Piracetam-induced Changes To Membrane Physical-properties - a Combined Approach By P-31 Nuclear-magnetic-resonance and Conformational-analysis

Piracetam, Nootropil(R) (2-oxo-1-pyrrolidine acetamide), is a drug promoting erythrocyte deformability. To establish the mode of action of this compound, we have investigated its influence on the organization of model phospholipid membranes. P-31 NMR data show that the drug induces a structural modification in liposomes made of phosphatidylcholine and phosphatidylethanolamine. Our conformational analysis results have allowed the interpretation of the effect of piracetam on these model membranes: the specific interaction between the drug molecules and the phosphate headgroups induces a new organization of the lipids favouring formation of mobile drug-phospholipid complexes that exhibit an isotropic-type signal in the P-31 NMR spectra.