title: CYP3A5 polymorphism and sensitivity of blood pressure to dietary salt in Japanese men.
abstract: The cytochrome P-450 3A5 (CYP3A5) gene has recently been implicated in renal sodium reabsorption and blood pressure regulation. The genetic effect of CYP3A5*1 (expressor) and *3 (reduced-expressor) variants on blood pressure has been studied in African Americans and Caucasians, but not yet in the Asian population. In this cross-sectional study, 238 Japanese male workers were examined to determine whether CYP3A5 *1*3 affects the blood pressure level, taking daily salt intake into account as a potential gene-environment interaction. The A6986G polymorphism was determined by melting curve analysis, and the salt intake level was inferred from spot urine specimen by calculating 24-h urinary sodium excretion. CYP3A5 *1*3 per se had no association with systolic blood pressure (SBP) and only a weak association was detected for diastolic blood pressure (DBP) (*1/*1 vs *3/*3, P=0.038), which was strengthened after adjustment with age and body mass index (*1/*1 vs*3/*3, P=0.007; *1/*1 vs*1/*3, P=0.045). Significant interactions between the genotype and salt intake were observed in both SBP (P=0.046) and DBP (P=0.003). SBP and DBP were significantly associated with the level of salt intake in*3/*3 (P<0.001) but not in *1 carriers. *1carrier had higher blood pressure than *3/*3, but only in those with low salt intake. These results suggest that CYP3A5 variants may be a determinant of salt sensitivity of blood pressure in Japanese men.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health and Family Medicine, Capital Medical University, Youanmenwai, Beijing, PR China.
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: K
authors.initials: K
authors.lastname: Miyaki
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Muramatsu
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D003430:Cross-Sectional Studies; D003469:Culture; D051544:Cytochrome P-450 CYP3A / Q000235:genetics*; D004032:Diet; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000208:ethnology / Q000235:genetics / Q000503:physiopathology; D007564:Japan; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D017673:Sodium Chloride, Dietary / Q000494:pharmacology*
chemical_list: D017673:Sodium Chloride, Dietary; C510164:CYP3A5 protein, human; D051544:Cytochrome P-450 CYP3A