The comparison of methylene blue and vitamin E in prevention of abdominal postoperative adhesion formation in rat uterine horn models: Biochemical and histopathologic evaluation / Comparação do azul de metileno e vitamina E na prevenção de aderência abdominal pós-operatória em corno uterino de ratos: avalição bioquímica e histopatológica

Purpose: To compare the effects of vitamin E and 1 percent methylen blue solutions on prevention of experimentally induced adhesions in rats. Methods: Thirty seven female Spraque Dawley rats were randomized into four groups. First group was kept as sham operated group. An adhesion model was constituted on the left uterine horn of the other groups. The lesion areas of rats from the second, the third and the fourth groups were coated with 2 ml 0.9 percent saline solution (C group), 10 mg vitamin E (VE group) and 1 percent methylen blue solutions (MB group), respectively. Results: Histopathologically, adhesion scores, mononuclear cell infiltration, oedema and fibrosis were more prominent in the MB group compared with C and VE groups. There were no significant differences between the groups in tissue glutathione peroxidase (GPx), catalase (CAT) activities and glutation (GSH) level, these parameters were slightly increased in group with VE supplementation though. The administration of VE and MB significantly decreased NO (P<0.01) levels when compared to the C group. The level of malondialdehyde (MDA) in the VE group was significantly lower (P<0.05) than those of the Sh and C groups. Conclusion: Intraperitoneal methylen blue solutions treatments were more effective according to vitamin E in preventing the formation of intra-abdominal adhesion in a rat uterine horn model.

Objetivo: Comparar os efeitos da vitamina E e 1 por cento da solução de azul de metileno na prevenção de aderências induzidas em ratos. Métodos: Trinta e sete ratos fêmeas Spraque Dawley foram distribuídos em quatro grupos. O primeiro grupo foi mantido como grupo sham. O modelo de aderência foi realizado no corno uterino esquerdo nos outros grupos. As áreas da lesão dos ratos do segundo, terceiro e quarto grupos foram revestidas com 2 ml de solução salina 0,9 por cento (Grupo C), 10 mg de vitamina E (Grupo VE) e solução de azul de metileno 1 por cento (Grupo MB), respectivamente. Resultados: Histopatologicamente, o escore das aderências, infiltração celular mononuclear, edema e fibrose foram mais proeminentes no grupo MB em comparação aos grupos C e VE. Não houve diferença significante entre os grupos na peroxidase da glutatione do tecido (GPx), atividade da catalase (CAT) e o nível de glutation (GSH). Estes parâmetros foram ligeiramente aumentados no grupo com suplemento da VE. A administração da VE e do MB diminuiu significantemente os níveis quando quando comparada ao Grupo C. O nível de malondialdeído no grupo VE foi significantemente mais baixo do que nos grupos sham e C. Conclusão: A administração intraperitoneal da solução de azul de metileno foi mais eficaz de acordo com a vitamina E na prevenção de aderências intra-abdominais no corno uterino de ratos.

Efficacy of vitamin E and selenium for the prevention of intra-abdominal adhesions in rats: uterine horn models

OBJECTIVE: This study compares the efficacies of vitamin E and selenium, both individually and in combination, for the prevention of postoperative intra-abdominal adhesions in rats. METHODS: Forty-seven female rats were divided into five groups. The sham animals (S group, n = 7) were given only laparotomies and intraperitoneally received 0.9 percent NaCl (2 ml). In the 40 other rats, abrasions of the left uterine horn were performed, followed by intraperitoneal administration of either 2 ml 0.9 percent NaCl (C group), 10 mg vitamin E (vitamin E group), 0.2 mg/kg selenium (Se group) or 10 mg vitamin E with 0.2 mg/kg selenium (vitamin E + Se group), with 10 animals in each treatment group. RESULTS: Adhesion formation was significantly reduced in animals in the Se and vitamin E + Se groups (p<0.05). Tissue catalase and glutathione peroxidase activities did not significantly differ between the groups. However, catalase and glutathione peroxidase activities and reduced glutathione levels were slightly increased in the vitamin E, Se and vitamin E + Se groups. In the vitamin E group, malondialdehyde concentrations were significantly lower than in the C group (p<0.05), but no significant differences were present among the S, C, Se and vitamin E + Se groups. Levels of nitric oxide were significantly higher in the C group than in the other groups (p<0.01). CONCLUSION: Intraperitoneal administration of selenium or combined vitamin E and selenium appears to be effective in preventing intra-abdominal adhesion formation in rat models through the reduction of lipid peroxidation products.