title: GLUT4 in the endocrine pancreas--indicating an impact in pancreatic islet cell physiology?
abstract: The glucose transporter GLUT4 is well known to facilitate the transport of blood glucose into insulin-sensitive muscle and adipose tissue. In this study, molecular, immunohistochemical, and Western blot investigations revealed evidence that GLUT4 is also located in the mouse, rat, and human endocrine pancreas. In addition, high glucose decreased and insulin elevated the GLUT4 expression in pancreatic α-cells. In contrast, high glucose increased GLUT4 expression, whereas insulin led to a reduced expression level of the glucose transporter in pancreatic β-cells. In vivo experiments showed that in pancreatic tissue of type 2 diabetic rats as well as type 2 diabetic patients, the GLUT4 expression is significantly increased compared to the nondiabetic control group. Furthermore, type 1 diabetic rats exhibited reduced GLUT4 transcript levels in pancreatic tissue, whereas insulin treatment of type 1 diabetic animals enhanced the GLUT4 expression back to control levels. These data provide evidence for the existence of GLUT4 in the endocrine pancreas and indicate a physiological relevance of this glucose transporter as well as characteristic changes in diabetic disease.
authors.affiliation: Institute of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Bähr
authors.forename: I
authors.initials: I
authors.lastname: Bazwinsky-Wutschke
authors.forename: S
authors.initials: S
authors.lastname: Wolgast
authors.forename: K
authors.initials: K
authors.lastname: Hofmann
authors.forename: S
authors.initials: S
authors.lastname: Streck
authors.forename: E
authors.initials: E
authors.lastname: Mühlbauer
authors.forename: D
authors.initials: D
authors.lastname: Wedekind
authors.forename: E
authors.initials: E
authors.lastname: Peschke
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D000918:Antibody Specificity / Q000276:immunology; D002460:Cell Line; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics / Q000503:physiopathology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D051273:Glucose Transporter Type 2 / Q000235:genetics / Q000378:metabolism; D051275:Glucose Transporter Type 4 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007515:Islets of Langerhans / Q000187:drug effects / Q000473:pathology* / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D051273:Glucose Transporter Type 2; D051275:Glucose Transporter Type 4; D007328:Insulin; D012333:RNA, Messenger; D005947:Glucose