寒证大鼠细胞色素P_(450)亚酶的表征及肉桂的调控

目的:考察寒证大鼠肝脏细胞色素P_(450)(CYP_(450))亚酶的表征特点及热性中药的调控效果。方法:选取知母-石膏-黄柏-龙胆草制备寒性造模药,对SD大鼠诱导21 d后复制寒证模型;另取肉桂提取物对寒性大鼠进行干预,制备观察组;用生理盐水处理为对照组。钙盐沉淀法制备肝脏微粒体,与混合探针药物温孵,用高效液相色谱(HPLC)法测定探针药物的代谢消除百分率,评价CYP_(450)亚酶活性变化。提取肝脏总RNA,实时荧光定量PCR法测定CYP_(450)亚酶的mRNA表达。结果:寒性中药对大鼠CYP3A1酶的活性和mRNA具有显著的抑制作用,热性肉桂具有一定的调控作用,并且这种调控发生在mRNA水平。结论:本研究从多角度系统评价和验证寒证机体CYP_(450)亚酶的表征特点及热性中药的调控效果。

Characterization of CYP450s in Cold Syndrome Rats and the Regulative Effect of Cinnamomum Cassia

To study the characterization of five kinds of CYP450 in the liver of cold syndrome rats and the regulative effect of heat traditional Chinese medicine.Methods:Cold syndrome model was induced in SD rats for 21 days by gavage of Anemarrhena asphodeloides-Gypsum Fibrosuum-Cortex Phellodendri-Gentiana scabra.In addition,cold syndrome rats were treated with Cinnamomum cassia extract to prepare the treatment group.Saline was used as the control medicine.The liver microsomes were prepared by calcium precipitation method,incubated with mixed probe drugs,and the percentage of metabolic elimination of the probe drugs was determined by HPLC method to evaluate CYP450 activity.Total RNA was extracted from the liver and mRNA expression of CYP450s was determined by real-time fluorescent quantitative PCR.Results:The cold medicine can inhibit the activity and mRNA of CYP3A1 in rats.Cinnamomum cassia has a certain regulative effect which took place at mRNA level.Conclusion:This study should be further combined with protein expression experiments to evaluate and verify the characteristics of CYP450 enzyme in cold syndrome and the regulation effect of heat traditional Chinese medicine from multi-angle system.