Small intestinal malabsorption of vitamin B(12) in iron-deficient rats.
Rats were rendered iron deficient by a combination of diet and bleeding to study its effects on vitamin B(12) absorption. Small intestinal loops were isolated in vivo and the absorption of -57Co-vitamin B(12) bound to a known quantity of intrinsic factor was measured. Iron deficiency resulted in the impairment of both uptake and transport of B(12). This malabsorption was corrected within 5 days by parenteral iron repletion. The findings were not due to a non-specific effect of anaemia since no correlation existed between haemoglobin levels and B(12) absorption in rats anaemic as a result of acute blood loss. No evidence was found for an altered small-intestinal microflora, bacterial counts being similar in iron-deficient and control rats. It is concluded that iron deficiency in the rat results in impaired absorption of B(12) by the small intestine, probably as a result of some defect produced in the enterocyte.
D000208:Acute Disease; D000747:Anemia, Hypochromic / Q000378:metabolism* / Q000382:microbiology / Q000503:physiopathology; D000818:Animals; D001419:Bacteria / Q000302:isolation & purification; D003037:Cobalt Radioisotopes; D005260:Female; D007408:Intestinal Absorption; D007421:Intestine, Small / Q000378:metabolism* / Q000382:microbiology; D007437:Intrinsic Factor / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D051381:Rats; D014805:Vitamin B 12 / Q000378:metabolism*
D003037:Cobalt Radioisotopes; D007437:Intrinsic Factor; D014805:Vitamin B 12