摘要
目的研究布地奈德2个差向异构体在大鼠肝微粒体孵育体系中的酶促反应动力学。方法超速离心法制备大鼠肝微粒体,采用高效液相色谱法测定布地奈德2个差向异构体在大鼠肝微粒体孵育体系中的浓度。结果布地奈德与大鼠肝微粒体孵育后,2个差向异构体的代谢存在差异,在孵育初期或微粒体酶浓度较低时,22R-布地奈德的代谢较快,随着孵育时间的延长或微粒体酶浓度的增加,22S-布地奈德的代谢明显多于22R-布地奈德;22S-布地奈德的K_m、V_(max)约为22R-布地奈德的2倍。结论布地奈德差向异构体的这种代谢差异与22R-布地奈德的亲和力较高(K_m小于22S-布地奈德)、V_(max)值较小有关。
Objective To identify the differences of the enzymatic reaction kinetics of two epimeric isomers of budesonide in rat liver microsomes.Methods The rat liver microsomes（RLM）was prepared by ultracentrifugation,and the concentration of epimeric isomers of budesonide co-incubated with RLM were determined by high performance liquid chromatography.Results The metabolic differences of two isomers of budesonide were observed after budesonide incubated with RLM.The metabolism of 22R-budesonide was faster than that of 22S-isomer in the early stage of incubations or at low concentration of microsomal enzyme used.However,with the prolongation of incubation time or increased concentration of microsomal enzyme,the metabolism of 22S-budesonide was obviously faster than 22R-isomer.The values for K_mand V_（max） of 22R-budesonide were about 2times greater than those of the epimer（22S）.Conclusion The higher affinity for 22R-budesonide and with a small value of V_（max）,was the main reason for the presented metabolic profile of epimeric isomers of budesonide.
出处
《河北医科大学学报》
CAS
2016年第5期558-561,566,共5页
Journal of Hebei Medical University
基金
廊坊市科学技术研究与发展计划(2014013055)
关键词
布地奈德
微粒体
肝
大鼠
budesonide
microsomes
liver
rats
作者简介
刘艳双（1977-），女，河北永清人，河北省永清县人民医院主治医师，医学学士，从事儿科疾病诊治研究。
通讯作者。E-mail：guowei8043586@sina．com
