title: Developmental Changes in Electrophysiological Properties and a Transition from Electrical to Chemical Coupling between Excitatory Layer 4 Neurons in the Rat Barrel Cortex.
abstract: During development, sensory systems switch from an immature to an adult mode of function along with the emergence of the active cortical states. Here, we used patch-clamp recordings from neocortical slices in vitro to characterize the developmental changes in the basic electrophysiological properties of excitatory L4 neurons and their connectivity before and after the developmental switch, which occurs in the rat barrel cortex in vivo at postnatal day P8. Prior to the switch, L4 neurons had higher resting membrane potentials, higher input resistance, lower membrane capacity, as well as action potentials (APs) with smaller amplitudes, longer durations and higher AP thresholds compared to the neurons after the switch. A sustained firing pattern also emerged around the switch. Dual patch-clamp recordings from L4 neurons revealed that recurrent connections between L4 excitatory cells do not exist before and develop rapidly across the switch. In contrast, electrical coupling between these neurons waned around the switch. We suggest that maturation of electrophysiological features, particularly acquisition of a sustained firing pattern, and a transition from the immature electrical to mature chemical synaptic coupling between excitatory L4 neurons, contributes to the developmental switch in the cortical mode of function.
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Fliza
authors.initials: F
authors.lastname: Valiullina
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Dinara
authors.initials: D
authors.lastname: Akhmetshina
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Azat
authors.initials: A
authors.lastname: Nasretdinov
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Marat
authors.initials: M
authors.lastname: Mukhtarov
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Guzel
authors.initials: G
authors.lastname: Valeeva
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal UniversityKazan, Russia; Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale UMR901Marseille, France; Aix-Marseille UniversityMarseille, France.
authors.forename: Roustem
authors.initials: R
authors.lastname: Khazipov
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal UniversityKazan, Russia; Department of Physiology and Pathophysiology, University of HeidelbergHeidelberg, Germany.
authors.forename: Andrei
authors.initials: A
authors.lastname: Rozov
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D055592:Biophysical Phenomena / Q000502:physiology*; D004558:Electric Stimulation; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D066298:In Vitro Techniques; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D017729:Presynaptic Terminals / Q000502:physiology; D051381:Rats; D013003:Somatosensory Cortex / Q000166:cytology* / Q000254:growth & development*; D018709:Statistics, Nonparametric; D013569:Synapses / Q000145:classification / Q000502:physiology*
keywords: barrel cortex; critical period; development; excitation; gap junctions
references.citation: Front Neuroanat. 2012 Jul 11;6:24
references.pmid: 22798946
references.citation: Cereb Cortex. 2003 Jun;13(6):661-9
references.pmid: 12764042
references.citation: Science. 1992 Jul 31;257(5070):665-9
references.pmid: 1496379
references.citation: Cereb Cortex. 2007 Jul;17(7):1582-94
references.pmid: 16950867
references.citation: Nature. 2014 Jul 24;511(7510):471-4
references.pmid: 24828045
references.citation: Nat Rev Neurosci. 2010 Jan;11(1):18-29
references.pmid: 19953103
references.citation: Annu Rev Physiol. 2002;64:355-405
references.pmid: 11826273
references.citation: J Neurosci. 1993 Dec;13(12):5365-82
references.pmid: 8254380
references.citation: Brain Res Dev Brain Res. 1990 Nov 1;56(2):229-34
references.pmid: 2261684
references.citation: J Physiol. 1999 Nov 15;521 Pt 1:169-90
references.pmid: 10562343
references.citation: J Neurophysiol. 2002 Jun;87(6):2904-14
references.pmid: 12037194
references.citation: Neuron. 2013 Sep 4;79(5):970-86
references.pmid: 24012009
references.citation: Neuron. 2014 Apr 16;82(2):365-79
references.pmid: 24685175
references.citation: Science. 2011 Oct 14;334(6053):226-9
references.pmid: 21998388
references.citation: Front Neuroanat. 2009 Nov 17;3:27
references.pmid: 19949463
references.citation: Neurosci Lett. 1979 Dec;15(2-3):115-9
references.pmid: 530521
references.citation: Dev Neurosci. 1998;20(1):59-64
references.pmid: 9600391
references.citation: Neuroscience. 1991;41(2-3):365-79
references.pmid: 1870696
references.citation: J Comp Neurol. 1985 Jun 22;236(4):477-95
references.pmid: 4056099
references.citation: J Neurosci. 1995 Jan;15(1 Pt 2):549-61
references.pmid: 7823163
references.citation: Neuron. 2007 Oct 25;56(2):339-55
references.pmid: 17964250
references.citation: Cereb Cortex. 2016 Feb;26(2):838-54
references.pmid: 26574502
references.citation: Bull Exp Biol Med. 2014 Jan;156(3):295-8
references.pmid: 24771360
references.citation: Neurophysiol Clin. 2010 May;40(2):59-124
references.pmid: 20510792
references.citation: Eur J Neurosci. 2012 May;35(10):1540-53
references.pmid: 22607000
references.citation: Cereb Cortex. 2004 Jun;14(6):690-701
references.pmid: 15054049
references.citation: Neuron. 2009 Jan 29;61(2):301-16
references.pmid: 19186171
references.citation: Neuron. 2010 Aug 12;67(3):480-98
references.pmid: 20696384
references.citation: Cereb Cortex. 2015 Oct;25(10):3458-67
references.pmid: 25100857
references.citation: Neuroscience. 2013 Oct 10;250:240-52
references.pmid: 23872391
references.citation: Neuroimage. 2012 Oct 1;62(4):2212-21
references.pmid: 22387472
references.citation: Trends Neurosci. 2006 Jul;29(7):414-8
references.pmid: 16713634
references.citation: Prog Neurobiol. 2013 Apr;103:3-27
references.pmid: 23195880
references.citation: J Neurophysiol. 2007 Jan;97(1):692-700
references.pmid: 17093125
references.citation: J Physiol. 2002 Aug 15;543(Pt 1):49-70
references.pmid: 12181281
references.citation: Cereb Cortex. 2015 Aug;25(8):2255-66
references.pmid: 24610243
references.citation: J Physiol. 1997 Dec 15;505 ( Pt 3):617-32
references.pmid: 9457640
references.citation: Nat Neurosci. 2007 Apr;10(4):453-61
references.pmid: 17351636
references.citation: Ann Clin Transl Neurol. 2014 Jan;1(1):15-26
references.pmid: 25356379
references.citation: Physiol Rev. 2005 Jul;85(3):883-941
references.pmid: 15987798
references.citation: J Neurosci. 2012 May 2;32(18):6183-96
references.pmid: 22553025
references.citation: J Neurosci. 2012 Jul 11;32(28):9511-6
references.pmid: 22787036
references.citation: Proc Natl Acad Sci U S A. 2000 Aug 29;97(18):10260-5
references.pmid: 10944183
references.citation: J Neurosci. 2000 Oct 15;20(20):7579-86
references.pmid: 11027217
references.citation: Curr Biol. 2012 Nov 6;22(21):2075-80
references.pmid: 23084988
references.citation: J Neurosci. 2003 Sep 24;23(25):8759-70
references.pmid: 14507976
references.citation: Science. 2006 Jun 16;312(5780):1622-7
references.pmid: 16778049
references.citation: Nature. 2012 Jun 7;486(7401):113-7
references.pmid: 22678291
references.citation: J Neurosci. 1997 May 1;17(9):3096-111
references.pmid: 9096144
references.citation: Cereb Cortex. 2009 Mar;19(3):688-96
references.pmid: 18663251
references.citation: J Comp Neurol. 1986 Nov 15;253(3):303-14
references.pmid: 3793995
references.citation: J Neurophysiol. 2011 Jun;105(6):2976-88
references.pmid: 21451062
references.citation: Cereb Cortex. 2013 Jun;23(6):1299-316
references.pmid: 22593243
references.citation: Nature. 2004 Dec 9;432(7018):758-61
references.pmid: 15592414
references.citation: J Neurophysiol. 2001 Feb;85(2):620-9
references.pmid: 11160498
references.citation: J Physiol. 1999 Jun 15;517 ( Pt 3):791-804
references.pmid: 10358119
references.citation: Nature. 2006 Jan 5;439(7072):79-83
references.pmid: 16327778
references.citation: J Neurosci. 2000 Jul 15;20(14):5300-11
references.pmid: 10884314
references.citation: J Neurosci. 2009 Jul 15;29(28):9011-25
references.pmid: 19605639
references.citation: Neuron. 1993 Jan;10(1):103-14
references.pmid: 8427699
references.citation: Neuron. 1997 Feb;18(2):269-80
references.pmid: 9052797
references.citation: Neuron. 2007 Apr 5;54(1):105-20
references.pmid: 17408581