It was reported previously that repeated brief tetanization of the posterior eight nerve can produce long-term homosynaptic potentiations of the electrotonic and chemical components of the mixed EPSP evoked in the Mauthner cell lateral dendrite by a single stimulus to the nerve. We show here that the same stimulus paradigm can lead, alternatively, to short-term enhancements of both excitatory r...

background: ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. the mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. we aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex b...

Interaction between tetanus long-term potentiation and hypoxia-induced potentiation in the rat hippocampus. J. Neurophysiol. 78: 2475-2482, 1997. The interaction between tetanus-induced long-term potentiation (LTP) and hypoxia-induced potentiation was investigated by performing extracellular recordings in the CA1 region of rat hippocampus using a two-pathway design. Hippocampal slices were plac...

Propofol is a widely used intravenous general anesthetic. Propofol-induced unconsciousness in humans is associated with inhibition of thalamic activity evoked by somatosensory stimuli. However, the cellular mechanisms underlying the effects of propofol in thalamic circuits are largely unknown. We investigated the influence of propofol on synaptic responsiveness of thalamocortical relay neurons ...

Long-term potentiation (LTP) is often induced experimentally by continuous high-frequency afferent stimulation (HFS), typically at 100 Hz for 1 s. Induction of LTP requires postsynaptic depolarization and voltage-dependent calcium influx. Induction is more effective if the same number of stimuli are given as a series of short bursts rather than as continuous HFS, in part because excitatory post...

In chemical synapses information flow is polarized. However, the postsynaptic cells can affect transmitter release via retrograde chemical signaling. Here we explored the hypothesis that, in large synapses, having large synaptic cleft resistance, transmitter release can be enhanced by electrical (ephaptic) signaling due to depolarization of the presynaptic release site induced by the excitatory...

Long-term potentiation (LTP) of synaptic strength at Schaffer collateral synapses has largely been attributed to changes in the number and biophysical properties of AMPA receptors (AMPARs). Small-conductance Ca21-activated K1 channels (SK2 channels) are functionally coupled with NMDA receptors (NMDARs) in CA1 spines such that their activity modulates the shape of excitatory postsynaptic potenti...

context the current study aimed to review research articles concerning cortical representational plasticity following the manipulations of inputs. evidence acquisition this review article compromised previous studies in pubmed, google scholar and scientific information databases according to the keywords since 1988. results ca1 neurons depolarization paired with ca3 presynaptic input result in ...

Reyes FD, Walters ET. Long-lasting synaptic potentiation induced by depolarization under conditions that eliminate detectable Ca signals. J Neurophysiol 103: 1283–1294, 2010. First published December 30, 2009; doi:10.1152/jn.00704.2009. Activity-dependent alterations of synaptic transmission important for learning and memory are often induced by Ca signals generated by depolarization. While it ...

CA3-CA3 recurrent excitatory synapses are thought to play a key role in memory storage and pattern completion. Whether the plasticity properties of these synapses are consistent with their proposed network functions remains unclear. Here, we examine the properties of spike timing-dependent plasticity (STDP) at CA3-CA3 synapses. Low-frequency pairing of excitatory postsynaptic potentials (EPSPs)...