CALL FOR PAPERS Renal Hemodynamics Glomerular filtration rate determinations in conscious type II diabetic mice

Bivona BJ, Park S, Harrison-Bernard LM. Glomerular filtration rate determinations in conscious type II diabetic mice. Am J Physiol Renal Physiol 300: F618–F625, 2011. First published December 8, 2010; doi:10.1152/ajprenal.00421.2010.—Diabetic nephropathy is a major cause of end-stage renal disease worldwide. The current studies were performed to determine the later stages of the progression of renal disease in type II diabetic mice (BKS; db/db). Methodology was developed for determining glomerular filtration rate (GFR) in conscious, chronically instrumented mice using continuous intravenous infusion of FITC-labeled inulin to achieve a steady-state plasma inulin concentration. Obese diabetic mice exhibited increased GFR compared with control mice. GFR averaged 0.313 0.018 and 0.278 0.007 ml/min in 18-wk-old obese diabetic (n 11) and control (n 13) mice, respectively (P 0.05). In 28-wk-old obese diabetic (n 10) and control (n 15) mice, GFR averaged 0.348 0.030 and 0.279 0.009 ml/min, respectively (P 0.05). GFR expressed per gram BW was significantly reduced in 18and 28-wk-old obese diabetic compared with control mice (5.9 0.3 vs. 9.0 0.3; 6.6 0.6 vs. 7.8 0.3 l·min ·g body wt ), respectively (P 0.05). However, older nonobese type II diabetic mice had significantly reduced GFR (0.179 0.023 ml/min; n 6) and elevated urinary albumin excretion (811 127 g/day) compared with obese diabetic and control mice (514 54, 171 18 g/day), which are consistent with the advanced stages of renal disease. These studies suggest that hyperfiltration contributes to the progression of renal disease in type II diabetic mice.