Comparative study on the therapeutic ultrasound effects on erythrocyte membrane-bound and free acetylcholinesterase

Kinetics of erythrocyte acetylcholinesterase activity alterations exposed to ultrasound of therapeutic intensities of 0.88 MHz and 0.05-1.5 W/cm2 was studied. The differences were studied between the mechanisms of the inactivation of membrane-bound and free enzyme: the diminution of active enzyme sites for membrane-bound acetylcholinesterase and the decrease of enzyme-substrate affinity for the free form during sonication. The combined mechanical stresses in the ultrasonic field did not produce inactivation of free enzyme, as compared to the membrane-bound enzyme. Exponential ultrasonic/acoustochemical inactivation curves were obtained for the soluted crystalline form of acetylcholinesterase.