Metabolism of sulfadimidine, sulfanilamide, p-aminobenzoic acid, and isoniazid in suspensions of parenchymal and nonparenchymal rat liver cells.

Suspensions of isolated liver cells were prepared from rat livers perfused with Ca++-free buffer and 0.05% collagenase. Primary cell suspensions (containing both parenchymal and nonparenchymal liver cells) metabolized sulfadimidine, sulfanilamide, p-aminobenzoic acid, and isoniazid approximately at first order kinetics for at least 4 hr. Suspensions of parenchymal cells had the same metabolic capacity, although the metabolism of isoniazid proceeded at a somewhat reduced rate compared to the primary cell suspensions. Suspensions of nonparenchymal cells did not metabolize sulfadimidine, sulfanilamide, or p-aminobenzoic acid during 4 hr, although such suspensions acted upon isoniazid to some degree. It was concluded that parenchymal rat liver cells may metabolize (acetylate) all four drugs tested, whereas nonparenchymal cells metabolize only isoniazid to any considerable extent.