[Role of catecholamines in the pathogenesis of extrapyramidal hyperkinesis]

The total and cerebral metabolism of catecholamines was studied in 134 patients with various extrapyramidal hyperkinetic syndromes. Homovanillic acid levels determined in the ventricular and lumbar cerebrospinal fluid served as an indicator of the cerebral metabolism of dopamine. In two patients with hepatocerebral dystrophy (HCD) and torsion dystonia the author studied the content of catecholamines in the cerebral tissue. This study showed a considerable increase in noradrenalin and dopamine levels in the striatum, which was more pronounced in cases of HCD. It has been concluded on the basis of the findings obtained that elevation of cerebral dopaminergic activity is one of characteristic biochemical signs of extrapyramidal hyperkineses. There was a significant increase in this activity following the destruction of the ventrolateral nucleus of the thalamus, which appears to be one of the biochemical mechanisms underlying an unfavourable effect of stereotaxic surgery for extrapyramidal hyperkineses. The importance of this pathology of noradrenergic systems in the pathogenesis of extrapyramidal diseases remains unclear and needs further investigation.