A Study of the Nitrogen Metabolism of Lysine-Deficient Rats

Abstract

The effects of a lysine deficiency upon nitrogen balance and nitrogen components of the blood and urine have been investigated employing both ad libitum and force-feeding procedures. Under force-feeding conditions a marked increase was noted in urinary nitrogen for animals receiving a lysine-deficient ration. The extra nitrogen was identified as almost entirely urea. As in previous studies, a positive nitrogen balance was obtained throughout the experiment for animals force-fed the lysine-deficient ration. Blood nitrogen could not account for this retained nitrogen. Uremia could not account for the death of the animals from a lysine deficiency as shown by measurement of various nitrogen components as well as the total nitrogen of the blood.