A phenotypic study of nacetyltransferase1 (nat1) in local human population for determination of nacetyl metabolite of 5-aminosalicylic acid

N-acetyletransferase-1 (nat1) is the phase ii metabolizing enzyme,renders for the detoxification of many drugs and arylamines present in foods. nat1 is polymorphic in nature,varies in different ethnic groups. the present study was designed to evaluate the acetylation capacity of nat1 using 5-aminosalicyclic acid in the healthy pakistani population. the blood samples were collected at 3 hour from each volunteer for acetyl metabolites. the concentrations of acetyl metabolite and parent drug were determined in plasma samples by hplc. the concentrations of 5-aminosalicyclic acid (5-asa),acetyl 5-aminosalicyclic acid (ac5-asa),ratio of ac5-asa/5-asa were determined to assign the population into slow or fast acetylators by using the statistical model probit plot. nat1 acetylation activity by 5-asa showed bimodal frequency distribution in the population. almost 71% of the population was fast acetylator and 29% was slow acetylator.