Evidence for a change in neurotransmitter affecting oesophageal motility in Parkinson's disease

In a study of oesophageal motility in 20 patients with Parkinson's disease, intravenous atropine produced marked disruption of co-ordination in response to swallows, when compared with control subjects. This suggests that cholinergic rather than dopaminergic mechanisms are more important in the control of swallowing in patients with Parkinsonism. No conclusive evidence of peripheral dopamine depletion or autonomic neuropathy was found, although minor changes suggestive of the former were found in severely affected patients.