Janciauskiene S, Eriksson S, Carlemalm E, Ahrén B
Department of Medicine, Lund University, Malmö, Sweden.
Biochem Biophys Res Commun. 1997 Jul 30;236(3):580-5. doi: 10.1006/bbrc.1997.7014.
Islet amyloid polypeptide (IAPP) forms fibrils spontaneously. We examined whether other B cell granule peptides affect formation of beta-pleated sheet fibrils in vitro from human IAPP. Quantitative radioassay (radioactivity of soluble IAPP after adding 125I-IAPP) and thioflavine fluorescence spectroscopy showed that insulin, C-peptide, and pancreastatin inhibited fibril formation by 60-100% at ratio 100:1 (peptide:IAPP), whereas at 1:10 or 1:100, i.e., IAPP in excess, a potentiated IAPP fibril formation was induced by the peptides. Semi-quantitative analysis by electron microscopy yielded similar effects. Thus, spontaneous IAPP fibrillisation is influenced by other B cell secretory granule peptides in a molar ratio dependent manner.
胰岛淀粉样多肽（IAPP）可自发形成纤维。我们研究了其他B细胞颗粒肽是否会在体外影响人IAPP形成β-折叠片层纤维。定量放射测定法（添加125I-IAPP后可溶性IAPP的放射性）和硫黄素荧光光谱显示，胰岛素、C肽和胰抑制素在100:1（肽：IAPP）的比例下可抑制纤维形成60 - 100%，而在1:10或1:100，即IAPP过量的情况下，这些肽会诱导IAPP纤维形成增强。通过电子显微镜进行的半定量分析也得出了类似的结果。因此，IAPP的自发纤维化受到其他B细胞分泌颗粒肽的影响，且这种影响具有摩尔比依赖性。
