Nephrotoxicity and Studies on the Reabsorption and Disposal of Alpha 2U-Globulin
Alpha-2u-globulin, a low-molecular weight (LMW) protein of 19,000 dalton, is synthesised by the male rat liver as a family of isoforms; pI = 4.6–5.2. This protein is an important constituent of the physiological proteinuria in adult male rats. At maturity the total urinary protein is 20–30% alpha-2u and 10% albumin. At 160 days of age the excretion of albumin and total urinary proteins are markedly increased. By one year, albumin represents nearly 60% of the total protein while alpha-2u is less than 10%. This reversal in relative content may be the consequence of a progressive glomerulonephrosis, associated with an apparent spontaneous accumulation of hyaline droplets. The nephrotic condition may be the consequence of the burden of excreting alpha-2u. Its early onset is sexdependent; female rats do not exhibit the proteinuria until a later age.
KeywordsAlbumin Sodium Chloride Hydrocarbon Carboxyl Lysine
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