The effect of transcutaneous dynamic electrical neurostimulation on the development of analgesia was studied in behavioral and electrophysiological experiments on rats. A 30-min dynamic electrical stimulation elevated the nociception threshold in tail-flick and hot plate tests, increased the threshold of the late nociceptive flexor reflex, and decreased the number of bursts in the response. Intraperitoneal injection of naloxone (2 mg/kg) abolished the analgesic effect of dynamic electrical neurostimulation. It is concluded that the key role in reflex analgesia during dynamic electrical neurostimulation is played by the endogenous cerebral opioid system, which inhibits the nociceptive signals traveling to CNS via unmyelinated C-fiber afferents.
M L Kukushkin, E E Meizerov, V N Grafova, V S Smirnova, A A Gurov, and V V Chernyshev.
Laboratory of Pain Pathophysiology, Institute of General Pathology and Pathological Physiology, Russian Academy of Medical Sciences, Moscow.
Bull. Exp. Biol. Med. 2003 Mar 1;135(3):228-30.
AbstractThe effect of transcutaneous dynamic electrical neurostimulation on the development of analgesia was studied in behavioral and electrophysiological experiments on rats. A 30-min dynamic electrical stimulation elevated the nociception threshold in tail-flick and hot plate tests, increased the threshold of the late nociceptive flexor reflex, and decreased the number of bursts in the response. Intraperitoneal injection of naloxone (2 mg/kg) abolished the analgesic effect of dynamic electrical neurostimulation. It is concluded that the key role in reflex analgesia during dynamic electrical neurostimulation is played by the endogenous cerebral opioid system, which inhibits the nociceptive signals traveling to CNS via unmyelinated C-fiber afferents.