Extracellular application of tetraethylammonium (TEA) has been shown to elicit a prolonged synaptic potentiation in the CA1 region of the hippocampus that is unaffected by NMDA receptor antagonists, but is blocked by antagonists to voltage-dependent calcium channels (Aniksztejn and Ben-Ari, 1991; Huang and Malenka, 1993). In the present study the relation between TEA-induced potentiation and NM...

Neocortical layer 5 pyramidal neurons possess long apical dendrites that receive a significant portion of the neurons excitatory synaptic input. Passive neuronal models indicate that the time course of excitatory postsynaptic potentials (EPSPs) generated in the apical dendrite will be prolonged as they propagate toward the soma. EPSP propagation may, however, be influenced by the recruitment of...

Dendritic integration of excitatory and inhibitory inputs is critical for neuronal computation, but the underlying rules remain to be elucidated. Based on realistic modeling and experiments in rat hippocampal slices, we derived a simple arithmetic rule for spatial summation of concurrent excitatory glutamatergic inputs (E) and inhibitory GABAergic inputs (I). The somatic response can be well ap...

The second order somatosensory thalamic nucleus (posteromedial nucleus, PoM) receives excitatory projection from layer VI of somatosensory cortex. While it is known that layer VI cortical input to first order, ventrobasal nucleus (VB) is modulated by cholinergic projections from the brainstem, no such data exists concerning the PoM nucleus. In order to study if layer VI corticothalamic transmis...

Experimental evidence supports a number of mechanisms for the synaptic change that occurs with long-term potentiation (LTP) including insertion of AMPA receptors, an increase in AMPA receptor single channel conductance, unmasking silent synapses, and increases in vesicle release probability. Here we combine experimental and modeling studies to quantify the magnitude of the change needed at the ...

Spinal lamina I projection neurones that transmit nociceptive information to the brain play a pivotal role in hyperalgesia in various animal models of inflammatory and neuropathic pain. Consistently, activity-dependent long-term potentiation can be induced at synapses between primary afferent C-fibres and lamina I projection neurones but not unidentified neurones in lamina I. The specific prope...

KEY POINTS Regular-spiking interneurons in the hippocampal stratum oriens exhibit a form of long-term potentiation of excitatory transmission that is independent of NMDA receptors but requires co-activation of Ca2+ -permeable AMPA receptors and group I metabotropic glutamate receptors. We show that T-type Ca2+ channels are present in such interneurons. Blockade of T-type currents prevents the i...

The effect of acute intrahippocampal infusion of brain-derived neurotrophic factor (BDNF) on synaptic transmission in the dentate gyrus was investigated in urethan-anesthetized rats. Medial perforant path-evoked field potentials were recorded in the dentate hilus and BDNF-containing buffer was infused (4 microl, 25 min) immediately above the dentate molecular layer. BDNF led to a slowly develop...

It has been demonstrated that stimulation of protein kinase A (PKA) results in enhanced synaptic transmission in the hippocampus and other brain areas. To investigate mechanisms of the PKA-mediated potentiation of synaptic transmission, we used rat hippocampal embryonic cultures. In low-density cultures, paired recordings under the perforated patch demonstrated that 15-min forskolin treatment p...

Introduction: Previous studies indicate that exercise influences cognitive function. Nevertheless, considering that exercise in animal study can be voluntary, or forced, effects of exercise (specially forced exercise) on learning and memory abides as a matter of controversy. The present study aimed to investigate the effects of treadmill exercise on LTP in the dentate gyrus of rats. Methods: T...