The Enzymatic Deacetylation of Heroin and Related Morphine Derivatives by Blood Serum

Abstract

The blood sera of rabbits contain an enzyme or enzymes which catalyze the deacetylation of some acetylated derivatives of morphine. The sera are readily divisible into two classes based on their deacetylating ability. One class removed both acetyl radicals from diacetylmorphine, deacetylated monoacetylmorphine and removed the phenolic acetyl from diacetyldihydromorphine. The other class removed only the phenolic acetyl from diacetylmorphine, did not deacetylate monoacetylmorphine and only slowly removed the phenolic acetyl from diacetyldihydromorphine. None of the sera was able to remove the alcoholic acetyl radical from monoacetyldihydromorphine. The bearing of the presence of the deacetylating enzymes on the problem of the varying potency of the morphine derivatives and the question of relationship to cholinesterase is discussed.