PD with dementia (PDD) and dementia with Lewy bodies (DLB). Although neocortical cholinergic deficits are associated with cognitive impairments in PDD and DLB, no neurochemical study has been published describing the thalamic cholinergic activity whereas the thalamus plays a major role in modulating cortical activity. Choline acetyltransferase (ChAT) activity was analyzed in reticular (Re), mediodorsal (MD) and centromedian (CM) thalamic nuclei in series of nine controls, five DLB with parkinsonism (DLB + P), five DLB without parkinsonism (DLB - P), six PD without dementia and 14 PDD cases. Significant reductions in ChAT were apparent in PDD as follows: in Re and MD nuclei compared with controls; in MD and CM nuclei compared with DLB + P; and in MD compared with PD. Increased ChAT activity was found in CM nuclei in DLB + P compared with DLB - P. These findings show that significant thalamic presynaptic cholinergic deficits occur only in cases of combined cortical and subcortical neurodegeneration in which dementia developed after prolonged parkinsonism.
authors.affiliation: Institute for Ageing and Health, MRC Building, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK. iryna.ziabreva@ncl.ac.uk
authors.forename: Iryna
authors.initials: I
authors.lastname: Ziabreva
authors.forename: Clive G
authors.initials: CG
authors.lastname: Ballard
authors.forename: Dag
authors.initials: D
authors.lastname: Aarsland
authors.forename: Jan-Petter
authors.initials: JP
authors.lastname: Larsen
authors.forename: Ian G
authors.initials: IG
authors.lastname: McKeith
authors.forename: Robert H
authors.initials: RH
authors.lastname: Perry
authors.forename: Elaine K
authors.initials: EK
authors.lastname: Perry
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002795:Choline O-Acetyltransferase / Q000378:metabolism*; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000201:enzymology*; D008297:Male; D010300:Parkinson Disease / Q000201:enzymology*; D013788:Thalamus / Q000201:enzymology*; D014018:Tissue Distribution
chemical_list: D002795:Choline O-Acetyltransferase