Slow (<1 Hz) periodic activity is a distinctive discharge pattern observed in different cortical and sub-cortical structures during sleep and anesthesia. By performing field and cellular recordings, we demonstrated that slow periodic events (0.02-0.4 Hz) are spontaneously generated in the entorhinal cortex of the in vitro isolated whole brain of the guinea pig. These events were characterized by gradually developing runs of low-amplitude (50-300 μV), high-frequency (25-70 Hz) oscillations superimposed on a slow potential that lasted 1-3 s. Both slow and fast components showed a phase reversal in the superficial layers. In layer II-III entorhinal neurons, the slow periodic events correlated to a slowly developing depolarizing envelope capped by subthreshold membrane potential oscillations and action potential discharge. Slow periodic field events propagated tangentially across the entorhinal cortex and could be triggered by stimulation of superficial associative fibers, suggesting that they were generated by and propagated via network interactions in the superficial layers. Slow periodic events were reversibly abolished by muscarinic excitation elicited by carbachol (50 μM) that promoted intracellular membrane potential depolarization associated with continuous fast oscillatory activity in the gamma frequency range. These results suggest that, as proposed in vivo, activity changes in the entorhinal cortex of the in vitro isolated guinea-pig brain reflect different activation states that are under cholinergic control.
Slow periodic events and their transition to gamma oscillations in the entorhinal cortex of the isolated Guinea pig brain / DICKSON CT; G. BIELLA; DE CURTIS M.. - In: JOURNAL OF NEUROPHYSIOLOGY. - ISSN 0022-3077. - 90(2003), pp. 39-46.
Scheda prodotto non validato
Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo
Titolo: | Slow periodic events and their transition to gamma oscillations in the entorhinal cortex of the isolated Guinea pig brain |
Autori: | |
Data di pubblicazione: | 2003 |
Rivista: | |
Citazione: | Slow periodic events and their transition to gamma oscillations in the entorhinal cortex of the isolated Guinea pig brain / DICKSON CT; G. BIELLA; DE CURTIS M.. - In: JOURNAL OF NEUROPHYSIOLOGY. - ISSN 0022-3077. - 90(2003), pp. 39-46. |
Abstract: | Slow (<1 Hz) periodic activity is a distinctive discharge pattern observed in different cortical and sub-cortical structures during sleep and anesthesia. By performing field and cellular recordings, we demonstrated that slow periodic events (0.02-0.4 Hz) are spontaneously generated in the entorhinal cortex of the in vitro isolated whole brain of the guinea pig. These events were characterized by gradually developing runs of low-amplitude (50-300 μV), high-frequency (25-70 Hz) oscillations superimposed on a slow potential that lasted 1-3 s. Both slow and fast components showed a phase reversal in the superficial layers. In layer II-III entorhinal neurons, the slow periodic events correlated to a slowly developing depolarizing envelope capped by subthreshold membrane potential oscillations and action potential discharge. Slow periodic field events propagated tangentially across the entorhinal cortex and could be triggered by stimulation of superficial associative fibers, suggesting that they were generated by and propagated via network interactions in the superficial layers. Slow periodic events were reversibly abolished by muscarinic excitation elicited by carbachol (50 μM) that promoted intracellular membrane potential depolarization associated with continuous fast oscillatory activity in the gamma frequency range. These results suggest that, as proposed in vivo, activity changes in the entorhinal cortex of the in vitro isolated guinea-pig brain reflect different activation states that are under cholinergic control. |
Handle: | http://hdl.handle.net/11571/100400 |
Appare nelle tipologie: | 1.1 Articolo in rivista |