[Hypoalgesia in partially de-afferented rats].
When placed on a hot plate, rats with 5 consecutive dorsal root sections, present long licking-latencies of the posterior limbs, sign of a generalised hypoalgesia. To determine if this hypoalgesia is the result of the deafferentation or of the extent of the anterior limb automutilation performed by such deafferented rats, the licking-latency was measured in two groups of deafferented rats. In one of these groups all the rats performed automutilation, in the other a daily injection of amoxicillin resulted in an important reduction of the autotomic behavior. In both groups the licking-latency was twice its value in non-deafferented animals (order of 14 s in place of 7 s). Thus, hypoalgesia is the consequence of the deafferentation and not of the connected automutilation extent. To explain these results it is proposed that this hypoalgesia results from the algic sensitivity decrease observed in a normally afferented area when a painful sensation is felt in an other territory, the deafferented area in this case.
Unité de neuropsychopharmacologie expérimentale CNRS URA 1170, Saint-Etienne du Rouvray.
C
C
Suaudeau
D000344:Afferent Pathways / Q000601:surgery*; D000658:Amoxicillin / Q000494:pharmacology; D000818:Animals; D006358:Hot Temperature / Q000009:adverse effects; D008297:Male; D010147:Pain Measurement; D051381:Rats; D017207:Rats, Sprague-Dawley
D000658:Amoxicillin
Hypoalgie chez les rats partiellement désafférentés.