Effect of ischemia or hypoxia on vascular endothelial growth factor production in rat myocardium and its significance

AIM:To determine the relationship between ischemia, hypoxia and the production of vascular endothelial growth factor in rat myocardium and its basic mechanism. METHODS:(1) 28 Wistar rats were randomly divided into 4 groups: group A, normal control;group B, 1 day's acute myocardial infarction;group C, 3 day's acute myocardial infarction;group D, 7 day's acute myocardial infarction. (2) Rat cardiac myocytes cultured were primarily divided into some groups, hypoxia incubated 24 hours; PMA groups, hypoxia incubated 24 hours with PKC activator (PMA), A 0 ng/mL; B 10 ng/mL; C 100 ng/mL; D 1 000 ng/mL; Chelerythrine groups, hypoxia incubated 24 hours with PKC inhibitor (chelerythrine), A 0 nmol/L; B 10 nmol/L. (3) By computer scanned and quantitated, vascular endothelial growth factor (VEGF) protein was detected with immunohistochemical technique. RESULTS:The longer time of ischemia and hypoxia was, the higher the VEGF production.The relat ionship was found between the time of ischemia or hypoxia and the production of VEGF.The product ion of VEGF protein was further promoted by PMA with different concentrat ion, decreased by chelerythrine.CONCLUSION: Ischemia or hypoxia strongly stimulated the production of VEGF in myocardium, which played an important role in autoprotecting of ischemic or hypoxic myocardium. Hypoxia-induced PKC activation is one kind of basic mechanisms in this course.