Some cerebral proteins and enzyme systems in Alzheimer's presenile and senile dementia.

The water-soluble proteins of the cerebral gray matter and some enzyme systems (cholinesterase, acetylcholinesterase, lactate dehydrogenase, malate dehydrogenase, acid phosphatase) were studied in 9 autopsy cases of Alzheimer's presenile or senile dementia, 1 case of Pick's disease and 1 case of cerebral arteriosclerosis. The proteins and enzyme patterns were visualized on polyacrylamide gradient gels after electrophoresis. In all patients studied, the profiles of cerebral gray-matter proteins were normal. In the patients with advanced dementia, the enzyme patterns usually were abnormal. Particularly in Alzheimer's disease, the activity of malate dehydrogenase was markedly increased.