Induction of long-term depression and potentiation by low- and high-frequency stimulation in the dentate area of the anesthetized rat: magnitude, time course and EEG
Brain ResearchPublished 1 March 1987
Clive R. Bramham, Bolek Srebro
Citations68
SJR quartileQ2
SJR score0.85
SNIP0.72
Generate an AI Snapshot to get a quick, structured summary of this paper.
Study Snapshot
ObjectiveStudy objective
MethodsResearch methodology
PopulationPopulation studied
Sample sizeSample sizes
OutcomesStudy outcomes here
ResultsStudy results comes here
LimitationsResearch study limitations comes here
A concise AI-generated summary of the paper will appear here once you click Generate AI Snapshot.
TL;DR
Changes in the relationship between the EPSP and population spike amplitude indicated that granule cell excitability was enhanced during LTP and reduced during LTD, and it was found that LTP evoked by high-frequency stimulation was larger and generally reached peak magnitude faster than when it followed low- frequencies.
Abstract
We investigated the possible importance of stimulus train frequency for the induction and magnitude of long-term synaptic plasticity in the perforant path-granule cell pathway. Under the same experimental conditions, low- (15 Hz) or high-frequency (400 Hz) stimulation could elicit a profound long-term depression (LTD), or typical long-term potentiation (LTP), of the population spike amplitude, excitatory postsynaptic potential (EPSP) amplitude and spike onset latency. In addition, changes in the relationship between the EPSP and population spike amplitude indicated that granule cell excitability was enhanced during LTP and reduced during LTD. LTD occurred primarily after low-frequency stimulation (5 of 6 cases), and was always accompanied by striking changes in the EEG, most notably a biphasic slow potential. While the EEG changes were confined to the first 5 min after the tetanus, LTD lasted from 1 to 4 h. The nature of the EEG events is still unclear, it is suggested that they may represent a spreading depression-like episode. Finally, we found that LTP evoked by high-frequency stimulation was larger and generally reached peak magnitude faster than when it followed low-frequency stimulation. A possible mechanism and role for hippocampal LTD is proposed.
Keywords
Neuroscience
The Journal of PhysiologyLong‐lasting potentiation of synaptic transmission in the dentate area of the anaesthetized rabbit following stimulation of the perforant path
7,290 Citations1973T.V.P. Bliss, Terje Lømo
The after‐effects of repetitive stimulation of the perforant path fibres to the dentate area of the hippocampal formation have been examined with extracellular micro‐electrodes in rabbits anaesthetized with urethane.
ScienceBlockade of <i>N</i> -Methyl-D-Aspartate Receptors May Protect Against Ischemic Damage in the Brain
1,688 Citations1984R. P. Simon, J. H. Swan +2 more
In rats ischemia of the forebrain induced by a 30-minute occlusion of the carotid artery, followed by 120 minutes of arterial reperfusion, produced ischemic lesions of selectively vulnerable pyramidal cells in both hippocampi.
ScienceThe Biochemistry of Memory: A New and Specific Hypothesis
1,045 Citations1984Gary Lynch, M Baudry
A synaptic process with properties required for an intermediate step in memory storage is uncovered and hypothesized to be responsible for those forms of memory localized in the telencephalon.
Brain ResearchPatterned stimulation at the theta frequency is optimal for the induction of hippocampal long-term potentiation
1,039 Citations1986John Larson, Darryl Wong +1 more
The results indicate that patterns of stimulation resembling spike discharge patterns of hippocampal neurons in animals in exploratory situations are effective in inducing LTP and suggest temporal constraints on the mechanisms involved in triggering synaptic plasticity.
Journal of NeuroscienceSynaptic release of excitatory amino acid neurotransmitter mediates anoxic neuronal death
891 Citations1984SM Rothman
Results provide convincing evidence that the synaptic release of excitatory transmitter mediates the death of anoxic neurons, and suggests new strategies that may be effective in preventing the devastating insults produced by cerebral hypoxia and ischemia in man.
ScienceHypoglycemia-Induced Neuronal Damage Prevented by an <i>N</i> -Methyl-D-Aspartate Antagonist
672 Citations1985Tadeusz Wieloch
The results suggest that hypoglycemic neuronal damage is induced by NMDA receptor agonists, such as the excitatory amino acids or related compounds.
Brain ResearchSynaptic enhancement in fascia dentata: Cooperativity among coactive afferents
658 Citations1978B. L. McNaughton, R. M. Douglas +1 more
Evidence is presented that long-lasting enhancement of perforant path synapses following high-frequency activity is a cooperative process requiring coactivity of a considerable number of fibers.
Brain ResearchLong-term potentiation phenomena in the rat limbic forebrain
555 Citations1983R. Racine, Norton W. Milgram +1 more
The result indicates that the potentiation produced by kindling may be based upon the same mechanism as the LTP effect, and the effect of this potentiation on subsequent tests of short-term and long-term potentiation.
Brain ResearchLong-term potentiation of the perforant path-granule cell synapse in the rat hippocampus
505 Citations1975Robert M. Douglas, Graham V. Goddard
The results imply that the efficiency of synaptic transmission in the perforant path-granule cell synapse can be modified.
The Journal of PhysiologyLong‐term potentiation and depression of synaptic responses in the rat hippocampus: localization and frequency dependency.
472 Citations1978Thomas V. Dunwiddie, Gary Lynch
The results suggest that potentiated and heterosynaptic depression arise from different mechanisms, and that potentiation is confined to the set of terminals activated by a conditioning train, whereas the depression is generalized to the whole neurone.
Brain Research ReviewsLong-term potentiation as a candidate mnemonic device
373 Citations1984Timothy J. Teyler, Pascal DiScenna
It is argued that long-term potentiation is, currently, the most plausible device for subserving or initiating long- term information storage in the mammalian brain, and it is concluded that studying LTP within the context of behavioral learning and memory may provide new insights into the neurophysiological bases oflearning and memory.
The Journal of PhysiologyPossible mechanisms for long‐lasting potentiation of synaptic transmission in hippocampal slices from guinea‐pigs.
366 Citations1980P. Andersen, S. H. Sundberg +3 more
It is concluded that long‐lasting potentiation is specific to the pathway which has received the tetanization, and that the short‐lasting depression is not confined to any particular pathway but is a generalized (unspecific) phenomenon.
Brain ResearchLong-lasting facilitation of a synaptic potential following tetanization in thein vitro hippocampal slice
340 Citations1975Philip A. Schwartzkroin, Knut Wester
The facilitation phenomenon appeared to be specific to the synapse of stratum radiatum afferents onto CA1 pyramidal cells since: (1) stimulation outside the Radiatum layer did not produce the effect, (2) antidromic field potentials recorded in CA3 were unchanged, (3) EPSP threshold in CA1 was unchanged, and (4) alveus tetanization did not producing a facilitatory effect.
Life SciencesThe effects of repetitive low frequency stimulation on control and “potentiated” synaptic responses in the hippocampus
316 Citations1980Germán Barrionuevo, Frank Schottler +1 more
Trains of low frequency stimulation (LFS) were administered to the Schaffer collateral-commissural projections to the regio superior of the rat hippocampus before and after the induction of long-term potentiation (LTP).
Journal of NeurophysiologyAbnormal neuronal excitability in hippocampal slices from kindled rats
203 Citations1985Gregory L. King, Raymond Dingledine +2 more
It is concluded that either synapses or neurons intrinsic to the hippocampus are altered by kindling stimuli applied outside this brain area and the transient increase in inhibition in the dentate gyrus suggests that it may reflect a compensatory reaction to kindled seizures.
NatureAsymmetric relationships between homosynaptic long-term potentiation and heterosynaptic long-term depression
196 Citations1983Wickliffe C. Abraham, Graham V. Goddard
It is reported that tetanization of either MPP or LPP reliably depresses synaptic transmission in the other pathway for at least 3 h, considerably smaller than the usual magnitude of LTP, and was obtained regardless of whether LTP had been produced in the tetanized homosynaptic pathway.
Brain ResearchFunctional anatomy of limbic seizures: Focal discharges from medial entorhinal cortex in rat
191 Citations1983Robert C. Collins, Robert G. Tearse +1 more
These studies indicate that the dentate gyrus initially restricts the entry of seizures from entorhinal cortex into the rest of hippocampus, and as this is overcome there is rapid bilateral spread through the hippocampal formation with passive interruption of normal behavior.
EpilepsiaAmino Acid Neurotransmitters and New Approaches to Anticonvulsant Drug Action
178 Citations1984Brian S. Meldrum
NeuroscienceLong-term potentiation in the hippocampus
169 Citations1983L. L. Voronin
It is suggested that modifiable excitatory synapses necessary for learning have been identified in studies of long-term potentiation and are distinct from those of 'usual' short-term post-tetanic potentiation.
Canadian Journal of Physiology and PharmacologyChanges in extracellular Ca<sup>2+</sup> and K<sup>+</sup> activity accompanying hippocampal discharges
121 Citations1980K. Krnjević, Mary E. Morris +1 more
In rats under urethane anaesthesia, changes in the extracellular activities of K+ and Ca2+ (alpha K and alpha Ca) evoked by fimbrial or entorhinal stimulation and recorded in area CA3 with ion-selective microelectrodes are maximal in the pyramidal cell layers.
Journal of NeurophysiologyPotassium and calcium concentrations in interstitial fluid of hippocampal formation during paroxysmal responses
120 Citations1985George G. Somjen, J.L. Giacchino
It is concluded that tonic paroxysmal discharge of the granule cells is associated with an outflow of K ions from the cell somata, but not the dendrites, and that LD in hippocampal formation isassociated with more widespread depolarization of pyramidal andgranule cells than in cerebral neocortex and cerebellar cortex.
The Journal of PhysiologyHeterosynaptic changes accompany long‐term but not short‐term potentiation of the perforant path in the anaesthetized rat.
112 Citations1985Wickliffe C. Abraham, T.V.P. Bliss +1 more
Although effects of long‐term E‐S potentiation in rats anaesthetized with sodium pentobarbitone probably reflect a generalized post‐synaptic change, this change is unlikely to be a prolonged reduction in the membrane potential of granule cells.
Brain ResearchPotassium activity in rabbit cortex
106 Citations1974Kin J. Futamachi, Roberto Mutani +1 more
Measurements of extracellular potassium concentration were made in rabbit cortex using potassium-sensitive microelectrodes with a rapid response time and transient increases occurred following direct stimulation of normal cortex, during spreading depression (SD), and during interictal epileptiform discharges.
Experimental NeurologyMembrane potential of cerebral cortical cells during spreading depression and asphyxia
96 Citations1966H. Collewijn, A. Van Harreveld
Changes in membrane potential were recorded intracellularly from cortical cells during spreading depression (SD) and asphyxiation and a correction was made in a few instances for the effects of the slow potential change accompanying spreading depression on the membrane potential recorded between an intrACEllular and indifferent electrode.
Trends in NeurosciencesWhat is the mechanism of long-term potentiation in the hippocampus?
88 Citations1982Tim Bliss, Annette Dolphin
Brief trains of high-frequency stimulation, delivered to monosynaptic pathways in the hippocampus, can increase the amplitude of evoked potentials for several hours or even days, providing a dramatic mammalian model for the sort of enduring changes in synaptic efficacy which are widely assumed to form the neural substrate for learning and memory.
Experimental NeurologyHypothesis regarding the cellular mechanisms responsible for long-term synaptic potentiation in the hippocampus
85 Citations1980Michel Baudry, Gary Lynch
The multiple-stage hypothesis postulates that repetitive stimulaion causes an increase of intracellular calcium in the target dendritic regions which results in the activation of a membrane-associated protease which in turn exposes additional glutamate receptors.
Journal of NeurophysiologySustained potential shifts and paroxysmal discharges in hippocampal formation
68 Citations1985George G. Somjen, Peter G. Aitken +2 more
It is concluded that the synchronization of the action potentials fired by granule and pyramidal cells during paroxysmal discharge is probably due to electric interaction among the neurons.
Brain ResearchChanges in free calcium ion concentration recorded inside hippocampal pyramidal cells in situ
49 Citations1986K. Krnjević, Mary E. Morris +1 more
In rats under urethane or pentobarbitone anesthesia, Ca2+ -sensitive microelectrodes were inserted into CA3 and CA1 hippocampal cells, leading to substantial increases in [Ca]i, far greater than can be evoked by tetanic activation in spinal motoneurons.
Experimental NeurologyImportant factors in induction of long-term potentiation in thin hippocampal sections
30 Citations1981C. Yamamoto
The importance of the intensity of the tetanic stimulation suggests that LTP is induced as a result of coactivation of some critical number of presynaptic fibers.
Life SciencesVerapamil counteracts depression but not long-lasting potentiation of the hippocampal population spike
28 Citations1984B.R. Sastry, S.S. Chirwa +3 more
The results indicate that homosynaptic and heterosyaptic depressions are at least partly due to an accumulation of Ca++ into CA1 neurones, and an established LLP is not interrupted by LLP of another input.
Life SciencesLong-lasting potentiation in hippocampus is not due to an increase in glutamate receptors
21 Citations1984B.R. Sastry, Joanne W. Goh
Results indicate that the increase in the number of glutamate receptors is not a requirement for LLP and Verapamil (1 micron), which does not block long-lasting potentiation (LLP), counteracted the depression of the population spike as well as the associated increase in 3H-glutamate binding.
Behavioral BiologyA comparison of long-term potentiation in the in vitro and in vivo hippocampal preparations
20 Citations1977Timothy J. Teyler, Bradley E. Alger +2 more
Since the two preparations exhibited similar response properties, the results support the use of the hippocampal slice preparation as a model system for the study of neural mechanisms of plasticity.
Canadian Journal of Physiology and PharmacologyLow-frequency stimulation of the perforant path produces long-term potentiation in the dentate gyrus of unanesthetized rats
19 Citations1983R. W. Skelton, J.J. Miller +1 more
It is found that stimulation at 0.2 Hz, but not 0.04 Hz produced LTP, suggesting that the minimum stimulation frequency capable of producing LTP is lower than previously described.