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| Author(s): |
Fernando Canova
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2014-03-17 |
| Examining board members: |
Elenice Aparecida de Moraes Ferrari;
César Renato Sartori;
Alexandre César Santos de Rezende;
Suzete Maria Cerutti;
Carlos Amílcar Parada
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| Advisor: | Elenice Aparecida de Moraes Ferrari |
| Abstract | |
The spatial memory has important value for the organism's survival, because it is related with ability to acquire and use space information, enabling the formation of cognitive and spatial maps. The experience with the environment triggers behavioral, cellular and molecular changes in central nervous system that an essential to the formation and consolidation of spatial memory. Therefore, acquisition, consolidation and stability of spatial memory involve plastic changes in the hippocampus of rodents and birds, among these the induction of the expression of early gene transcription such as zenk gene which regulates the expression of numerous other genes and the proteins they control. The gene zenk acts in the formation of new memories and has a role in the regulation of the synapsin protein expression. The expression of synapsins also seems to be related with synaptic mechanisms mediated by the GABAB receptor. This study aimed to evaluate, in pigeons, consolidation and persistence of spatial memory in a situation of food location. The underlying neural plasticity was investigated through the analysis of immunoreactivity for Zenk and Synapsin I proteins in neurons of the hippocampus. Adult, male pigeons (Columba livia) were used in two experiments. Experiment I investigated learning and spatial memory during short (2 sessions) or long duration training (7 sessions). Sessions had 6 experimental trials and were conducted in a arena with 4 feeders. In each trial the bird was released at a different point of the arena, and the time between the release of the bird and the first feeder pecking response (latency of the choice response) was recorded. Testing for spatial strategy was conducted in the arena without any feeder and the time spent in each quadrant was analyzed. Experiment II analyzed the effects of the post-training administration of phaclofen on the consolidation and persistence of spatial memory. Testing of memory persistency occurred 7 days after the 7th training session. Immunohistochemistry of hippocampal tissue was used for the analysis of expression of Zenk and Synapsin I proteins. Number of correct choice increased across training, with values varying between 50 and 88% in the first and 7th session respectively (Anova, p < 0.001). Treatment with GABABantagonist had a facilitatory effect on choice performance which was indicated by lower latency values and higher accuracy values (Anova < 0.001). The values of Zenk positive and Synapsin I positive cells counting were higher in the hippocampus of pigeons that were trained during 7 days and in pigeons treated with phaclofen as compared to their respective controls (Anova p < 0.001). These data indicated that experience with spatial learning of food choice induced expression of Zenk and Synapsin I proteins in the hippocampus of pigeons during the consolidation of spatial memory. Post-training administration of phaclofen suggested a role of GABAB receptor in these experience-dependent synaptic mechanisms. The present results point to the pigeon as interesting animal model for the analysis of neuroplastic mechanisms involved with spatial memory, which are conservative across mammalian and birds species (AU) | |
| FAPESP's process: | 10/01693-1 - Learning of a Food Location Task in Pigeons (Columba livia) and immunoreaction for Zenk protein and synapsin I in the hippocampus: Effects of GABAB receptor antagonist, Phaclofen. |
| Grantee: | Fernando Canova |
| Support Opportunities: | Scholarships in Brazil - Doctorate |