RESUMO
OBJECTIVES: To determine the efficacy of montelukast in comparison with cabergoline in the prevention of ovarian hyperstimulation syndrome (OHSS) in rats. MATERIAL AND METHODS: An experimental OHSS model was formed in 35 female Wistar rats. Rats (22 days old) were randomized into 5 groups, each containing 7 animals. The control group received no therapy; the mild OHSS group was administered pregnant mare serum gonadotropin (PMSG) 10 IU for 4 days, hCG 10 IU on the 5th day; the severe OHSS group received PMSG 10 IU for 4 days, hCG 30 IU on the 5th day The montelukast group: received montelukast 10 mg/kg/day and the cabergoline group was administered cabergollne 100 microg/kg/day via oral gavage for 6 days (days 22-27), in addition to those of severe OHSS. All groups were sacrificed on 28th day Body weight, ovarian diameter and weight, vascular permeability vascular endothelial growth factor (VEGF), semiquantitative VEGF receptor-1, and VEGF receptor-2 (VEGFR-2) immunohistochemistry were evaluated. RESULTS: Ovarian diameter and VEGF expression were significantly lower in the montelukast and cabergoline groups than in the severe OHSS group. While montelukast was more effective in limiting vascular permeability in the severe OHSS, cabergoline was superior to montelukast with respect to the limiting effect on increased body weight and VEGFR-2 expression. CONCLUSIONS: The VEGF/VEGFR-2 interaction plays an important role in OHSS pathogenesis. Montelukast limits VEGF expression, and cabergoline reduces both VEGF and VEGFR-2 expressions; they are both effective therapies for the prevention of severe OHSS.