The mechanisms and possible sites of acetylcholine release during chick primary sensory neuron differentiation

V Corsetti, C Mozzetta, S Biagioni, GA Tocco, AM Tata - Life sciences, 2012 - Elsevier
V Corsetti, C Mozzetta, S Biagioni, GA Tocco, AM Tata
Life sciences, 2012Elsevier
AIMS: In this study, we evaluated the ability of differentiating embryonic chick DRG neurons
to release and respond to acetylcholine (ACh). In particular, we investigated the neuronal
soma and neurites as sites of ACh release, as well as the mechanism (s) underlying this
release. MAIN METHODS: ACh release from DRG explants in the Campenot chambers was
measured by a chemiluminescent assay. Real-time PCR analysis was used to evaluate the
expression of ChAT, VAChT, mediatophore and muscarinic receptor subtypes in DRGs at …
AIMS
In this study, we evaluated the ability of differentiating embryonic chick DRG neurons to release and respond to acetylcholine (ACh). In particular, we investigated the neuronal soma and neurites as sites of ACh release, as well as the mechanism(s) underlying this release.
MAIN METHODS
ACh release from DRG explants in the Campenot chambers was measured by a chemiluminescent assay. Real-time PCR analysis was used to evaluate the expression of ChAT, VAChT, mediatophore and muscarinic receptor subtypes in DRGs at different developmental stages.
KEY FINDINGS
We found that ACh is released both within the central and lateral compartments of the Campenot chambers, indicating that ACh might be released from both the neuronal soma and fibers. Moreover, we observed that the expression of the ChAT and mediatophore increases during sensory neuron differentiation and during the post-hatching period, whereas VAChT expression decreases throughout development. Lastly, the kinetics of the m2 and m3 transcripts appeared to change differentially compared to the m4 transcript during the same developmental period.
SIGNIFICANCE
The data obtained demonstrate that the DRG sensory neurons are able to release ACh and to respond to ACh stimulation. ACh is released both by the soma and neurite compartments. The contribution of the mediatophore to ACh release appears to be more significant than that of VAChT, suggesting that the non-vesicular release of ACh might represent the preferential mechanism of ACh release in DRG neurons and possibly in non-cholinergic systems.
Elsevier