Hayashi K
Gerontology. 1982;28(1):10-8. doi: 10.1159/000212506.
Insulin and glucagon secretion after glucose load and the hormone-receptor inter-action were compared between 6- and 24-month-old Wistar rats. The 24-month-old rats showed a failure to decrease glucagon secretion after glucose load in contrast to 6-month-old rats with a similar degree of glucose tolerance and insulin response. Age-related change of insulin receptor of rat livers was tentatively suggested to be a disappearance of the binding site with higher affinity. Affinity of the glucagon receptor did not differ significantly between the two groups. The hyposuppressibility of glucagon by hyperglycemia and the decrease of insulin affinity might contribute to the glucose intolerance with aging.
比较了6月龄和24月龄Wistar大鼠葡萄糖负荷后胰岛素和胰高血糖素的分泌情况以及激素与受体的相互作用。与具有相似葡萄糖耐量和胰岛素反应程度的6月龄大鼠相比，24月龄大鼠在葡萄糖负荷后胰高血糖素分泌未能减少。初步认为大鼠肝脏胰岛素受体的年龄相关变化是高亲和力结合位点的消失。两组之间胰高血糖素受体的亲和力没有显著差异。高血糖对胰高血糖素抑制作用减弱以及胰岛素亲和力降低可能导致衰老过程中的葡萄糖不耐受。
