中国成人肝微粒体P450酶活性研究

目的观察中国成人肝微粒体细胞色素P450（CYP450）、细胞色素b5（CYb5）的含量及常见几种药物代谢酶活性水平及在性别、民族间的分布差异。方法肝组织匀浆10000×g离心去除沉淀，再以100000×g超速离心60min，取沉淀加PBS甘油缓冲液，充分溶解制成微粒体悬液，用Lowry法测定蛋白含量；用双光道紫外分光光度计测定CYP450和CYb5的含量及P450酶活性。结果48例成人肝微粒体CYP450和CYb5含量分别为（0．46±0．07）nmol／mg和（0．44±0．04）nmol／mg；男性组CYP450和CYb5含量分别为0．49±0．05）nmol／mg和（0．46±0．06）nmol／mg，均高于女性组的（O．41±0．08）nmol／mg、（O．42±0．05）nmol／mg，P〈0．05；汉族、回族和壮族3个民族P450和CYb5含量作q检验进行两两比较，各组间差异均无统计学意义（P〉0．05）。药物代谢酶NADPH细胞色素C还原酶（NR）、乙基吗啡N-脱甲基酶（EDM）、氨基比林N-脱甲基酶（ADM）、苯并芘羟化酶（BPH）和戊巴比妥侧链羟化酶（PSCH）等酶活性水平分别为（0．71±0．13）nmol／（mg·min），（0．89±0．18）nmol／（mg·min），（0．99±0．17）nmol／（mg·min），（0．07±0．01）nmol／（mg·min），（4．15土0．65）μmol／（mg·min），其中EDM活性水平女性组高于男性组（P〈0．05），PSCH活性水平男性组高于女性组（P〈0．05），其他各种酶活性男女之间无显著性差异；上述5种酶活性水平经q检验，汉族、回族和壮族3个民族之间差异无统计学意义（P〉0．05）。结论测定了中国成人肝微粒体CYP450、CYb5含量及NR，EDM，ADM，BPH，PSCH等酶活性水平，男性组CYP450、CYb5含量及PSCH活性高于女性组，而EDM活性水平女性组高于男性组，上述7种指标在汉族、回族和壮族之间差异均无统计学意义。

Study on the activities of seven enzymes in Chinese adults

Objective To measure the contents,activities,sex difference and nationality distribution of seven enzymes including Chinese adults liver microsome cytochrome P450 (CYP450), cytochrom b5 (CYb5), NDAPH cytochrome C reductase (NR),ethylmorphine N-demethylase (EDM),aminopyrine N- demethylase (ADM),benzopyrene hydroxylase (BPH), and pentobarbital side chain hydroxylase (PSCH).Methods Liver tissue plasm was centrifugated with 10 000×g centrifugal force to remove deposit, then 100 000×g ultracentrifugated for 60 min. The deposit was dissolved with PBS-glycerin buffer as liver microsome suspension. Lowry method was applied to measuring its protein content. The contents of CYP450 and CYb5, as well as microsome P450 enzymatic activity were measured by ultraviolet and visible spectrophotometry.Results The contents of Chinese liver microsome CYP450 and CYb5 in 48 cases were (0.46±0.07) nmol/mg and (0.44±0.04) nmol/mg microsome protein respectively, and the contents in male group [(0.49±0.05) nmol/mg, (0.46±0.06)nmol/mg] were significantly higher than those in female group [(0.41±0.08) nmol/mg, (0.42±0.05)nmol/mg] (P<0.05).The activities of drug-metabolic enzymes (NR, EDM, ADM, BPH and PSCH) were(0.71±0.13)nmol/mg,( 0.89±0.18)nmol/mg,( 0.99±0.17)nmol/mg, was significantly higher in female group than that in male group;while the activity of PSCH was significantly higher in male group than that in female group (P<0.05). There were no statistical differences of the other drug-metabolic enzymes between males and females. There were no statistical differences of the contents or activities of the above seven enzymes among Han, Hui and Zhuang people via q test (P>0.05).Conclusion The contents of CYP450 and CYb5, as well as PSCH are much higher in male group than those in female group, while the activity of EDM is significantly higher in female group than that in male group. There are no statistical differences of the contents or activities of the above seven enzymes among Han, Hui and Zhuang people.