Full text
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| Author(s): |
Jessica dos Santos
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Carlos. |
| Institution: | Universidade de São Paulo (USP). Instituto de Física de São Carlos (IFSC/BT) |
| Defense date: | 2013-07-15 |
| Examining board members: |
Reynaldo Daniel Pinto;
Rafael Victório Carvalho Guido;
Marcelo Bussotti Reyes
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| Advisor: | Reynaldo Daniel Pinto |
| Abstract | |
Studying the effect of neurotransmitters and neuromodulators usually consists in observing the behavior of a system, or part of it, when exposed to stationary concentrations of the drugs that completely lack any time dependency. Here we describe a protocol that we developed to study the changes of the emerging rhythmic pattern of a Central Pattern Generator (CPG) due to the effects of the aplications dynamics of tiny puffs of glutamate (Glu, 1mM) or serotonin (5-HT, 10 mM) to the neurons and their neuropil. We experimented on the stomatogastric nervous system of Callinectes sapidus and Callinectes danae (pyloric CPG) during normal operation in vitro, that was characterized using bursting frequency, neurons number of spikes/burst, their duty cycle, etc. From the extracelular activity of one of the CPG neurons, a dynamic clamp based protocol (real time interaction between living nervous tissue and computer simulation) detected in real time a given pattern of activity present in a burst and triggered a picospritzer to puff a small amount of solution with the drug in the neighborhood of the neurons and synapses of the CPG, from where it was washed through constant perfusion of normal saline. Such arrangement allowed us to address what are the differences on the emerging CPG behavior when the stimuli was activity synchronous or asynchronous, but with the same mean amount of drug delivered in both cases. In general, our results showed that the same stimulus presented in different ways to the same nervous circuit may generate different responses even in a cell level. Finally, the protocol proved to be more efficient when the drug activity time scale is smaller than the time scale of the CPG bursting behavior. In the future we should work with other neuromodulators and neurotransmiters to improve the protocol. (AU) | |
| FAPESP's process: | 10/04638-1 - Real-time pattern dependent drug application protocols applied to central pattern generators: effects of serotonin (5-HT) and glutamate in the stomatogastric nervous system of Callinectes sapidus. |
| Grantee: | Jessica dos Santos |
| Support Opportunities: | Scholarships in Brazil - Master |