title: Dorsoventral differences in Kv7/M-current and its impact on resonance, temporal summation and excitability in rat hippocampal pyramidal cells.
abstract: In rodent hippocampi, the connections, gene expression and functions differ along the dorsoventral (D-V) axis. CA1 pyramidal cells show increasing excitability along the D-V axis, although the underlying mechanism is not known. In the present study, we investigated how the M-current (IM ), caused by Kv7/M (KCNQ) potassium channels, and known to often control neuronal excitability, contributes to D-V differences in intrinsic properties of CA1 pyramidal cells. Using whole-cell patch clamp recordings and the selective Kv7/M blocker 10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone dihydrochloride (XE991) in hippocampal slices from 3- to 4-week-old rats, we found that: (i) IM had a stronger impact on subthreshold electrical properties in dorsal than ventral CA1 pyramidal cells, including input resistance, temporal summation of artificial synaptic potentials, and M-resonance; (ii) IM activated at more negative potentials (left-shifted) and had larger peak amplitude in the dorsal than ventral CA1; and (iii) the initial spike threshold (during ramp depolarizations) was elevated, and the medium after-hyperpolarization and spike frequency adaptation were increased (i.e. excitability was lower) in the dorsal rather than ventral CA1. These differences were abolished or reduced by application of XE991, indicating that they were caused by IM . Thus, it appears that IM has stronger effects in dorsal than in ventral rat CA1 pyramidal cells because of a larger maximal M-conductance and left-shifted activation curve in the dorsal cells. These mechanisms may contribute to D-V differences in the rate and phase coding of position by CA1 place cells, and may also enhance epileptiform activity in ventral CA1.
authors: Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
authors: Christoph
authors: C
authors: Hönigsperger
authors: Máté
authors: M
authors: Marosi
authors: Ricardo
authors: R
authors: Murphy
authors: Johan F
authors: JF
authors: Storm
mesh_terms: D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D056547:CA1 Region, Hippocampal / Q000166:cytology / Q000502:physiology; D066298:In Vitro Techniques; D051656:KCNQ Potassium Channels / Q000037:antagonists & inhibitors / Q000502:physiology*; D008297:Male; D026902:Potassium Channel Blockers / Q000494:pharmacology; D017966:Pyramidal Cells / Q000502:physiology*; D017208:Rats, Wistar
chemical_list: C112297:10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone; D000873:Anthracenes; D051656:KCNQ Potassium Channels; D026902:Potassium Channel Blockers
references: Brain Res. 1982 Oct 28;250(1):71-92
references: 6128061
references: Cell. 2011 Nov 23;147(5):1159-70
references: 22100643
references: Brain Res. 1971 Nov;34(1):171-5
references: 5124915
references: Hippocampus. 2005;15(7):841-52
references: 16145692
references: Neurosci Lett. 2000 Feb 4;279(3):177-80
references: 10688058
references: J Physiol. 1982 Sep;330:537-72
references: 6294290
references: J Neurosci. 2011 Aug 24;31(34):12282-96
references: 21865471
references: Proc Natl Acad Sci U S A. 2009 Jul 14;106(28):11794-9
references: 19561297
references: Neuron. 2006 Jan 19;49(2):257-70
references: 16423699
references: Cell Physiol Biochem. 2009;24(5-6):325-34
references: 19910673
references: Neuron. 2012 Jan 26;73(2):235-47
references: 22284179
references: J Neurosci. 2012 Mar 14;32(11):3736-47
references: 22423094
references: Neuron. 2012 Nov 21;76(4):776-89
references: 23177962
references: J Physiol. 2002 Dec 15;545(3):783-805
references: 12482886
references: Neuron. 2011 Nov 17;72(4):643-53
references: 22099465
references: Nat Rev Neurosci. 2000 Oct;1(1):21-30
references: 11252765
references: J Physiol. 2014 Feb 15;592(4):669-93
references: 24366266
references: Nature. 2007 Jan 11;445(7124):168-76
references: 17151600
references: Neuron. 2010 Jan 14;65(1):7-19
references: 20152109
references: J Comp Neurol. 1977 Mar 1;172(1):49-84
references: 65364
references: Proc Natl Acad Sci U S A. 2008 Jun 3;105(22):7869-74
references: 18515424
references: J Comp Neurol. 1998 Aug 17;398(1):49-82
references: 9703027
references: Nature. 1980 Feb 14;283(5748):673-6
references: 6965523
references: J Neurosci. 2006 Mar 8;26(10):2599-613
references: 16525039
references: Prog Brain Res. 1990;83:161-87
references: 2203097
references: Nat Neurosci. 2009 May;12(5):577-84
references: 19363490
references: Neuron. 2014 Sep 17;83(6):1418-30
references: 25199704
references: J Physiol. 1989 Feb;409:171-90
references: 2585290
references: J Neurosci. 2004 Feb 4;24(5):1236-44
references: 14762142
references: Nature. 2006 Jun 8;441(7094):761-5
references: 16625207
references: Nature. 2005 Aug 11;436(7052):801-6
references: 15965463
references: Proc Natl Acad Sci U S A. 2006 Jun 6;103(23):8870-5
references: 16735477
references: J Biol Chem. 2007 Aug 17;282(33):23899-909
references: 17561493
references: J Neurosci. 2009 Jun 10;29(23):7625-30
references: 19515931
references: Hippocampus. 2014 Mar;24(3):249-56
references: 24638961
references: Neuron. 2008 Dec 10;60(5):875-89
references: 19081381
references: Brain Dev. 2004 Jun;26(4):213-8
references: 15130686
references: Proc Natl Acad Sci U S A. 2000 Jul 5;97(14):8110-5
references: 10859358
references: Hippocampus. 2004;14(8):935-47
references: 15390177
references: Nat Neurosci. 2011 Jun 12;14(7):840-7
references: 21666672
references: Neuron. 2012 Sep 20;75(6):1081-93
references: 22998875
references: J Neurosci. 2010 Feb 3;30(5):1777-87
references: 20130187
references: Trends Neurosci. 2000 May;23(5):216-22
references: 10782127
references: J Neurosci. 2012 Feb 8;32(6):2166-81
references: 22323729
references: Science. 2007 Mar 23;315(5819):1719-22
references: 17379810
references: J Neurosci. 2009 Nov 18;29(46):14472-83
references: 19923281
references: Biol Cybern. 1984;50(1):15-33
references: 6324889
references: J Physiol. 2006 May 15;573(Pt 1):17-34
references: 16527853
references: J Neurosci. 2013 May 8;33(19):8494-503
references: 23658186
references: J Neurosci. 2007 May 23;27(21):5757-65
references: 17522319
references: Hippocampus. 1993 Jul;3(3):317-30
references: 8353611
references: J Physiol. 2006 Oct 1;576(Pt 1):235-56
references: 16840518
references: Science. 2008 Jul 4;321(5885):140-3
references: 18599792
references: J Physiol. 2009 Feb 15;587(Pt 4):713-9
references: 19218620
references: J Neurosci. 2014 Mar 5;34(10):3719-32
references: 24599470
references: J Physiol. 2011 Aug 1;589(Pt 15):3753-73
references: 21624967
references: Prog Neurobiol. 1989;33(3):161-253
references: 2682783
references: Biophys J. 2007 Apr 15;92(8):2747-56
references: 17237198
references: J Neurosci. 2004 May 12;24(19):4614-24
references: 15140933
references: Science. 1998 Dec 4;282(5395):1890-3
references: 9836639
references: J Neurosci. 1994 Dec;14(12):7347-56
references: 7996180
references: J Biol Chem. 2012 May 18;287(21):17656-17661
references: 22511771
references: Neurosci Biobehav Rev. 2004 May;28(3):273-83
references: 15225971
references: J Physiol. 2012 Aug 15;590(16):3953-64
references: 22674722
references: Science. 1996 Jun 7;272(5267):1484-6
references: 8633241
references: J Physiol. 2005 Aug 1;566(Pt 3):689-715
references: 15890705
references: J Biol Chem. 2000 Aug 4;275(31):24089-95
references: 10816588
references: J Neurophysiol. 2008 Nov;100(5):2589-604
references: 18684909
references: J Physiol. 2002 Oct 1;544(Pt 1):29-37
references: 12356878
references: Nat Neurosci. 2005 Jan;8(1):51-60
references: 15608631
references: J Neurosci. 2007 Feb 21;27(8):1853-67
references: 17314282
references: Nat Neurosci. 2011 Aug 07;14(9):1174-81
references: 21822270
references: J Neurosci. 2001 Aug 1;21(15):5535-45
references: 11466425
references: Brain Res. 1986 Jul 16;378(1):169-73
references: 3742197
references: J Neurophysiol. 2013 Apr;109(7):1940-53
references: 23324324
references: Hippocampus. 1998;8(6):608-19
references: 9882018
references: J R Soc Interface. 2014 Oct 6;11(99):
references: 25100320
references: J Physiol. 1984 Sep;354:319-31
references: 6434729
references: J Physiol. 2011 Nov 1;589(Pt 21):5125-42
references: 21911608
references: J Physiol. 2012 Nov 15;590(22):5707-22
references: 22988138