effects of melatonin on histopathological changes after experimental ovarian torsion-detorsion in cat

background: during the detorsion of a torsioned ovary, oxidant agents are released and melatonin as an antioxidant can reduce ischemia. we studied the histopathological changes after using melatonin on experimental torsioned ovary in cat. objective: the aim of this experimental study was to investigate the effects of melatonin on histopathological changes in torsion – detorsion injury in cat ovary. materials and methods: an adnexal torsion – detorsion model was created by using 20 adult cats randomly divided equally in to 2 groups of saline and melatonin. ischemia was induced by iathrogenic 360° clockwise torsion of the cat adnex for 3 hr. reperfusion was achieved for 3 hr. melatonin or saline were injected intra peritoneally (10mg/kg) 30 min before ovarian detorsion in both groups. after 3 hr of ovarian detorsion, ovarian tissue was removed and fixed in 10% formalin solution, embedded in paraffin and evaluated for ischemic indices. results: histological examination showed a significant improvement in ovarian morphology in the melatonin treated cats. edema and vasoconstriction in saline group were more severe than melatonin group (p-value = 0.009). hemorrhage and leukocyte infiltration were also more obvious in saline group (p-value 0.0018) conclusion: our results demonstrated that melatonin administration reduced ovarian histopathological damage due to oxidative injury associated with torsion.