Effect of pirenzepine on the N-demethylation of D(−)ephedrine and ethylmorphine by rabbit liver microsomes

✍ Scribed by H. A. El-Obeid; K. A. Al-Rashood; H. A. Al-Khamees; K. I. Al-Khamis; M. S. Mian

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 301 KB
• Volume: 14
• Category: Article
• ISSN: 0142-2782
• DOI: 10.1002/bdd.2510140310

✦ Synopsis

The possible interaction of pirenzepine with the mixed-function oxidases obtained from phenobarbital-pretreated rabbit microsomes was examined in vitro. Under experimental conditions that did not lead to its own N-demethylation, the drug inhibited the microsomal oxidase systems responsible for the N-demethylation of D(-)ephedrine and ethylmorphine. Kinetic studies showed that pirenzepine inhibited the metabolism of both drugs in a competitive manner. The results indicated that the observed pirenzepine stability to the hepatic N-demethylating system is not a result of low affinity of the drug to the system.