NMDA-Induced Intrinsic Voltage Oscillations Depend on L-Type Calcium Channels in Spinal Motoneurons of Adult Turtles

Abstract

Guertin, P. A. and J. Hounsgaard. NMDA-induced intrinsic voltage oscillations depend on L-type calcium channels in spinal motoneurons of adult turtles. J. Neurophysiol. 80: 3380–3382, 1998. In a slice preparation from adult turtles, bath-applied N-methyl-d-aspartate (NMDA) induced rhythmic activity in spinal motoneurons. The underlying intrinsic oscillation in membrane potential was revealed in the presence of tetrodotoxin (TTX). NMDA-induced rhythmicity, in the presence or absence of TTX, was abolished or reduced by NMDA receptor antagonists and by three different classes of antagonists for L-type calcium channels. It is suggested that both NMDA receptor channels and L-type calcium channels contribute to NMDA-induced intrinsic oscillations in mature spinal motoneurons.