Interaction of monoamine oxidase inhibitory drugs with some phospholipids

The effect of 17 monoamine oxidase inhibitory drugs (propargylamine derivatives) on the phase transition parameters of some synthetic phospholipids has been studied by differential scanning calorimetry. The drugs modified the thermal behaviour of phospholipids proving the existence of phospholipid-drug interactions. Phosphatidylethanolamine, phosphatidylcholine and phosphatidic acid equally interact with the monoamine oxidase inhibitory drugs. Significant correlations were found between the change of the phase transition parameters of phospholipids and the hydrophilic and hydrophobic molecular parameters of drugs. Calculations suggest that both hydrophilic (between the head group of phospholipids and the polar propargylamine group of drugs) and hydrophobic (between 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 enhances considerably the strength of interaction.