TY  - JOUR
A1  - Chumak, Tetyana
A1  - Rüttiger, Lukas
A1  - Lee, Sze Chim
A1  - Campanelli, Dario
A1  - Zuccotti, Annalisa
A1  - Singer, Wibke
A1  - Popelář, Jiří
A1  - Gutsche, Katja
A1  - Geisler, Hyun-Soon
A1  - Schraven, Sebastian Philipp
A1  - Jaumann, Mirko
A1  - Panford-Walsh, Rama
A1  - Hu, Jing
A1  - Schimmang, Thomas
A1  - Zimmermann, Ulrike
A1  - Syka, Josef
A1  - Knipper, Marlies
T1  - BDNF in Lower Brain Parts Modifies Auditory Fiber Activity to Gain Fidelity but Increases the Risk for Generation of Central Noise After Injury
JF  - Molecular Neurobiology
N2  - For all sensory organs, the establishment of spatial and temporal cortical resolution is assumed to be initiated by the first sensory experience and a BDNF-dependent increase in intracortical inhibition. To address the potential of cortical BDNF for sound processing, we used mice with a conditional deletion of BDNF in which Cre expression was under the control of the Pax2 or TrkC promoter. BDNF deletion profiles between these mice differ in the organ of Corti (BDNF \(^{Pax2}\) -KO) versus the auditory cortex and hippocampus (BDNF \(^{TrkC}\) -KO). We demonstrate that BDNF \(^{Pax2}\) -KO but not BDNF \(^{TrkC}\) -KO mice exhibit reduced sound-evoked suprathreshold ABR waves at the level of the auditory nerve (wave I) and inferior colliculus (IC) (wave IV), indicating that BDNF in lower brain regions but not in the auditory cortex improves sound sensitivity during hearing onset. Extracellular recording of IC neurons of BDNF \(^{Pax2}\) mutant mice revealed that the reduced sensitivity of auditory fibers in these mice went hand in hand with elevated thresholds, reduced dynamic range, prolonged latency, and increased inhibitory strength in IC neurons. Reduced parvalbumin-positive contacts were found in the ascending auditory circuit, including the auditory cortex and hippocampus of BDNF \(^{Pax2}\) -KO, but not of BDNF \(^{TrkC}\) -KO mice. Also, BDNF \(^{Pax2}\) -WT but not BDNF \(^{Pax2}\) -KO mice did lose basal inhibitory strength in IC neurons after acoustic trauma. These findings suggest that BDNF in the lower parts of the auditory system drives auditory fidelity along the entire ascending pathway up to the cortex by increasing inhibitory strength in behaviorally relevant frequency regions. Fidelity and inhibitory strength can be lost following auditory nerve injury leading to diminished sensory outcome and increased central noise.
KW  - Inner hair cell
KW  - Neurotropathic Factor
KW  - Hearing-loss
KW  - Alzheimers-disease
KW  - low-threshold fibers
KW  - cochlear nucleus neurons
KW  - Frequency-response areas
KW  - Inferior colliculus
KW  - Environmental enrichment
KW  - Synaptic plasticity
KW  - Cortical plasticity
KW  - BDNF
KW  - Central hyperactivity
KW  - High-spontaneous rate
KW  - Homeostatic plasticity
KW  - Sound detection threshold
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187341
VL  - 53
IS  - 8
ER  -