Effect of polyunsaturated fatty acid deficiency on dipole relaxation in the membrane interface of rat liver microsomes
Autor: | Carlos P. Sotomayor, Horacio A. Garda, Felipe Aguilar, Marco A. Soto, Rodolfo R. Brenner, Ana M. Bernasconi |
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Rok vydání: | 1997 |
Předmět: |
Male
Essential fatty acid deficiency Lipid Bilayers Biophysics Fluorescence Polarization Biochemistry Biophysical Phenomena chemistry.chemical_compound Membrane Lipids Animals Rats Wistar Lipid bilayer Lipid dynamics Dipole relaxation Fluorescent Dyes Multifrequency fluorometry chemistry.chemical_classification Liposome Fatty Acids Essential Bilayer Rotational diffusion Fatty acid Cell Biology Lateral heterogeneity Rats Lifetime distribution Spectrometry Fluorescence chemistry Energy Transfer Liposomes Microsome Microsomes Liver lipids (amino acids peptides and proteins) Liver microsome Laurdan Polyunsaturated fatty acid |
Zdroj: | Biochimica et biophysica acta. 1323(1) |
ISSN: | 0006-3002 |
Popis: | The influence of a fat-free diet on the lipid dynamics of rat liver microsomes and liposomes of microsomal lipids was studied by using different fluorescence methods. Lifetime distribution and rotational diffusion of probes with different localization in the lipid bilayer were measured using multifrequency fluorometry. Lateral mobility was studied by measuring excimer formation of pyrenedodecanoic acid. Dipolar relaxation in the interfacial region was studied using 2-dimethylamino-6-lauroylnaphthalene (Laurdan). In spite of large changes in the fatty acid composition of microsomal lipids, polyunsaturated fatty acid deficiency showed no effect on the lifetime distribution and rotational mobility of 1,6-diphenyl-1,3,5-hexatriene (DPH), 1-(4-(trimethylamino)phenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), 2-, 7- and 12-(9-anthroiloxy)stearic acids. The treatment did not change the lateral diffusion of pyrenedodecanoic acid, either. However, generalized polarization of Laurdan fluorescence was higher in polyunsaturated fatty acid deficient microsomes as compared to the polyunsaturated fatty acid sufficient ones. This effect was also observed in liposomes of the total microsomal lipids, indicating that the changes in fatty acid composition resulting from polyunsaturated fatty acid deficiency produced a small but significant decrease in the rate of dipolar relaxation in the region of the lipid polar groups of the bilayer. The absence of lipid gel phase domains in rat liver microsomes was also indicated by Laurdan fluorescence features. |
Databáze: | OpenAIRE |
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