Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-9-13
pubmed:abstractText
The hepatic and first-pass cytochrome P4503A (CYP3A) probe alfentanil (ALF) is also metabolized in vitro by CYP3A5. Human hepatic microsomal ALF metabolism is higher in livers with at least one CYP3A5*1 allele and higher CYP3A5 protein content, compared with CYP3A5*3 homozygotes with little CYP3A5. The influence of CYP3A5 genotype on ALF pharmacokinetics and pharmacodynamics was studied, and compared to midazolam (MDZ), another CYP3A probe. Healthy volunteers (58 men, 41 women) were genotyped for CYP3A5 *1, *3, *6, and *7 alleles. They received intravenous MDZ then ALF, and oral MDZ and ALF the next day. Plasma MDZ and ALF concentrations were determined by mass spectrometry. Dark-adapted pupil diameters were determined coincident with blood sampling. In CYP3A5(*)3/(*)3 (n=62), (*)1/(*)3 (n=28), and (*)1/(*)1 (n=8) genotypes, systemic clearances of ALF were 4.6+/-1.8, 4.8+/-1.7, and 3.9+/-1.7 ml/kg/min and those of MDZ were 7.8+/-2.3, 7.7+/-2.3, and 6.0+/-1.4 ml/kg/min, respectively (not significant), and apparent oral clearances were 11.8+/-7.2, 13.3+/-6.1, and 12.6+/-8.2 ml/kg/min for ALF and 35.2+/-19.0, 36.4+/-15.7, and 29.4+/-9.3 ml/kg/min for MDZ (not significant). Clearances were not different between African Americans (n=25) and Whites (n=68), or between CYP3A5 genotypes within African Americans. ALF pharmacodynamics was not different between CYP3A5 genotypes. There was consistent concordance between ALF and MDZ, in clearances and extraction ratios. Thus, in a relatively large cohort of healthy subjects with constitutive CYP3A activity, CYP3A5 genotype had no effect on the systemic or apparent oral clearances, or pharmacodynamics, of the CYP3A probes ALF and MDZ, despite affecting their hepatic microsomal metabolism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0009-9236
pubmed:author
pubmed:issnType
Print
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
410-26
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:17554244-Administration, Oral, pubmed-meshheading:17554244-Adult, pubmed-meshheading:17554244-African Americans, pubmed-meshheading:17554244-Alfentanil, pubmed-meshheading:17554244-Biological Markers, pubmed-meshheading:17554244-Cytochrome P-450 CYP3A, pubmed-meshheading:17554244-Cytochrome P-450 Enzyme System, pubmed-meshheading:17554244-European Continental Ancestry Group, pubmed-meshheading:17554244-Female, pubmed-meshheading:17554244-Gene Frequency, pubmed-meshheading:17554244-Genotype, pubmed-meshheading:17554244-Hispanic Americans, pubmed-meshheading:17554244-Humans, pubmed-meshheading:17554244-Injections, Intravenous, pubmed-meshheading:17554244-Male, pubmed-meshheading:17554244-Midazolam, pubmed-meshheading:17554244-Middle Aged, pubmed-meshheading:17554244-Miosis, pubmed-meshheading:17554244-Phenotype, pubmed-meshheading:17554244-Polymorphism, Genetic, pubmed-meshheading:17554244-Pupil, pubmed-meshheading:17554244-Reference Values, pubmed-meshheading:17554244-Substrate Specificity
pubmed:year
2007
pubmed:articleTitle
Influence of CYP3A5 genotype on the pharmacokinetics and pharmacodynamics of the cytochrome P4503A probes alfentanil and midazolam.
pubmed:affiliation
Division of Clinical and Translational Research, Department of Anesthesiology, Washington University, St Louis, Missouri, USA. kharasch@wustl.edu
pubmed:publicationType
Journal Article, Clinical Trial, Comparative Study, Research Support, N.I.H., Extramural