Abstract
Total protein and deoxyribonucleic acid (dna) were measured in small-intestinal washings from rats with normal and high rates of dna (or cell) loss. There was a significant relationship between the loss of these two substances. Preparations of isolated viable epithelial cells contained much less protein in relation to dna than did the intestinal washings. It was calculated that only 8 to 15% of the protein lost by washing the rat small intestine arose from the intracellular protein of exfoliated epithelial cells. The rest was derived from extracellular sources.
Protein and dna loss from small-bowel mucosa was measured in six patients. The ratio of protein to dna was similar to that found in the rats. The mean protein loss from 5 cm of human upper small intestine was 956 μg per min or 1·4 g per 24 hours. By calculation, total protein loss from the whole small intestine of man was about 84 g per day, about 10 g coming from within exfoliated cells and the rest arising from extracellular sources. The normal intestine must reabsorb most of this material.
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Selected References
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- CROFT D. N., LUBRAN M. THE ESTIMATION OF DEOXYRIBONUCLEIC ACID IN THE PRESENCE OF SIALIC ACID: APPLICATION TO ANALYSIS OF HUMAN GASTRIC WASHINGS. Biochem J. 1965 Jun;95:612–620. doi: 10.1042/bj0950612. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Croft D. N., Ingelfinger F. J. Isolated gastric parietal cells: oxygen consumption, electrolyte content and intracellular pH. Clin Sci. 1969 Oct;37(2):491–501. [PubMed] [Google Scholar]
- HARRER D. S., STERN B. K., REILLY R. W. REMOVAL AND DISSOCIATION OF EPITHELIAL CELLS FROM THE RODENT GASTROINTESTINAL TRACT. Nature. 1964 Jul 18;203:319–320. doi: 10.1038/203319a0. [DOI] [PubMed] [Google Scholar]
- JEFFRIES G. H., HOLMAN H. R., SLEISENGER M. H. Plasma proteins and the gastrointestinal tract. N Engl J Med. 1962 Mar 29;266:652–660. doi: 10.1056/NEJM196203292661307. [DOI] [PubMed] [Google Scholar]
- KATZ J., ROSENFELD S., SELLERS A. L. Sites of plasma albumin catabolism in the rat. Am J Physiol. 1961 Jun;200:1301–1306. doi: 10.1152/ajplegacy.1961.200.6.1301. [DOI] [PubMed] [Google Scholar]
- Loehry C. A., Croft D. N., Singh A. K., Creamer B. Cell turnover in the rat small intestinal mucosa: an appraisal of cell loss. II. Cell loss in rats with an abnormal mucosa. Gut. 1969 Jan;10(1):16–18. doi: 10.1136/gut.10.1.16. [DOI] [PMC free article] [PubMed] [Google Scholar]
- NASSET E. S. THE ROLE OF THE DIGESTIVE TRACT IN PROTEIN METABOLISM. Am J Dig Dis. 1964 Mar;9:175–190. doi: 10.1007/BF02232581. [DOI] [PubMed] [Google Scholar]
- Nasset E. S. Role of the digestive system in protein metabolism. Fed Proc. 1965 Jul-Aug;24(4):953–958. [PubMed] [Google Scholar]
- PAPADOPOULOS N. M., HESS W. C., O'DOHERTY D., McLANE J. E. A procedure for the determination of cerebrospinal fluid total protein and gamma globulin in neurologic disorders. Clin Chem. 1959 Dec;5:569–574. [PubMed] [Google Scholar]
- PHILLIPS H. J., TERRYBERRY J. E. Counting actively metabolizing tissue cultured cells. Exp Cell Res. 1957 Oct;13(2):341–347. doi: 10.1016/0014-4827(57)90013-7. [DOI] [PubMed] [Google Scholar]
- Pink I. J., Croft D. N., Creamer B. Cell loss from small intestinal mucosa: a morphological study. Gut. 1970 Mar;11(3):217–222. doi: 10.1136/gut.11.3.217. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SYMONS L. E., FAIRBAIRN D. Pathology, absorption, transport, and activity of digestive enzymes in rat jejunum parasitized by the nematode Nippostrongylus brasiliensis. Fed Proc. 1962 Nov-Dec;21:913–918. [PubMed] [Google Scholar]
- WETTERFORS J., GULLBERG R., LILJEDAHL S. O., PLANTIN L. O., BIRKE G., OLHAGEN B. Role of the stomach and small intestine in albumin breakdown. Acta Med Scand. 1960 Nov 25;168:347–363. doi: 10.1111/j.0954-6820.1960.tb13456.x. [DOI] [PubMed] [Google Scholar]