Acute sodium-dependent changes in membrane dynamic properties.

Abstract

Na+ ions, which can play a pathogenic role in the development of high blood pressure, have been reported to regulate membrane enzymatic activities, receptor-ligand interaction and coupling of G-protein receptors to their effectors. This study was designed to investigate the in vitro effects of Na+ ions on membrane dynamic properties. The fluorescence anisotropy values of TMA-DPH (trimethylamino-diphenylhexatriene, probe selectively incorporated into the outer leaflet of the plasma membrane) was evaluated in platelets and erythrocytes of sodium-dependent hypertension-prone and -resistant rats of the Sabra Strain. Whereas no difference was observed between the 2 strains, TMA-DPH anisotropy was found to be strongly influenced in platelets by external Na+ ions. In the absence of external Na+, TMA-DPH anisotropy increased in human and rat platelets. In contrast, Na+ ions did not affect the anisotropy when the probe was inserted into erythrocyte ghosts. This indicates that Na+ ions can acutely regulate order parameter and microviscosity of platelet plasma membrane in the regions explored by the probe.

• Authors: K H Le Quan Sang, M Mazeaud, M G Pernollet, D Ben Ishay, M A Devynck
• Journal: Life sciences (Life Sci) Vol. 49 Issue 26 Pg. 1973-7 ( 1991) ISSN: 0024-3205 [Print] Netherlands
• PMID: 1749309 (Publication Type: Journal Article)

Chemical References

• Diphenylhexatriene
• 1-(4-(trimethylamino)phenyl)-6-phenylhexa-1,3,5-triene
• Sodium

Topics

• Animals
• Blood Platelets (metabolism)
• Cell Membrane (metabolism)
• Diphenylhexatriene (analogs & derivatives, metabolism)
• Erythrocyte Membrane (metabolism)
• Fluorescence Polarization
• Male
• Membrane Fluidity (physiology)
• Rats
• Rats, Inbred Strains
• Sodium (metabolism, pharmacology)
• Viscosity