Kv1 currents mediate a gradient of principal neuron excitability across the tonotopic axis in the rat lateral superior olive

Autor:	Ian D. Forsythe, Fatima Osmani, Margaret Barnes-Davies, Matthew C. Barker
Rok vydání:	2004
Předmět:	Voltage-gated ion channel Chemistry General Neuroscience Depolarization Inhibitory postsynaptic potential Slice preparation medicine.anatomical_structure nervous system medicine Excitatory postsynaptic potential Trapezoid body Neuron Tonotopy Neuroscience
Zdroj:	European Journal of Neuroscience. 19:325-333
ISSN:	0953-816X
DOI:	10.1111/j.0953-816x.2003.03133.x
Popis:	Principal neurons of the lateral superior olive (LSO) detect interaural intensity differences by integration of excitatory projections from ipsilateral bushy cells and inhibitory inputs from the medial nucleus of the trapezoid body. The intrinsic membrane currents active around firing threshold will form an important component of this binaural computation. Whole cell patch recording in an in vitro brain slice preparation was employed to study conductances regulating action potential (AP) firing in principal neurons. Current-clamp recordings from different neurons showed two types of firing pattern on depolarization, one group fired only a single initial AP and had low input resistance while the second group fired multiple APs and had a high input resistance. Under voltage-clamp, single-spiking neurons showed significantly higher levels of a dendrotoxin-sensitive, low threshold potassium current (ILT). Block of ILT by dendrotoxin-I allowed single-spiking cells to fire multiple APs and indicated that this current was mediated by Kv1 channels. Both neuronal types were morphologically similar and possessed similar amounts of the hyperpolarization-activated nonspecific cation conductance (Ih). However, single-spiking cells predominated in the lateral limb of the LSO (receiving low frequency sound inputs) while multiple-firing cells dominated the medial limb. This functional gradient was mirrored by a medio-lateral distribution of Kv1.1 immunolabelling. We conclude that Kv1 channels underlie the gradient of LSO principal neuron firing properties. The properties of single-spiking neurons would render them particularly suited to preserving timing information.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::62c8568041725c8539d2015dfbdc944a https://doi.org/10.1111/j.0953-816x.2003.03133.x Zobrazit plný text záznamu Plný text ve formátu PDF Plný text ve formátu HTML
Nepřihlášeným uživatelům se plný text nezobrazuje	K zobrazení výsledku je třeba se přihlásit.