Effect of sodium bicarbonate in an experimental model of radiocontrast nephropathy

Abstract

Aim: The aim of this study is to investigate the efficacy and mechanism of action of intravenous (IV) bicarbonate in preventing radiocontrast nephropathy (RCN). Materials and methods: Twenty-eight Wistar rats were randomized into four groups including control (group 1), radiocontrast (group 2), bicarbonate (group 3), and radiocontrast plus bicarbonate (group 4). Once blood chemistry and arterial blood gases were examined and 24 h urine samples were collected, all rats were administered furosemide (2 mg/kg subcutaneous) and deprived of water for 24 h. Iothalamate sodium (6 mL/kg) was administered to group 2 and group 4. IV bicarbonate (8.4%) was administered to group 3 and group 4 (3 h before the administration of iothalamate). On the fourth day, 24 h urine was collected, and at the end of the day rats were sacrificed and blood chemistry and arterial blood gases were reexamined. Myeloperoxidase (MPO), nitric oxide (NO), total glutathione, and malondialdehyde were quantified on the renal tissue. H&E slides were examined. Results: Basal creatinine and creatinine clearance were similar between groups. There was no significant difference between creatinine and creatinine clearance by the end of the experiment. Glutathione level in group 2 was lower than in group 4. Histopathologically, there was no injury in the control group (group 1) whereas there was an intermediate-severe injury (71.4%) in the radiocontrast group (group 2). The percentage of intermediate-severe injury was significantly lower (71.4% vs. 28.6%, p = 0.02) in the radiocontrast plus bicarbonate group (group 4). Conclusions: Sodium bicarbonate attenuates the development of radiocontrast-induced tubular necrosis.