Mechanism of pain relief by low-power infrared irradiation: ATP is an IR-target molecule in nociceptive neurons

摘要

Effects of infrared (IR) radiation generated by a low-power CO 2-laser on the membrane of cultured dissociated nociceptive neurons of newborn rat spinal ganglia were investigated using the whole-cell patch-clamp method. Low-power IR radiation diminished the voltage sensitivity of activation gating machinery of slow sodium channels (Na v1.8). Ouabain known to block both transducer and pumping functions of Na +,K +-ATPase eliminated IR irradiation effects. The molecular mechanism of interaction of CO 2-laser radiation with sensory membrane was proposed. The primary event of this interaction is the process of energy absorption by ATP molecules. The transfer of vibrational energy from Na +,K +-ATPase-bound and vibrationally excited ATP molecules to Na +,K +-ATPase activates this enzyme and converts it into a signal transducer. This effect leads to a decrease in the voltage sensitivity of Na v1.8 channels. The effect of IR-radiation was elucidated by the combined application of a very sensitive patch-clamp method and an optical facility with a controlled CO 2-laser. As a result, the mechanism of interaction of non-thermal low-power IR radiation with the nociceptive neuron membrane is suggested.