Miki H, Namba M, Nishimura T, Mineo I, Matsumura T, Miyagawa J, Nakajima H, Kuwajima M, Hanafusa T, Matsuzawa Y
Second Department of Internal Medicine, Osaka University Medical School, Japan.
Biochim Biophys Acta. 1996 Jun 13;1312(2):132-6. doi: 10.1016/0167-4889(96)00032-8.
We investigated the effect of GLPs on glucose uptake in isolated rat adipocytes. GLP-1(7-36)amide significantly enhanced glucose uptake in the presence of 1 nM insulin. GLP-1(7-36)amide at 15 nM increased glucose uptake maximally by 56.4% as compared with 1 nM insulin alone (P < 0.01). In contrast, with less than 1 nM insulin or without insulin GLP-1(7-36)amide showed no effect on glucose uptake. Full-sequence GLP-1(1-37) at 15 nM in the presence of 1 nM insulin increased glucose uptake by 24.6% as compared with 1 nM insulin alone (P < 0.05). GLP-2 showed no effect on glucose uptake. Further, we examined the effect of GLP-1(7-36)amide on cAMP content in isolated rat adipocytes. Insulin at 1 nM caused a significant decrease of cAMP content. The combination of 15 nM GLP-1(7-36)amide and 1 nM insulin caused a further reduction of cAMP content. These data indicate that GLP-1(7-36)amide possesses augmentative effects on insulin action in isolated rat adipocytes. Furthermore, it is suggested that the stimulatory effect of GLP-1(7-36)amide occurs through the reduction of intracellular cAMP content.
我们研究了胰高血糖素样肽（GLPs）对分离的大鼠脂肪细胞葡萄糖摄取的影响。在存在1 nM胰岛素的情况下，GLP-1(7-36)酰胺显著增强了葡萄糖摄取。与单独使用1 nM胰岛素相比，15 nM的GLP-1(7-36)酰胺使葡萄糖摄取最大增加了56.4%（P < 0.01）。相反，在胰岛素浓度低于1 nM或无胰岛素的情况下，GLP-1(7-36)酰胺对葡萄糖摄取无影响。在存在1 nM胰岛素的情况下，15 nM的全长序列GLP-1(1-37)与单独使用1 nM胰岛素相比，使葡萄糖摄取增加了24.6%（P < 0.05）。GLP-2对葡萄糖摄取无影响。此外，我们检测了GLP-1(7-36)酰胺对分离的大鼠脂肪细胞中环磷酸腺苷（cAMP）含量的影响。1 nM胰岛素导致cAMP含量显著降低。15 nM GLP-1(7-36)酰胺与1 nM胰岛素联合使用导致cAMP含量进一步降低。这些数据表明，GLP-1(7-36)酰胺对分离的大鼠脂肪细胞中的胰岛素作用具有增强作用。此外，可以推测GLP-1(7-36)酰胺的刺激作用是通过降低细胞内cAMP含量实现的。
