Long-term potentiation (LTP) of inhibitory synaptic transmission in rat visual cortex was investigated using intracellular recording in slice preparations. The inhibitory postsynaptic potential (IPSP) of layer V cells evoked monosynaptically by layer IV stimulation was recorded while excitatory postsynaptic potentials (EPSPs) were blocked by adding NMDA and non-NMDA receptor antagonists to the ...

Superfusion of hippocampal slices with 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 2-5 microM) reversibly blocked the Schaffer collateral and mossy fibre excitatory postsynaptic potential (EPSP), while sparing the fast and slow gamma-aminobutyric acid (GABA)-mediated inhibition. Membrane potential, input resistance and spike accommodation were not altered. Inward currents induced by quisqualate...

Low frequency stimulation (LFS, 1 Hz for 15 min) has been shown to produce an NMDA receptor dependent homosynaptic long-term depression (LTD) of synaptic potentials in the CA1 area of the rat hippocampus. Here we describe experiments aimed at characterizing EPSP/spike (E/S) coupling associated with this form of LTD. Our data show that following LFS neurons have a higher probability of synchrono...

Spike timing precision is a fundamental aspect of neuronal information processing in the brain. Here we examined the temporal precision of input-output operation of dentate granule cells (DGCs) in an animal model of temporal lobe epilepsy (TLE). In TLE, mossy fibers sprout and establish recurrent synapses on DGCs that generate aberrant slow kainate receptor-mediated excitatory postsynaptic pote...

We compared the transient increase of Ca2+ in single spines on basal dendrites of rat neocortical layer 5 pyramidal neurons evoked by subthreshold excitatory postsynaptic potentials (EPSPs) and back-propagating action potentials (APs) by using calcium fluorescence imaging. AP-evoked Ca2+ transients were detected in both the spines and in the adjacent dendritic shaft, whereas Ca2+ transients evo...

Intoxicating concentrations of ethanol inhibit N-methyl-d-aspartate (NMDA) receptor-dependent long-term potentiation, an interaction thought to underlie a major component of the central nervous system actions of ethanol. Another form of synaptic potentiation involving activation of L-type dihydropyridine-sensitive voltage-gated calcium channels (VGCCs) has been described, but very little inform...

Messaoudi, Elhoucine, Kjetil Bårdsen, Bolek Srebro, and Clive knockout mice (Korte et al. 1995; Patterson et al. 1996) R. Bramham. Acute intrahippocampal infusion of BDNF induces as well as in slices pretreated with TrkB-IgG, a BDNFlasting potentiation of synaptic transmission in the rat dentate scavenging fusion protein (Figurov et al. 1996). gyrus. J. Neurophysiol. 79: 496–499, 1998. The effe...

Manganese (Mn(2+))-enhanced magnetic resonance imaging (MEMRI) offers the possibility to generate longitudinal maps of brain activity in unrestrained and behaving animals. However, Mn(2+) is a metabolic toxin and a competitive inhibitor for Ca(2+), and therefore, a yet unsolved question in MEMRI studies is whether the concentrations of metal ion used may alter brain physiology. In the present w...

The conditions responsible for the associative properties of long-term potentiation (LTP) were examined in the CA1 region of the hippocampal slice preparation. Intracellularly recorded EPSPs resulting from single-volley stimulation at low frequency (0.15-0.1 Hz) in the stratum radiatum or oriens were paired with depolarizing current pulses (50-100 msec) injected through the recording microelect...

Synaptic transmission was measured at visualized terminal varicosities of the motor axon providing the sole excitatory innervation of the "opener" muscle in walking legs of crayfish (Procambarus clarkii Girard). Two questions were addressed: 1) How uniform is quantal emission at different locations along terminals innervating a single muscle fiber, and 2) can differences in quantal emission acc...