Limits...
Loss of auditory activity modifies the location of potassium channel KCNQ5 in auditory brainstem neurons.

Caminos E, Garcia-Pino E, Juiz JM - J. Neurosci. Res. (2014)

Bottom Line: The results were comparable after intracochlear TTX injection, which drastically reduced KCNQ5 immunostaining in MNTB calyces and increased immunolabeling in VCN cell bodies.Endbulbs of Held in the VCN also showed diminished KCNQ5 labeling after intracochlear TTX injection.These results show that peripheral activity from auditory nerve afferents is necessary to maintain the subcellular distribution of KCNQ5 in synaptic endings of the auditory brainstem.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Investigación en Discapacidades Neurológicas (IDINE), Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain.

Show MeSH

Related in: MedlinePlus

Effects of bilateral cochlear ablation on KCNQ5 distribution and expression in the AVCN and MNTB. A: Representative drawing with a simplified AVCN–MNTB circuit. B–D: Micrographs of coronal sections of the AVCN from a normal control and a rat after cochlear ablation. Control section shows immunolabeling in the synaptic endings around the cells bodies corresponding to endbulbs of Held (B). KCNQ5 immunoreactivity virtually had disappeared from the endings around AVCN neurons 3 days after cochlear removal (C). AVCN neurons intensely labeled 40 days after ablation (D). E–G: Micrographs illustrating KCNQ5 immunolabeling in the coronal sections of the MNTB in normal control rats and rats after cochlear removal. Representative section of a control animal shows immunolabeling in the synaptic terminals around the principal neurons corresponding to calyces of Held (E). Immunoreactive profiles detected 3 days after cochlea removal (F). KCNQ5 immunoreactive synaptic endings tended to disappear 40 days after ablation (G; arrows). Some cells show immunoreactivity in the endings around cell bodies (arrowheads). Scale bar = 20 µm. [Color figure can be viewed in the online issue, which is available at http://wileyonlinelibrary.com.]
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4359677&req=5

fig02: Effects of bilateral cochlear ablation on KCNQ5 distribution and expression in the AVCN and MNTB. A: Representative drawing with a simplified AVCN–MNTB circuit. B–D: Micrographs of coronal sections of the AVCN from a normal control and a rat after cochlear ablation. Control section shows immunolabeling in the synaptic endings around the cells bodies corresponding to endbulbs of Held (B). KCNQ5 immunoreactivity virtually had disappeared from the endings around AVCN neurons 3 days after cochlear removal (C). AVCN neurons intensely labeled 40 days after ablation (D). E–G: Micrographs illustrating KCNQ5 immunolabeling in the coronal sections of the MNTB in normal control rats and rats after cochlear removal. Representative section of a control animal shows immunolabeling in the synaptic terminals around the principal neurons corresponding to calyces of Held (E). Immunoreactive profiles detected 3 days after cochlea removal (F). KCNQ5 immunoreactive synaptic endings tended to disappear 40 days after ablation (G; arrows). Some cells show immunoreactivity in the endings around cell bodies (arrowheads). Scale bar = 20 µm. [Color figure can be viewed in the online issue, which is available at http://wileyonlinelibrary.com.]

Mentions: Coronal sections at the AVCN and MNTB levels (Fig. 2A) were analyzed. In the AVCN of control animals, there were numerous bouton-like structures corresponding to the synaptic endings labeled for KCNQ5 (Fig. 2B). The AVCN sections from animals in which the cochlea had been removed at P30 displayed a loss of immunoreactive endings around cell bodies starting on day 3 and continuing to day10 after surgery, probably as a result of axonal degeneration. In these animals, a small number of cells showed a few KCNQ5-stained bouton-like structures around their somata (Fig. 2C). On day 40 following cochlear ablation, the KCNQ5-immunostained endings around AVCN neurons had almost completely disappeared, whereas immunoreactive cell bodies, previously not visible, were seen in the AVCN (Fig. 2D).


Loss of auditory activity modifies the location of potassium channel KCNQ5 in auditory brainstem neurons.

Caminos E, Garcia-Pino E, Juiz JM - J. Neurosci. Res. (2014)

Effects of bilateral cochlear ablation on KCNQ5 distribution and expression in the AVCN and MNTB. A: Representative drawing with a simplified AVCN–MNTB circuit. B–D: Micrographs of coronal sections of the AVCN from a normal control and a rat after cochlear ablation. Control section shows immunolabeling in the synaptic endings around the cells bodies corresponding to endbulbs of Held (B). KCNQ5 immunoreactivity virtually had disappeared from the endings around AVCN neurons 3 days after cochlear removal (C). AVCN neurons intensely labeled 40 days after ablation (D). E–G: Micrographs illustrating KCNQ5 immunolabeling in the coronal sections of the MNTB in normal control rats and rats after cochlear removal. Representative section of a control animal shows immunolabeling in the synaptic terminals around the principal neurons corresponding to calyces of Held (E). Immunoreactive profiles detected 3 days after cochlea removal (F). KCNQ5 immunoreactive synaptic endings tended to disappear 40 days after ablation (G; arrows). Some cells show immunoreactivity in the endings around cell bodies (arrowheads). Scale bar = 20 µm. [Color figure can be viewed in the online issue, which is available at http://wileyonlinelibrary.com.]
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4359677&req=5

fig02: Effects of bilateral cochlear ablation on KCNQ5 distribution and expression in the AVCN and MNTB. A: Representative drawing with a simplified AVCN–MNTB circuit. B–D: Micrographs of coronal sections of the AVCN from a normal control and a rat after cochlear ablation. Control section shows immunolabeling in the synaptic endings around the cells bodies corresponding to endbulbs of Held (B). KCNQ5 immunoreactivity virtually had disappeared from the endings around AVCN neurons 3 days after cochlear removal (C). AVCN neurons intensely labeled 40 days after ablation (D). E–G: Micrographs illustrating KCNQ5 immunolabeling in the coronal sections of the MNTB in normal control rats and rats after cochlear removal. Representative section of a control animal shows immunolabeling in the synaptic terminals around the principal neurons corresponding to calyces of Held (E). Immunoreactive profiles detected 3 days after cochlea removal (F). KCNQ5 immunoreactive synaptic endings tended to disappear 40 days after ablation (G; arrows). Some cells show immunoreactivity in the endings around cell bodies (arrowheads). Scale bar = 20 µm. [Color figure can be viewed in the online issue, which is available at http://wileyonlinelibrary.com.]
Mentions: Coronal sections at the AVCN and MNTB levels (Fig. 2A) were analyzed. In the AVCN of control animals, there were numerous bouton-like structures corresponding to the synaptic endings labeled for KCNQ5 (Fig. 2B). The AVCN sections from animals in which the cochlea had been removed at P30 displayed a loss of immunoreactive endings around cell bodies starting on day 3 and continuing to day10 after surgery, probably as a result of axonal degeneration. In these animals, a small number of cells showed a few KCNQ5-stained bouton-like structures around their somata (Fig. 2C). On day 40 following cochlear ablation, the KCNQ5-immunostained endings around AVCN neurons had almost completely disappeared, whereas immunoreactive cell bodies, previously not visible, were seen in the AVCN (Fig. 2D).

Bottom Line: The results were comparable after intracochlear TTX injection, which drastically reduced KCNQ5 immunostaining in MNTB calyces and increased immunolabeling in VCN cell bodies.Endbulbs of Held in the VCN also showed diminished KCNQ5 labeling after intracochlear TTX injection.These results show that peripheral activity from auditory nerve afferents is necessary to maintain the subcellular distribution of KCNQ5 in synaptic endings of the auditory brainstem.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Investigación en Discapacidades Neurológicas (IDINE), Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain.

Show MeSH
Related in: MedlinePlus