RESUMEN
Objective To observe the effects of low-frequency pulsed electromagnetic fields (LFPEMFs) on microcirculation angiogenesis in the hindlimbs of diabetic rats with acute ischemia. Methods Models of acute hindlimb ischemia were established in 60 male Sprague-Dawley diabetic rats. The diabetes model was established using 60 mg/kg intraperitoneal injections of streptozotocin (STZ). Fasting blood glucose levels were greater than 300 mg/dL. The rats were randomly divided into experimental and control groups. The rats in the experimental group were exposed to low-frequency pulsed electromagnetic fields for 2 hours each day, while the control group was not given any treatment. Laser-Doppler perfusion was used to measure blood flow in the ischemic hindlimb on days 0,7, 14 and 28 after the operation. The immunofluorescence of rat endothelial cell antigen-1 ( RECA-1) was used to evaluate the changes in angiogenesis. The levels of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) were determined by both Western blotting and ELISA, and VEGFR2 and FGFR1 levels in the ischemic skeletal muscle were determined by Western blotting on days 7, 14 and 28 after the operation. Results The average perfusion ratio was significantly greater in the experimental group at days 14 and 28 compared with the control group. RECA-1 density in the tissues had increased significantly in the experimental group at the 14th and 28th day. The same was observed for FGF-2 and its receptor, but there was no significant difference for VEGF or its receptor in either group. Conclusions LFPMEFs can promote angiogenesis in acute hindlimb ischemia of diabetic rats by up-regulating FGF-2. This suggests that LFPMEFs may be useful for preventing and treating lower limb ischemia in diabetic humans.