Renal glucuronidation of morphine in the human foetus

The glucuronidation of morphine was investigated in kidney microsomes from human foetuses. This reaction was found to be catalyzed in all specimens investigated and the UDP-glucuronyltransferase activities varied between 0.18 and 0.30 nmol per min. per mg microsomal protein. Intraindividual comparisons with the hepatic glucuronidation rates revealed the renal enzyme rate to be about 50 percent of the hepatic. Oxazepam, and to a lesser extent salicylamide, inhibited the glucuronidation of morphine in kidney microsomes in similarity to what previously was shown in human foetal liver microsomes.