The effects of administration of melatonin in uterine torsion

Abstract

In this study, the effects of melatonin administration on spontaneous myometrial contractions in pregnant rats with induced uterine tor-sion were investigated. Uterine torsion was induced experimentally in thirty- five rats pregnant 18–19 days. The animals were randomly split into five groups (n = 7 rats per group). The rats in group 1 under-went anesthesia alone. In the rats in group 2, 360 degrees of uterine torsion was induced and corrected 6 h later. In the rats in group 3, 360 degrees of uterine torsion was induced and corrected 6 h later, and melatonin (10 mg/kg IP) was administered at the same time. In the rats in group 4, 360 degrees of torsion was induced, melatonin (10 mg/kg IP) was administered, and the torsion was corrected 6 h later. In group 5, on days 15–16 of pregnancy the rats were given melatonin (10 mg/kg/day IP), and on days 18–19 of the same preg-nancies, 360 degrees of uterine torsion was induced and corrected 6 h later. All animals underwent ovariohysterectomy the first day after giving birth and samples were taken from the uterine horns. The amplitude, frequency, and area under the contractile curve of sponta-neous uterine contractions were determined in all groups. As a result of the organ bath experiments, more myometrial contractions were found in the animals that were administered melatonin together with detorsion (group 3) than in the other groups (except for the control group). (This study was supported by the Scientific and Technological Research Council of Turkey, TUBITAK - 115O381)