Human and rat erythrocyte membranes as a model for studying the effects of organic solvents on membrane-bound acetylcholinesterase in vitro.

The effects of toluene, trichloroethylene and ethanol on membrane acetylcholinesterase (AChE) activity in human and rat intact erythrocytes and erythrocyte ghosts were studied in vitro over a range of concentrations (300-3000 ppm) and at three different incubation temperatures (37, 15 and 5 degrees C). Toluene and trichloroethylene decreased the AChE activity in intact erythrocytes and in erythrocyte ghosts in both species. Trichloroethylene had a more marked effect on erythrocyte ghosts than on intact cells. At low concentrations, toluene generally had greater AChE-inhibiting potency than trichloroethylene. At the concentrations studied, ethanol had no effect on AChE activity. The effects of decreases in incubation temperature on solvent-induced AChE inhibition were very variable. We consider both the human and rat erythrocyte membrane to be a good model for studies of the anaesthetic effects of organic solvents on cell membranes. The effects of organic solvents on AChE, an integral component of the cell membrane, may be one of the critical factors determining the membrane effects of organic solvents even in nerve cells.