Studies of Pyridoxal-Penicillamine Antagonism in the Human

摘要

The pyridoxal-L-penicillamine antagonism previously studied by others in lower animals has now been studied in man by means of urinary xanthurenic acid (XA) excretion levels. Subjects of the present study, all Chinese, included 21 normal individuals and 2 patients with Wilson's disease. The studies involved urinary XA determinations, with and without tryptophan-loading tests, and with varying dosage combinations of penicillamines and pyridoxine hydrochloride. It was found that urinary XA excretions remained normal after DL-penicillamine or DL-tryptophan alone but increased when the two were taken together; pyridoxine hydrochloride prevented the increase. No increases in urinary XA excretion occurred when Dpenicillamine or N-acetyl-DL-penicillamine were used in place of the DL-penicillamine during tryptophan loading. These results support the thesis that a pyridoxal-Lpenicillamine antagonism can operate in the human, both in normal individuals and in those with Wilson's disease.(Author)