静脉注射^(53)Cr标记吡啶甲酸铬对仔猪脂质和DNA氧化的影响

EFFECT OF ITRAVENOUS INJECTIOU OF ^(53)Cr-CHROMIUM PICOLINATE ON PIGLET LIPID AND DNA PEROXIDATION

选取体重15.0kg±1.0kg、健康的瘦肉型三元杂交(杜×长×大)仔猪30头,按体重、遗传背景相近的原则随机分成5组,每组6头,单笼个体饲养。每天上午08:00-10:00分别对各组猪进行静脉注射,Ⅰ(对照)、Ⅱ、Ⅲ、Ⅳ、Ⅴ组分别注射0、8、200、400和800μg Cr/d的53Cr标记吡啶甲酸铬,试验期14d。检测指标为肝肾中示踪剂铬、抗氧化酶和丙二醛(MDA)、尿中8-羟基脱氧鸟苷(8-OHdG)。研究表明,吡啶甲酸铬在肝、肾中的蓄积量随着静脉注射吡啶甲酸铬水平的升高而增加,且剂量在200μg以上达到显著(P<0.05);与对照组相比,仔猪的血清、肝、肾中MDA都无显著变化(P>0.05);除血清SOD和肾脏CAT活性显著下降(P<0.05)外,其他抗氧化酶活性也无显著变化(P>0.05)。但肾脏中,800μg组MDA水平显著高于8μg组(P<0.05)。尿液中8-羟基脱氧鸟苷的水平未发生显著变化。结果显示,在本试验剂量范围内(800μgCr/d,14d),吡啶甲酸铬在仔猪肝脏、肾脏内显著沉积,肾脏中沉积量高于肝脏;肾脏脂质过氧化与肾中铬浓度之间存在显著量效关系;静脉注射不同水平吡啶甲酸铬未引起机体DNA氧化损伤和肝脏脂质过氧化。

Thirty 15kg±1kg body weight male crossbred（D×L×Y） piglets were divided into five groups with six replication each treatment,each piglet was raised in one cage.During 14 days experimental period,piglets of 5 groups were injected with 0,8,200,400,800μg Cr/d[^53CrPic3] at 08：00-10：00 every morning respectively.The contents of tracer chromium in liver and kidney,antioxidant enzymes activity,lipid peroxides and the level of 8-OHdG in urine were measured.Results showed that the contents of chromium in liver and kidney were increased with the increase of CrPic3.Compared to control,the concentration of chromium was remarkably higher being injected more than 200μg Cr（P〈0.05）.In comparison with control,the levels of MDA in serum,liver and kidney did not increase significantly（P〉0.05）.The antioxidant enzymes activity had no significant differences,except the decrease of SOD activity in serum and CAT activity in kidney.But compared to 8μg group,the renal MDA content in 800μg group markedly increased（P〈0.05）.About the level of 8-OHdG in urine,no significance was detected among all groups（P〉0.05）.Take together,Chromium picolinate accumulate remarkably in liver and kidney of piglet,Cr accumulation in kidney is significantly higher than that in liver.There is a significant dose-effect relationship between renal lipid peroxidation and the renal Cr content.Chromium picolinate accumulate remarkably in liver and kidney of piglet,increases in tissue Cr is higher in kidney than in liver.Chromium picolinate below 800μg Cr /d injected in vein for 14 days,does not induce DNA and hepatic lipid peroxidation.