The Aging Change of Glycoconjugate Synthesis in Mouse Kidney Studied by 3H-Glucosamine Radioautography.

Abstract

The aging change of glycoconjugate synthesis in the mouse kidney was studied by light microscopic radioautography with 3H-glucosamine. The density of the silver grains was quantitatively analyzed over the renal corpuscles and uriniferous tubules in eight age groups from fetal day 19 to postnatal 1 year.As the results, all the cell types of the renal corpuscle, proximal and distal tubule of the nephron were labeled. The differences along with aging and among respective portions of the nephron were distinctive. The grain density of these three portions was shown to be generally in the following order in perinatal periods, from late fetal to early suckling: proximal tubule > distal tubule > renal corpuscle. The patterns of aging change of the grain density were similar among these three portions, i. e., the density was high in perinatal periods and then decreased with aging. The difference in the grain density was most remarkably observed between the perinatal periods and postnatal aged periods. The age-related change was remarkable in the proximal tubule as compared with the distal tubule and renal corpuscle.Glycoconjugate synthesis in mouse kidneywas shown to be more active in perinatal periods than postnatal aged periods, especially in the proximal tubule.