الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was planned to investigate the impact of CIH on female fertility and evaluate the adaptogenic activity of L-arginine supplementation and its anti-stress effect on female fertility. The study was performed on 48 adult female albino rats, divided into the following groups: group I: Control group (n=16), rats were housed (4 rats/cage) in room air. Also rats received distilled water (the solvent of L-arginine), 5 days/week for 12 weeks by oral gavage. group II: Hypoxic group (n=16), rats were subjected to hypoxia for 8 hours/day, 5 days/week for 12 weeks. Also rats received distilled water (the solvent of Larginine) 30 min prior to exposure to hypoxia, 5 days/week for 12 weeks by oral gavage. group III: Hypoxic-supplemented group (n=16), rats were supplemented with L-arginine by oral gavage in a dose of 100 mg/kg body weight 30 min prior to exposure to hypoxia, 5 days/week for 12 weeks. All the studied groups were subjected to: Body weight measurement every two weeks for 12 weeks. Determination of phases of estrous cycle by vaginal smear. Ovarian weight measurement and determination of gonado-somatic index. Measurement of haematocrit value. Determination of plasma levels of progesterone and LH hormones. Evaluation of oxidative stress by measuring MDA level in the ovarian tissue. Evaluation of anti-oxidative capacity by measuring CAT enzyme activity in the ovarian tissue. Evaluation of apoptosis at germinal cell level by measuring the caspase-3 enzyme level in the ovarian tissue. Examination of histopathological changes in the ovarian tissue. The study revealed that the exposure to CIH significantly resulted in increased HV, decreased body weight and increased ovarian tissue MDA level that was associated with decreased CAT enzyme activity. Asignificant increase in LH plasma levels was observed in both rats with regular cycle and those with irregular cycle. Also there was a higher rate of mortality and increased incidence of rats with irregular cycle among hypoxic group compared to the control group. Histopathological examination of ovarian sections from rats exposed to CIH showed alterations and changes indicating hypoxic stress compared to their matching controls. At the same time, the immunohistochemical study showed an increase in the expression of caspase-3 enzyme in ovarian tissue of the hypoxic group. On the other hand pretreatment with L-arginine showed an improvement in most of the parameters investigated in this study compared to the hypoxic group as shown by the significant increase in body weight, decrease in MDA level, decrease in LH hormone levels in addition to lower incidence of cycle irregularity and rate of mortality. There was also improvement in histopathological picture as well as lowered caspase-3 enzyme expression in the ovarian tissue. This improvement could be explained by the role of L-arginine, the endogenous precursor of NO, as antioxidant and anti-apoptotic in addition to its anti-inflammatory properties. |