Focal glomerulosclerosis in obese zucker rats and prevention of its development

Genetically obese Zucker rats develop a spontaneous glomerular disease. The mechanism of development of this lesion is poorly understood. We therefore examined structural alterations of the kidneys by light microscopy and by use of nephron dissection technique. The glomerular lesion was a focal segmental sclerosis that developed in association with glomerular enlargement and with prominent dilation of collecting and connecting tubular lumina. Reduction of dietary intake in these obese rats prevented the emergence of glomerulomegaly, glomerulosclerosis, and tubular dilation. The development of the glomerulosclerosis might be related to glomerulomegaly. In addition, the prominent dilation of collecting and connecting tubules without evidence of obstruction of lower urinary tract indicated that there was intrarenal tubular obstruction.