STUDIES ON THE MECHANISM OF PROTEINURIA. (II)
OBSERVATION AND MEASUREMENT OF TUBULAR REABSORPTION RATE OF PROTEIN IN RENAL DISEASE
1958 Volume 47 Issue 6 Pages 599-620
Details
1958 Volume 47 Issue 6 Pages 599-620
The mechanism of tubular reabsorption rate of protein was functionally and morphologically studied and the following conclusions were obtained.
(1) It is considered that the reabsorbed protein in the proximal tubules are decomposed to polypeptides and amino-acids. The tubular reabsorbed protein calculated from arterio-venous α-amino-N difference by means of renal vein catheterization are average 33.6mg/min. in 5 normals, 22.2mg/min. in 4 acute nephritis, 7.3mg/min. in 7 chronic nephritis and 81.9mg/min. in the early stage of a nephrosis.
(2) The longer reduce of RPF produces more decrease in reabsorbed protein in the proximal tubules but the short term diminution of RPF in acute nephritis causes no marked decrease in reabsorbed protein.
In the early stage of nephrosis which shows no decrease in RPF, the increase in reabsorbed protein is accompanied with abnormal elevation of protein concentration in the glomerular filtrate.
(3) In the dog with proteinuria induced by the experimental injection of HgCl2, hemoglobin clearance is measured and it is evident that there is maximum amount of protein reabsorbtion in the tubules.
(4) Electron microscopic study on the tubular reabsorption of protein following the intravenous injection of hemoglobin indicates that the reabsorption of protein would be correlated with athrocytotic activity of protein utilization in apical cell zone, endoplasmic reticulum and palade granula.
