The effects of L-DOPA on regional cerebral blood flow and oxygen metabolism in patients with Parkinson's disease.
Studies performed on 18 patients with Parkinson's disease and 6 control subjects have shown that acute administration of L-DOPA in clinically effective doses gives rise to a diffuse increase in regional cerebral blood flow without accompanying stimulation of regional oxygen utilization. The data suggest that this rise in rCBF is caused by vasodilatation due to a direct action of the drug on the cerebral blood vessels. The effect of L-DOPA on rCBF did not correlate with the degree of clinical improvement seen in each patient after treatment. The therapeutic effect of L-DOPA in the brain was not reflected in any change of regional cerebral oxygen utilization as measured by our technique. We suggest that the pharmacological actions of L-DOPA in the brain take place on at least two different levels.
D000328:Adult; D000368:Aged; D002540:Cerebral Cortex / Q000378:metabolism / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000187:drug effects*; D010300:Parkinson Disease / Q000378:metabolism / Q000503:physiopathology*
D007980:Levodopa