Cholesterol-dependent gramicidin A channel inactivation in red blood cell membranes and lipid bilayer membranes |
| |
Authors: | L V Schagina K Blaskó A E Grinfeldt Y E Korchev A A Lev |
| |
Affiliation: | Institute of Cytology, Academy of Sciences U.S.S.R., Leningrad. |
| |
Abstract: | The exchange diffusions of tracer cations (22Na+, 86Rb+) are studied on gramicidin-A-treated red blood cell (RBC) membranes. A time-dependent decrease in cation permeability has been observed and has been considered to be the result of a channel inactivation process. The channel inactivation appears at 20 and 30 degrees C but not at a temperature as low as 6 degrees C. The gramicidin A channel inactivation can be monitored by a conductivity decay of molecular lipid membranes (BLM) prepared either from cholesterol or from a mixture of cholesterol and phospholipids but not of pure phosphatidylethanolamine. The role of cholesterol in the channel inactivation is discussed. |
| |
Keywords: | |
|