The possible participation of a dopaminergic system in mutilating behavior in rats with forelimb deafferentation.
Partial rhizotomy (section of dorsal roots C5 to Th 1 included) leads to abnormal mutilating behavior in the rat, presumably due to pain sensation in the deafferented limb. As dopamine (DA) has been shown to play a role in analgesia, destruction and stimulation of the ventral tegmental area (VTA) were used to check whether they induced an increase or a decrease in the mutilating behavior respectively. Destruction of DA neurons located in the VTA was performed by local administration of 6-hydroxydopamine whereas activation was achieved either by imposed electrical stimulation or by chronic oral administration of D-amphetamine sulfate. These 3 treatments accelerated the onset of the mutilating behavior and induced an extension of the mutilating wounds, D-amphetamine sulfate producing the most pronounced acceleration in their development. The results obtained after destruction of DA-VTA neurons fit well with the working hypothesis. The increase of the mutilating behavior rather than a decrease subsequent to the other treatments could have been caused by the hyperactivity and increase of chewing behavior induced by the less specific stimulating techniques.
D000344:Afferent Pathways / Q000378:metabolism; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D004558:Electric Stimulation; D005552:Forelimb / Q000294:innervation*; D005727:Ganglia, Spinal / Q000378:metabolism; D006801:Humans; D008297:Male; D009619:Nociceptors / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000378:metabolism; D012652:Self Mutilation / Q000378:metabolism*; D013681:Tegmentum Mesencephali / Q000378:metabolism
D011954:Receptors, Dopamine; D004298:Dopamine