Chertow B S, Baker G R
Endocrinology. 1978 Nov;103(5):1562-72. doi: 10.1210/endo-103-5-1562.
We tested the effects of vitamin A, a membrane surface-active agent, on glucose (16.7 mM)-induced biphasic insulin release from collagenase-isolated rat islets. Also, efforts were made to correlate the effects of vitamin A with glucose oxidation. Vitamin A (10(-4) M) inhibited first- and second phase insulin release; 10(-5) M vitamin A inhibited second phase release only and to a lesser extent than that observed with 10(-4) M vitamin A; and 10(-6) M vitamin A had no effect. Vitamin A (10(-7) M) stimulated biphasic insulin release. Exposure to high glucose (27.8 mM) overcame the effects of 10(-4) M vitamin A on first phase release, but not on second phase release of insulin. Exposure to 10(-5) M hydrocortisone opposed the effects of 10(-4) M vitamin A on both phases of insulin release. Vitamin A (10(-4) and 10(-5) M) inhibited glucose oxidation by islets, as measured by the production of 14CO2 from [14C]glucose. The effects of vitamin A on insulin release were dissociated in part from those effects on glucose oxidation, in that hydrocortisone opposed the effect of vitamin A on insulin release but not on glucose oxidation. The effects of vitamin A on insulin secretion can best be explained by the interaction of vitamin A at multiple sites affecting the membrane and intracellular glucose oxidation.
我们测试了膜表面活性剂维生素A对胶原酶分离的大鼠胰岛由葡萄糖（16.7 mM）诱导的双相胰岛素释放的影响。此外，还努力将维生素A的作用与葡萄糖氧化联系起来。维生素A（10^(-4) M）抑制第一相和第二相胰岛素释放；10^(-5) M维生素A仅抑制第二相释放，且抑制程度小于10^(-4) M维生素A；而10^(-6) M维生素A无作用。维生素A（10^(-7) M）刺激双相胰岛素释放。暴露于高葡萄糖（27.8 mM）可克服10^(-4) M维生素A对胰岛素第一相释放的影响，但不能克服对第二相释放的影响。暴露于10^(-5) M氢化可的松可对抗10^(-4) M维生素A对胰岛素释放两个阶段的影响。如通过[14C]葡萄糖产生14CO2所测量的，维生素A（10^(-4)和10^(-5) M）抑制胰岛的葡萄糖氧化。维生素A对胰岛素释放的作用部分与对葡萄糖氧化的作用分离，因为氢化可的松对抗维生素A对胰岛素释放的作用，但不影响葡萄糖氧化。维生素A对胰岛素分泌的作用最好通过维生素A在多个影响膜和细胞内葡萄糖氧化的位点的相互作用来解释。
