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The activity was measured of the acetylcholine catabolising enzyme acetylcholinesterase (AChE) in brain after necropsy of seven patients from one established pedigree with dominantly-inherited olivopontocerebellar atrophy (OPCA), a cerebellar ataxia disorder in which neuropathological changes are assumed to be primarily restricted to cerebellum, lower brain stem and spinal cord. Mean AChE activity was significantly reduced in cerebral (-51% to 65%) and cerebellar (-47%) cortex with a less severe change (-37%) in the hippocampus. The magnitude of the enzyme reduction in cerebral cortex was equal to or greater than that reported in brain of demented Alzheimer's and Parkinson's disease patients having loss of AChE-containing nucleus basalis cholinergic neurons. It is concluded that the data provide additional biochemical evidence suggesting a cerebral cortical cholinergic denervation in OPCA. [ABSTRACT FROM AUTHOR]

We measured neurotransmitter markers in autopsied brain of infants with glycine encephalopathy (GE). Because patients with GE develop intractable seizures, special attention was devoted to those neurotransmitter systems implicated in human epilepsy. Mean levels of glycine in the frontal cortex of GE patients were three times higher than control values. No abnormalities were observed for concentrations of gamma-aminobutyric acid (and related receptors), other major neurotransmitter amino compounds, or activities of cholineacetyltransferase and aspartate aminotransferase. Mean acetylcholinesterase activity was significantly elevated by 46%. As experimental data suggest, glycine markedly potentiates the action of the excitatory neurotransmitter glutamic acid. To the extent that the brain seizures in patients with GE can be explained by this mechanism, pharmacotherapy with excitatory amino acid antagonists may represent a new approach to the treatment of GE.

We measured the activities of the cholinergic marker enzymes choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in autopsied brains of seven infants (age range 3 months to 1 year) with Down's syndrome (DS), a disorder in which virtually all individuals will develop by middle age the neuropathological changes of Alzheimer's disease accompanied by a marked brain cholinergic reduction. When compared with age-matched controls cholinergic enzyme activity was normal in all brain regions of the individuals with infant DS with the exception of above-normal activity in the putamen (ChAT) and the occipital cortex (AChE). Our neurochemical observations suggest that DS individuals begin life with a normal complement of brain cholinergic neurons. This opens the possibility of early therapeutic intervention to prevent the development of brain cholinergic changes in patients with DS.