Renal tubular transport and catabolism of proteins and peptides
| Autor: | Theodore N. Pullman, Suzanne Oparil, Frank A. Carone, D. R. Peterson |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
chemistry.chemical_classification
Brush border Catabolism Reabsorption Tubular fluid Proteins Biological Transport Vacuole Metabolism Endocytosis Rats Amino acid Kidney Tubules Proximal Microscopy Electron Dogs Kidney Tubules Biochemistry chemistry Nephrology Animals Autoradiography Kidney Tubules Collecting Kidney Tubules Distal Peptides |
| Zdroj: | Kidney International. 16:271-278 |
| ISSN: | 0085-2538 |
| DOI: | 10.1038/ki.1979.129 |
| Popis: | It is established that the kidney plays an important role in the metabolism of a number of protein, polypeptide, and small peptide molecules, including plasma proteins, growth hormone,L-chains of immunoglobulins, β2-microglobulin, lysozyme, insulin, proinsulin, parathyroid hormone, glucagon, and small vasoactive peptides. Absorption, transport, and/or degradation of proteins or peptides are functions of the proximal tubule; there is little evidence that other segments of the nephron have the mechanisms for uptake or transport of these substances. Indirect and direct studies indicate that a variety of proteins and polypeptides filtered at the glomerulus are absorbed by the proximal tubule by luminal endocytosis and hydrolyzed by lysosomal enzymes. Our recent studies suggest that small linear peptides, consisting of eight to ten amino acids, are handled by the proximal tubule by a different mechanism. We have demonstrated that small linear peptides microinfused into proximal tubules are hydrolyzed at the luminal surface of the brush border, which is rich in a variety of enzymes, by the process of membrane or contact digestion with reabsorption of most of the breakdown products. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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