Effect of Vitamin B₁₂ Deficiency on Liver Dehydrogenase Activity in Rats

Abstract

WEANLING rats born of mothers maintained on a diet deficient in vitamin B₁₂ during pregnancy were fed on a vitamin B₁₂-free ration for twelve weeks and their liver dehydrogenase levels were compared with those of similar animals receiving 2-µgm. supplements of vitamin B₁₂ daily. The basal diet had the composition : whole soya bean flour, 25; groundnut cake flour, 14; sesame cake flour, 14; wheat flour, 14; rice flour, 14; Bengal gram flour, 14; vitaminized starch, 2 (containing adequate quantities of all B-complex vitamins except vitamin B₁₂); shark liver oil, 2; Osborne and Mendel salt mixture, 1. At the end of the experiment, the animals were killed and the excised livers freed of blood clots and immediately chilled and used for measurement of dehydrogenase activities. Liver homogenates prepared in ice-cold M/15 phosphate buffer of pH 7.2 were used for the measurement of lactic, glutamic, succinic, butyric and choline dehydrogenase activities, according to the method described by Sreenivasa Murthy and Swaminathan¹, using tetrazolium bromide as the hydrogen acceptor. Portions of the liver tissue were used for nitrogen estimation by the Kjeldahl method. The vitamin B₁₂ content of the liver was measured microbiologically using L. leichmannii-4797 as the test organism.