Collateral sprouting of serotonergic fibers in the cingulate cortex and the septum following cortical-hippocampal lesions.
The parietal cortex and dorsal hippocampus of adult rats were unilaterally ablated. One and 3 months after this operation, changes in serotonergic fiber distribution in the forebrain were studied immunohistochemically. At 1 month, increased numbers of serotonergic fibers were seen in the cingulate cortex and the medial and lateral septal nuclei of the lesioned side. This increase continued to 3 months in the ipsilateral cingulate cortex. In the present study, two different processes of serotonergic fiber collateral sprouting were noted. Plastic changes in serotonergic fibers in the ipsilateral septal nuclei and cingulate cortex may be attributable to the collateral sprouting underlying reactive synaptogenesis and the pruning effect, respectively.
Department of Anatomy, Kyoto Prefectural University of Medicine, Japan.
S
S
Ueda
Y
Y
Sano
M
M
Kawata
D000818:Animals; D006179:Gyrus Cinguli / Q000502:physiology* / Q000648:ultrastructure; D006624:Hippocampus / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D009412:Nerve Fibers / Q000502:physiology*; D009416:Nerve Regeneration; D051381:Rats; D011919:Rats, Inbred Strains; D012688:Septum Pellucidum / Q000502:physiology* / Q000648:ultrastructure; D012701:Serotonin / Q000502:physiology*
D012701:Serotonin