Abstract
Transplantation of fetal serotonergic neurons into the hypothalamus restored muricide (mouse killing behavior) in the rat with raphe lesion induced by 5, 7-dihydroxytryptamine (selective serotonergic neurotoxine). Immunohistochemical and neurochemical studies indicated that recovery of serotonergic innervation in the lateral hypothalamic area by the graft brought about the inhibition of muricide. The grafted serotonergic neurons are strongly related to the inhibitory action on the muricide. Transplanted serotonergic neuron system can result in a reinnervation of the host, and leads to a reestablishment of the aggressive behavior.