Monooxygenase activity of human liver in microsomal fractions of needle biopsy specimens.

1 Methods are described for the determination of mixed function oxidase activity in microsomal fractions from percutaneous needle biopsies of human liver. 2 Activities of needle biopsy samples were comparable with those of wedge biopsy sample obtained at laparotomy from different subjects. 3 Although cytochrome P-450 content of liver from rat and man was similar, human AHH activity was only 10% of that in the rat. 4 In biopsies with preserved hepatic architecture, AHH activity and cytochrome P-450 content showed a significant positive correlation. 5 Cigarette smoking significantly increased both AHH activity and turnover number, but not cytochrome P-450 content, of biopsies with normal architecture. 6 The presence of liver disease caused a significant decrease in AHH activity and cytochrome P-450 content.