Inhibition dominates in shaping spontaneous CA3 hippocampal network activities in vitro

Hippocampus - Tập 19 Số 2 - Trang 152-165 - 2009
Ernest C. Y. Ho1,2, Liang Zhang3,2, Frances K. Skinner3,1,4,2
1Department of Physiology, University of Toronto, Toronto, Ontario, Canada
2Toronto Western Research Institute, University Health Network, Toronto, Ontario, Canada
3Department of Medicine (Neurology), University of Toronto, Toronto, Ontario, Canada
4Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada

Tóm tắt

AbstractWe have assessed the balance of excitation and inhibition in in vitro rodent hippocampal slices exhibiting spontaneous, basal sharp waves (bSPWs). A defining signature of a network exhibiting bSPWs is the rise and fall in local field activities with frequencies ranging from 0.5 to 4.5 Hz. This variation of extracellular local field activities manifests at the intracellular level as postsynaptic potentials (PSPs). In correspondence with the local field bSPWs, we consider “sparse” and “synchronous” parts of bSPWs at the intracellular level. We have used intracellular data of bSPW‐associated PSPs together with mathematical extraction techniques to quantify the mean and variance of synaptic conductances that a neuron experiences during bSPW episodes. We find that inhibitory conductances dominate in pyramidal cells and in a putative interneuron, and that inhibitory variances are much greater than excitatory ones during synchronous parts of bSPWs. Specifically, we find that there is at least a twofold increase in inhibitory conductance dominance from “sparse” to “synchronous” bSPW states and that this transition is associated with inhibitory fluctuations of greater than 10% of the change in mean inhibitory conductance. On the basis of our findings, we suggest that such inhibitory fluctuations during transition may be a physiological feature of systems expressing such population activities. In summary, our results provide a quantified basis for understanding the interaction of excitatory and inhibitory neuronal subpopulations in bSPW activities. © 2008 Wiley‐Liss, Inc.

Từ khóa


Tài liệu tham khảo

Behrends CJ, 2005, Induction of sharp wave‐ripple complexes in vitro and reorganization of hippocampal networks, Nature Neurosci, 8, 1560, 10.1038/nn1571

10.1126/science.1134960

10.1093/acprof:oso/9780195301069.001.0001

10.1038/nn1105-1418

10.1038/30735

10.1111/j.1469-7793.2000.00485.x

10.1113/jphysiol.2004.068080

10.1016/S0306-4522(01)00344-X

10.1038/nrn1198

10.1016/S0896-6273(00)00133-1

10.1016/j.jneumeth.2005.03.006

10.1016/j.neuroscience.2007.05.016

10.1523/JNEUROSCI.5297-05.2006

10.1093/brain/121.6.1073

10.1152/jn.00542.2002

10.1113/jphysiol.2002.017624

10.1113/jphysiol.2003.044602

10.1038/35049047

10.1016/S0896-6273(03)00064-3

10.1016/S0304-3940(01)02505-8

10.1152/jn.01223.2003

10.1152/jn.01313.2004

10.1523/JNEUROSCI.4652-06.2007

10.1126/science.6695179

10.1111/j.1528-1157.1986.tb03578.x

10.1038/nature01616

10.1523/JNEUROSCI.23-32-10388.2003

10.1152/jn.1993.70.2.781

10.1016/S0306-4522(00)00318-3

10.1016/j.neuroscience.2005.04.019

10.1113/jphysiol.2001.013441

10.1152/jn.00806.2004

10.1152/jn.00086.2005

10.1113/jphysiol.2006.114918

10.1002/hipo.20389

Thông tin
Thông tin xuất bản

Hippocampus

Tập 19 Số 2

152-165

Thông tin tác giả