Pharmacology and Neurochemistry of Olivocochlear Efferents
This chapter covers the chemistry and pharmacology of efferent transmission in the cochlea, starting with an overview of the biochemical and biophysical steps following the arrival of an action potential at the peripheral efferent nerve terminal (Sect. 4.1.1). A brief history of advances in understanding the efferent system follows (Sect. 4.1.2). The description of the neurochemistry and pharmacology of efferent action is organized around the sequence of events beginning with the arrival of an action potential at the medial efferent peripheral terminal and ending with the activation of calcium-dependent potassium channels in the outer hair cell (OHC; Sect. 4.2). In Sect. 4.3, other efferent neurotransmitters are covered and, because most of these are associated with the lateral efferent system, it is in this section that much of the knowledge of lateral efferents is presented.
KeywordsHair Cell Tyrosine Hydroxylase Nicotinic Receptor Cholinergic Receptor Efferent Fiber
This work was supported by a grant from the NIDCD (R01 DC000767).
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