[Role played in man by myelinated fibers of different diameters for the evocation of a nociceptive flex reflex and the accompanying pain sensation].
Using simultaneous recordings we have made in Man a comparative study of: the sural nerve afferent volley, the nociceptive flexor reflex of a muscle of the lower limb and the associated painful sensation. Two types of stimulations were used, a single short duration electric stimulus, and a train of electric shocks (100/sec). With a single stimulus, the nociceptive flexor reflex and the painful sensation develop only when A delta fibers are recruited. On the other hand, when the stimulations are given by trains the nociceptive flexor reflex and the painful sensation can develop with a stimulus sub-liminar to the threshold of A delta fibers, when A alpha fibers are recruited. When the stimulus activate both A alpha and A delta fibers, the flexion reflex and the pain disappear when a selective blockade of the A delta group is exerted by means of Lidocain.
D000328:Adult; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D009132:Muscles / Q000294:innervation*; D009186:Myelin Sheath / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D012018:Reflex
Détermination chez l'Homme du rôle des fibres myélinisées de différents diamètres dans la mise en jeu d'un réflexe nociceptif de flexion et de la sensation douloureuse qui l'accompagne.