Compensatory Changes in the Noradrenergic Nervous System in the Locus Ceruleus and Hippocampus of Postmortem Subjects with Alzheimer's Disease and Dementia with Lewy Bodies

摘要: In Alzheimer's disease (AD), there is a significant loss of locus ceruleus (LC) noradrenergic neurons. However, functional and anatomical evidence indicates that the remaining neurons may be compensating for loss. Because system plays an important role in learning memory, it to determine whether compensation occurs LC hippocampus subjects with AD or related dementing disorder, dementia Lewy bodies (DLB). We observed profound neuronal DLB three major changes consistent compensation: (1) increase tyrosine hydroxylase (TH) mRNA expression neurons; (2) sprouting dendrites into peri-LC dendritic zone, as determined by α2-adrenoreceptors (ARs) norepinephrine transporter binding sites; (3) axonal projections α2-ARs. subjects, postsynaptic α1-ARs were normal elevated. Expression α1A- α2A-AR not altered, but α1D- α2C-AR was significantly reduced subjects. Therefore, occurring neurons, does appear specific AR hippocampus. these markers versus similar (except TH somewhat greater subjects), presence addition plaques tangles further affect compensatory changes.