[The polymorphism of pachycarpine oxidation].

The ratio of urinary excretory pachycarpine to its oxidized metabolites, 2- and 5-dehydropachycarpines (metabolic ratio) was determined in a selective group of 81 unrelated cardiac patients from a Moscow Caucasian population given pachycarpine in a dose of 25 g. The metabolic ratio distribution was shown to be bimodal. Ninety five per cent of the patients had the metabolic ratio lower than 28 while 4 (5%) patients higher than 70. In 25 patients of the group, the pachycarpine metabolic ratio was evaluated after quinidine, 50 mg. Twenty-two patients with a relatively low metabolic ratio showed a dramatic (several times) increase, while in 3 patients with the prior metabolic ratio higher than 70, the effect of quinidine was insignificant. The findings suggest that pachycarpine oxidation is genetically polymorphic and similar to the polymorphism of sparteine/debrisoquine oxidation. Pachycarpine may be used as a marker in phenotyping the population.