Dendrite-derived supernumerary axons on adult axotomized motor neurons possess proteins that are essential for the initiation and propagation of action potentials and synaptic vesicle release

TY - JOUR

T1 - Dendrite-derived supernumerary axons on adult axotomized motor neurons possess proteins that are essential for the initiation and propagation of action potentials and synaptic vesicle release

AU - Meehan, Claire Francesca

AU - MacDermid, Victoria E

AU - Montague, Steven J

AU - Neuber-Hess, Monica

AU - Rose, P Ken

PY - 2011/5/4

Y1 - 2011/5/4

N2 - Axotomy can trigger profound alterations in the neuronal polarity of adult neurons in vivo. This can manifest itself in the development of new axon-like processes emanating from the tips of distal dendrites. Previously, these processes have been defined as axonal based on their axonal morphology. This study extends this definition to determine whether, more importantly, these processes possess the prerequisite molecular machinery to function as axons. Using a combination of intracellular labeling and immunohistochemistry, we demonstrate that the distribution of voltage-gated sodium channels on these processes matches the arrangement of these channels that is necessary for the initiation and conduction of action potentials. At terminal bouton-like structures they possess key proteins necessary for the release of synaptic vesicles (SV2 and synaptophysin). Thus, axon-like processes emanating from the tips of distal dendrites represent a rearrangement of neuronal polarity whereby axotomized neurons can develop additional functional axons in vivo.

AB - Axotomy can trigger profound alterations in the neuronal polarity of adult neurons in vivo. This can manifest itself in the development of new axon-like processes emanating from the tips of distal dendrites. Previously, these processes have been defined as axonal based on their axonal morphology. This study extends this definition to determine whether, more importantly, these processes possess the prerequisite molecular machinery to function as axons. Using a combination of intracellular labeling and immunohistochemistry, we demonstrate that the distribution of voltage-gated sodium channels on these processes matches the arrangement of these channels that is necessary for the initiation and conduction of action potentials. At terminal bouton-like structures they possess key proteins necessary for the release of synaptic vesicles (SV2 and synaptophysin). Thus, axon-like processes emanating from the tips of distal dendrites represent a rearrangement of neuronal polarity whereby axotomized neurons can develop additional functional axons in vivo.

KW - Action Potentials

KW - Animals

KW - Axons

KW - Axotomy

KW - Cats

KW - Dendrites

KW - Immunohistochemistry

KW - Motor Neurons

KW - Sodium Channels

KW - Synapses

KW - Synaptic Transmission

KW - Synaptic Vesicles

KW - Synaptophysin

U2 - 10.1523/JNEUROSCI.5377-10.2011

DO - 10.1523/JNEUROSCI.5377-10.2011

M3 - Journal article

C2 - 21543602

SN - 0270-6474

VL - 31

SP - 6732

EP - 6740

JO - Journal of Neuroscience

JF - Journal of Neuroscience

IS - 18

ER -