Sgambato S, Passariello N, Paolisso G, Marano A, Buoninconti R, Tesauro P
Acta Diabetol Lat. 1986 Jan-Mar;23(1):13-22. doi: 10.1007/BF02581349.
Many studies have shown that in normal man salmon and porcine CT administration in bolus inhibits the release of TSH, LH, GH, and glucose- or arginine-induced insulin secretion. In the present study we investigated the effects of human synthetic calcitonin (hCT) on glucose- or arginine-induced insulin secretion in man. Twenty-two subjects were submitted to i.v. administration of hCT during glucose or arginine test. In our opinion, the most interesting results are those observed with arginine plus hCT at two different dosages (25 micrograms and 12.5 micrograms infused in 30 min). In fact arginine plus hCT (25 micrograms in 30 min) administration induced a significant increase of glycemia at 5, 10 and 20 min (p less than 0.01) and at 30 min (p less than 0.05) and a significant decrease of IRI at 5, 10, 20 and 30 min (p less than 0.001) and at 45 min (p less than 0.005). The highest plasma CT levels were observed at 15 and 30 min (490 and 540 pg X ml-1). Arginine plus hCT (12.5 micrograms in 30 min) infusion induced a similar significant increase in plasma glucose at 10, and 20 min (p less than 0.05) and at 30 min (p less than 0.01) and a significant decrease of plasma IRI at 10 min (p less than 0.05) at 20 min and 30 min (p less than 0.005). The highest plasma CT levels were reached at 20 min and 30 min (250 and 270 pg X ml-1, respectively). Our results clearly demonstrate that physiologic doses of hCT are able to inhibit arginine induced insulin secretion in normal man. Since insulin induces hypercalcemia and food ingestion increases both insulin and CT, one could hypothesize that CT inhibits insulin secretion thus controlling post-prandial hypercalcemia by its osteotrophic effect and by its action upon calcium redistributed within the cells.
许多研究表明，在正常人体内，静脉推注鲑鱼降钙素和猪降钙素会抑制促甲状腺激素、促黄体生成素、生长激素以及葡萄糖或精氨酸诱导的胰岛素分泌。在本研究中，我们调查了人合成降钙素（hCT）对人体葡萄糖或精氨酸诱导的胰岛素分泌的影响。22名受试者在葡萄糖或精氨酸测试期间接受了静脉注射hCT。在我们看来，最有趣的结果是在精氨酸加两种不同剂量（30分钟内分别注入25微克和12.5微克）的hCT时观察到的。事实上，注射精氨酸加hCT（30分钟内25微克）后，在5、10和20分钟时血糖显著升高（p<0.01），30分钟时血糖也显著升高（p<0.05），而在5、10、20和30分钟以及45分钟时胰岛素释放指数（IRI）显著降低（p<0.001和p<0.005）。在15和30分钟时观察到血浆CT水平最高（分别为490和540 pg·ml⁻¹）。注射精氨酸加hCT（30分钟内12.5微克）后，在10和20分钟以及30分钟时血浆葡萄糖也有类似的显著升高（p<0.05和p<0.01），在10分钟时血浆IRI显著降低（p<0.05），在20和30分钟时也显著降低（p<0.005）。在20和30分钟时达到最高血浆CT水平（分别为250和270 pg·ml⁻¹）。我们的结果清楚地表明，生理剂量的hCT能够抑制正常人精氨酸诱导的胰岛素分泌。由于胰岛素会导致高钙血症，而食物摄入会增加胰岛素和CT，因此可以推测CT通过其对骨的营养作用以及对细胞内钙再分布的作用来抑制胰岛素分泌，从而控制餐后高钙血症。
