Preferential location of prilocaine and etidocaine in phospholipid bilayers: A molecular dynamics study

M. PICKHOLZ; L. F. FRACETO; E. DE PAULA

SYNTHETIC METALS

ELSEVIER SCIENCE SA

Año: 2009 vol. 159 p. 2157 - 2158

0379-6779

In this work, we report a 20-ns constant pressure molecular dynamics simulation of the uncharged form of two amino-amide local anesthetics (LA). etidocaine and prilocaine, present at 1:3 LA:lipid, molar ratio inside the membrane, in the hydrated liquid crystal bilayer phase of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC). Both LAs induced lateral expansion and a concomitant contraction in the bilayer thickness. A decrease in the acyl chain segment order parameter, -S-CD, compared to neat bilayers, was also observed. Besides, both LA molecules got preferentially located in the hydrophobic acyl chains region, with a maximum probability at similar to 12 and similar to 10 angstrom from the center of the bilayer for prilocaine and etidocaine, respectively.