Small intestinal malabsorption of vitamin B12 in iron-deficient rats

Abstract

Rats were rendered iron deficient by a combination of diet and bleeding to study its effects on vitamin B12 absorption. Small intestinal loops were isolated in vivo and the absorption of57Co-vitamin B12 bound to a known quantity of intrinsic factor was measured. Iron deficiency resulted in the impairment of both uptake and transport of B12. 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 B12 absorption in rats anaemic as a result of acute blood loss. No evidence was found for an altered small-intestinal microflora, bacterial counts being simil..