In vitro ictogenesis and parahippocampal networks in a rodent model of temporal lobe epilepsy.
Temporal lobe epilepsy (TLE) is a chronic epileptic disorder involving the hippocampal formation. Details on the interactions between the hippocampus proper and parahippocampal networks during ictogenesis remain, however, unclear. In addition, recent findings have shown that epileptic limbic networks maintained in vitro are paradoxically less responsive than non-epileptic control (NEC) tissue to application of the convulsant drug 4-aminopyridine (4AP). Field potential recordings allowed us to establish here the effects of 4AP in brain slices obtained from NEC and pilocarpine-treated epileptic rats; these slices included the hippocampus and parahippocampal areas such as entorhinal and perirhinal cortices and the amygdala. First, we found that both types of tissue generate epileptiform discharges with similar electrographic characteristics. Further investigation showed that generation of robust ictal-like discharges in the epileptic rat tissue is (i) favored by decreased hippocampal output (ii) reinforced by EC-subiculum interactions and (iii) predominantly driven by amygdala networks. We propose that a functional switch to alternative synaptic routes may promote network hyperexcitability in the epileptic limbic system.
Panuccio
G
G
Montreal Neurological Institute and Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
D'Antuono
M
M
de Guzman
P
P
De Lannoy
L
L
Biagini
G
G
Avoli
M
M
D015761:4-Aminopyridine / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000679:Amygdala / Q000187:drug effects / Q000503:physiopathology*; D000818:Animals; D004195:Disease Models, Animal; D004594:Electrophysiology; D004833:Epilepsy, Temporal Lobe / Q000139:chemically induced / Q000503:physiopathology*; D006624:Hippocampus / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D009415:Nerve Net / Q000187:drug effects / Q000503:physiopathology*; D020534:Parahippocampal Gyrus / Q000187:drug effects / Q000503:physiopathology*; D010862:Pilocarpine; D051381:Rats; D017207:Rats, Sprague-Dawley
D010862:Pilocarpine; D015761:4-Aminopyridine
Science. 2003 Jul 25;301(5632):463; author reply 463
12881553
Brain Res Bull. 2006 Dec 11;71(1-3):127-38
17113938
Hippocampus. 2006;16(10):843-60
16897722
Neuroscience. 2004;126(2):485-501
15207366
J Neurosci. 2006 Nov 15;26(46):11850-6
17108158
Prog Neurobiol. 1989;33(3):161-253
2682783
Electroencephalogr Clin Neurophysiol. 1972 Mar;32(3):281-94
4110397
J Neurosci. 1996 Jun 15;16(12):3912-24
8656285
J Neurophysiol. 2000 Mar;83(3):1115-24
10712442
Ann N Y Acad Sci. 2000 Jun;911:369-91
10911886
J Neurophysiol. 2001 Dec;86(6):2887-95
11731545
Ann Neurol. 1989 Sep;26(3):321-30
2508534
Epilepsia. 2000;41 Suppl 6:S90-5
10999527
Neurosci Lett. 1994 Jun 20;174(2):160-4
7970173
J Neurosci. 1997 Dec 1;17(23):9308-14
9364076
Epilepsy Res. 1998 Sep;32(1-2):233-53
9761324
Adv Neurol. 1999;79:743-61
10514861
Epilepsy Res. 1997 Jan;26(2):315-27
9095393
J Neurophysiol. 2006 Apr;95(4):2143-54
16381802
Neurosci Lett. 1995 Dec 1;201(1):87-91
8830321
Ann Neurol. 1998 Dec;44(6):923-34
9851437
Epilepsia. 1991 Nov-Dec;32(6):778-82
1743148
Science. 1987 Jan 2;235(4784):73-6
2879352
J Physiol. 2003 May 15;549(Pt 1):219-30
12665605
J Neurophysiol. 2002 Jan;87(1):634-9
11784779
J Comp Neurol. 1999 Jun 14;408(4):449-60
10340497
N Engl J Med. 2001 Aug 2;345(5):311-8
11484687
Neuroscience. 2004;123(4):875-86
14751281
J Neurosci Methods. 2008 Jul 30;172(2):143-57
18550176
J Neurosci. 2003 Sep 17;23(24):8471-9
13679415
J Neurosci. 1988 Jul;8(7):2213-26
3249220
Science. 2004 Jul 23;305(5683):532-5
15273397
Exp Brain Res. 1991;87(3):581-96
1783028
Eur J Neurosci. 2001 Apr;13(7):1371-9
11298797
J Comp Neurol. 2005 Mar 21;483(4):476-88
15700275
Science. 2002 Nov 15;298(5597):1418-21
12434059
Neuroscience. 2009 Sep 29;163(1):415-29
19540312
Neurobiol Dis. 2008 Feb;29(2):186-200
17942314
Eur J Neurosci. 1998 Mar;10(3):1011-8
9753168
J Comp Neurol. 2000 Oct 23;426(3):441-67
10992249
Eur J Neurosci. 2001 Feb;13(4):657-69
11207801
Eur J Neurosci. 1996 Dec;8(12):2711-25
8996821
Prog Neurobiol. 2002 Oct;68(3):167-207
12450487
J Neurosci. 2006 Jan 11;26(2):406-10
16407536
Epilepsia. 2005;46 Suppl 5:17-21
15987248
Nat Med. 1998 Oct;4(10):1166-72
9771750
Eur J Neurosci. 2003 Nov;18(10):2779-91
14656327
Brain. 2008 Jun;131(Pt 6):1516-27
18504292
J Physiol. 2005 Aug 1;566(Pt 3):885-900
15932889
Neurobiol Dis. 2005 Aug;19(3):451-60
16023587
Epilepsia. 2009 Jan;50 Suppl 1:53-8
19125849
Brain Res. 2000 Mar 17;859(1):15-20
10720610
Exp Neurol. 2004 Jun;187(2):367-79
15144863
Neurosci Res. 2002 Sep;44(1):91-100
12204297
J Neurophysiol. 1991 Sep;66(3):999-1009
1684384
Epilepsy Res. 1993 Dec;16(3):223-33
8119273
J Neurosci. 2006 Apr 26;26(17):4613-23
16641241
Neuromolecular Med. 2005;7(4):325-42
16391389
Epilepsia. 2002 Apr;43(4):350-7
11952764
J Neurosci. 2007 Sep 12;27(37):9866-73
17855601
J Physiol. 2008 Apr 1;586(7):1867-83
18238812
Neuroscience. 2003;120(1):75-84
12849742
Epilepsy Res. 2008 Feb;78(2-3):102-16
18226499
Trends Neurosci. 2005 Jun;28(6):334-40
15927690
Brain Res. 1976 Dec 24;118(3):475-8
1009431
J Neuropathol Exp Neurol. 2008 Jul;67(7):687-701
18596544