Long-term maintenance of mature hippocampal slices in vitro

doi:10.1016/S0165-0270(00)00197-7

Journal of Neuroscience Methods

Volume 98, Issue 2, 1 June 2000, Pages 145-154

https://doi.org/10.1016/S0165-0270(00)00197-7 Get rights and content

Abstract

Cultures of primary neurons or thin brain slices are typically prepared from immature animals. We introduce a method to prepare hippocampal slice cultures from mature rats aged 20–30 days. Mature slice cultures retain hippocampal cytoarchitecture and synaptic connections up to 3 months in vitro. Spontaneous epileptiform activity is rarely observed suggesting long-term retention of normal neuronal excitability and of excitatory and inhibitory synaptic networks. Picrotoxin, a GABAergic Cl⁻ channel antagonist, induced characteristic interictal-like bursts that originated in the CA3 region, but not in the CA1 region. These data suggest that mature slice cultures displayed long-term retention of GABAergic inhibitory synapses that effectively suppressed synchronized burst activity via recurrent excitatory synapses of CA3 pyramidal cells. Mature slice cultures lack the reactive synaptogenesis, spontaneous epileptiform activity, and short life span that limit the use of slice cultures isolated from immature rats. Mature slice cultures are anticipated to be a useful addition for the in vitro study of normal and pathological hippocampal function.

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Citation Excerpt :
There is an ongoing debate as to whether OHSCs are more seizure prone than acute slices from age-matched animals. Both an increase in the incidence and a complete absence of epileptiform events have been described, depending on the culture methods and conditions during electrophysiological recording (McBain et al., 1989; Xiang et al., 2000; Dyhrfjeld-Johnsen et al., 2010; Berdichevsky et al., 2012). Little is known about the spontaneous network activity present during maintenance because, with few exceptions, OHSCs are not accessible for recordings while they are in the incubator (Stoppini et al., 1997; Thiebaud et al., 1997; Kristensen et al., 2001; Berdichevsky et al., 2010).
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¹: Present address: Department of Psychiatry, Mount Sinai School of Medicine, Gustave Levy Place, New York, NY 10029, USA.

²: Present address: Department of Physiology; New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA.

³: Present address: Department of Neuroscience, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA.

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Long-term maintenance of mature hippocampal slices in vitro

Abstract

Dev Brain Res

Neurosci Lett

Trends Neurosci

Brain Res

Brain Res

J Neurosci Methods

Dev Brain Res

Neurosci Res

J Neurosci Methods

Group I mGluR activation causes voltage-dependent and -independent Ca2+ rises in hippocampal pyramidal cells

J Neurophysiol

Group I mGluR activation causes voltage-dependent and -independent Ca²⁺ rises in hippocampal pyramidal cells