年龄对大鼠肝细胞胰岛素受体的影响

Effects of age on insulin receptors in rat hepatocytes

目的 研究年龄对大鼠肝细胞胰岛素受体的影响 ,探讨衰老肝细胞胰岛素受体改变的意义和胰岛素抵抗的机理。方法 2 0只大鼠分为青年组和老年组 ,用放免法和放射性配体-配体测定法分别测定其血浆胰岛素和肝细胞胰岛素受体。结果 老年大鼠血浆胰岛素浓度较青年大鼠显著升高 (P <0 .0 5 ) ,肝细胞高亲和力受体数目较青年大鼠明显下降 (P <0 .0 5 ) ,两组间低亲和力受体数目和亲和力无明显变化 (P >0 .0 5 )。结论 大鼠肝细胞高亲和力胰岛素受体数目在老年期下降 ,老年大鼠存在有胰岛素抵抗。

Objective To observe the effects of age on insulin receptors (IR) in isolated rat liver cells, and to study the significance of the changes of IR in aging cells and the probable mechanism of the insulin resistance.Methods Twenty rats were divided into the young and the old groups, and their plasma insulin and IR on hepatocytes were measured by radioimmunoassay and radioreceptor-ligand assay respectively.Results Compared with young rats, the concentration of the insulin in plasma increased markedly in old group. However, the number of the high affinity receptors on the hepatocytes was found to be decreased significantly in aging rats. There was no significant difference of the number of the low affinity sites or affinity between the young and the old rats.Conclusion The findings suggest that the number of high affinity IR on hepatocytes will decrease with the developing of senescence, and there is the insulin resistance in aging rats.