Ishibashi F, Sato T, Onari K, Tsubota M, Kawate R
Metabolism. 1980 Jul;29(7):682-5. doi: 10.1016/0026-0495(80)90114-6.
A detailed dose-response study relating mannose and glucose oxidation with the induction of 45Ca uptake and insulin release was performed using in vitro incubation of collagenase digested rat islets of Langerhans. The threshold value for 14C-U-D-glucose oxidation, glucose-stimulation of 45Ca uptake, and insulin release was about 5.5 mM. The half maximal response for these 3 parameters occurred at 13.4 mM, 11.6 mM, and 12.2 mM, respectively. Their maximal responses were obtained at approximately 20 mM. The threshold level for mannose oxidation, induction of 45Ca uptake and insulin release was about 11.0 mM, with half maximal responses obtained at 24.6 mM, 20.5 mM, and 22.2 mM, respectively. The maximum response of the 3 parameters to mannose was obtained at 38.8 mM and appeared to reach the same level obtained for glucose. These results suggest that hexose degradation has a significant role in controlling Ca uptake and subsequent insulin release. A lower rate of mannose oxidation appeared to account for its weaker stimulating efficacy for Ca uptake and insulin release.
利用胶原酶消化的大鼠胰岛进行体外孵育，开展了一项关于甘露糖和葡萄糖氧化与诱导45Ca摄取及胰岛素释放之间关系的详细剂量反应研究。14C-U-D-葡萄糖氧化、葡萄糖刺激45Ca摄取以及胰岛素释放的阈值约为5.5 mM。这三个参数的半数最大反应分别出现在13.4 mM、11.6 mM和12.2 mM。它们的最大反应在约20 mM时获得。甘露糖氧化、诱导45Ca摄取和胰岛素释放的阈值约为11.0 mM，半数最大反应分别在24.6 mM、20.5 mM和22.2 mM时获得。这三个参数对甘露糖的最大反应在38.8 mM时获得，且似乎达到了与葡萄糖相同的水平。这些结果表明，己糖降解在控制钙摄取及随后的胰岛素释放中具有重要作用。甘露糖氧化速率较低似乎是其对钙摄取和胰岛素释放刺激效果较弱的原因。
