RESUMO
AIM: To investigate the levels of nitric oxide (NO) and asymmetric dimethylarginine (ADMA) in all the rat endometriosis models. MATERIAL & METHODS: Forty-one rats with endometriotic implants were divided into four groups (1 to 4) and administered infliximab, etanercept, letrozole and control, respectively. There were 11 rats in group 5 (normal). The size of implants, plasma ADMA and nitrate/nitrite (NO(x) ) levels and histological score were assessed. RESULTS: In groups 1, 2 and 3, plasma ADMA levels were higher than groups 4 and 5, 296.8 ± 66.2, 285.9 ± 35.7, 200.3 ± 41.0, 125.3 ± 16.7, 111.3 ± 6.5 µmol/L, respectively, while NO(x) levels were lower than groups of control and normal 19.6 ± 3.8, 19.8 ± 4.4, 39.3 ± 6.1, 80.5 ± 5.3, and 91.1 ± 5.0 µmol/L, respectively. CONCLUSIONS: Infliximab, etanercept and letrozole have regressed endometriotic implants, decreased plasma NO(x) levels, and increased plasma ADMA levels.