EFFECTS OF A VITAMIN Blz DEFICIENCY ON LIVER ENZYMES IN THE RAT*

Certain general functions of vitamin Blz and folic acid in intermediary metabolism are now well recognized. For example, folic acid appears to be involved in purine and formate metabolism and vitamin Blz in the utilization of methyl groups. However, while there have been several reports concerning the influence in viva and in vitro of folic acid and its antagonist, aminopterin, on specific enzyme systems such as xanthine oxidase (l-4), choline oxidase (58), and transmethylase (9, lo), there is scant information on the effects of dietary vitamin Blz on these or other enzyme systems. In the course of work on the biological action in the rat of a reported specific antagonist to vitamin Blz for Lactobacillus leichmannii 4797 (ll), the authors have undertaken a study of the effects of this antagonist as well as of simple vitamin Blz deficiency on certain enzyme systems in the rat. The liver enzymes chosen for study, transmethylase, xanthine oxidase, endogenous respiration, and choline oxidase, have been implicated indirectly by various workers with vitamin Blz metabolism. These investigations should throw some light on the involvement of vitamin Blz with specific enzyme systems. In addition, the effects of the L. leichrnannii antagonist can be compared with a simple vitamin Blz deficiency in the rat.