Glomerular sclerosis in Wistar rats: analysis of its variable occurrence after unilateral nephrectomy.

Individual differences in susceptibility to the development of focal and segmental glomerular hyalinosis and sclerosis (FSGHS) were studied in rats after unilateral nephrectomy. A total of 20 male Wistar rats underwent unilateral nephrectomy at 3 months of age. Glomerular number in the removed kidney ranged from 17,000 to 32,700 with a mean value of 25,997 (n = 19). At death 30 weeks later, the incidence of glomeruli with FSGHS in the remaining kidney varied from 0 to 20% with a mean of 4.4%. However, the percentage of glomeruli with FSGHS and the degree of proteinuria did not correlate either with glomerular number per kidney (left and right kidneys were shown to be equivalent for glomerular number) or with glomerular volume on killing. The occurrence of FSGHS correlated significantly with mean protein excretion (P less than 0.01) and serum cholesterol levels (P less than 0.01). In conclusion, in the rat a relatively low number of nephrons in the kidneys does not increase susceptibility to the development of FSGHS.