Markers of serotonin synapses in entire temporal lobe and frontal and temporal neocortex were examined for changes in Alzheimer's disease by use of both neurosurgical and autopsy samples. Uptake of [3H]serotonin, binding of [3H]imipramine, and content of indolamines were all significantly reduced, indicating that serotonin nerve terminals are affected. Binding of [3H]serotonin was also reduced, whereas that of [3H]quinuclidinyl benzilate, [3H]muscimol, and [3H]dihydroalprenolol were unaltered. When the Alzheimer's samples were subdivided according to age, the reduction in [3H]serotonin binding was a feature of only autopsy samples from younger patients. In contrast, presynaptic cholinergic activity was reduced in all groups of Alzheimer's samples, including neurosurgical specimens. Five markers, thought to reflect cerebral atrophy, cytoplasm, nerve cell membrane, and neuronal perikarya were measured in the entire temporal lobe. In Alzheimer's disease the reductions (mean 25%, range 20-35%) were thought to be too large to be due only to loss of structures associated with the presumed cholinergic perikarya in the basal forebrain and monoamine neurones in the brain stem.
To investigate blood-barrier leakage of plasma proteins in acute plaques of multiple sclerosis (MS) the authors used immunocytological methods to examine frozen tissue removed at autopsy from recently active cases. Annular patterns of protein-rich leakage were seen which may help to elucidate the patterns observed using gadolinium-enhanced nuclear magnetic resonance imaging. Vessel wall damage was found in all acute plaques examined and this was associated with the intramural deposition of complement on smooth muscle components and with an infiltration of HLA-DR +ve macrophages. In addition, all acute cases examined had small plaques which contained particulate material within macrophages and astrocytes, on which complement and immunoglobulins colocated. Attempts to find similar material in cases of chronic MS, subacute sclerosing panencephalitis and in perivenous encephalomyelitis were unsuccessful. These results suggest that the inflammatory changes in early MS plaques may have some specificity which could be related to the antigens whose presence is inferred by the colocation of complement and immunoglobulin on material within activated macrophages and astrocytes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.