INTERINDIVIDUAL VARIABILITY OF PHENOL-SULFOTRANSFERASES AND CATECHOL-SULFOTRANSFERASES IN PLATELETS FROM ADULTS AND NEWBORNS

1 Phenol- and catechol- sulphotransferase activities were measured wit h p-nitrophenol and dopamine as substrates in platelets obtained from 100 newborns and 100 healthy adults. 2 Mean +/- (s.d.) estimates of ca techol sulphotransferase activity were 7.07 +/- 5.93 (adult) and 13.3 +/- 6.42 (newborn) pmol min-1 mg-1 protein, respectively (P < 0.001). The coefficients of variation were 84% (adult) and 48% (newborn). The frequency distribution of sulphotransferase activity was symmetric and did not deviate significantly from normality in newborn platelets, bu t was positively skewed in adult platelets. 3 Mean +/- (s.d.) estimate s of phenol sulphotransferase activity were 3.01 +/- 3.21 (adult) and 4.80 +/- 4.34 (newborn) pmol min-1 mg-1, respectively (P < 0.001). The coefficients of variation were 107% (adult) and 90% (newborn). The fr equency distribution of sulphotransferase activity was positively skew ed in both newborn and adult platelets. 4 Since sulphotransferase acti vity in platelets is well-expressed at birth and a prenatal developmen t of sulphotransferase has been described in mid-gestational human foe tal liver, the newborn should be able to sulphate drugs.