Breakdown of Urea in the Rat

Abstract

With the aid of urea-Cl4 it was shown the urea suffered a rapid breakdown in the normal intact adult rat, so that 20-40% of the C14 appeared in the respiratory gas in 24 hrs. Much less breakdown was observed in an eviscerated rat and in one treated with succinyl sulfa-thiazole. In vitro it was found that neither liver, kidney nor intestinal slices broke down urea rapidly but that the opposite was true for intestinal washings. Thus it appears that the major part of the urea breakdown which occurred in the intact rats was due to the activity of the intestinal flora. A continual cycle of urea breakdown and synthesis occurred in the animals.