Electronic excitation as a mechanism of the ion selectivity filter

A correlation between the character of pharmacological activity and the ene rgies of electronic transitions in some biologically active molecules, affe cting the nervous system, has been found. In order to explain the correlati on, a new principle of the membrane ion selectivity filter has been suggest ed. The principle is based on the recombination process of a metal cation, passing through the filter, with an electron, when the energy quantum (equa l to the metal ionization energy) is emitted. The amino acid residue group, performing the function of the channel filter, absorbs this quantum, trans its itself into an electronically excited state, changes its conformation a nd lets, as a result, the cation pass. The process is possible only in that case when the amino acid residue group has a transition of the same energy , therefore not all of metals can pass through the filter. From the viewpoi nt of this conception, an active molecule acts because of its transition in to an electronically excited state of the same energy and interfering, ther eby, with the natural processes. (C) 2000 Elsevier Science B.V. All rights reserved.