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. 1977 Jan;18(1):64–68. doi: 10.1136/gut.18.1.64

Significance of Ca-soap formation for calcium absorption in the rat.

G Gacs, D Barltrop
PMCID: PMC1411254  PMID: 838405

Abstract

The significance of calcium soap formation in the inhibition of calcium absorption has been studied in rats. 47Ca labelled soaps of fatty acids were introduced into the duodenum and the absorption of calcium measured after four hours in a whole body counter. The absorption of calcium was inversely correlated with the chain length of the fatty acid varying from 1% for Ca-stearate to 60% for Ca-hexanoate. Increasing the degree of unsaturation of the fatty acid was accompanied by increased calcium absorption. The availability of calcium for absorption from the soaps was correlated with their solubility in 1% aqueous Na-tauroglycocholate. The percentages of calcium as soap in the small intestine and the faeces after intragastric administration of calcium and fats were similar, which suggests that the faecal content of calcium soaps is an index of intestinal soap formation. Soap formation was negligible when CaCl2 was given with tristearate, triolaeate, or tridecanoate and no depression of calcium absorption was observed. Calcium absorption was markedly impaired by the addition of phosphates at a Ca/P ratio of 1:1 irrespective of the presence of neutral fats. Stearic acid resulted in significant soap formation and reduced calcium absorption. The degree of Ca-soap formation and the inhibition of calcium absorption were well correlated. The results suggest that, although calcium soap formation may markedly depress calcium absorption in the rat, no significant soap formation takes place when fats are given in the form of triglycerides.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Agnew J. E., Holdsworth C. D. The effect of fat on calcium absorption from a mixed meal in normal subjects, patients with malabsorptive disease, and patients with a partial gastrectomy. Gut. 1971 Dec;12(12):973–977. doi: 10.1136/gut.12.12.973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Barltrop D., Oppé T. E. Absorption of fat and calcium by low birthweight infants from milks containing butterfat and olive oil. Arch Dis Child. 1973 Jul;48(7):496–501. doi: 10.1136/adc.48.7.496. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Barltrop D., Oppé T. E. Dietary factors in neonatal calcium homoeostasis. Lancet. 1970 Dec 26;2(7687):1333–1335. doi: 10.1016/s0140-6736(70)92359-7. [DOI] [PubMed] [Google Scholar]
  4. Harrison J. E., McHattie J. D., Ligon I. R., Jeejeebhoy K. N., Finlay J. M. Effect of medium chain triglyceride on fecal calcium losses in pancreatic insufficiency. Clin Biochem. 1973 Jun;6(2):136–140. doi: 10.1016/s0009-9120(73)80023-2. [DOI] [PubMed] [Google Scholar]
  5. Kehayoglou A. K., Holdsworth C. D., Agnew J. E., Whelton M. J., Sherlock S. Bone disease and calcium absorption in primary biliary cirrhosis with special reference to vitamin-D therapy. Lancet. 1968 Apr 6;1(7545):715–718. doi: 10.1016/s0140-6736(68)92164-8. [DOI] [PubMed] [Google Scholar]
  6. Kehayoglou A. K., Williams H. S., Whimster W. F., Holdsworth C. D. Calcium absorption in the normal, bile-duct ligated, and cirrhotic rat, with observations on the effect of long- and medium-chain triglycerides. Gut. 1968 Oct;9(5):597–603. doi: 10.1136/gut.9.5.597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kehayoglou K., Hadziyannis S., Kostamis P., Malamos B. The effect of medium-chain triglyceride on 47 calcium absorption in patients with primary biliary cirrhosis. Gut. 1973 Aug;14(8):653–656. doi: 10.1136/gut.14.8.653. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. SAMMONS H. G., WIGGS S. M. The separation, estimation and analysis of calcium soaps in human faeces. Clin Chim Acta. 1960 Jan;5:141–145. doi: 10.1016/0009-8981(60)90101-7. [DOI] [PubMed] [Google Scholar]
  9. STEGGERDA F. R., MITCHELL H. H. The calcium balance of adult human subjects on high- and low-fat (butter) diets. J Nutr. 1951 Oct;45(2):201–211. doi: 10.1093/jn/45.2.201. [DOI] [PubMed] [Google Scholar]
  10. Tadayyon B., Lutwak L. Interrelationship of triglycerides with calcium, magnesium and phosphorus in the rat. J Nutr. 1969 Feb;97(2):246–254. doi: 10.1093/jn/97.2.246. [DOI] [PubMed] [Google Scholar]
  11. Widdowson E. M. Absorption and excretion of fat, nitrogen, and minerals from "filled" milks by babies one week old. Lancet. 1965 Nov 27;2(7422):1099–1105. doi: 10.1016/s0140-6736(65)90065-6. [DOI] [PubMed] [Google Scholar]
  12. Williams M. L., Rose C. S., Morrow G., 3rd, Sloan S. E., Barness L. A. Calcium and fat absorption in neonatal period. Am J Clin Nutr. 1970 Oct;23(10):1322–1330. doi: 10.1093/ajcn/23.10.1322. [DOI] [PubMed] [Google Scholar]

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