不同剂量脂肪膜抗体对大鼠脂肪沉积的影响及其机制  

Effects of Different Dosage of Yolk Antibodies against Adipocyte Plasma Membranes on Fat Deposition in Rats and Its Possible Mechanisms

作　　者：周杰[1,2] 赵茹茜[2] 陈杰[2] 陈永秦 

机构地区：[1]安徽农业大学动物科技学院,合肥230036 [2]南京农业大学农业部动物生理生化重点开放实验室,南京210095 [3]上海华扩达生化科技有限公司,上海201206

出　　处：《农业生物技术学报》2011年第1期18-25,共8页Journal of Agricultural Biotechnology

基　　金：国家自然基金重点项目(No.39830290);上海华扩达生化科技有限公司委托项目资助

摘　　要：过多的脂肪沉积影响肉的品质。(110±10)g雌性(♀)SD大鼠(Rattus norvegicus)150只,随机分成5组,分别在基础日粮中添加0、75、500、1000和6000mg/kg含脂肪细胞膜卵黄抗体的阳性卵黄粉。75d屠宰,采集血样、肠系膜脂、子宫周脂、肾脂肪囊和下丘脑。放射免疫法测定血清Insulin和Leptin浓度。用RT-PCR方法,以18S rRNA作内标分析不同部位脂肪组织中Leptin、Bcl-2和Bax mRNA和下丘脑Ob基因b型受体(Ob-Rb)mRNA表达,并测定各部位脂肪组织DNA和RNA含量。结果显示,卵黄抗体处理可降低大鼠腹腔内总脂重和腹腔内总脂指数,其中75和6000mg/kg阳性卵黄粉组效果明显,但对体重、摄食量和腓肠肌重无显著影响。6000mg/kg阳性卵黄粉组可降低血清甘油三酯,升高血清游离脂肪酸;降低子宫周脂和肾脂肪囊DNA含量和总量。75mg/kg阳性卵黄粉组可降低子宫周脂和肾脂肪囊DNA总量;两剂量组均可降低血清胰岛素、子宫周脂和肾脂肪囊Leptin mRNA表达,上调下丘脑Ob-Rb mRNA表达;降低子宫周脂Bcl-2mRNA和Bax mRNA表达,但对Bcl-2/Bax无显著影响。不同部位比较发现,Leptin mRNA表达量为肾脂肪囊>子宫周脂>肠系膜脂(P<0.01);Bcl-2和Bax mRNA表达量为子宫周脂和肾脂肪囊显著高于肠系膜脂(P<0.05)。结果提示:口服脂肪细胞膜卵黄抗体降低体脂沉积的作用途径可能是:1)直接溶解脂肪细胞,抑制脂肪细胞增殖;2)通过脂肪代谢的改变,间接减少脂肪沉积。Excess fat deposition in livestock is of major concern to the meat industry. Various approaches have been attempted to solve this excessive fat deposition problem. In this paper,150 female（♀） SD rats（Rattus norvegicus） weighting （110±10） g were allotted randomly into five groups （basic diet adding 0,75,500,1 000 and 6 000 mg/kg of yolk powder containing antibody against adipocyte plasma membranes（APM）,respectively. The trial lasted for 75 days after rats were slaughtered for carcass analysis and blood,and three different white adipose tissue depots （mesenteric fat,parametrial fat and perirenal fat） and hypothalamus were sampled. Concentrations of serum insulin and serum leptin were determined by radioimmunoassay （RIA）. The total RNA was extracted from tissues to measure the abundance of Leptin,Bcl-2 and Bax mRNA in different adipose tissue depots and Ob-Rb mRNA in hypothalamus by RT-PCR with 18S rRNA internal standard. DNA and RNA content in different adipose tissue depots were determined. The results showed that yolk antibody treatment decreased celiac fat weight and index,but did no affect body weight gain,food intake of rats and gastrocnemius muscle weight. Basic diet adding 6000 mg/kg positive yolk powder decreased serum triglycerides concentration,increased serum free fatty acids （FFA） concentrations,reduced DNA content and concentration of parametrial fat and perirenal fat. Basic diet adding 75 mg/kg positive yolk powder reduced DNA content of parametrial fat and perirenal fat. Yolk antibody treatment decreased serum insulin,down-regulated Leptin mRNA expression in parametrial fat and perirenal fat,up-regulated Ob-Rb mRNA expression in hypothalamus,decreased Bcl-2 and Bax mRNA expression in parametrial fat,but did no affect Bcl-2 mRNA /Bax mRNA. The results also showed that the expression of Leptin mRNA in perirenal fat was higher than that in parametrial fat,latter was higher than that in mesenteric fat,and Bcl-2 and Bax gene expressions in parametrial and perirenal fat wer

关 键 词：脂肪细胞膜 卵黄抗体 大鼠 脂肪沉积 细胞凋亡 

分 类 号：S852.4[农业科学—基础兽医学]