King D L, Chick W L
Endocrinology. 1976 Oct;99(4):1003-9. doi: 10.1210/endo-99-4-1003.
Neonatal rat pancreatic monolayer cultures were utilized to investigate the effects of various hexose sugars on insulin release and beta cell replication. Sugars tested were D-glucose, L-glucose, 3-O-methyl-D-glucose, D-mannose and D-fructose. These agents were added at varying concentrations to a control medium containing a baseline level of 5.5 mM D-glucose. Replication was estimated by incubating cultures with [3H]thymidine and determining the frequency of beta cell labelling in aldehyde-thionin stained radioautographs. Although the addition of D-glucose to the control medium resulted in a concentration-dependent increase in both insulin release and beta cell replication, the sensitivity of these two processes to glucose differed. Insulin release was stimulated by a 2.75 mM elevation in the D-glucose concentration of the control medium, while an elevation of 11 mM D-glucose was required to increase the frequency of beta cell replication. Moreover, while insulin release was maximally stimulated by an 11 mM elevation in the concentration of D-glucose, the frequency of replication continued to rise as the concentration of D-glucose was further increased. The specificity of these responses to D-glucose was demonstrated by the inability of 11 mM L-glucose or 11 mM 3-O-methyl-D-glucose to stimulate beta cell replication. D-mannose and D-fructose were less potent insulin secretagogues than D-glucose on an equimolar basis and neither compound enhanced beta cell replication at a concentration of 11 mM. However, higher concentrations of D-mannose (16.5 and 22 mM) enhanced beta cell replication, while comparable concentrations of D-fructose did not. These results indicate that the sensitivity of insulin release and beta cell replication to D-glucose differ, and that in addition to D-glucose, D-mannose is also capable of stimulating beta cell replication.
利用新生大鼠胰腺单层培养物来研究各种己糖对胰岛素释放和β细胞复制的影响。所测试的糖类有D-葡萄糖、L-葡萄糖、3-O-甲基-D-葡萄糖、D-甘露糖和D-果糖。将这些试剂以不同浓度添加到含有5.5 mM D-葡萄糖基线水平的对照培养基中。通过用[3H]胸腺嘧啶核苷孵育培养物并在醛-硫堇染色的放射自显影片中确定β细胞标记频率来估计复制情况。尽管向对照培养基中添加D-葡萄糖导致胰岛素释放和β细胞复制均呈浓度依赖性增加，但这两个过程对葡萄糖的敏感性不同。对照培养基中D-葡萄糖浓度升高2.75 mM可刺激胰岛素释放，而需要升高11 mM D-葡萄糖才能增加β细胞复制频率。此外，虽然胰岛素释放受到D-葡萄糖浓度升高11 mM的最大刺激，但随着D-葡萄糖浓度进一步增加，复制频率持续上升。11 mM L-葡萄糖或11 mM 3-O-甲基-D-葡萄糖无法刺激β细胞复制，这证明了这些对D-葡萄糖反应的特异性。在等摩尔基础上，D-甘露糖和D-果糖作为胰岛素促分泌剂的效力低于D-葡萄糖，且在11 mM浓度下这两种化合物均未增强β细胞复制。然而，较高浓度的D-甘露糖（16.5和22 mM）增强了β细胞复制，而相当浓度的D-果糖则没有。这些结果表明，胰岛素释放和β细胞复制对D-葡萄糖的敏感性不同，并且除了D-葡萄糖外，D-甘露糖也能够刺激β细胞复制。
