Stereoselective metabolism of metoprolol in Caucasians and Nigerians--relationship to debrisoquine oxidation phenotype.
The relationship between debrisoquine oxidation phenotype and the stereoselective metabolism of metoprolol was investigated in populations of British Caucasians (n = 139) and Nigerian subjects (n = 117). The 0-8 h urinary S/R-metoprolol (S/R-M) ratio was related to the ability to metabolise metoprolol and debrisoquine in both ethnic groups. The median S/R-M ratio was significantly higher in Caucasians (1.27) than in Nigerians (1.10). In the Caucasian population poor metabolisers of debrisoquine had significantly lower S/R-M ratio (median = 0.84) than extensive metabolisers (median = 1.28). Bimodality in the frequency distribution of the S/R-M ratio was not apparent in either ethnic group.
University Department of Pharmacology and Therapeutics, Royal Hallamshire Hospital, Sheffield.
M S
MS
Lennard
G T
GT
Tucker
H F
HF
Woods
J H
JH
Silas
A O
AO
Iyun
D001711:Biotransformation; D044383:Black People; D003647:Debrisoquin / Q000378:metabolism*; D006801:Humans; D007546:Isoquinolines / Q000378:metabolism*; D008790:Metoprolol / Q000378:metabolism* / Q000493:pharmacokinetics; D009549:Nigeria; D010084:Oxidation-Reduction; D010641:Phenotype; D013237:Stereoisomerism; D044465:White People
D007546:Isoquinolines; D008790:Metoprolol; D003647:Debrisoquin