Full text
| |
| Author(s): |
Luciano Gonçalves
Total Authors: 1
|
| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) |
| Defense date: | 2008-08-18 |
| Examining board members: |
Sara Joyce Shammah Lagnado;
Martin Andreas Metzger;
Claudio Antonio Barbosa de Toledo
|
| Advisor: | Maria Ines Nogueira |
| Abstract | |
The dorsal raphe nucleus (DR) sends massive projections to the forebrain and is implicated in a variety of complex functions. Several studies indicate that neuronal activity in the DR is controlled by the prefrontal cortex (PFC). Since there is no detailed information about the projections from the PFC to the DR, the goal of the present study was to map these projections systematically. The neuronal tracer cholera toxin, subunit b (CTb) was injected at different levels of the DR. By immunohistochemical methods, CTb-ir cells were found highly enriched in the frontal polar cortex and in the medial wall of the PFC. In the lateral PFC, the dorsal lateral insular cortex presented the highest density of CTb-ir neurons. In the orbital PFC, the lateral and dorso-lateral orbital cortex project principally to the central segment of the DR. Injections in the caudal segment of the DR resulted in reduced CTb staining. Our results indicate that the PFC sends massive topographically organized projections to the DR, which may exert a \"top down\" control over neurons in the DR. (AU) | |