Verspohl E J, Ammon H P
Horm Metab Res. 1982 Sep;14(9):464-8. doi: 10.1055/s-2007-1019048.
Binding sites of isolated rat pancreatic islets have been shown to interact with insulin. Employing various species-insulins, insulin analogues and substances not being structurally related to insulin, structure-specificity as well as pH- and temperature-dependence of insulin binding to rat pancreatic islets have been studied. Rat insulin displaced 125 I-insulin from its binding sites in the same concentration-dependent manner as pork insulin did, whereas the insulin analogue des-(phe-val-asp)B1-3-p-glu B4-insulin was less effective. Pork C-peptide hardly competed for binding and pork proinsulin did not compete at all. Both the species' insulins inhibited glucose (16.7 mM)-induced insulin secretion. The inhibitory effect was less when des-(phe-val-asp)B1-3-p-glu B4-insulin was employed and no inhibition of insulin secretion was observed by the use of pork C-peptide or proinsulin. Glucagon and somatostatin did not affect insulin binding. pH optimum of insulin binding appears to be in the range between 7.0 and 8.0. Binding was augmented with increasing temperature up to 37 degrees C. It is concluded that rat pancreatic islets possess insulin because binding and biological potency of substances related to insulin were in harmony. Moreover pH- and temperature-optimum of insulin binding are in a physiological range.
已证明分离的大鼠胰岛的结合位点可与胰岛素相互作用。利用各种种属的胰岛素、胰岛素类似物以及与胰岛素结构无关的物质，研究了胰岛素与大鼠胰岛结合的结构特异性以及pH和温度依赖性。大鼠胰岛素与猪胰岛素一样，以相同的浓度依赖性方式从其结合位点置换出125I胰岛素，而胰岛素类似物去（苯丙氨酸-缬氨酸-天冬氨酸）B1-3-γ-谷氨酸B4-胰岛素的效果较差。猪C肽几乎不竞争结合，猪胰岛素原根本不竞争。两种种属的胰岛素均抑制葡萄糖（16.7 mM）诱导的胰岛素分泌。使用去（苯丙氨酸-缬氨酸-天冬氨酸）B1-3-γ-谷氨酸B4-胰岛素时，抑制作用较小，而使用猪C肽或胰岛素原时未观察到胰岛素分泌的抑制作用。胰高血糖素和生长抑素不影响胰岛素结合。胰岛素结合的最适pH似乎在7.0至8.0之间。随着温度升高至37℃，结合增强。结论是大鼠胰岛具有胰岛素，因为与胰岛素相关的物质的结合和生物学活性是一致的。此外，胰岛素结合的pH和温度最适值在生理范围内。
