Network modulation of a slow intrinsic oscillation of cat thalamocortical neurons implicated in sleep delta waves: cortically induced synchronization and brainstem cholinergic suppression

作者：Mircea Steriade, Roberto Curró Dossi, A Nunez · 发表于：Journal of Neuroscience · 年份：1991 · 被引用次数：485 · 研究领域：Neural dynamics and brain function、Photoreceptor and optogenetics research、Sleep and Wakefulness Research

A slow (0.5-4 Hz) oscillation of thalamic neurons was recently described and attributed to the interplay of two intrinsic currents. In this study, we investigated the network modulation of this intrinsic thalamic oscillation within the frequency range of EEG sleep delta-waves. We performed intracellular and extracellular recordings of antidromically identified thalamocortical cells (n = 305) in sensory, motor, associational, and intralaminar nuclei of anesthetized cats. At the resting membrane potential, Vm (-60.3 +/- 0.4 mV, mean +/- SE), cortical stimulation induced spindle-like oscillations (7-14 Hz), whereas at Vm more negative than -65 mV the same stimuli triggered an oscillation within the EEG delta-frequency (0.5-4 Hz), consisting of low-threshold spikes (LTSs) followed by after hyperpolarizing potentials (AHPs). The LTS-AHP sequences outlasted cortical stimuli as a self-sustained rhythmicity at 1-2 Hz. Corticothalamic stimuli were able to transform subthreshold slow (0.5-4 Hz) oscillations, occurring spontaneously at Vm more negative than -65 mV, into rhythmic LTSs crowned by bursts of Na+ spikes that persisted for 10-20 sec after cessation of cortical volleys. Cortical volleys also revived a hyperpolarization-activated slow oscillation when it dampened after a few cycles. Auto- and crosscorrelograms of neuronal pairs revealed that unrelated cells became synchronized after a series of corticothalamic stimuli, with both neurons displaying rhythmic (1-2 Hz) bursts or sp...