Abstract
In gut mucosa of the rat and the mouse, succinic dehydrogenase and xanthine oxidase, especially the former, were strongly affected by riboflavin deficiency, while no influence was observed on DPNH-diaphorase actvity. On the basis of these results it is assumed that DPNH-diaphorase might be related to division of the epithelial cells of gut mucosa, since the enzymatic activity was not decreased by riboflavin restriction on gut mucosa where formation and decomposition of the enzyme would be accompanied with those of the epithelial cells. We further postulated that some symptoms of ariboflavinosis might be related to decrease of succinic dehydrogenase activity.
