Fehmann H C, Janssen M, Göke B
Department of Medicine, Philipps-University, Marburg, Germany.
Acta Diabetol. 1995 Oct;32(3):176-81. doi: 10.1007/BF00838488.
The interaction of glucagon-like peptide-I (GLP-I) and galanin in clonal endocrine pancreatic cells was characterized. By Northern blot analysis the presence of GLP-I receptor mRNA was shown in B (beta TC-1 cells) and D (RIN 1048-38) cells but not in A (INR1 G9) cells, thus confirming functional data demonstrating the absence of active GLP-I receptors on glucagon-producing cells. Galanin receptors were detected on B and D cells but not on A cells. In B and D cells galanin inhibited the GLP-I stimulated adenylate cyclase activity. Treatment of insulin- and somatostatin-producing cells with GLP-I increased intracellular cAMP levels, and this was dampened by galanin, GLP-I stimulated the activity of protein kinase A in B and D cells, which was also inhibited by galanin. Galanin alone did not influence B- and D-cell function. These data show that in the endocrine pancreas B and D cells but not A cells express GLP-I and galanin receptors. The interaction of GLP-I and galanin might act in the endocrine pancreas as a physiological inhibitor of the potent incretin hormone GLP-I. Therefore, we suggest galanin is a 'decretin'.
对胰高血糖素样肽-1（GLP-1）与甘丙肽在克隆的内分泌胰腺细胞中的相互作用进行了表征。通过Northern印迹分析，在B（βTC-1细胞）和D（RIN 1048-38）细胞中显示出GLP-1受体mRNA的存在，但在A（INR1 G9）细胞中未显示，从而证实了功能数据表明在产生胰高血糖素的细胞上不存在活性GLP-1受体。在B和D细胞上检测到甘丙肽受体，但在A细胞上未检测到。在B和D细胞中，甘丙肽抑制GLP-1刺激的腺苷酸环化酶活性。用GLP-1处理产生胰岛素和生长抑素的细胞可增加细胞内cAMP水平，而甘丙肽可抑制这种增加。GLP-1刺激B和D细胞中蛋白激酶A的活性，这也受到甘丙肽的抑制。单独的甘丙肽不影响B细胞和D细胞的功能。这些数据表明，在内分泌胰腺中，B细胞和D细胞而非A细胞表达GLP-1和甘丙肽受体。GLP-1与甘丙肽的相互作用可能在内分泌胰腺中作为强效肠促胰岛素激素GLP-1的生理抑制剂起作用。因此，我们认为甘丙肽是一种“降cretin”。
