Evolution of total antioxidant status in a model of acute renal insufficiency in rats

Accurate estimation of the Total Antioxidant Status (TAS) in the myoglobinuric acute renal failure (ARF) is necessary because its pathogenesis is believed to be mediated, at least in part, by the development of oxidative stress resulting from the generation of oxygen free radicals and reduced antioxidant defense system. The purpose of this study is to examine the TAS 24 and 72 h after glycerol injection in a model of myoglobinuric-ARF.

The study was conduced in 28 Sprague-Dawley rats. In group 1 (n = 7) rats were placed into individual metabolic cages and deprived of water during 24 h. afterwards an intramuscular injection of glycerol was administrated (50% vol/vol in sterile saline) 10 mg/100 g of body weight and 24 h later blood samples were collected for biochemical measurements (urea, creatinine, creatine-kinase, and TAS levels). In group 2 (n = 7), rats followed the same conditions than group 1 ones but blood samples were collected 72 h after glycerol injection. In groups 3 (n = 7) and 4 (n = 7) rats didn't receive glycerol injection, and blood samples were collected within 24 and 72 h respectively after they were placed into metabolic cages.

In groups 1 and 2 we observed a renal function decrease, with higher serum levels of urea and creatinine in group 2 (urea levels: 269 +/- 16 mg/dL vs. 586 +/- 147 mg/dL; p < 0.001. Creatinine levels: 2.8 +/- 0.2 mg/dL vs. 5.8 +/- 0.7 mg/dL; p < 0.001). TAS levels in groups 2, 3, and 4 were similar, but in group 1 was significantly lower (group 1: 0.81 +/- 0.2 mmol/L; group 2: 1.3 +/- 0.1 mmol/L; group 3: 1.2 +/- 0.3 mmol/L, and group 4: 1.2 +/- 0.2 mmol/L; p < 0.005).

In the model of glycerol induced myoglobinuric-ARF we observed a decrease of serum TAS level within 24 h with spontaneous recuperation 72 h after.