In vitro inhibition of human platelet monoamine oxidase by phenothiazine derivatives.
Nineteen phenothiazines were tested for in vitro inhibition of human platelet type B monoamine oxidase (MAO). The inhibition potency was highly dependent on structures of their side chains. The inhibition was most potent for drugs with (hydroxyethyl-piperazinyl)propyl chains followed in decreasing order by those with (N-methylpiperazinyl)propyl, (2-dimethylamino-2-methyl)ethyl and 3-dimethylaminopropyl chains. Kinetic analyses were carried out for promazine, promethazine, perazine and perphenazine as representatives of each group; the four drugs showed competitive inhibition, and Ki values of 124, 31.4, 19.2 and 22.6 microM, respectively.
Suzuki
O
O
Department of Legal Medicine, Hamamatsu University School of Medicine, Japan.
Seno
H
H
Kumazawa
T
T
D001792:Blood Platelets / Q000293:injuries*; D006801:Humans; D066298:In Vitro Techniques; D008995:Monoamine Oxidase / Q000378:metabolism*; D010464:Perazine / Q000493:pharmacokinetics; D010546:Perphenazine / Q000493:pharmacokinetics; D010640:Phenothiazines / Q000493:pharmacokinetics*; D011395:Promazine / Q000493:pharmacokinetics; D011398:Promethazine / Q000493:pharmacokinetics
D010640:Phenothiazines; D010464:Perazine; D008995:Monoamine Oxidase; D011398:Promethazine; D010546:Perphenazine; D011395:Promazine