Neuroadaptations in the nucleus accumbens (NAc) are associated with the development of drug addiction. Plasticity in synaptic strength and intrinsic excitability of NAc medium spiny neurons (MSNs) play critical roles in addiction induced by different classes of abused drugs. However, it is unknown whether morphine exposure influences synaptic strength, intrinsic excitability or both in NAc. Her...

Synaptic cell adhesion molecules (CAMs) are known to play key roles in various aspects of synaptic structures and functions, including early differentiation, maintenance, and plasticity. We herein report the identification of a family of cell adhesion-like molecules termed SALM that interacts with the abundant postsynaptic density (PSD) protein PSD-95. SALM2, a SALM isoform, distributes to exci...

The early processes that lead to synaptic dysfunction during aging are not clearly understood. Dysregulation of alpha-amino-3-hydroxy-5-methylisoxazolepropionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptors may cause age-related cognitive decline. Using hippocampal slice cultures exhibiting lysosomal dysfunction, an early marker of brain aging that is linked to protein accumulation, we ...

Gamma-frequency oscillations are prominent during active network states in the hippocampus. An intrahippocampal gamma generator has been identified in the CA3 region. To better understand the synaptic mechanisms involved in gamma oscillogenesis, we recorded action potentials and synaptic currents in distinct types of anatomically identified CA3 neurons during carbachol-induced (20-25 microM) ga...

Introduction: The prostaglandin E2 (PGE2), a cyclooxygenase (COX) product, play critical roles in the synaptic plasticity. Therefore, long term use of COX inhibitors may impair the synaptic plasticity. Considering the wide clinical administration of aspirin and its unknown effects on information processing in the brain, the effect of aspirin and sodium salicylate on the short term synaptic p...

Many central neurons possess large acid-activated currents, yet their molecular identity is unknown. We found that eliminating the acid sensing ion channel (ASIC) abolished H(+)-gated currents in hippocampal neurons. Neuronal H(+)-gated currents and transient acidification are proposed to play a role in synaptic transmission. Investigating this possibility, we found ASIC in hippocampus, in syna...

The calyx of Held (CoH) synapse serves as a model system to analyze basic mechanisms of synaptic transmission. Astrocyte processes are part of the synaptic structure and contact both pre- and postsynaptic membranes. In the medial nucleus of the trapezoid body (MNTB), midline stimulation evoked a current response that was not mediated by glutamate receptors or glutamate uptake, despite the fact ...

We investigated the mechanisms underlying the modulation of transmitter release from bipolar cells. Three currents, measured under whole-cell patch clamp in the tiger salamander retinal slice, were used to identify the sites of modulation and to establish their pharmacological profile. (1) A light-elicited inhibitory current was measured in bipolar cells that could be blocked by picrotoxin. Thi...

Neural networks can be simulated exactly using event-driven strategies, in which the algorithm advances directly from one spike to the next spike. It applies to neuron models for which we have (1) an explicit expression for the evolution of the state variables between spikes and (2) an explicit test on the state variables that predicts whether and when a spike will be emitted. In a previous wor...

The amplitudes and kinetics of miniature excitatory synaptic currents (MESCs) in mammalian central neurons vary widely. It is unclear whether this variability occurs at each synapse or arises from differences among a heterogeneous population of synapses. Furthermore, it is not known how variability in these currents would affect their associated postsynaptic Ca2+ transients. To address these qu...