Oxalate influx rate in red blood cells in calcium oxalate nephrolithiasis

We established a method of human red blood cell oxalate influx rate under the condition of steady state exchange. Using this method we measured the influx rate in 10 patients with recurrent calcium oxalate nephrolithiasis and in 18 controls. DIDS inhibited oxalate flux across the human red blood cell membrane. This result suggested that band 3 protein mediates oxalate transport. Oxalate influx rate depended on reaction temperature and pH of reaction buffer. Although the oxalate influx rate in 4 degrees C could not be determined under an initial condition rate, the measurable condition was in 0 degrees C of reaction temperature. Consequently we measured the oxalate influx rate under the condition of 0 degrees C reaction temperature and 20 ml volume of washing buffer. The mean oxalate influx rate was significantly higher in patients with nephrolithiasis than in controls (-1.00 +/- 0.19 vs. -0.78 +/- 0.14).