title: Effect of L-threo-3,4-dihydroxyphenylserine on regional cerebral blood flow in patients with Parkinson's disease.
abstract: Regional cerebral blood flow (rCBF) was measured by the 133Xe inhalation technique in 9 patients with Parkinson's disease and in 1 patient with pure akinesia before and during treatment with L-threo-3,4-dihydroxyphenylserine (DOPS). L-DOPS alone was administered in 4 patients, and combined with L-DOPA or bromocriptine in 6 patients. The mean, hemispheric and regional CBF was unaffected by the chronic administration of L-DOPS. In addition, no significant difference in the mean CBF was observed between the patients who showed marked or moderate improvement in parkinsonian symptoms during the treatment with L-DOPS and those who showed slight improvement or no change, or between the group treated with L-DOPS alone and the group treated in combination with L-DOPS and other drugs. These results indicate that L-DOPS does not increase the CBF in parkinsonian patients, thus the anti-parkinsonian effects of the agent are not mediated by changes in CBF.
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D015103:Droxidopa / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D012039:Regional Blood Flow / Q000187:drug effects; D012694:Serine / Q000031:analogs & derivatives*
chemical_list: D012694:Serine; D015103:Droxidopa