Please use this identifier to cite or link to this item:
Title: Insulin-induced recruitment of glucose transporter 4 (GLUT4) and GLUT1 in isolated rat cardiac myocytes. Evidence of the existence of different intracellular GLUT4 vesicle populations
Author: Fischer, Yvan
Thomas, Julia
Sevilla, Lidia
Muñoz Moruno, Purificación
Becker, Christoph
Holman, Geoffrey
Kozka, Izabela J.
Palacín Prieto, Manuel
Testar, Xavier
Kammermeier, Helmut
Zorzano Olarte, Antonio
Keywords: Hipoglucèmia
Proteïnes portadores
Carrier proteins
Issue Date: 14-Mar-1997
Publisher: American Society for Biochemistry and Molecular Biology
Abstract: Using isolated rat cardiomyocytes we have examined: 1) the effect of insulin on the cellular distribution of glucose transporter 4 (GLUT4) and GLUT1, 2) the total amount of these transporters, and 3) the co-localization of GLUT4, GLUT1, and secretory carrier membrane proteins (SCAMPs) in intracellular membranes. Insulin induced 5.7- and 2.7-fold increases in GLUT4 and GLUT1 at the cell surface, respectively, as determined by the nonpermeant photoaffinity label [3H]2-N-[4(1-azi-2,2,2-trifluoroethyl)benzoyl]-1, 3-bis-(D-mannos-4-yloxy)propyl-2-amine. The total amount of GLUT1, as determined by quantitative Western blot analysis of cell homogenates, was found to represent a substantial fraction ( approximately 30%) of the total glucose transporter content. Intracellular GLUT4-containing vesicles were immunoisolated from low density microsomes by using monoclonal anti-GLUT4 (1F8) or anti-SCAMP antibodies (3F8) coupled to either agarose or acrylamide. With these different immunoisolation conditions two GLUT4 membrane pools were found in nonstimulated cells: one pool with a high proportion of GLUT4 and a low content in GLUT1 and SCAMP 39 (pool 1) and a second GLUT4 pool with a high content of GLUT1 and SCAMP 39 (pool 2). The existence of pool 1 was confirmed by immunotitration of intracellular GLUT4 membranes with 1F8-acrylamide. Acute insulin treatment caused the depletion of GLUT4 in both pools and of GLUT1 and SCAMP 39 in pool 2. In conclusion: 1) GLUT4 is the major glucose transporter to be recruited to the surface of cardiomyocytes in response to insulin; 2) these cells express a high level of GLUT1; and 3) intracellular GLUT4-containing vesicles consist of at least two populations, which is compatible with recently proposed models of GLUT4 trafficking in adipocytes.
Note: Reproducció del document publicat a:
It is part of: Journal of Biological Chemistry, 1997, vol. 272, num. 11, p. 7085-7092
Related resource:
ISSN: 0021-9258
Appears in Collections:Articles publicats en revistes (Ciències Fisiològiques)
Articles publicats en revistes (Bioquímica i Biomedicina Molecular)

Files in This Item:
File Description SizeFormat 
114264.pdf472.45 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.