The rat gracile nucleus in vitro: II. Field potentials and their conditioned depression

AbstractAimAn early characterization of drug-induced cardiotoxicity may be possible by combining comprehensive in vitro pro-arrhythmia assay and deep learning techniques. The goal of this study was to develop a deep learning method to automatically detect irregular beating rhythm as well as abnormal waveforms of field potentials in an in vitro cardiotoxicity assay using human pluripotent stem cell (hPSC) derived cardiomyocytes and multi-electrode array (MEA) system.Methods and ResultsWe included field potential waveforms from 380 experiments which obtained by application of some cardioactive drugs on healthy and/or patient-specific induced pluripotent stem cells derived cardiomyocytes (iPSC-CM). We employed convolutional and recurrent neural networks, in order to develop a new method for automatic classification of field potential recordings without using any hand-engineered features. In the proposed method, a preparation phase was initially applied to split 60-second long recordings into a series of 5-second long windows. Thereafter, the classification phase comprising of two main steps was designed. In the first step, 5-second long windows were classified using a designated convolutional neural network (CNN). In the second step, the results of 5-second long window assessments were used as the input sequence to a recurrent neural network (RNN). The output was then compared to electrophysiologist-level arrhythmia (irregularity or abnormal waveforms) detection, resulting in 0.84 accuracy, 0.84 sensitivity, 0.85 specificity, and 0.88 precision.ConclusionA novel deep learning approach based on a two-step CNN-RNN method can be used for automated analysis of “irregularity or abnormal waveforms” in an in vitro model of cardiotoxicity experiments.

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Synaptic and intrinsic responses of medical entorhinal cortical cells in normal and magnesium-free medium in vitro

Journal of Neurophysiology ◽

10.1152/jn.1988.59.5.1476 ◽

1988 ◽

Vol 59 (5) ◽

pp. 1476-1496 ◽

Cited By ~ 190

Author(s):

R. S. Jones ◽

U. Heinemann

Keyword(s):

Entorhinal Cortex ◽

Action Potentials ◽

Membrane Conductance ◽

Nmda Receptor Antagonist ◽

Field Potentials ◽

Cortical Cells ◽

Medial Entorhinal Cortex ◽

Membrane Hyperpolarization

1. Extracellular recordings were made from slices of hippocampus plus parahippocampal regions maintained in vitro. Field potentials, recorded in the entorhinal cortex after stimulation in the subiculum, resembled those observed in vivo. 2. Washout of magnesium from the slices resulted in paroxysmal events which resembled those occurring during sustained seizures in vivo. These events were greatest in amplitude and duration in layers IV/V of the medial entorhinal cortex and could occur both spontaneously and in response to subicular stimulation. Spontaneous seizure-like events were not prevented by severing the connections between the hippocampus and entorhinal cortex, but much smaller and shorter events occurring in the dentate gyrus were stopped by this manipulation. Both spontaneous and evoked paroxysmal events were blocked by perfusion with the N-methyl-D-aspartate (NMDA) receptor antagonist, DL-2-amino-5-phosphonovalerate (2-AP5). 3. Neurons in layers IV/V were characterized by intracellular recording. Injection of depolarizing current in most cells evoked a train of nondecrementing action potentials with only weak spike frequency accommodation and little or no posttrain after hyperpolarization. 4. A small number of cells displayed burst response when depolarized by positive current. The burst consisted of a slow depolarization with superimposed action potentials which decreased in amplitude and increased in duration during the discharge. The burst was terminated by a strong after hyperpolarization and thereafter, during prolonged current pulses a train of nondecrementing spikes occurred. The burst response remained if the cell was held at hyperpolarized levels but was inactivated by holding the cell at a depolarized level. 5. Depolarizing synaptic potentials could be evoked by stimulation in the subiculum. A delayed and prolonged depolarization clearly decremented with membrane hyperpolarization and, occasionally, increased with depolarization. 6. Washout of magnesium from the slices resulted in an enhancement of the late depolarization and a reversal of its voltage dependence. Eventually a single shock to the subiculum evoked a large all-or-none paroxysmal depolarization associated with a massive increase in membrane conductance. Similar events occurred spontaneously in all cells tested. The paroxysmal depolarizations, both spontaneous and evoked, were rapidly blocked by 2-AP5. 7. It is concluded that medial entorhinal cortical cells possess several intrinsic and synaptic properties which confer an extreme susceptibility to generation of sustained seizure activity.(ABSTRACT TRUNCATED AT 400 WORDS)

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Effects of deprolorphin, a casomorphin analog, on hippocampal CA1 field potentials in vitro

Peptides ◽

10.1016/0196-9781(83)90133-x ◽

1983 ◽

Vol 4 (3) ◽

pp. 283-286 ◽

Cited By ~ 2

Author(s):

Klaus G. Reymann ◽

Aisa N. Chepkova ◽

Hansjürgen Matthies

Keyword(s):

Field Potentials ◽

Hippocampal Ca1 ◽

Hippocampal Ca1 Field

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Unilateral inner ear damage results in lasting changes in hippocampal CA1 field potentials in vitro

Hippocampus ◽

10.1002/hipo.10174 ◽

2003 ◽

Vol 13 (8) ◽

pp. 873-878 ◽

Cited By ~ 27

Author(s):

Yiwen Zheng ◽

D. Steven Kerr ◽

Cynthia L. Darlington ◽

Paul F. Smith

Keyword(s):

Inner Ear ◽

Field Potentials ◽

Hippocampal Ca1 ◽

Hippocampal Ca1 Field ◽

Inner Ear Damage

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Estimating the Effects of Nanoparticles on Neuronal Field Potentials Based on Their Effects on Single Neurons In Vitro

Neuromethods - Use of Nanoparticles in Neuroscience ◽

10.1007/978-1-4939-7584-6_10 ◽

2018 ◽

pp. 149-169

Author(s):

Michael Busse ◽

Narsis Salafzoon ◽

Annette Kraegeloh ◽

David R. Stevens ◽

Daniel J. Strauss

Keyword(s):

Field Potentials ◽

Single Neurons

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Morphine excitation: Effects on field potentials recorded in the in vitro hippocampal slice

Neuropharmacology ◽

10.1016/0028-3908(80)90019-2 ◽

1980 ◽

Vol 19 (6) ◽

pp. 507-514 ◽

Cited By ~ 33

Author(s):

J.H. Robinson ◽

S.A. Deadwyler

Keyword(s):

Hippocampal Slice ◽

Field Potentials

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Field potentials from the frog optic tectum in vitro

Brain Research Bulletin ◽

10.1016/0361-9230(86)90188-7 ◽

1986 ◽

Vol 16 (4) ◽

pp. 553-556 ◽

Cited By ~ 5

Author(s):

L. Sivilottp

Keyword(s):

Optic Tectum ◽

Field Potentials

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An in vitro study of retinotectal transmission in the chick: Role of glutamate and GABA in evoked field potentials

Visual Neuroscience ◽

10.1017/s0952523800008622 ◽

1996 ◽

Vol 13 (4) ◽

pp. 747-758 ◽

Cited By ~ 21

Author(s):

J. C. Dye ◽

H. J. Karten

Keyword(s):

Optic Nerve ◽

Field Potential ◽

In Vitro Study ◽

Bipolar Electrode ◽

Field Potentials ◽

Negative Wave ◽

Evoked Field Potentials ◽

Thin Slices ◽

Retinal Afferents

AbstractWe have developed two brain slice preparations for studying tectofugal visual pathways in the chick: conventional, 400-μm slices (“thin slices”), and “thick slices” which encompass the rostral pole of the optic tectum and the contralateral optic nerve. Stimulation was delivered with a bipolar electrode positioned in stratum opticum in thin slices and in the contralateral optic nerve in thick slices. While the latter preparation provided a means of exclusively and unambiguously activating retinal afferents, several lines of evidence also indicated that the evoked field potentials in thin slices were chiefly consequent to retinal afferent excitation: (1) the similarity of evoked field potentials in thin slices to those in thick slice preparations; (2) their precise localization in retinorecipient layers as shown by prelabeling from retina with FITC-coupled cholera toxin; (3) transmission delays appropriate for retinal afferents as established with the thick slice preparation; (4) patterns of labeled afferents resulting from applications of Dil crystals to slices fixed after recording; and (5) the similarity in transmitter pharmacology between thin and thick slice preparations. Pharmacological manipulations carried out with bath-applied antagonists indicated that glutamate is the principal retinotectal transmitter. The broadly active glutamate receptor blocker, kynurenic acid, reversibly eliminated the postsynaptic component of the field potential as confirmed with 0 Ca2+ saline. A complete block was also effected by the non-NMDA antagonists CNQX and DNQX. The specific NMDA antagonist, APS, caused a smaller and variable reduction in response amplitude. The GABA antagonist, bicuculline, caused a prolongation of the monosynaptic field epsp in retinorecipient layers and an enhancement of the long-latency, negative wave in cellular layers below, supporting a late, excitation-limiting role for this inhibitory transmitter.

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