[Effect of bromocriptine on secretion of the enzyme dopamine-B-hydroxylase (DBH) in patients with Parkinson's disease].

The activity of DBH enzyme was measured in plasma of 7 non treated patients suffering from Parkinson's disease; a 10 mg dose of Bromocryptine was administered per os to these patients. Attained results were compared to the enzyme activity in a group of control of 7 healthy individuals. It was pointed out that in patients suffering from Parkinson's disease the decrease of DBH level in plasma after the administration of Bromocryptine was of 32.6% +/- SE 4.4% while in the group of control the decrease was only of 15% +/- SE 4.9%. This decrease in the plasmatic level of the enzyme after the administration of Bromocryptine should be due to the marked antagonistic activity of Bromocryptine on pre-synaptic dopaminergic receptors. This should mean that peripheric pre-synaptic dopaminergic receptors are involved in the physiopathology of Parkinson's disease.