The physiological role of GABA in the peripheral nervous system
Final Report Abstract
In this project we explored the role of the inhibitory neurotransmitter Gaba in the physiology of the peripheral nervous system. In particular we wanted to answer how Gaba is accumulating inside peripheral neurons, how it is released and how Gaba influences the channel TrpV1 via its g-protein coupled receptor GabaB1. We found that Gaba is not synthesized via the classic synthesis pathway involving glutamate decarboxylases, nor is the vesicular release machinery for inhibitory neurotransmitters present in PNS neurons. In line with this finding we could show that release of Gaba from peripheral fibers is independent of vesicular release suggesting that Gaba is released via an unknown mechanism. We provide strong evidence that the neurotransmitter Gaba is released through TrpV1, which creates a cell autonomous feedback mechanism to control TrpV1 sensitization via GabaB1. How GabaB1 functionally and molecularly interacts with TrpV1 remains to be shown and will be the subject of future research.
