[Localization of N-acetyltransferases in sinusoidal liver cells. Effect of zymosan on the acetylation of sulfamethazine and isoniazid in the rat and in isolated perfused liver].

N-acetyltransferase (NAT) have been demonstrated to be localized in sinusoïdal cells and not in hepatocytes. Acetylation activities increased after pretreatment with Zymosan (40 mg/kg, i.v., 24 h before phenotyping) as well in vivo and in isolated perfused liver and in cytosolic fractions prepared from several rats organs. These data favor the localization of NAT-activity in reticulo-endothelial system. Increased protein levels in liver, gut, spleen and lungs cytosolic fractions (100 000 g, 120 mn) 48 h after Zymosan administration, suggest and inducing effect of this drug on NAT activity.