【摘要】 目的研究不同锌营养状况对大鼠铁代谢和肝脏铁调节蛋白(IRP)mRNA、铁蛋白(Fn)mRNA及转铁蛋白受体(TfR)mRNA的影响。方法 40只雄性SD大鼠按体重随机分为4组,每组10只,铁和锌正常对照组(ZA组),铁正常锌缺乏组(ZD组),铁和锌正常配饲组(PF组),铁正常锌过量组(ZE组)。喂饲8周后麻醉处死,取大鼠肝脏、脾脏和血清,测定血红蛋白,血清锌、血清铁、血清转铁蛋白受体、血清铁蛋白、肝脏铁和锌含量、脾脏铁和锌含量,并用逆转录-聚合酶链反应(RT-PCR)法检测各组大鼠IRP2 mRNA和肝脏TfR mRNA以及Fn mRNA的表达水平。结果与对照组相比,锌过量使肝脏和脾脏铁含量、血清铁水平显著降低(P<0.05);锌缺乏使肝脏铁含量、血清转铁蛋白受体水平显著增高(P<0.05),同时,血清铁水平显著降低(P<0.05);锌缺乏时肝脏IRP mRNA及TfR mRNA表达显著增强。结论锌缺乏可能通过影响铁吸收、储存、转运来影响体内铁的营养状况。锌缺乏通过改变IRP2表达、IRP-RNA结合活性,在转录后水平改变TfR mRNA和FnmRNA表达,影响铁稳态。更多还原

【Abstract】 Objective To study the effects of different zinc nutritional status on iron metabolism and explore the potential role of iron regulator protein 2(IRP2) under conditions of zinc deficiency.Methods Forty clean male SD rats were randomly divided into four groups according to the weight and every group included 10 rats.The rats were administrated normal iron and zinc control group(ZA group),normal iron and slight deficient group(ZD group),Paired fed group(PF group),normal iron and zinc excessive group(ZE group).Rats were sacrificed by sodium pentobarbital anesthesia after 8 weeks and serum,liver and spleen of the rats were collected.The serum zinc,serum iron,hemoglobin,serum transferrin receptor,serum ferritin,iron and zinc in the liver,iron and zinc in the spleen were determined.The level of IRP2 mRNA expression,liver transferring receptor(TfR)mRNA expression and ferritin(Fn) mRNA expression were measured using reverse transcription polymerase chain reaction(RT-PCR) method.Results Compared with that of the control group,iron content both in the liver and spleen,and the concentration of serum iron in ZE group was significantly decreased(P<0.05).Compared with the control group,zinc deficiency increased iron content in the liver and the concentration of serum transferrin receptor significantly(P<0.05),while the concentration of serum iron was significantly decreased(P<0.05).Compared with the control group,zinc deficiency increased the level of IRP2 mRNA and TfR mRNA expression in the liver significantly(P<0.05).Conclusion Zinc may affect iron nutritional status by influencing absorption,storage and transportation of iron.Zinc deficiency influences iron homeostasis in cells through affecting the expression of IRP2 and the activity of IRP-RNA combination and then change the expressions of ferritin and transferrin mRNA.更多还原