Self-consistent field theory of compressible phospholipid membranes at finite pressure

Abstract

In this paper, we use the self-consistent field theory developed in thepreceding paper to study the effects of hydrostatic pressure on theliquid crystal phase of fully hydrated phospholipid membranes, and thecompeting effects of temperature and pressure. In agreement withexperiment, the theory predicts that, at constant temperature, thebilayer thickness and average orientational order parameter both increase withincreasing pressure. When both temperature and pressure are increasedsimultaneously so as to follow the liquid crystal/gel phase coexistencecurve, the thickness and average order parameter decrease, a resultwhich is also in agreement with experiment. We also examine anapproximate relationship between the thickness of the hydrophobicregion and the average orientational order parameter which has beenused to estimate layer thicknesses from NMR data. \\\\ PACS Nos.: 87.22.Bt, 87.10.+e, 64.60.Cn