Differences in myocardial and peripheral VEGF and KDR levels after acute ischemia

Background. Recent clinical use of vascular endothelial growth factor (VEGF ) in the treatment of both myocardial and peripheral ischemia has suggested the possibility of tissue specific coregulation of VEGF and its receptors (eg, kinase domain region [KDR]). The present study was performed to detect the relationship between VEGF and KDR protein levels after acute myocardia l and peripheral ischemia. Methods. Eleven dogs were divided into two groups: peripheral ischemia (n = 6,ligation of major limb arteries) and myocardial ischemia (n = 5, circsum flex artery ligation). Muscle biopsy specimens were taken from the perfusio n territories of the occluded circumflex artery and limb arteries 3 hours a nd 6 hours after ligation. Protein levels were determined using Western blo t analysis. Results. In myocardium, VEGF levels increased on average eightfold from bas eline (p < 0.05) both 3 hours and 6 hours after occlusion, whereas myocardi al KDR levels dropped by about 60% at 3 hours and 80% at 6 hours (p < 0.05) . With limb ischemia, both VEGF and KDR levels were significantly elevated at 3 hours. Conclusions. In acute ischemia, regulation of VEGF and KDR may be controlle d differently in cardiac and skeletal muscle. Myocardial KDR levels showed a significant decrease from baseline compared with a significant rise with peripheral ischemia. (C) 2000 by The Society of Thoracic Surgeons.