[Comparative testing of analgesia induced by polarized light and analgetics]

In experiments on mice with the tonic pain locus the comparison of analgesia caused by the action of polarized light on an acupuncture point or by two classic analgetics (analginum, tramadol) was performed. The pain was evoked by hypodermic injection of formalin (30 ml of 5% solution) in the plantar region of hindlimb. Intensity of a pain was judged by duration of painful (licking of the pain locus) and non-painful (slipping, eating, running, washing) behavioral reactions for 60 minutes of observation. In animals which received immediately after creation of the tonic pain locus a single intraperitoneal injection of analginum in a doze of 4.2 mg/kg or 8.3 mg/kg the duration of pain response was reduced by 28.5% and 74.9%, respectively. Tramadol decreased the duration of pain behavioral response by 34.2% and 56.2% in a dose 0.8 mg/kg and 8.3 mg/kg, respectively. Statistically significant attenuation of pain (by 50%) was observed in the group of animals exposed to a 10 minute session of polarized light on the antinociceptive acupoint A-36. Compare to animals that received high dozes of analgetics, activity and behavior in mice subjected to an polarized light differed less from the norm. It is possible to suppose, that polarized light will allow a reduction of pharmacological analgetics use and consequently will reduce the risk of development of undesirable side effects in clinic.