【摘要】 目的：研究甜菜碱对大鼠肝细胞膜表皮生长因子（ｅｐｉｄｅｒｍａｌｇｒｏｗｔｈｆａｃｔｏｒ，ＥＧＦ）受体及其酪氨酸蛋白激酶（ｔｙｒｏｓｉｎｅｐｒｏｔｅｉｎｋｉｎａｓｅ，ＴＰＫ）活性的影响。方法：应用受体的放射配基结合分析法（ｒａｄｉｏｌｉｇａｎｄｂｉｎｄｉｎｇａｓａｙｏｆｒｅｃｅｐｔｏｒｓ，ＲＢＡ），比较实验组和对照组之间１２５ＩＥＧＦ与其受体的结合情况；受体酪氨酸蛋白激酶活性测定法，以大鼠肝细胞膜可溶性蛋白为酪氨酸蛋白激酶来源，比较实验组和阴性组之间受体蛋白自身磷酸化作用的差异。结果：２６ｎｍｏｌ·Ｌ－１～５．２ｍｍｏｌ·Ｌ－１的甜菜碱均能抑制正常大鼠肝细胞膜ＥＧＦ受体与其配基的结合，这种抑制作用为非竞争性抑制；１０与１００μｍｏｌ·Ｌ－１的甜菜碱可激活酪氨酸蛋白激酶活性，而１０ｍｍｏｌ·Ｌ－１的甜菜碱则抑制酪氨酸蛋白激酶活性。结论：甜菜碱可以抑制ＥＧＦ受体与其配基的结合并影响ＥＧＦ受体的酪氨酸蛋白激酶活性。更多还原

【Abstract】 Objective: To study the effect of betaine on EGF receptor and its tyrosine protein kinase activity of rat liver cell membrane. Methods: Radioligand binding assay of receptor, comparing the binding of 125 I EGF to its receptor between test groups and the control group; Receptor tyrosine protein kinase activity test, using the soluble proteins of rat liver cell membrane as the source of tyrosine protein kinase to compare the autophosphorylation difference between test groups and the negative group. Results: 26 nmol· L -1 ～5.2 mmol·L -1 betaine inhibited the binding of EGF receptor with EGF in a noncompetitive way, 10, 100 μmol·L -1 betaine stimulated TPK activity, but inhibited TPK activity when concentration was up to 10 mmol·L -1 . Conclusion: Betaine can inhibit the binding of EGF receptor with EGF and affect TPK activity conspicuously.更多还原