Muscarinic modulation of the Xenopus laevis tadpole spinal mechanosensory pathway
Abstract
Muscarinic acetylcholine receptors (mAChRs) mediate effects of acetylcholine (ACh) in many systems, including those involved in spinal functions like locomotion. In Xenopus laevis tadpoles at two days old, a model vertebrate for motor control research, we investigated the role of mAChRs in the skin mechanosensory pathway. We found that mAChR activation by carbachol did not affect the sensory Rohon-Beard neuron properties. However, carbachol could hyperpolarise sensory interneurons and decrease their voltage responses to outward currents. Carbachol could increase the threshold for the mechanosensory pathway to start swimming, preventing the initiation of swimming at higher concentrations altogether. Recording from the sensory interneurons in carbachol showed that their spiking after skin stimulation was depressed. However, the general muscarinic antagonist atropine did not have a clear effect on the swimming threshold or the modulation of sensory interneuron membrane conductance. Our results suggest the skin mechanosensory pathway may be subject to muscarinic modulation in this simple vertebrate system.
Citation
Porter , N J & Li , W-C 2018 , ' Muscarinic modulation of the Xenopus laevis tadpole spinal mechanosensory pathway ' , Brain Research Bulletin , vol. 139 , pp. 278-284 . https://doi.org/10.1016/j.brainresbull.2018.03.015
Publication
Brain Research Bulletin
Status
Peer reviewed
ISSN
0361-9230Type
Journal article
Rights
© 2018 Elsevier Ltd. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1016/j.brainresbull.2018.03.015
Description
This research was supported by a BBSRC studentship to N.J.P. and partially by a BBSRC grant to W.-C. L. (BB/L00111X/1).Collections
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