Comparable effects of continuous exercise training and intermittent hypoxia on angiogenic upregulations in the heart tissue of male Wistar rats.

Objective: Angiogenesis can be influenced by many factors. The main purpose of the present study was to explore the effect of aerobic training and intermittent hypoxia on angiogenic factors in the cardiac tissue of male Wistar rats. Methods: Thirty male Wistar rats were randomly divided into one of three groups; normal control (NC), hypoxia (H), and training (T). The Hypoxia group was exposed to chronic periodic and isobaric hypoxia (total pressure PiO2~760 mmHg, 14% oxygen) for 8 weeks. Animals in the training group ran on a motorized treadmill (22-26 meters per min) for 8 weeks, 5 sessions per week. At the end of the procedure, protein expression of Tie-1, HIF-1a, VEGF, and P-AKT were calculated by an immunoblotting technique in the cardiac tissue. Results: The findings indicated that periodic hypoxia and exercise training substantially raised the expression of the HIF-1a, VEGF, and P-AKT proteins as compared to the NC (p = 0.001). Moreover, chronic treadmill training significantly increased the phosphorylation of AKT as compared to the hypoxia group (p = 0.001), indicating that PI3K/Akt signalling pathway is influenced by exercise training rather than hypoxia. Conclusion: It seems that both hypoxia and exercise training are potent stimulators for the induction of angiogenesis signalling pathway. [ABSTRACT FROM AUTHOR]