INTERACTION OF MONOAMINE-OXIDASE INHIBITORY DRUGS WITH SOME PHOSPHOLIPIDS

The effect of 17 monoamine oxidase inhibitory drugs (propargylamine de rivatives) on the phase transition parameters of some synthetic phosph olipids has been studied by differential scanning calorimetry. The dru gs modified the thermal behaviour of phospholipids proving the existen ce of phospholipid-drug interactions. Phosphatidylethanolamine, phosph atidylcholine and phosphatidic acid equally interact with the monoamin e oxidase inhibitory drugs. Significant correlations were found betwee n the change of the phase transition parameters of phospholipids and t he hydrophilic and hydrophobic molecular parameters of drugs. Calculat ions suggest that both hydrophilic (between the head group of phosphol ipids and the polar propargylamine group of drugs) and hydrophobic (be tween the apolar fatty acid chains of phospholipids and the lipophilic substructures of drugs) forces are involved in the phospholipid-drug interaction. Chloro substitution in the hydrophobic moiety of drugs en hances considerably the strength of interaction.