OBJECTIVE: Sterilization (tubal sterilization and vasectomy) is a widely applied contraceptive method worldwide. Although most studies have described sterilization as a safe method, there are reports of tubal ligation (TL) and vasectomy complications. The aim of this study was to evaluate the effects of TL and vasectomy on the serum oxidative stress, specifically prooxidant-antioxidant balance (PAB) and malondialdehyde (MDA) levels, over time. METHODS: Male and female rats were classified into vasectomy, sham-vasectomy, TL, and sham-TL groups, respectively. The PAB and MDA levels were measured on days 15 and 45 and months 3 and 6 after the intervention. For female rats, blood sampling was performed during the diestrous phase and estradiol and progesterone were also measured. RESULTS: Serum PAB and MDA increased after TL (p<0.05). Vasectomy increased serum MDA remarkably after 45 days, 3 months, and 6 months (p<0.05). After vasectomy, serum PAB also increased although not significantly. Serum estradiol and progesterone decreased remarkably in the TL group compared to the sham group (p<0.05). CONCLUSION: Bilateral TL and vasectomy both increase the serum oxidative stress; however the imbalance after TL was very noticeable. As for the TL, the reduction of serum estrogen levels can be involved in this imbalance. Complications followed by TL or vasectomy could be due to increased levels of oxidants. Thus, prescribing antioxidants during and or after surgery may be a solution.
Adult ; Animals ; Antioxidants ; Contraception ; Estradiol ; Estrogens ; Female ; Humans ; Male ; Malondialdehyde ; Oxidants ; Oxidative Stress ; Progesterone ; Rats ; Salicylamides ; Sterilization ; Sterilization, Tubal ; Vasectomy

OBJECTIVE: Stress is known to be an inhibitor of the reproductive hypothalamic-pituitary-gonadal (HPG) axis. However, the neural and molecular connections between stress and reproduction are not yet understood. It is well established that in both humans and rodents, kisspeptin (encoded by the kiss1 gene) is a strong stimulator of the HPG axis. In the present study we hypothesized that endocannabinoids, an important neuromodulatory system in the brain, can act on the HPG axis at the level of kiss1 expression to inhibit reproductive function under stress. METHODS: Adult male Wistar rats were unilaterally implanted with an intracerebroventricular cannula. Afterwards, the animals were exposed to immobilization stress, with or without the presence of the cannabinoid CB1 receptor antagonist AM251 (1 microg/rat). Blood samples were collected through a retro-orbital plexus puncture before and after stress. Five hours after the stress, brain tissue was collected for reverse transcriptase-quantitative polymerase chain reaction measurements of kiss1 mRNA. RESULTS: Immobilization stress (1 hour) resulted in a decrease in the serum luteinizing hormone concentration. Additionally, kiss1 gene expression was decreased in key hypothalamic nuclei that regulate gonadotrophin secretion, the medial preoptic area (mPOA), and to some extent the arcuate nucleus (ARC). A single central administration of AM251 was effective in blocking these inhibitory responses. CONCLUSION: These findings suggest that endocannabinoids mediate, at least in part, immobilization stress-induced inhibition of the reproductive system. Our data suggest that the connection between immobilization stress and the HPG axis is kiss1 expression in the mPOA rather than the ARC.
Adult ; Animals ; Arcuate Nucleus ; Axis, Cervical Vertebra* ; Brain ; Cannabinoids ; Catheters ; Endocannabinoids* ; Gene Expression ; Humans ; Immobilization ; Kisspeptins ; Luteinizing Hormone ; Male* ; Polymerase Chain Reaction ; Preoptic Area ; Punctures ; Rats* ; Rats, Wistar ; Receptor, Cannabinoid, CB1 ; Reproduction ; RNA, Messenger ; Rodentia