Urocortin‐expressing olivocochlear neurons exhibit tonotopic and developmental changes in the auditory brainstem and in the innervation of the cochlea

Kaiser, Alexander; Alexandrova, Olga; Grothe, Benedikt

doi:10.1002/cne.22650

Cited by 34 publications

(37 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lateral olivocochlear (LOC) neurons, which are intermingled with principal cells in the LSO in gerbils (Kaiser et al 2011) and mice (Sterenborg et al 2010), have capacitance of only 50% compared with principal neurons (in our experiments, around 10 pF) and display a depolarized resting membrane potential, a delay-type firing pattern, and specific inward and outward current properties (Sterenborg et al 2010). These criteria were used to exclude LOC neurons in the current-clamp mode.…”

Section: Methodsmentioning

confidence: 96%

“…Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice. J Neurophysiol 106: 1443-1453, 2011. First published June 22, 2011 doi:10.1152/jn.01087.2010.-Interaural intensity differences are analyzed in neurons of the lateral superior olive (LSO) by integration of an inhibitory input from the medial nucleus of the trapezoid body (MNTB), activated by sound from the contralateral ear, with an excitatory input from the ipsilateral cochlear nucleus.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice

Walcher

Haßfurth²,

Grothe³

et al. 2011

Journal of Neurophysiology

Self Cite

View full text Add to dashboard Cite

Walcher J, Hassfurth B, Grothe B, Koch U. Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice. J Neurophysiol 106: 1443-1453, 2011. First published June 22, 2011 doi:10.1152/jn.01087.2010.-Interaural intensity differences are analyzed in neurons of the lateral superior olive (LSO) by integration of an inhibitory input from the medial nucleus of the trapezoid body (MNTB), activated by sound from the contralateral ear, with an excitatory input from the ipsilateral cochlear nucleus. The early postnatal refinement of this inhibitory MNTB-LSO projection along the tonotopic axis of the LSO has been extensively studied. However, little is known to what extent physiological changes at these inputs also occur after the onset of sound-evoked activity. Using whole-cell patch-clamp recordings of LSO neurons in acute brain stem slices, we analyzed the developmental changes of inhibitory synaptic currents evoked by MNTB fiber stimulation occurring after hearing onset. We compared these results in gerbils and mice, two species frequently used in auditory research. Our data show that neither the number of presumed input fibers nor the conductance of single fibers significantly changed after hearing onset. Also the amplitude of miniature inhibitory currents remained constant during this developmental period. In contrast, the kinetics of inhibitory synaptic currents greatly accelerated after hearing onset. We conclude that tonotopic refinement of inhibitory projections to the LSO is largely completed before the onset of hearing, whereas acceleration of synaptic kinetics occurs to a large part after hearing onset and might thus be dependent on proper auditory experience. Surprisingly, inhibitory input characteristics, as well as basic membrane properties of LSO neurons, were rather similar in gerbils and mice. auditory brain stem; inhibition; development; glycine receptor; synaptic THE SUPERIOR OLIVE, AN AUDITORY brain stem structure comprising several distinct nuclei, is the first site of binaural interaction in the brain. One of its main nuclei, the lateral superior olive (LSO) receives excitatory inputs from the ipsilateral anteroventral cochlear nucleus and inhibitory inputs from the ipsilateral medial nucleus of the trapezoid body (MNTB) (Tollin 2003). In agreement with these anatomical features, LSO neurons are excited by sounds presented to the ipsilateral ear and are more and more inhibited when the sound intensity increases at the contralateral ear (Boudreau and Tsuchitani 1968;Boudreau and Tsuchitani 1970;Kavanagh and Kelly 1992;Moore and Caspary 1983). This subtraction mechanism enables these neurons to analyze interaural intensity differences, the main cue for the localization of high-frequency sounds.The accurate analysis of interaural intensity differences requires that the excitatory and inhibitory inputs from each ear are mutually adjusted during development. The frequency tuning and the temporal characteristics of the inhibitory and excitatory inputs need to ...

show abstract

Section: Methodsmentioning

confidence: 96%

mentioning

confidence: 99%

Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice

Walcher

Haßfurth²,

Grothe³

et al. 2011

Journal of Neurophysiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…For choline acetyltransferase (ChAT), a polyclonal antibody (AB144P; Millipore) was used that recognizes a single expected band at ∼70 kDa (Western Blot analysis; Kaiser et al 2011). Antibodies directed against MAP2 are shown to detect MAP2a and -b variants at ∼280 kDa and -c variant at 70 kDa in Western blot analysis (data sheet and personal communication from Neuromics).…”

Section: Methodsmentioning

confidence: 99%

Physiology and anatomy of neurons in the medial superior olive of the mouse

Fischl

Burger

Schmidt-Pauly

et al. 2016

Journal of Neurophysiology

Self Cite

View full text Add to dashboard Cite

The medial superior olive (MSO) is an important brain center that computes sound location by comparing small differences in arrival time at the two ears. The MSO is investigated for its specializations for processing with extreme temporal precision. In mice, the MSO is small and difficult to study; thus utilization of genetic methods in MSO studies has been lacking. We present the first comprehensive study of the murine MSO and show that most features are consistent with more heavily investigated species.

show abstract

“…The lateral efferent fibers originate from cells in the lateral superior olive that have been shown to express Ucn1 (Kaiser et al, 2011). Assessment of auditory function in Ucn1 null mice revealed that Ucn1 plays an important role in sound processing.…”

Section: Urocortin Is Expressed In the Cochleamentioning

confidence: 99%

The Cochlear CRF Signaling Systems and their Mechanisms of Action in Modulating Cochlear Sensitivity and Protection Against Trauma

et al. 2011

View full text Add to dashboard Cite

A key requirement for encoding the auditory environment is the ability to dynamically alter cochlear sensitivity. However, merely attaining a steady state of maximal sensitivity is not a viable solution since the sensory cells and ganglion cells of the cochlea are prone to damage following exposure to loud sound. Most often, such damage is via initial metabolic insult that can lead to cellular death. Thus, establishing the highest sensitivity must be balanced with protection against cellular metabolic damage that can lead to loss of hair cells and ganglion cells, resulting in loss of frequency representation. While feedback mechanisms are known to exist in the cochlea that alter sensitivity, they respond only after stimulus encoding, allowing potentially damaging sounds to impact the inner ear at times coincident with increased sensitivity. Thus, questions remain concerning the endogenous signaling systems involved in dynamic modulation of cochlear sensitivity and protection against metabolic stress. Understanding endogenous signaling systems involved in cochlear protection may lead to new strategies and therapies for prevention of cochlear damage and consequent hearing loss. We have recently discovered a novel cochlear signaling system that is molecularly equivalent to the classic hypothalamic-pituitary-adrenal (HPA) axis. This cochlear HPA-equivalent system functions to balance auditory sensitivity and susceptibility to noise-induced hearing loss, and also protects against cellular metabolic insults resulting from exposures to ototoxic drugs. We review the anatomy, physiology, and cellular signaling of this system, and compare it to similar signaling in other organs/tissues of the body.

show abstract

Urocortin‐expressing olivocochlear neurons exhibit tonotopic and developmental changes in the auditory brainstem and in the innervation of the cochlea

Cited by 34 publications

References 61 publications

Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice

Comparative posthearing development of inhibitory inputs to the lateral superior olive in gerbils and mice

Physiology and anatomy of neurons in the medial superior olive of the mouse

The Cochlear CRF Signaling Systems and their Mechanisms of Action in Modulating Cochlear Sensitivity and Protection Against Trauma

Contact Info

Product

Resources

About