Field-induced electroconformational damages in cell membrane proteins: a new mechanism involved in electrical injury

Abstract

Mechanisms of electrical injury may involve electrical and thermal phenomena. These factors affect cell membranes and membrane proteins. Results of the stress of these factors include permeabilization of the cell membranes and dysfunctions of the membrane proteins, especially the voltage-sensitive membrane proteins. In this paper, we discussed mechanisms involved in damaging the K⁺ channel proteins. We show that the level of channel damage is not directly correlated to the shock field-induced huge channel currents, therefore not to the thermal damages in the proteins. Instead, the channel damages are dependent on the field-induced supramembrane potential (magnitude and polarity). Moreover, the number of limiting charge particles which function as the voltage-sensor in the channel gating system was reduced after a supramembrane potential shock. These results indicate that a supramembrane potential shock may cause electroconformational changes in the membrane proteins, which may reveal a new mechanism involved in electrical injury. Moreover, these studies also provide evidence that external electric fields can be used to modify functions of the voltage-sensitive membrane proteins by electrical coupled conformational changes in the proteins.