In this paper the physiological criteria for a novel form of model are described whose biokinetics are governed by the overall metabolic reactions of the principal nutrients: @entity3363 , @entity10392 , and proteins. The biokinetics of a particular element are based primarily on the oxidation of @entity413 , @entity1718 , and @entity1522 and the formation of water, @entity544 , and @entity1133 . The compartmental models proposed follow the pathways of the major elements including @entity3884 and, hence, @entity4463 . The parameters for two models of differing complexity--called the @entity65137 -S and @entity65137 -C models--were evaluated here on the basis of biochemical reactions; the results of compartmental analysis are reported in an accompanying paper. The simpler form of the @entity65137 model has single compartments representing the principal nutrients. The more complex model includes compartments representing the longer-term retention of @entity3363 as glycogen, @entity10392 as adipose tissue, and proteins in bone and soft tissues. The pool sizes and @entity3884 transfer rates are estimated. The incorporation of biochemical reactions and important metabolic parameters serve to give the models a greater semblance of physiological merit than those currently available. For example, ingestion of @entity3363 results in a respiratory quotient of 1.0 and 100% of the @entity3884 content oxidized to water, which are the same as values published in the literature. This form of metabolic model enables development of models for other isotopes, besides 3H, of the major elements of the body, e.g., 14C, @entity13140 , @entity14682 .

A biochemical-based model for the dosimetry of dietary organically bound XXXX --Part 1: Physiological criteria.

@entity1522 :: ('CHEBI:33709', 'Chemical') :: ['amino acids'] @entity3884 :: ('MESH:D006859', 'Chemical') :: ['hydrogen'] @entity3363 :: ('MESH:D002241', 'Chemical') :: ['carbohydrates'] @entity1133 :: ('MESH:D014508', 'Chemical') :: ['urea'] @entity14682 :: ('CHEBI:33815', 'Chemical') :: ['18O'] @entity65137 :: ('CHEBI:22307', 'Chemical') :: ['HCNO'] @entity4463 :: ('CHEBI:29304', 'Chemical') :: ['tritium'] @entity10392 :: ('118611', 'Gene') :: ['fats'] @entity544 :: ('MESH:D002245', 'Chemical') :: ['carbon dioxide'] @entity1718 :: ('MESH:D005227', 'Chemical') :: ['fatty acids'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose'] @entity13140 :: ('CHEBI:36934', 'Chemical') :: ['15N']
@entity4463 :: (CHEBI:29304,Chemical) :: ['tritium']
