Tourette's syndrome: A neurochemical analysis of postmortem cortical brain tissue

Postmortem frontal, temporal, and occipital regions of the brain from adult patients who had a diagnosis of Tourette's syndrome were analyzed for neurochemical alterations. In 3 of 4 TS‐affected brains, the concentration of adenosine 3′,5′ ‐monophosphate (cyclic AMP) was reduced in all brain regions evaluated. This diminution in cyclic AMP was not associated with a significant change in the activity of the synthesizing enzyme, adenylate cyclase. No significant differences were identified for the neurotransmitter‐synthesizing enzymes choline acetltransferase and glutamate decarboxylase. Concentrations of dopamine, norepinephrine, and the serotonin metabolite 5‐hydroxyindoleacetic acid were not altered. Postsynaptic receptor‐binding activity for muscarinic cholinergic ([3H] quinuclidiny1 benzilate) and beta receptors ([125I]iodocyanopindolol) showed no generalized impairment. It is suggested that symptoms of Tourette's syndrome might be related to an abnormality within a second messenger system.