Spiral ganglion neurons (SGNs) are the primary auditory neurons in the inner ear, conveying auditory information between sensory hair cells and the central nervous system. Atrial natriuretic peptide (ANP), acting through specific receptors, is a regulatory peptide required for a variety of cardiac and neuronal functions. While the localization of ANP and its receptors (NPR-A and NPR-C) in the i...

PURPOSE Supplementation of exogenous nerve growth factor (NGF) into the cochlea of deafened animals rescues spiral ganglion cells from degeneration. However, a safe and potent delivery of therapeutic proteins, such as NGF, to spiral ganglion cells remains one of the greatest challenges. This study presents the development of self-assembled cubic lipid-based crystalline nanoparticles to enhance ...

Rapamycin is an antifungal agent with immunosuppressive properties. Rapamycin inhibits the mammalian target of rapamycin (mTOR) by blocking the mTOR complex 1 (mTORC1). mTOR is an atypical serine/threonine protein kinase, which controls cell growth, cell proliferation, and cell metabolism. However, less is known about the mTOR pathway in the inner ear. First, we evaluated whether or not the two...

Severe to profound deafness is most often secondary to a loss of or injury to cochlear mechanosensory cells, and there is often an associated loss of the peripheral auditory neural structures, specifically the spiral ganglion neurons and peripheral auditory fibers. Cochlear implantation is currently our best hearing rehabilitation strategy for severe to profound deafness. These implants work by...

The dynamic adjustment of hearing sensitivity and frequency selectivity is mediated by the medial olivocochlear efferent reflex, which suppresses the gain of the 'cochlear amplifier' in each ear. Such efferent feedback is important for promoting discrimination of sounds in background noise, sound localization and protecting the cochleae from acoustic overstimulation. However, the sensory driver...

OBJECTIVES/HYPOTHESIS To evaluate the ability of the Ad28.gfap.atoh1 to promote hair cell regeneration and hearing recovery in cochlea injured with kanamycin and furosemide. STUDY DESIGN In vivo model of hair cell ablation and subsequent treatment with Atoh1. METHODS The hair cells of C57BL/6 mice were ablated with systemic administration of kanamycin and furosemide. The left ears were trea...

BACKGROUND Accurate radiological assessment of the anatomical features of the temporal bone is crucial to prevent damage to vital elements in this area during surgery. Knowing the approximate location of specific temporal bone related landmarks in advance is very important for planning surgery. OBJECTIVES This study compared findings from computed tomography images with those observed directl...

The mammalian inner ear subserves the special senses of hearing and balance. The auditory and vestibular sensory epithelia consist of mechanically sensitive hair cells and associated supporting cells. Hearing loss and balance dysfunction are most frequently caused by compromise of hair cells and/or their innervating neurons. The development of gene- and cell-based therapeutics will benefit from...

Sensorineural hearing loss (SNHL) is a major pathology of the inner ear that affects nearly 600 million people worldwide. Despite intensive researches, this major health problem remains without satisfactory solutions. The pathophysiological mechanisms involved in SNHL include oxidative stress, excitotoxicity, inflammation, and ischemia, resulting in synaptic loss, axonal degeneration, and apopt...

In our experience, tinnitus for otosclerosis may be due to the following: poor vibration of the inner ear fluids, fixation of the footplate, destruction of the Corti hair cells by the proteolytic enzymes, acoustic trauma, or to poor inner ear blood supply due to the hyalinization of the spiral ligament of the stria vascularis. The aim of this article is to suggest some explanations to enhance f...