|Gasser R et al.|
Insulin-Dependent Transmembrane Glucose Transport in Cardiovascular Disease
Journal of Clinical and Basic Cardiology 2006; 9 (1-4): 1-3
Keywords: Glukose, insuline, Myokard, glucose, GLUT4, Insulin, myocardial
In mammals, the transport of glucose across cell membranes occurs by facilitated diffusion. Several cDNAs encoding structurally related proteins with the properties of facilitative glucose transporters have been isolated and characterized (GLUT). These molecules regulate transmembrane glucose transport in various tissues. While different types of muscle fibres contain different levels of GLUT 4 proteins and gene expression as well as different insulin sensitivities, the nutritional state and contractile activity appear to regulate GLUT4 gene expression. While the complete cascade of interactions between glucose-metabolism and hypertension has not been elucidated completely as yet, transmembrane glucose transport is certainly crucial in this setting. Glucose and high-energy metabolism play a pivotal role in the development of numerous salient characteristics of myocardial ischemia, such as the gating properties of specific ion-channels, intracellular ion-homeostasis, electrical phenomena, contractility and other phenomena. Many of these aspects of myocardial ischemia are linked in one way or the other to transmembrane glucose transport, intracellular glucose metabolism and, in fact, to GLUT4.