Arginine, symmetric and asymmetric dimethylarginine levels in the molsidomine treatment of experimental ischemia-reperfusion retinopathy

This study aimed to evaluate the mean changes in Arginine, Asymmetric Dimethylarginine (ADMA) and Symmetric Dimethylarginine (SDMA) levels in the ischemia/ reperfusion (I/R) retinopathy and efficacy of treatment with molsidomine by these levels. Experiments were performed on the New Zealand white rabbits each weighing approximately 2.5 kg. 28 rabbits were assigned to the following 4 groups, group 1 consisted sham, group 2 consisted I/R, group 3 consisted I/R+ treatment with molsidomine, group 4 consisted prophylaxis with molsidomine +I/R. In the group 2, 3 and 4, ischemia was induced by raising the intraocular pressure to 150 mmHg for 60 minutes. After 60 min, the IOP was returned to normal pressure. 4 mg/kg/day molsidomine was administered intraperitoneally four days after I/R in group 3, one day before I/R and three days after I/R in group 4. Arginine, ADMA and SDMA levels were measured on the aqueous humor. The mean arginine levels were 12.3±4.8 μmol/L in group 1, 12.4±1.4 μmol/L in group 2, 13.2±2.4 μmol/L in group 3 and 13.7±4.3 μmol/L in group 4. No difference was present between the groups (p=0.807). The mean ADMA levels were 2.6±0.8 μmol/L, 7.3±2.7 μmol/L, 0.5±0.5 μmol/L and 2.5±1.0 μmol/L respectively. Significant increase was present in the group 2 and significant decrease was present in the group 3 (p=0.001). The mean SDMA levels were 1.0±0.3 μmol/L, 1.8±0.2 μmol/L, 0.3±0.3 μmol/L and 1.0±0.4 μmol/L respectively. Significant increase was present in the group 2 and significant decrease was present in the group 3 (p=0.001). L-Arginine levels were kept steady, ADMA and SDMA values decreased with molsidomine. Four days treatment with molsidomine after I/R may be beneficial more than prophylaxis and three days treatment.