Size of dose and acetylation of aromatic amines in the rat.

Pantothenic acid, a portion of the coenzyme A molecule (l), must be supplied in the diet for normal acetylation of p-aminobenzoic acid (PAB) (2) and of sulfanilamide (3) by the rat. Only at certain test levels of PAB, however, is pantothenate deficiency reflected by decreased acetylation (4). The present communication extends the study of the relation between acetylation and size of dose over a wide range and emphasizes the necessity of selecting the dosage of a test substance in relation to the body weight of the animal. The onset of pantothenate deficiency as measured by decreased acetylation has also been shown to vary greatly with the size of the rat.