NMDA excitotoxicity has been proposed to mediate the death of retinal ganglion cells (RGCs) in glaucoma and ischemia. Here, we reexamine the effects of glutamate and NMDA on rat RGCs in vitro and in situ. We show that highly purified RGCs express NR1 and NR2 receptor subunits by Western blotting and immunostaining, and functional NMDA receptor channels by whole-cell patch-clamp recording. Never...

NMDA receptor-induced excitotoxicity has been hypothesized to mediate abnormal choline (Cho) metabolism that is involved in alterations in membrane permeability and cell death in certain neurodegenerative disorders. To determine whether NMDA receptor overactivation modulates choline metabolism in vivo, we investigated the effects of NMDA on interstitial choline concentrations using microdialysi...

Ginsenosides are low molecular weight glycosides found in ginseng that exhibit neuroprotective effects through inhibition of N-methyl-D-aspartic acid (NMDA) receptor channel activity. Ginsenosides, like other natural compounds, are metabolized by gastric juices and intestinal microorganisms to produce ginsenoside metabolites. However, little is known about how ginsenoside metabolites regulate N...

Neurons release nitric oxide (NO) in response to activation of receptors for the excitatory amino acid N-methyl-D-aspartate (NMDA). We examined the hypothesis that activation of receptors for NMDA produces dilatation of the cerebral microcirculation that is mediated by NO. Diameters of cerebral arterioles were measured using a closed cranial window in anesthetized rabbits. Under control conditi...

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a potentially fatal autoimmune syndrome in which IgG antibodies target the NR1 subunit of NMDA resulting profound dysregulation and neurotransmission.

Microinjection of NMDA and non-NMDA agonists into the same sites in pontomedullary motor "inhibitory" areas of decerebrate animals produced opposite effects on muscle tone. Microinjection of non-NMDA agonists into peri-locus coeruleus alpha (peri-LC alpha) and nucleus magnocellularis (NMC) suppressed muscle tone, while injection of NMDA agonists at the same sites increased muscle tone and produ...

L-Homocysteic acid (HCA), an endogenous excitatory amino acid in the mammalian CNS, potently activates N-methyl-D-aspartate (NMDA) receptors in hippocampal neurons. However, the responses to HCA in Purkinje cells, which lack functional NMDA receptors, have been largely unexplored: HCA may activate conventional non-NMDA receptors by its mixed agonistic action on both NMDA and non-NMDA receptors,...

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...