Recurrent Excitation Between Motoneurones Propagates Across Segments and is Purely Glutamatergic

Overview

Journal PLoS Biol

Specialty Biology

Date 2018 Mar 15

PMID 29538375

Citations 41

Authors

Gardave S Bhumbra

Marco Beato

Affiliations

Soon will be listed here.

Abstract

Spinal motoneurones (Mns) constitute the final output for the execution of motor tasks. In addition to innervating muscles, Mns project excitatory collateral connections to Renshaw cells (RCs) and other Mns, but the latter have received little attention. We show that Mns receive strong synaptic input from other Mns throughout development and into maturity, with fast-type Mns systematically receiving greater recurrent excitation than slow-type Mns. Optical recordings show that activation of Mns in one spinal segment can propagate to adjacent segments even in the presence of intact recurrent inhibition. While it is known that transmission at the neuromuscular junction is purely cholinergic and RCs are excited through both acetylcholine and glutamate receptors, here we show that neurotransmission between Mns is purely glutamatergic, indicating that synaptic transmission systems are differentiated at different postsynaptic targets of Mns.

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