STRESS DURING PUBERTY EXERTS LONGLASTING SEX-SPECIFIC REPRODUCTIVE EFFECTS IN ADULT RATS

Abstract

Adolescence is one of the critical periods of individual development, which is highly sensitive to changes caused by stress factors. Stress-related hormonal imbalances can negatively affect puberty and reproductive function. The aim of the study was to investigate the long-lasting reproductive effects of chronic pubertal stress in rats. Animals were subjected to immobilization stress daily from 30 to 45 postnatal day by placing them for 1 h in cylinders 4.5 cm in diameter and 10 cm in long, equipped with breathing holes. The timing of puberty in animals was studied and their somatic development was assessed. Further studies were conducted in 6-month-old sexually mature rats. The results were compared with the corresponding parameters in intact animals. Pubertal stress delayed sexual maturation in females and decreased weight gain in males. In adult animals of both sexes, pubertal stress did not change testosterone levels or the weight and morphology of the gonads significantly, except for minor vacuolation of the spermatogenic epithelium. The spermatogenesis index in the experimental group was significantly lower than in the control, due to a decrease in the number of late spermatids. Pubertal stress led to a 25.9% decrease in the number of spermatozoa in epididymal washes, an increase in the number of their pathological forms and a 2.4-fold slowdown in oxidative-reductive processes in spermatozoa. The content of malonic dialdehyde increased in the testes and ovaries, which indicates the activation of lipid peroxidation. Thus, chronic pubertal stress led to a decrease in the reproductive potential of male rats. Females are less susceptible to the negative effects of pubertal stress.