INVESTIGADORES
KASANETZ Fernando
artículos
Título:
Turning off cortical ensembles stops striatal Up states and elicits phase perturbations in cortical and striatal slow oscillations in rat in vivo
Autor/es:
FERNANDO KASANETZ; LUIS A. RIQUELME, PATRICIO O'DONNELL AND M. GUSTAVO MURE
Revista:
THE JOURNAL OF PHYSIOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2006 vol. 577 p. 97 - 113
ISSN:
0022-3751
Resumen:
In vivo, cortical neurons and striatal medium spiny neurons
(MSN) display robust subthreshold depolarizations (Up states) during
which they are enabled to fire action potentials. In the cortex, Up
states are believed to occur simultaneously in a neuronal ensemble and
to be sustained by local network interactions. It is known that MSN are
impelled into the Up state by extra-striatal (primarily cortical)
inputs, but the mechanisms that sustain and determine the end of
striatal Up states are still debated. Furthermore, it has not been
established if brisk perturbations of ongoing cortical oscillations
alter rhythmic transitions between Up and Down states in striatal
neurons. Here we report that MSN Up states terminate abruptly when
persistent activity in cortical ensembles providing afferents to a given
striatal region is turned off by local electrical stimulation or ends
spontaneously. In addition, we found that phase perturbations in MSN
membrane potential slow oscillations induced by cortical stimulation
replicate the stimulus-induced dynamics of spiking activity in cortical
ensembles. Overall, these results suggest that striatal Up states are
single-cell subthreshold representations of episodes of persistent
spiking in cortical ensembles. A precise spatial and temporal alignment
between episodes of cortical persistent activity and striatal Up states
would allow MSN to detect specific cortical inputs embedded within a
more general cortical signal.