Determination of histaminase (diamine oxidase) activity byo-dianisidine test: Interference of ceruloplasmin

Abstract

Until now o-dianisidine was used as an indicator substance in a test system for the determination of diamine oxidase. More recently, however, this substance was also used to measure ceruloplasmin activity. A study of the test principles revealed that o-dianisidine was the one denominator for both enzymes. As it was found for diamine oxidase the indicator was oxidized via peroxidase mediated H2O2 cleavage. Ceruloplasmin, however, oxidized o-dianisidine directly with resulting free radical formation. An addition of histamine dihydrochloride or putrescine dihydrochloride to an incubation mixture, containing ceruloplasmin as enzyme and o-dianisidine or p-phenylene-diamine as substrates, produced an activation of the enzyme, being more than 10-fold in the presence of 1 X 10(-2) M putrescine at pH 7.0. It was assumed that an allosteric effect of the dihydrochloride component might be responsible for this activation. When the activity of purified diamine oxidase was determined by the o-dianisidine test and by the isotope assay, a very good correlation between both methods was found. But, in a mixture of diamine oxidase and ceruloplasmin, no differentiation between the two enzymic activities by the o-dianisidine test was possible. This observation demonstrated an interference of ceruloplasmin when the o-dianisidine method was used for the determination of diamine oxidase activity. To apply our findings also in vivo the amine oxidase activity increasing in guinea-pig plasma during inflammation, was determined by the o-dianisidine test and by specific methods for some amine oxidase. Despite an enhanced oxidation of the o-dianisidine observed, only an increase of ceruloplasmin activity was found. It was concluded that ceruloplasmin had no 'histaminase activity' as has been assumed by other authors using the o-dianisidine test.

Ceruloplasmin and other copper binding components of blood plasma and their functions: an update

“…In vivo, the most likely physiological amine substrates are dopamine, 5-OH tryptamine (serotonin), epinephrine and nor-epinephrine, 50 but not histamine (although histamine does bind). 6,51 These amines are hormones or hormone precursors, and oxidation would result in their inactivation. As all hormone signals must be rapidly eliminated to prevent prolonged unregulated effects, it seems likely that Cp contributes to the inactivation of these natural bioactive amines.…”

Copper and ceruloplasmin (Cp) concentrations during the acute inflammatory process in the rat

“…BmGAr~SKI et al found an increase of plasma ceruloplasmin oxidase activity during experimental inflammation in guinea-pigs [18]. SCUDDER et al showed an increase of both ceruloplasmin (immunologically determined) and copper concentrations in the serum of rheumatoid patients and described the existence of a strong positive correlation between the two parameters [14].…”

“…Also in experimental models of inflammation an increase of serum copper concentration was repeatedly described as characteristic, regardless of the irritant and the animal species used. In particular, a rise of serum copper was measured after the injection of turpentine oil in rats [17], guinea-pigs [18], dogs [19] and rabbits [20] and after the injection of carrageenan [21] or Mycobacterium butyricum, suspended in liquid paraffin [22], in the rat.…”