饥饿与再投喂对鳊鱼幼鱼糖代谢的影响

Effects of Starvation and Refeeding on Metabolism of Glucose in Juvenile Parabramis pekinensis

在(20±1)℃条件下测定短期饥饿和再投喂不同时间后鳊鱼(Parabramis pekinensis)幼鱼肝指数、肝糖原含量和血糖浓度的变化;以正常持续喂食实验鱼作为对照组,分别在饥饿处理0、1、4、7、12d后以及饥饿12d再恢复投喂1、4、7、15d后取样。结果显示,实验鱼随饥饿时间的延长,肝指数和肝糖原含量均呈显著下降趋势(p<0.05),饥饿4d后分别为(1.34±0.05)、(10.53±4.18)mg·g-1,均显著低于初始水平(p<0.05),饥饿12d后分别为(0.96±0.04)、(4.03±0.81)mg·g-1达到最低水平(p<0.05);再投喂后,上述两个指标均呈显著上升趋势(p<0.05),再投喂1d后的肝糖原和15d后的肝指数分别恢复至初始水平(p>0.05)。实验鱼在饥饿处理和恢复投喂的过程中,与对照组比较血糖浓度没有出现显著差异。结果表明,鳊鱼幼鱼在饥饿和恢复投喂的过程中,血糖浓度表现出较好的稳定性,而肝糖原含量变化速度快于和肝指数。由此推测鳊鱼幼鱼在饥饿过程中主要利用糖类来提供能量,且首先动用肝脏内的储能物质,肝糖原含量的变动与血糖浓度的稳定性有直接关联。

The effects of short-term starvation and refeeding with different time courses on hepatosomatic index（HSI） ,liver glycogen and serum glucose in juvenile Parabramis pekinensis is investigated.The fish were randomly allocated into control and treatment groups （20 ±1） ℃,control group was sustained fed,treatment groups were starved for 0,1,4,7,12 d or starved for 12 d then refed for 1,4,7,15 d respectively.Samples were taken after the process.The result showed that,as starvation continued,HSI and liver glycogen decreased significantly （p 0.05） .Fasting for 4 days,the two indices were （1.34 ± 0.05） and （10.53 ± 4.18） mg·g^-1,and been both markedly below original value;when starved for 12 days,the two indices were （0.96 ± 0.04） and （4.03 ± 0.81） mg·g^-1,which were the lowest value,respectively.As refeeding continued,HSI and liver glycogen increased significantly （p〈0.05） .The value of liver glycogen after refeeding for 1 d and 15 d had returned to those of original level （p〉0.05） .During the experiment,serum glucose took on a similar trend with HSI and liver glycogen,and it had a less variation extent.The results indicated that serum glucose had a better stability than the other two indices;moreover,liver glycogen recovered faster than HSI.So,we suggest that during the starvation,the fish mainly uses glucide as energy source,mobilizes the substance in liver firstly and the change of liver glycogen has a direct relationship with the stability of serum sugar.