Induction and quail liver diamine oxidase (histaminase). Part II: Different responses to the inducers.

In quail liver microsomes the metabolism of histamine is prevalently sustained by diaminoxidase (DAO). Treatment with phenobarbital (PB) and clofibrate (CF) does not modify DAO activity, while that with Aroclor 1254 (PCB) and beta-naphtoflavone (BNF) significantly decreases it. The decrease of DAO activity produced by these substances is not dependent on their direct inhibition of the enzyme. DAO decrease might represent a further possibility to discriminate among different inducers; moreover, it implies that histamine metabolism might be decreased, in quail liver, by some classes of inducers.