|Gasser S et al.|
Human Myocardial mRNA-Expression of Insulin-Dependent Transmembrane Glucose Transporter is Increased in Human IDDM and Decreased in NIDDM
Journal of Clinical and Basic Cardiology 2004; 7 (1-4): 8-10
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Keywords: Glukosetransport, Hypertonie, Kardiologie, cardiology, gene expression, glucose transport, hypertension
Transmembrane glucose transport and thus cellular high energy metabolism of the cardiovascular system depend largely on the insulin responsive GLUT4-isoform of the transmembrane glucose transport molecule. Several authors have shown that, in animals, myocardial GLUT4-mRNA expression is decreased in experimental diabetes. There are no data on humans as yet. Here, we investigate probes of right atrial auricle from diabetic and non diabetic patients subjected to cardiac surgery which were snap frozen in liquid nitrogen. Semiquantitative PCR has been used in order to quantify GLUT4-mRNA using G3PDH as a house keeping gene. Our results represent the first measurements of GLUT4-mRNA in human myocardial tissue. Seven patients had NIDDM (determined by OGT, HbA1C and insulin secretion), 7 had IDDM and 7 served as controls. Relative GLUT4-expression amounted to 97.0 ± 10.4 ( ± SEM) in the control group, 133.3 ± 15.2 in the IDDM-group and 49.1 ± 6.2 ( ± SEM) in the NIDDM-group. From these data we deduce that DM is initially associated with a decreased GLUT4-expression, the latter then being upregulated by external application of insulin.