Mesangial kinetics after partial nephrectomy in rats fed a normal or a low-protein diet

Mesangial kinetics of aggregated BSA (aggBSA) were studied inrats subjected to 1 1/3 nephrectomy (47sol;6 Nx) fed eithera normal (16%) or a low-protein (8%) diet. At 4 weeks postsurgery,ablated rats exhibited modest elevations in blood pressure buthad neither significant proteinuria nor evidence of glomerulardamage. Following injection of aggBSA into 4/6 Nx rats (16%diet) there was a marked increase in mesangial localizationat 4 h compared with control animals, followed by rapid clearanceover 4–8 h, in keeping with increased trafficking in thismodel. The increased trafficking was significantly reduced bydietary protein restriction with 4/6 Nx rats fed an 8% proteindiet exhibiting mesangial kinetics not significantly differentfrom control animals. Control animals exhibited identical kineticsirrespective of diet. In separate studies, the 8% protein diet significantly reducedproteinuria and glomerulosclerosis when compared with untreatedanimals when studied at 30 weeks postsurgery.