Improving Angiogenesis and Muscle Performance in the Ischemic Limb Model by Physiological Ischemic Training in Rabbits

Zhao Y, Li J, Lin A, Xiao M, Xiao B, Wan C: Improving angiogenesis and muscle performance in the ischemic limb model by physiological ischemic training in rabbits. Am J Phys Med Rehabil 2011;90:1020-1029. Objective: The aim of this study was to test the effects of physiologic ischemic training on the performance of skeletal muscle in a pathologically ischemic limb models. Design: Twenty-seven New Zealand white rabbits were randomly assigned to three groups: (1) those in the ischemia with cuff inflation training group received right femoral artery ligation and occlusion of blood flow in the left limb by 3 mins of cuff inflation followed by 5 mins of deflation, repeated three times; (2) those in the ischemia with isometric exercise training group received right femoral artery ligation and 4 mins of isometric contraction exercise ischemic training in the left limb followed by 10 mins of rest, repeated twice; (3) those in the sole ischemia group received right femoral artery ligation and no intervention in the left limb. Five weeks later, muscle endurance, resting blood flow, and collateral angiogenesis were examined. Capillary supply, types and cross-sectional areas of muscle fibers and cellular oxidative potential were also evaluated. Results: Gastronomic endurance of rabbits in the cuff inflation training group was the best among the three groups (P < 0.01). Collateral circulation (P < 0.05), distribution of type I fibers (P < 0.01), and cross-sectional area of type IIB fibers (P < 0.05) were also significantly higher in the cuff inflation training group than in the sole ischemia group. Similar differences were recorded between the isometric exercise training and sole ischemia groups. The distribution of type IIA fibers was lower (P < 0.01) in the cuff inflation training group than in the isometric exercise training group. Distribution of type IIB was found to be significantly different between these two groups (P < 0.01). Conclusions: Physiologic ischemic exercise training can promote remote angiogenesis in the pathologic ischemic skeletal muscle and thus improve performance.