Voltage activated conductances in motoneurons, and their influence on motor circuits.

CARNEVALE, AGUSTINA; SZCZUPAK, LIDIA

Mar del Plata

Congreso; XXII Congreso anual de la Sociedad Argentina de Investigación en Neurociencias (SAN); 2017

Sociedad Argentina de Investigación en Neurociencias (SAN)

Motoneurons have been conceived as mere output units of networks that control motor behaviors; however, several evidences suggest that they play active roles in shaping motor patterns. In leeches the motoneurons responsible for the elongation of their body, CV (circular ventral) neurons, are linked to the crawling central pattern generator (CPG) via a positive feedback connection.Intrinsic properties of neurons can markedly shape the output of the circuits in which they participate. CV motoneurons exhibit a low threshold spike (LTS) on top of which a burst of action potentials is fired. In the present work, we aim at analyzing the properties of the CV LTS, and develop tools to analyze the role of this phenomenon on crawling.The results suggest that the LTS of CV motoneurons exhibits a threshold close to the resting potential of the neurons, depends on [Ca2+]o, and NNC 55-0396, a blocker of T-type Ca2+ channels, inhibits it.