Effect of low power laser irradiation on nociceptive cells in Hirudo medicinalis

The effect of low power Helium-Neon (He-Ne) and Gallium-Arsenide (Ga-As) laser on the nociceptors in Hirudo medicinalis was studied. The results show that low power laser irradiation does not: affect the membrane potential or the excitability of the nociceptive neurons, affect the mechanical pressure required to activate the nociceptors or their action potentials. The results indicate that the analgesic effects reported in humans with "laser-acupuncture" with similar modes of low power laser are likely not explained by effects on nervous tissue.