| 1 | Roles of sulfonylurea receptor 1 and multidrug resistance protein 1 in modulating insulin secretion in human insulinoma显示文摘BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion. METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls. Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry. SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence. RESULTS:Insulinoma patients presented the typical demons-trations of Whipple's triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients. Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets. CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1. In contrast,MRP1,which is down-regulated in insulinomas, might reflect a negative feedback in insulin secretion. | Cheng-Jiang Li,Hua-Li Zhou,Jun Li,Hong-Tian Yao,Rong Su and Wen-Peng Li Department of Endocrinology(Li CJ,Zhou HL and Li WP),Department of Pathology,and Key Laboratory of Multi-organ Transplantation of Ministry of Public Health,First Affiliated Hospital,Zhejiang University School of Medicine,Hangzhou 310003,China | 2011 | Hepatobiliary & Pancreatic Diseases International2011，10，1： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员