抄録
Proximal convoluted tubules in the kidneys from eighteen patients with chronic glomerulonephritis were studied by light and electron microscopy. Nine of these had been treated with hemodialysis. Besides, proximal convoluted tubules at urinary poles of variously affected glomeruli were pursued by using serial sections, in order to clarify the interrelation between morphologic changes of proximal convoluted tubules and those of glomeruli. Grade of atrophy of proximal convoluted tubule generally increased in proportion to damage of parent glomerulus. Proximal convoluted tubules belonging to obsolescent glomeruli were severely atrophic and showed markedly thickened basement membranes. Moreover, proximal convoluted tubules arising from obsolescent glomeruli which were in resorption stage had often disappeared, or showed remnants of fragmentary thickened basement membranes without epithelial cells. It was suggested that atrophy of proximal convoluted tubule progressed in association with evolution of glomerulitis, and finally the atrophic proximal convoluted tubule disintegrated and disappeared. Ultrastructural study of the atrophic proximal convoluted tubules revealed marked decrease in number and length of microvilli, disappearance of lateral and basal interdigita-tions between adjacent cells, almost smooth contour of lateral cell membrane, pronounced small basal cytoplasmic processes, and severe thickening of basement membrane with massive cellular debris. These debris might be originated from such basal cytoplasmic processes of epithelial cells or slender extentions of fibroblasts existing at peripheral part of thickened basement membrane. In this paper three subjects have been discussed: first is the interrelations between morphologic changes of proximal convoluted tubules and those of glomeruli, second is the difference between changes of the proximal convoluted tubules in non-dialyzed kidneys and those in dialyzed ones, and third is disintegration and disappearance process of the atrophic proximal convoluted tubules.
