info:eu-repo/semantics/article
Compartmentalization of antagonistic Ca2+ signals in developing cochlear hair cells
Fecha
2018-02Registro en:
Moglie, Marcelo Javier; Fuchs, Paul A.; Elgoyhen, Ana Belen; Goutman, Juan Diego; Compartmentalization of antagonistic Ca2+ signals in developing cochlear hair cells; National Academy of Sciences; Proceedings of the National Academy of Sciences of The United States of America; 115; 9; 2-2018; E2095-E2104
0027-8424
CONICET Digital
CONICET
Autor
Moglie, Marcelo Javier
Fuchs, Paul A.
Elgoyhen, Ana Belen
Goutman, Juan Diego
Resumen
During a critical developmental period, cochlear inner hair cells (IHCs) exhibit sensory-independent activity, featuring action potentials in which Ca2+ ions play a fundamental role in driving both spiking and glutamate release onto synapses with afferent auditory neurons. This spontaneous activity is controlled by a cholinergic input to the IHC, activating a specialized nicotinic receptor with high Ca2+ permeability, and coupled to the activation of hyperpolarizing SK channels. The mechanisms underlying distinct excitatory and inhibitory Ca2+ roles within a small, compact IHC are unknown. Making use of Ca2+ imaging, afferent auditory bouton recordings, and electron microscopy, the present work shows that unusually high intracellular Ca2+ buffering and "subsynaptic" cisterns provide efficient compartmentalization and tight control of cholinergic Ca2+ signals. Thus, synaptic efferent Ca2+ spillover and cross-talk are prevented, and the cholinergic input preserves its inhibitory signature to ensure normal development of the auditory system.