Leclercq-Meyer V, Marchand J, Malaisse W J
Diabetes. 1978 Oct;27(10):996-1004. doi: 10.2337/diab.27.10.996.
The role of calcium transport into the pancreatic A2-cell in release of glucagon was studied in the perfused in vitro rat pancreas exposed to the organic calcium-antagonist verapamil (10 and 20 microns). As judged by the inhibitory effect of verapamil, a sufficient influx of calcium was required for glucagon release to be stimulated by either arginine (10 mM) or a lowering of the glucose concentration from 16.6 to 3.3 mM. However, such was not the case for glucose to inhibit the release of glucagon or when the A-2-cell was established in a stimulated state during prolonged exposure to a low, 3.3 mM, glucose concentration. These findings suggest that the role of inwardly directed transport of calcium in the secretory process of the A2-cell is of a complex nature, being dependent on the type of stimulus employed (arginine or glucose) and, in the case of glucose, on the static or dynamic state of the cell. The intimate mechanisms by which calcium exerts such complex effects on the secretory process in the A2-cell remain to be elucidated.
在体外灌注的大鼠胰腺中，研究了钙转运进入胰腺A2细胞在胰高血糖素释放中的作用，该胰腺暴露于有机钙拮抗剂维拉帕米（10和20微摩尔）。根据维拉帕米的抑制作用判断，无论是精氨酸（10毫摩尔）刺激胰高血糖素释放，还是将葡萄糖浓度从16.6毫摩尔降至3.3毫摩尔，都需要足够的钙流入。然而，当葡萄糖抑制胰高血糖素释放时，或者当A2细胞在长时间暴露于低浓度（3.3毫摩尔）葡萄糖期间处于刺激状态时，情况并非如此。这些发现表明，钙向内转运在A2细胞分泌过程中的作用具有复杂的性质，这取决于所采用的刺激类型（精氨酸或葡萄糖），对于葡萄糖而言，还取决于细胞的静态或动态状态。钙对A2细胞分泌过程产生这种复杂影响的具体机制仍有待阐明。
