This study assessed the effects of a simulated high-altitude environment on the reproductive system of prepubertal male rats and the reversibility of these effects upon return to a normal environment. Three-week-old male Wistar rats were randomly allocated to 4 groups that were exposed to different conditions: a normal environment for 6 weeks and 12 weeks, respectively, hypobaric hypoxia for 6 weeks, and hypobaric hypoxia for 6 weeks followed by a normal environment for 6 weeks. Multiple pathophysiological parameters were evaluated at the histological, endocrine, and molecular levels. Hypobaric hypoxia exposure for 6 weeks during the prepubertal phase significantly altered physiological parameters, body functions, blood indices, and reproductive potential. Six weeks after returning to a normal environment, the damaged reproductive functions partially recovered due to compensatory mechanisms. However, several changes were not reversed after returning to a normal environment for 6 weeks, including disorders of body development and metabolism, increased red blood cells, increased fasting blood glucose, abnormal blood lipid metabolism, decreased testicular and epididymis weights, abnormal reproductive hormone levels, excessive apoptosis of reproductive cells, and decreased sperm concentration. In summary, a hypobaric hypoxic environment significantly impaired the reproductive function of prepubertal male rats, and a return to normal conditions during the postpubertal phase did not fully recover these impairments.
Keywords: high altitude; hypobaric hypoxia; male rats; reproductive potential; testis.