CHARACTERIZATION OF MONOOXYGENASE SYSTEM IN CHINESE FETAL ADRENAL-GLAND

The characteristics of the monooxygenase system were studied in chines e fetal adrenal gland. Substantial P450 was present in varying but sig nificant concentration in all fetal adrenals (0.295 +/- 0.239 nmol mg( -1) protein). P450 content showed an increasing trend at mid gestation (r = 0.9987, p < 0.01). The rates of metabolism of aminopyrine (AM) a nd aniline (AN) per min per mg protein in the microsomal fraction were 0.259 +/- 0.155 and 0.096 +/- 0.041, respectively, and the enzyme act ivities did not vary significantly with fetal sex. NADPH-cytochrome C reductase. AM demethylase and AN hydroxylase activity in fetal adrenal microsome was 534%, 135% and 436%, respectively, of the fetal liver. The present study suggests that adrenal gland may also serve as an imp ortant drug-metabolizing organ in human fetus.