Clinical Chemistry, Karolinska University Hospital, Huddinge, Sweden.
Br J Clin Pharmacol. 2013 Jun;75(6):1536-40. doi: 10.1111/bcp.12016.
To compare plasma 4β-hydroxycholesterol : cholesterol with urinary 6β-hydroxycortisol : cortisol as markers of cytochrome P4503A4 activity before and after treatment with rifampicin for 2 weeks.
6β-hydroxycortisol and cortisol were determined by liquid chromatography tandem mass spectrometry and 4β-hydroxycholesterol was determined by gas chromatography-mass spectrometry in three groups of healthy volunteers.
Induction ratios for 6β-hydroxycortisol : cortisol were 1.8, 3.9 and 4.5 for 20 mg day(-1) , 100 mg day(-1) or 500 mg day(-1) of rifampicin, respectively. The corresponding ratios for 4β-hydroxycholesterol : cholesterol were 1.5, 2.4 and 3.8.
Plasma 4β-hydroxycholesterol : cholesterol gave similar induction ratios to urinary 6β-hydroxycortisol : cortisol.
比较利福平治疗 2 周前后血浆 4β-羟胆固醇:胆固醇与尿 6β-羟皮质醇:皮质醇作为细胞色素 P4503A4 活性的标志物。
三组健康志愿者采用液相色谱串联质谱法测定 6β-羟皮质醇和皮质醇,气相色谱-质谱法测定 4β-羟胆固醇。
利福平 20mg/d、100mg/d 或 500mg/d 时,6β-羟皮质醇:皮质醇的诱导比分别为 1.8、3.9 和 4.5,相应的 4β-羟胆固醇:胆固醇的比值分别为 1.5、2.4 和 3.8。
血浆 4β-羟胆固醇:胆固醇与尿 6β-羟皮质醇:皮质醇的诱导比值相似。