克伦特罗对大鼠肝脏氮代谢及IGF-I水平的影响  

EFFECTS OF CLENBUTEROL ON THE METABOLISM OF NITROGEN AND IGF-I LEVEL IN ISOLATED PERFUSED RAT LIVER

作　　者：郑元林[1] 韩正康[2] 陈杰[2] 刘根桃[2] 

机构地区：[1]徐州师范大学生物系,江苏徐州221009 [2]南京农业大学农业部动物生理生化重点开放实验室,江苏南京210095

出　　处：《中国应用生理学杂志》2002年第2期169-172,共4页Chinese Journal of Applied Physiology

基　　金：国家自然科学基金资助项目 (3 95 70 5 3 6)

摘　　要：目的 :探讨克伦特罗 (CL)影响机体物质代谢的有关肝脏机制。方法 :利用大鼠离体肝脏灌流技术测定CL对肝脏灌流液中尿素氮水平 ,肝组织谷丙转氨酶 (GPT)活性以及肝脏胰岛素样生长因子I(IGF I)合成和分泌的影响。结果 :CL可使大鼠离体肝脏产生的尿素氮浓度下降 ,并有一定的剂量效应和时间效应。在给药后灌流的 1、2、3、4h内 1× 10 -6mol/L的CL使大鼠肝脏产生的尿素氮分别下降 15 .0 2 % (P >0 .0 5 )、17.97% (P >0 .0 5 )、2 6 .76 % (P <0 .0 5 )和 30 .0 8% (P <0 .0 1) ,1× 10 -8mol/L的CL具有类似的效应。CL抑制大鼠肝组织中GPT的活性 ,1× 10 -6mol/L的CL使得肝组织中GPT活性下降 2 4 .6 5 % (P <0 .0 5 )。CL还影响大鼠离体肝脏IGF I的生成和分泌 ,1× 10 -6mol/LCL使大鼠肝组织内IGF I的含量比对照组升高 19.77% (P <0 .0 5 ) ,灌流液中IGF I的水平也呈增加的趋势。结论 :CL可通过增加对肝脏氮的储留及增强肝脏IGF 1的合成和分泌而促进机体的物质代谢。Aim:To examine the liver mechanism with which clenbuterol is explained how to affect growth metabolism.Methods:Twenty four adult SD rats were randomly divided into three groups, a control and two treatment groups. The technique of isolated perfused rat liver in vitro was used to study the effects of clenbuterol on urea nitrogen concentration of perfused medium, GPT activity and synthesis and secretion of IGF I in isolated perfused rat liver.Results: Urea nitrogen concentration of perfused medium was significantly affected by clenbuterol in a dose dependent and time dependent manner. The urea nitrogen level was decreased by 15.02% ( P >0.05),17.97% ( P >0.05),26.76% ( P < 0.05 ) and 30.08% ( P <0.01) for 1 h, 2 h, 3 h, 4 h after administering clenbuterol at the dose of 1×10 -6 mol/L, respectively, compared to that of control. 1×10 -8 mol/L CL had the similar effect on urea nitrogen level. GTP activity of isolated perfused rat liver was inhibited by clenbuterol. The enzyme activity was decreased by 24.65% ( P < 0.05 ) at the dose of 1 10 -6 mol/L CL in clenbuterol treated 4h. The production and secretion of IGF I were also influenced by clenbuterol in isolated perfused rat liver. IGF I concentration of rat liver was increased by 19.77% ( P < 0.05 ) in 4 h clenbuterol treatment (1×10 -6 mol/L). Meanwhile, IGF I concentration of perfusion medium was also elevated though the difference was not significant compared with control. Conclusion: It is suggested that clenbuterol may improve growth metabolism by means of increasing nitrogen retention and enhancing IGF I production and secretion of rat liver.

关 键 词：克伦特罗 大鼠 肝脏 氮代谢 IGF-I 动物 肌肉增重 体脂下降 

分 类 号：S816.7[农业科学—饲料科学] S859.794[农业科学—畜牧学]