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...

Dopamine, via activation of D1 receptors, enhances N-methyl-d-aspartate (NMDA) receptor-mediated responses in striatal medium-sized spiny neurons. However, the role of specific NMDA receptor subunits in this enhancement remains unknown. Here we used genetic and pharmacological tools to dissect the contribution of NR1 and NR2A/B subunits to NMDA responses and their modulation by dopamine recepto...

Among integrative neurons displaying long-term synaptic plasticity, adult Purkinje cells seemed to be an exception by lacking functional NMDA receptors (NMDA-Rs). Although numerous anatomical studies have shown both NR1 and NR2 NMDA-R subunits in adult Purkinje cells, patch-clamp studies failed to detect any NMDA currents. Using more recent pharmacological and immunodetection tools, we demonstr...

The N-methyla-aspartate R1 (NMDA Rl), NMDA R2A, and NMDA R2C subunits were expressed transiently in double or triple combinations in human embryonic kidney (HEK) 293 cells. The biochemical and pharmacological properties of the cloned receptors were compared with those of adult mouse forebrain and cerebellum. Under conditions established for maximal expression, cotransfection of the NMDARl and R...

Reactive oxygen species (ROS) and nitric oxide (NO) participate in NMDA receptor signaling. However, the source(s) of the ROS and their role in the increase in cerebral blood flow (CBF) induced by NMDA receptor activation have not been firmly established. NADPH oxidase generates ROS in neurons, but there is no direct evidence that this enzyme is present in neurons containing NMDA receptors, or ...

In the CNS, activation of N-methyl-D-aspartate receptor (NMDA-R) glycine binding sites is a prerequisite for activation of postsynaptic NMDA-Rs by the excitatory neurotransmitter glutamate. Here we provide electrophysiological evidence that the glycine binding sites of presynaptic NMDA-Rs regulate glutamate release in layer II/III pyramidal neurons of the rat visual cortex. Specifically, our re...