F1 and F2 of Najjar and Holt in the Urine of Normal Young Men 1

Abstract

Najjar and Holt (1,2) have demonstrated that their fluorescent urinary pigments, F1 and F2, are related to nicotinic acid metabolism in such a way that their estimation in urine is of diagnostic use in human pellagra (1) and in canine black tongue (1,2 assessing the nutritional status of young men (7), we have investigated the conditions under which the estimation of urinary F1 and F2 might be expected to yield useful information. In particular, we sought to answer 3 specific questions: first, whether the level of these pigments in urine in a post-absorptive state agrees with the criteria of Holt (3); second, whether their excretion following administration of nicotinamide correlates with other clinical data; and third, whether their excretion following the administration of various mixtures of vitamins has the same significance as after nicotinamide alone. Our observations have been limited solely to normal young men, and we have not studied pellagrins. EXPERIMENTALWe will discuss first, analytical methods; second, the stability of F2 in urine; and third, the F1 and F2 elimination of young men under a variety of conditions. Analytical methods All estimations of F1 and F2 reported in this paper were carried out by the method of Najjar and Wood (8) or by a modification of this method for rapid field use to be described in a forthcoming paper (7). This modification is different from the method of Huff and Perlzweig (9). In our determination, fluorometry was either photoelectric or visual and the reference standards were either quinine or thiochrome.Stability of F2 in urine Field surveys sometimes necessitate the collection of specimens in climatic extremes, transportation over considerable distances, and storage for various lengths of time before -analysis. The stability of F2 under simulated field conditions was therefore investigated. Random samples of urine were collected from several normal 714

Screening Tests for Urinary Uroporphyrin

“…(This removes almost all of the interfering substances from the talc without causing significant uroporphyrin loss.) 4. The porphyrins are eluted from the disk with 10 ml.…”