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The Biochemistry of Catecholamines in Relation to Parkinson's Disease
Author(s) -
Hinterberger H.
Publication year - 1971
Publication title -
australian and new zealand journal of medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.596
H-Index - 70
eISSN - 1445-5994
pISSN - 0004-8291
DOI - 10.1111/j.1445-5994.1971.tb02560.x
Subject(s) - homovanillic acid , dopamine , endocrinology , medicine , excretion , catecholamine , dihydroxyphenylalanine , urine , metabolism , ingestion , oral dose , oral administration , serotonin , receptor
Summary: The effect of oral doses of 2–9 g L‐3, 4‐dihydroxyphenylalanine (L‐dopa) on the metabolism of catecholamines was studied in 14 patients with Parkinson's Disease being treated simultaneously with cholinolytic medication. Comparison of the excretion in urine of free and conjugated noradrenalin and adrenalin showed no significant differences before and after three months of medication with L‐dopa. Vanilmandelic acid was moderately increased, indicating stimulation of catecholamine turnover well controlled by homeostatic mechanisms. The excretion of free and conjugated 3, 4‐dihydroxyphenylethyla‐mine (dopamine) and its acidic metabolites 3, 4‐dihydroxyphenylacetic acid and homovanillic acid was increased by a factor of 10 3 ‐10 4 . Peak levels of L‐dopa in plasma were observed 1 ‐5‐3 hours after an oral dose and were found to vary considerably between patients. No relation between plasma levels and improvement scores could be observed. Levels of L‐dopa, homovanillic acid, 3, 4‐dihydroxyphenylacetic acid and 5‐hydroxyindoleacetic acid were measured in lumbar fluid obtained 4–6 hours after ingestion of an oral dose. These levels increased with increasing daily dose (mg/kg). Although the absolute amount of homovanillic acid did not closely follow clinical improvement, absence of homovanillic acid in the CSF was noted in two patients who failed to improve.