Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pepsinogen A (PGA) and pepsinogen C (PGC) are negatively charged, low molecular weight (LMW) proteins with a striking difference in renal handling: PGA (molecular weight 43,500 daltons) shows a high fractional excretion while the fractional excretion of PGC (molecular weight 40,500 daltons) is low, presumably due to tubular reabsorption. As these data suggest a high glomerular sieving of pepsinogens, we assessed the glomerular sieving coefficient (GSC) of PGA, PGC and several other proteins from their renal extractions. For this purpose blood samples were obtained simultaneously from the aorta (A) and right renal vein (V) in nine patients undergoing an elective heart catheterization. After correction of A-V differences for diuresis with the A-V difference of transferrin, GSCs (+/- SEM) for PGA and PGC were 0.90 +/- 0.14 and 0.85 +/- 0.17, respectively, GSC of beta 2-microglobulin being 0.90 +/- 0.12. For albumin and IgG, known to have a low GSC, low values were found. It is concluded that the GSC of a LMW protein in man can be calculated from both its A-V difference over the kidney and the A-V difference of an inert marker with a GSC of 1, provided they are corrected by the A-V difference of an inert marker with a GSC of 0. Our results demonstrate that PGA and PGC are almost freely filtered through the glomerular basement membrane despite their size and negative net molecular charge.
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PMID:The glomerular sieving of pepsinogen A and C in man. 247 70

Pepsinogen A (PGA) and pepsinogen C (PGC) are low-molecular-weight proteins synthesized by the gastric mucosa. Data in man suggest that both pepsinogens are almost freely filtered through the glomerular basement membrane despite a molecular weight of about 43,000 dalton and a strongly negative charge. This promoted us to investigate the glomerular sieving of PGA and PGC in the isolated rat kidney model by measuring their fractional excretions before and after inhibition of tubular function with sodium iodoacetate. During the control episode fractional excretion of PGA was 40 +/- 0.04% and of PGC 42 +/- 0.04% (mean +/- SEM from 9 experiments). After complete inhibition of tubular function a large increase in fractional excretion was found for both pepsinogens: 87 +/- 0.04% for PGA and 95 +/- 0.09% for PGC. It is concluded that tubular secretion does not contribute to the high fractional excretion of pepsinogens and that both PGA and PGC are almost freely filtered through the glomerular basement membrane.
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PMID:Handling of human pepsinogens by the isolated rat kidney: evidence for a high glomerular sieving coefficient. 272 83