[Kinetics of tramal, benzofurocain and amidopyridine demethylation under inhibitory conditions produced by cimetidin, orthophen and thiamine diphosphate].

Demethylation kinetics of analgetics tramal, benzofurocain and amidopyrine has been studied through the experiments on microsomal fraction of white rats' liver. It was found that tramal demethylation is apparently catalysed with the help of two enzymes, possessing various affinities towards the substrate. Kinetics of benzofurocain and amidopyrine demethylation is satisfactory described with the help of Michaelis-Menten equation. Cimetidine, thiamine diphosphate and orthophen (at concentrations close to therapeutic ones) exhibit mixed-type inhibition in respect of all three demethylaze substrates under study.