title: [Study on phenotypical activity of isoenzyme CYP3A4 in children].
abstract: The urine levels of cortisol and 6-beta-hydroxycortisol in 30 healthy children were determined with high performance liquid chromatography. The activity of cytochrome P450 isoenzyme CYP3A4 was estimated by the ratio of 6-beta-hydroxycortisol and cortisol. Differences in the CYP3A4 activity depended on the age sex. At the age of 4 to 9 years the value of the ratio was 9.21 +/- 0.67 which in fact was statistically higher than that in the children at the age of 0 to 3 years (p<0.001). In the female children at the age of 0 to 3 years the value of the isoenzyme CYP3A4 activity was actually lower (p<0,05) vs. the female children of the higher ages and the male children at the age of 0 to 3 years. The results are useful for further researches on improvement of drugs dosing and prevention of adverse reactions.
authors: B I
authors: BI
authors: Kantemirova
authors: A Kh
authors: AKh
authors: Chernysheva
authors: A K
authors: AK
authors: Starodubtsev
authors: D A
authors: DA
authors: Sychev
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000375:Aging / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D051544:Cytochrome P-450 CYP3A / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007223:Infant; D007231:Infant, Newborn; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008297:Male; D010641:Phenotype; D012727:Sex Characteristics
chemical_list: D007527:Isoenzymes; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D006854:Hydrocortisone