EFFECT OF N-ACYLETHANOLAMINES WITH DIFFERENT ACYL-CHAINS ON DPPC MULTILAMELLAR LIPOSOMES

The influence of N-acylethanolamines with different acyl-chains on the physico-chemical state of neutral phospholipids was investigated usin g dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes. The thermal dependence of steady state fluorescence anisotropy of 1,6-diph enyl-1,3,5-hexatriene (DPH) and its charged derivative (4-trimethylami nophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) was recorded. The N-acyl ethanolamines modified the DPPC phase transition temperature and broad ened the transition temperature range in different ways depending on t he N-acylethanolamines acyl chain characteristics. Our data suggest th at the N-acylethanolamine acyl chain length and unsaturation play an i mportant role in the interaction of these compounds with model membran es. The results show that long-chain-N-acylethanolamines interact larg ely with DPPC model membranes while a similar effect is not observed f or the short ones.