Ethanol And Dimyristoylphosphatidylethanol Alter Transbilayer Lateral And Rotational Mobility Of Neural Membranes From Brain Membranes

Intramolecular excimerzation of 1,3-di(1-pyrenyl)propane (Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to evaluate effects of ethanol and 1,2-dimyristoylphosphatidylethanol (DMPET) on the rate and range of lateral mobility and the range of the rotational mobility of bulk bilayer structures of neuronal membranes (SPMV) isolated from brain membranes. In a concentration-dependent manner, both ethanol and DMPET increased the rate and range of the lateral mobility and the range of the rotational mobility of bulk bilayer structures of SPMV. Selective quenching of Py-3-Py and DPH by trinitrophenyl groups were utilized to examine the transbilayer asymmetric lateral and rotational mobility of SPMV. Ethanol and DMPET had a greater increasing effect on the lateral and rotational mobility of the outer monolayer as compared to the inner monolayer of SPMV. It has been proven that both ethanol and DMPET exhibit a selective rather than nonselective fluidizing effect within the transbilayer domains of the SPMV. DMPET had a greater potency(about 5,000-times) on aforementioned structural parameters of SPMV than ethanol. The sensitivity of SPMV to ethanol and DMPET was remarkably higher than model membranes of total lipids and phospholipids fraction isolated from SPMV. However, its sensitivity came out to be slightly higher than that of model membranes.