Rhythmic bursting in the cortico-subthalamo-pallidal network during spontaneous genetically determined spike and wave discharges.
Absence seizures are characterized by impairment of consciousness associated with bilaterally synchronous spike-and-wave discharges (SWDs) in the electroencephalogram (EEG), which reflect paroxysmal oscillations in thalamocortical networks. Although recent studies suggest that the subthalamic nucleus (STN) provides an endogenous control system that influences the occurrence of absence seizures, the mechanisms of propagation of cortical epileptic discharges in the STN have never been explored. The present study provides the first description of the electrophysiological activity in the cortico-subthalamo-pallidal network during absence seizures in the genetic absence epilepsy rats from Strasbourg, a well established model of absence epilepsy. In corticosubthalamic neurons, the SWDs were associated with repetitive suprathreshold depolarizations correlated with EEG spikes. These cortical paroxysms were reflected in the STN by synchronized, rhythmic, high-frequency bursts of action potentials. Intracellular recordings revealed that the intraburst pattern in STN neurons was sculpted by an early depolarizing synaptic potential, followed by a short hyperpolarization and a rebound of excitation. The rhythmic hyperpolarizations in STN neurons during SWDs likely originate from a subpopulation of pallidal neurons exhibiting rhythmic bursting temporally correlated with the EEG spikes. The repetitive discharges in STN neurons accompanying absence seizures might convey powerful excitation to basal ganglia output nuclei and, consequently, may participate in the control of thalamocortical SWDs.
Paz
Jeanne Tamar
JT
Institut National de la Santé et de la Recherche Médicale U114, Chaire de Neuropharmacologie, Collège de France and U667, 75231 Paris Cedex 05, France. jeanne.paz@college-de-france.fr
Deniau
Jean-Michel
JM
Charpier
Stéphane
S
D000200:Action Potentials; D000818:Animals; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D004832:Epilepsy, Absence / Q000235:genetics / Q000503:physiopathology*; D045604:Extracellular Fluid; D005145:Face / Q000294:innervation; D005917:Globus Pallidus / Q000503:physiopathology*; D007091:Image Processing, Computer-Assisted; D007424:Intracellular Fluid; D009044:Motor Cortex / Q000503:physiopathology; D009055:Mouth / Q000294:innervation; D009474:Neurons / Q000502:physiology; D051381:Rats; D011922:Rats, Mutant Strains; D020531:Subthalamic Nucleus / Q000503:physiopathology*
J Neurosci. 2004 Jul 28;24(30):6816-25
15282287
J Neurophysiol. 2002 Mar;87(3):1348-62
11877509
J Neurophysiol. 2000 Apr;83(4):1951-7
10758106
Epilepsy Res. 1998 Sep;32(1-2):213-23
9761322
Neuroscience. 1987 May;21(2):429-40
2886955
J Neurophysiol. 2000 Jul;84(1):289-300
10899204
J Neurosci. 2002 Mar 15;22(6):2323-34
11896171
Trends Neurosci. 2002 Oct;25(10):525-31
12220881
J Neurosci. 2003 Aug 20;23(20):7525-42
12930791
Annu Rev Neurosci. 2001;24:653-75
11520915
Brain Res. 1991 Nov 15;564(2):296-305
1810628
Epileptic Disord. 2002 Dec;4 Suppl 3:S61-72
12495876
J Neurosci Methods. 1996 Apr;65(2):113-36
8740589
Brain Res. 1988 May 10;448(1):20-9
2839269
Brain Res. 1981 Jun 15;214(2):411-5
7237177
Neuropharmacology. 1999 Nov;38(11):1699-706
10587086
Brain Res. 1986 Mar;396(1):77-96
3708387
Neuroscience. 1996 Apr;71(3):721-8
8867044
Epilepsia. 2003 Dec;44(12):1513-20
14636321
J Neurophysiol. 2000 May;83(5):3169-72
10805713
J Neurosci. 2000 Jan 15;20(2):820-33
10632612
J Physiol. 1998 Jun 1;509 ( Pt 2):449-56
9575294
J Neurosci. 2003 Jun 15;23(12):5247-57
12832549
J Neurophysiol. 2000 Nov;84(5):2630-7
11068004
J Neurophysiol. 1989 Feb;61(2):311-30
2918357
Brain Res. 1994 Feb 14;636(2):308-19
8012814
Brain Res. 1989 Sep 25;498(1):64-72
2551457
Epileptic Disord. 2002 Dec;4 Suppl 3:S9-22
12495871
J Physiol. 1996 Jul 1;494 ( Pt 1):251-64
8814619
J Neurosci Methods. 1980 Dec;3(2):129-49
6110810
J Neurosci. 1998 Nov 15;18(22):9539-46
9801390
Prog Neurobiol. 1998 May;55(1):27-57
9602499
Nat Rev Neurosci. 2002 May;3(5):371-82
11988776
Neuroscience. 2004;123(2):299-336
14698741
Trends Neurosci. 1990 Mar;13(3):99-104
1691879
J Neurosci. 1999 Jan 15;19(2):599-609
9880580
J Comp Neurol. 1980 Aug 15;192(4):751-68
7419753
Nature. 1999 Aug 12;400(6745):677-82
10458164
J Neurosci. 2003 Oct 22;23(29):9565-74
14573536
Brain Res. 1985 May 20;334(2):227-33
3995318
J Physiol. 2003 Aug 1;550(Pt 3):947-59
12844508
Neuroscience. 2001;105(1):203-11
11483312
J Neurosci. 2003 Oct 29;23(30):9929-36
14586023
Brain Res. 1979 Nov 2;176(2):273-84
40667
Neurosci Lett. 1978 Sep;9(2-3):117-21
19605204
Biophys J. 1969 Dec;9(12):1483-508
5352228
J Comp Neurol. 1985 Jun 1;236(1):14-28
2414329
Nat Rev Neurosci. 2002 May;3(5):362-70
11988775
J Neurosci. 2002 Oct 1;22(19):8762-70
12351752
Brain. 1953 Mar;76(1):50-69
13041922
Nat Rev Neurosci. 2004 Feb;5(2):121-34
14735115
J Neurosci. 1999 Sep 1;19(17):7617-28
10460267
Epilepsy Res. 1998 Jun;31(1):39-46
9696299
J Neurosci. 2001 Sep 1;21(17):6874-88
11517275
J Physiol. 2003 Nov 1;552(Pt 3):881-905
12923213
J Neurosci. 2001 Aug 1;21(15):5764-72
11466448
Neuroscience. 2001;106(2):313-30
11566503
J Neural Transm Suppl. 1992;35:37-69
1512594