Objective: To study the effects of acute hypoxia and intermittent hypoxic acclimatization on cardiac systolic and diastolic functions in rats.
Method: Cardiac functions were investigated after intermittent hypoxic acclimatizated (3000 m and 5000 m, 2 wk respectively, 4 h/d) and normoxic rats were exposed to hypoxia (8000 m) for 4 h.
Result: The systolic functional parameters such as LVSP, +dp/dtmax, Vpm, Vmax and the diastolic functional parameter -dp/dtmax of acute hypoxic rats were reduced significantly as compared with normoxic control rats. After hypoxic acclimatization, the left ventricular functions of rats were increased significantly as compared with those of acute hypoxic rats. But they were still lower than those of normoxic control rats.
Conclusion: Acute hypoxia can affect cardiac functions and hypoxic acclimatization can alleviate the hypoxic effects on cardiac functions.