Abstract:

BACKGROUND: Hypoxia inducible factor 1 is a kind of transcription factor which plays a crucial role in the organism’s adaptation to changing oxygen tensions. It is closely related to the organism resistance to anoxia.
OBJECTIVE: To detect the expression of hypoxia inducible factor 1 and vascular endothelial CD34 protein expression in skeletal muscle tissues of rats receiving hypoxic training; to explore the effects of hypoxia inducible factor 1 on angiogenesis in skeletal muscle tissues.
METHODS: A total of 60 healthy male SD rats were randomly divided into six groups: normoxic control group, hypoxic sedentary group, normoxic training group, hypoxic residence plus hyperoxic training group, hyperoxic residence plus hypoxic training group and hyperoxic residence plus hyperoxic/hypoxic training group. Rats in training group were trained with increasing load treadmill exercise 6 days a week for 10 weeks. The exercise volume changed from 15 m/min for 25 minutes in the 1st week to 28 m/min for 50 minutes in the 10th week. Rats in hypoxic groups were trained every Tuesday, Thursday and Saturday under the hypoxia environment equivalent to 1 500 meters above sea level; and lived in low oxygen environments, whose hypoxic degree increased from that equivalent to 1 800 meters in the 1st week to that equivalent to 3 600 meters above sea level in the 10th week.
RESULTS AND CONCLUSION: Under the low oxygen condition, hypoxia inducible factor 1 had massive protein expression. The expression was more under the low oxygen environment combined with training. While CD34 protein expression was only detected in normoxic training group and hypoxic trainging group. It indicates that hypoxia inducible factor 1 is an important factor in the promotion of angiogenesis in skeletal muscle tissues, but it can produce positive effects only when combined with exercise.