introduction: the brain glutamate neurotransmitter system and its nmda receptors in the nucleus accumbens play an important role in the incidence of the phenomena of sensitivity and addiction. the present study examined the inhibitory effect of glutamate nmda receptors in the nucleus accumbens in response to chronic stress. methods: after the unilateral and bilateral cannula placement in the nu...

Chronic exposure to lead (Pb) affects neural functions in central nervous system (CNS) particularly the learning and memory. On the other hand, alteration of calcium level in the CNS results in activation of NOS. It has been shown that lead enters the neurons through calcium channels and displaces Ca2+ from calcium binding proteins such as calmodulin and troponin C thereby affecting calcium-med...

The neuronal Na+-activated K+ channel Slack (aka Slo2.2, KNa1.1, or Kcnt1) has been implicated in setting and maintaining the resting membrane potential defining excitability firing patterns, as well generation of slow afterhyperpolarization following bursts action potentials. activity increases significantly under conditions high intracellular Na+ levels, suggesting this may exert important pa...

Ca influx through NMDA receptors (NMDARs) triggers synaptic plasticity, gene transcription, and cytotoxicity, but little is known about the regulation of NMDA-Rs themselves. We used two-photon glutamate uncaging to activate NMDA-Rs on individual dendritic spines in rat CA1 neurons while we measured NMDAR currents at the soma and [Ca] changes in spines. Low-frequency uncaging trains induced Ca-d...

It has been suggested that NR2B-containing NMDA receptors have a selective tendency to promote pro-death signalling and synaptic depression, compared to the survival promoting, synapse potentiating properties of NR2A-containing NMDA receptors. A preferential localization of NR2A-containing NMDA receptors at the synapse in maturing neurons could thus explain differences in synaptic vs. extrasyna...

The nucleus accumbens (NAcc) may play a major role in opiate dependence, and central NMDA receptors are reported to influence opiate tolerance and dependence. Therefore, we investigated the effects of the selective mu-opioid receptor agonist [D-Ala2-N-Me-Phe4,Gly-ol5]-enkephalin (DAMGO) on membrane properties of rat NAcc neurons and on events mediated by NMDA and non-NMDA glutamate receptors, u...

Properties of glutamatergic synaptic transmission were investigated by simultaneously voltage-clamping a pair of connected bipolar cells and cells in the ganglion cell layer (GLCs) in the newt retinal slice preparation. Activation of the Ca2+ current in a single bipolar cell was essential for evoking the glutamatergic postsynaptic current in the GLC. Depolarization for as short as 15 msec activ...

Background Self-injurious behaviors (SIBs) are devastating traits in autism spectrum disorder (ASD). Although deficits in pain sensation might be one of the contributing factors underlying the development of SIBs, the mechanisms have yet to be addressed. Recently, the Shank2 synaptic protein has been considered to be a key component in ASD, and mutations of SHANK2 gene induce the dysfunction of...

N-Methyl-D-aspartate (NMDA) receptors are a principal subtype of excitatory ligand-gated ion channels with crucial roles in a variety of physiological and pathological processes in the mammalian central nervous system (CNS). In contrast to synaptic non-NMDA receptors that rapidly internalize, synaptic NMDA receptors have been shown to be rather static. However, recent accumulating evidence give...

The N-methyl-D-aspartate (NMDA) receptor has been implicated in activity-dependent synapse stabilization, but its role as a detector of correlated activity during development is debated. In the amphibian retinotectal system, synaptic sorting and stabilization occur throughout larval life, and map refinement is dependent on continuous NMDA receptor function. Moreover, tadpole tecta chronically t...