苯环喹溴铵对大鼠肝脏CYP450酶诱导作用的研究

Study on Induction of Rat Liver Cytochrome P450 Enzymes by Bencycloquidium Bromide

目的研究苯环喹溴铵对大鼠肝脏CYP450酶是否有诱导作用。方法将SD大鼠,分为空白溶剂组、阳性对照组和苯环喹溴铵低中高剂量给药组(分别鼻腔给予苯环喹溴铵生理盐水溶液1,3或9 mg·kg-1),分别于连续给药后处死,取肝称重并制备微粒体。计算大鼠肝脏脏器系数;测定大鼠肝脏微粒体CYP450蛋白含量;通过HPLC-MS/MS测定大鼠肝微粒体温孵体系中6β-羟基睾酮和对乙酰氨基酚的浓度;应用底物法测定大鼠肝微粒体CYP1A1/2和CYP3A1/2酶的活性。结果阳性对照组与空白溶剂组相比,在大鼠肝脏脏器系数、CYP450蛋白含量及CYP1A1/2和CYP3A1/2酶活性上均有增加,且具有显著性差异(P<0.05)。苯环喹溴铵低中高剂量给药组与空白溶剂组在肝脏脏器系数、CYP450蛋白含量和CYP1A1/2酶活性上均无显著性差异(P>0.05);苯环喹溴铵低中高剂量给药组大鼠肝脏CYP3A1/2酶的活性未高于空白溶剂组。结论阳性对照组对大鼠肝脏CYP450酶有诱导作用,所建立的实验体系可用于诱导作用的评价;苯环喹溴铵低中高3个剂量组对大鼠肝脏CYP450酶均无诱导作用。

OBJECTIVE TO study the induction effect of bencycloquidium bromide （BCQB） on rat liver cytochrome P450 en- zymes. METHODS Rats were divided into solvent control group, positive control （phenobarbital） group and BCQB group. The rats in BCQB groups were intranasally administered with 1, 3, and 9 mg · kg^-1 BCQB, respectively. After multiple-dose administration, the rats were sacrificed, and the livers were weighed and prepared to mierosomes. Then the liver coefficients were calculated, and the total content of CYP450 enzymes in liver microsomes was determined by speetrophotometer. HPLC-MS/MS method was adopted and validated to simultaneously determine the productive velocity of 6β-hydroxyl testosterone and paracetamol after incubation of rat liver mi- crosomes. The activities of CYP1A1/2 and CYP3A1/2 were measured according to the productive velocity. RESULTS The liver co- efficients, total content of CYP450 enzymes, and activity of CYP1A1/2 were significantly different （P 〈 0. 05 ） between solvent control group and positive control group, while comparable （P 〉 0. 05 ） between solvent control group and BCQB groups. The activity of CYP3A1/2 in BCQB groups was not higher than solvent control group. CONCLUSION Phenobarbital has induction effect on rat liver CYP450 enzymes. The test system can be used to evaluate the induction effect of BCQB on rat liver CYP450 enzymes. BCQB has no induction effect on liver CYP450 enzymes in rats.