A-15R Free Communication/Poster Peripheral Circulation
Prolonged exercise training exerts a profound angiogenic response in the active skeletal muscle. This increase in capillarity is thought to be mediated by angiogenic growth factors.
We evaluated whether this angiogenesis is dependent on vascular endothelial growth factor (VEGF) by using a specific, high-affinity VEGF receptor (VEGF-R) antagonist.
Male Sprague Dawley rats (∼325 g) with bilateral occlusion of the femoral arteries, were divided into Sedentary (Sed; limited to cage activity, n = 15), Trained (Tr; by running at 20 m/min, 15% grade, twice/d, for 18 d, n = 17), or Trained+VEGF-R antagonist (ZD 4190 ∼15 mg/kg/d for 14 d via gavage, n = 19) groups. White gastrocnemius muscles from each group were sectioned and stained for capillaries with alkaline phosphatase method.
Running duration increased to ∼2 hr/d after 5 th day of training. Exercise training increases capillary contacts per fiber (CC/F) from 2.73 ± 0.10 (Sed group) to 3.27 ± 0.11 (Tr group) (p < 0.001). VEGF-R antagonist reduced the CC/F to 3.02 ± 0.10 (Tr+VEGF-R antagonist group) (p < 0.05). CONCLU-SION: Our results indicate that VEGF-R antagonist reduced but did not eliminated the exercise-induced angiogenesis. This implies that VEGF is essential for part, but not necessarily all, of the angiogenic response induced in the skeletal muscle by exercise training. Supported by NIH grant HL38387, HL10406, and HL 10485.