TY - JOUR
T1 - Glomerular filtration of proteins
T2 - Clearance of anionic, neutral, and cationic horseradish peroxidase in the rat
AU - Rennke, H. G.
AU - Patel, Y.
AU - Venkatachalam, M. A.
N1 - Funding Information:
Part of this work was presented at the regional meeting of the American Federation for Clinical Research, Boston, Massachusetts, January, 1977. This work was supported in part by the National Institutes of Health Grant AM 16749 and General Research Grant RR 05489. Dr. Rennke is the recipi- ent of a fellowship award from the Massachusetts
PY - 1978
Y1 - 1978
N2 - Glomerular permeability to horseradish peroxidase, a protein slightly smaller than rat albumin but similar in shape, was studied in Wistar-Furth rats by using a purified neutral isozyme (HRP; molecular radius, a(e) = 29.8 Ȧ) as well as an anionic succinyl-derivative (sHRP a(e) = 31.8 Ȧ) and a cationized enzyme (cHRP, a(e) = 30 Ȧ). The clearance rate of the proteins was determined over a 20-min period using the amounts of enzyme actually filtered (i.e., protein in the urine and protein reabsorbed by tubules). Fractional clearance of cationic HRP (0.338 ± 0.019) exceeded that of neutral HRP (0.061 ± 0.005) by a factor of 5.5 and that of anionic HRP (0.007 ± 0.000) by a factor of 48. Tubular reabsorption was less than 10% of the filtered load. The experimental results indicate marked charge dependency of the filtration of proteins across the glomerulus. Fractional clearances for these proteins are significantly lower than those reported in the literature for dextrans of similar molecular radii. Other molecular properties such as shape and deformability may explain these differences.
AB - Glomerular permeability to horseradish peroxidase, a protein slightly smaller than rat albumin but similar in shape, was studied in Wistar-Furth rats by using a purified neutral isozyme (HRP; molecular radius, a(e) = 29.8 Ȧ) as well as an anionic succinyl-derivative (sHRP a(e) = 31.8 Ȧ) and a cationized enzyme (cHRP, a(e) = 30 Ȧ). The clearance rate of the proteins was determined over a 20-min period using the amounts of enzyme actually filtered (i.e., protein in the urine and protein reabsorbed by tubules). Fractional clearance of cationic HRP (0.338 ± 0.019) exceeded that of neutral HRP (0.061 ± 0.005) by a factor of 5.5 and that of anionic HRP (0.007 ± 0.000) by a factor of 48. Tubular reabsorption was less than 10% of the filtered load. The experimental results indicate marked charge dependency of the filtration of proteins across the glomerulus. Fractional clearances for these proteins are significantly lower than those reported in the literature for dextrans of similar molecular radii. Other molecular properties such as shape and deformability may explain these differences.
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U2 - 10.1038/ki.1978.41
DO - 10.1038/ki.1978.41
M3 - Article
C2 - 651127
AN - SCOPUS:0018147284
SN - 0085-2538
VL - 13
SP - 278
EP - 288
JO - Kidney international
JF - Kidney international
IS - 4
ER -