Pancreatic beta cell replication: effects of hexose sugars.
Pancreatic beta cell replication: effects of hexose sugars.
复制标题
胰腺β细胞复制：己糖的影响。
DOI：
10.1210/endo-99-4-1003
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发表时间：
1976
期刊：
影响因子：
4.8
通讯作者：
W. Chick
中科院分区：
文献类型：
--
作者：
D. L. King;W. Chick
采用新生大鼠胰腺单层培养，观察不同己糖对胰岛素释放和胰岛β细胞复制的影响。测定的糖有D-葡萄糖、L-葡萄糖、3-O-甲基-D-葡萄糖、D-甘露糖和D-果糖。这些试剂以不同的浓度加入到基线水平为5.5 mM D-葡萄糖的对照培养液中。通过与[~3H]胸腺嘧啶核苷孵育和测定乙醛-硫胺素染色放射自显影中的β细胞标记频率来估计复制情况。尽管在对照培养液中添加D-葡萄糖导致胰岛素释放和β细胞复制的浓度依赖性增加，但这两个过程对葡萄糖的敏感性不同。对照培养液中D-葡萄糖浓度升高2.75 mM可刺激胰岛素释放，而D-葡萄糖浓度升高11 mM则需要增加β细胞复制频率。此外，当D-葡萄糖浓度升高11 mm时，胰岛素的释放得到最大刺激，复制频率随着D-葡萄糖浓度的进一步增加而继续上升。11 mM L葡萄糖或11 mM 3-O-甲基-D-葡萄糖不能刺激β细胞复制，证明了这些反应对D-葡萄糖的特异性。在等摩尔基础上，D-甘露糖和D-果糖是比D-葡萄糖更弱的胰岛素促分泌剂，而且在浓度为11 mM时，两种化合物都不能促进β细胞的复制。然而，较高浓度的D-甘露糖(16.5和22 mM)促进了β细胞的复制，而同等浓度的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，除了D-葡萄糖外，D-甘露糖还能够刺激β细胞复制。
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.