Effect of benzyl alcohol on adenosine triphosphatase, p-nitrophenylphosphatase and acetylcholinesterase in rat erythrocyte membrane.

The irreversible effect of benzyl alcohol on ATPase, p-nitrophenylphosphatase and acetylcholinesterase in the erythrocyte membrane of rats was demonstrated. The ATPase activity in the membranes was stimulated with 10 -70 mM benzyl alcohol and inhibited by concentrations greater than 80 mM. p-Nitrophenylphosphatase was gradually inhibited by concentrations of benzyl alcohol greater than 30 mM. The acetylcholinesterase activity was not affected by concentrations below 100 mM and strongly inhibited by concentrations of benzyl alcohol greater than 150 mM. With the uptake studies of 14C-labeled benzyl alcohol by membranes, the highest uptake was obtained in the presence of 200 mM of benzyl alcohol. And SDS-polyacrylamide gel electrophoresis showed a binding of benzyl alcohol to the major protein bands of the erythrocyte membrane. Therefore, stimulation of the ATPase activity appeared to be the result of an increase in ion uptake due to an increase in the fluidity of the membrane lipid by benzyl alcohol, and the inhibition of the enzymes may be the result of benzyl alcohol-induced denaturation of the membrane components. The difference in the observed inhibition patterns among ATPase, p-nitrophenylphosphatase and acetylcholinesterase may be related to the sensitivity of benzyl alcohol on those enzymes.