The urinary excretory ratio of nicotinamide catabolites was associated with the conversion ratio of tryptophan to nicotinamide in growing rats fed a niacin-free 20% casein diet.
Weaning rats were fed a niacin-free 20% casein diet. Twenty-four-h-urine samples were collected, and nicotinamide and its catabolites were measured. A correlation was found between the urinary excretory ratio of nicotinamide catabolites (N(1)-methyl-2-pyridone-5-carboxamide + N(1)-methyl-4-pyridone-3-carboxamide)/N(1)-methylnicotinamide and the tryptophan-nicotinamide conversion ratio during growing period of the rats. This indicates the possibility that the conversion ratio can be deduced from the excretory ratio.
Department of Food Science and Nutrition, School of Human Cultures, The University of Shiga Prefecture, Hikone, Shiga, Japan. kshibata@shc.usp.ac.jp
Katsumi
K
Shibata
Eri
E
Imai
Mitsue
M
Sano
Tsutomu
T
Fukuwatari
D000818:Animals; D002364:Caseins / Q000737:chemistry*; D004032:Diet; D008297:Male; D009525:Niacin; D009536:Niacinamide / Q000378:metabolism* / Q000652:urine*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014364:Tryptophan / Q000378:metabolism*
D002364:Caseins; D009536:Niacinamide; D009525:Niacin; D014364:Tryptophan