Seizure-like activity and cellular damage in rat hippocampal neurons in cell culture

Furshpan, E. J.; Potter, David

doi:10.1016/0896-6273(89)90033-0

Cited by 146 publications

(92 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, although acute treatment with NMDA receptor antagonists protects against toxicity, chronic pretreatment enhances toxicity. Consistent with our results, increases in calcium hyperexcitability and seizure-like activity have been reported after chronic glutamate receptor blockade of neuronal cultures (Furshpan and Potter, 1989;Obrietan and Van den Pol, 1995). The APV-induced increase in toxicity may be partially accounted for by the twofold increase in surface association of NR1, but it seems likely that the increased synaptic localization is important.…”

Section: Functional Implications Of Activity-regulated Synaptic Targesupporting

confidence: 81%

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

2001

View full text Add to dashboard Cite

Chronic activity blockade increases synaptic levels of NMDA receptor immunoreactivity in hippocampal neurons. We show here that blockade-induced synaptic NMDA receptors are functional and mediate enhanced excitotoxicity in response to synaptically released glutamate. Activity blockade increased the cell surface association of NMDA receptors. Blockade-induced synaptic targeting of NMDA receptors did not require protein synthesis but required phosphorylation and specifically cAMPdependent protein kinase (PKA). Furthermore, activation of PKA was sufficient to induce synaptic targeting of NMDA receptors regardless of receptor activity status. These results implicate PKA activity downstream of receptor blockade as a mediator of enhanced synaptic transport or stabilization of NMDA receptors. Synaptic clustering of NR1-green fluorescent protein was observed in living neurons in response to NMDA receptor and cAMP phosphodiesterase antagonists and occurred gradually over the course of a day. This pathway represents a cellular mechanism for synaptic homeostasis and is likely to function in metaplasticity, long-term regulation of the ability of a synapse to undergo potentiation or depression. Key words: NMDA receptor; synaptogenesis; activity; synaptic clustering; excitotoxicity; subcellular localization; hippocampus; NR1-GFPThe NMDA-type glutamate receptor plays a central role in circuit development, memory formation, and many forms of synaptic plasticity in the mammalian brain. The NMDA receptor is composed of the essential NR1 subunit and one or more of the modulatory NR2A-D and NR3 subunits (Nakanishi, 1992;Seeburg, 1993;Mori and Mishina, 1995). NMDA receptor channel opening requires ligand binding (by presynaptic glutamate release) and removal of Mg 2ϩ block (by postsynaptic depolarization), thus conferring on the NMDA receptor the ability to function as a molecular coincidence detector (Mayer et al., 1984). Through its Ca 2ϩ permeability, NMDA receptor function is linked with many downstream signal transducing pathways in the neuron. The magnitude and kinetics of calcium elevation at the synapse are thought to be major determinants of long-term effects on synaptic efficacy (Lisman, 1989;Abraham and Bear, 1996).The level of NMDA receptor function at the synapse critically regulates brain function and cell survival. Mice expressing 5% of normal levels of NR1 exhibit increased motor activity, stereotypy, and deficits in social and sexual interactions, behaviors associated with schizophrenia (Mohn et al., 1999). Deletion of NR1 targeted postnatally selectively to CA1 of the hippocampus results in mice that are viable but deficient in spatial learning and formation of temporal memory (Tsien et al., 1996;Huerta et al., 2000). In contrast, overactivation of NMDA receptors contributes substantially to neuronal death during epilepsy, stroke, trauma, and neurodegenerative disorders (McDonald and Johnston, 1990;Choi, 1994;Rothman and Olney, 1995;During et al., 2000).NMDA receptor function is regulated during development and by ...

show abstract

Section: Functional Implications Of Activity-regulated Synaptic Targesupporting

confidence: 81%

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

2001

View full text Add to dashboard Cite

show abstract

“…The hippocampi were obtained from I-day-old Spra gue-Dawley rat pups and maintained by a method modi fied from Furshpan and Potter (1989). Hippocampal sec tions were then incubated in dissociation medium con taining papain (10 U/ml) and cysteine (3 mmol/L) for two 20-min periods.…”

Section: Hippocampal Neuronal Culturesmentioning

confidence: 99%

Neuroprotection by Peptide Growth Factors against Anoxia and Nitric Oxide Toxicity Requires Modulation of Protein Kinase C

Maiese

Boccone

1995

J Cereb Blood Flow Metab

View full text Add to dashboard Cite

Summary: Basic fibroblast growth factor (bFGF) and epi dermal growth factor (EGF) are neuroprotective during anoxia and nitric oxide (NO) toxicity. Signal transduction systems that modulate protein kinase C (PKC) also can modulate the toxic effects of anoxia and NO. We there fore examined whether PKC was involved in the protec tive effects of bFGF and EGF during anoxia and NO toxicity. Down-regulation or inhibition of PKC activity before anoxia or NO exposure prevented hippocampal neuronal degeneration. Yet, this protective effect of inhi bition of PKC activity was not present with the coadmin istration of growth factors. Combined inhibition of PKC activity and application of bFGF or EGF lessened the protective mechanisms of the growth factors. In addition, the protective ability of the growth factors was lost during anoxia and NO exposure with the activation of PKC, Peptide growth factors are increasingly being linked to the neurodegenerative effects of cerebral ischemia. In animal models, increased expression of basic fibroblast growth factor (bFGF) has been documented during both focal (Kumon et aI., 1993) and global (Takami et aI., 1992) models of cerebral ischemia. Administration of some trophic factors, such as insulin-like growth factor (Guan et aI., 1993) and transforming growth factor-Bl (Gross et aI., 1993), can reduce or limit the extent of cerebral

show abstract

“…Induction of neuronal hypere xcitabilit y. Dissociated hippocampal neurons grown with glutamate receptors and synapses chronically blocked (Ͼ14 d) by kynurenate (1 mM) and magnesium (10 mM MgC l 2 ) became hyperexcitable; when the kynurenate -Mg 2ϩ medium was replaced by a control salt solution without the blockers, neurons displayed seizure-like activity, consisting of bursts of action potentials riding on paroxysmal depolarization shifts (Furshpan and Potter, 1989).…”

Section: Methodsmentioning

confidence: 99%

“…Neurons cultured under conditions of chronic kynurenate blockade of glutamate receptors and chronic Mg 2ϩ blockade of synapses were hyperexcitable (Furshpan and Potter, 1989). After removal from chronic blockade, these neurons exhibited spontaneous action potential bursts, typically 300 -500 msec long, riding on a wave of depolarization reminiscent of the paroxysmal depolarization shifts seen in epileptic foci in vivo and in vitro (Fig.…”

Section: Gaba C Receptors Inhibit Hyperexcitable Hippocampal Neuronsmentioning

confidence: 99%

Suppression of Neuronal Hyperexcitability and Associated Delayed Neuronal Death by Adenoviral Expression of GABA_CReceptors

2001

View full text Add to dashboard Cite

The excessive neuronal excitation underlying several clinically important diseases is often treated with GABA allosteric modulators in an attempt to enhance inhibition. An alternative strategy would be to enhance directly the sensitivity of postsynaptic neurons to GABA. The GABA C receptor, normally found only in the retina, is more sensitive to GABA and demonstrates little desensitization compared with the GABA A receptor. We constructed an adenovirus vector that expressed cDNA for both the GABA C receptor 1 subunit and a green fluorescent protein (GFP) reporter and used it to transduce cultured hippocampal neurons. Transduced neurons were identified by fluorescence, double immunocytochemistry proved colocalization of the 1 protein and the reporter, Western blot verified the expected molecular masses, and electrophysiological and pharmacological properties confirmed the presence of functional GABA C receptors. 1 -GFP transduction resulted in an increased density of GABA A receptors as well as expression of novel GABA C receptors. This effect was not reproduced by addition of TTX or Mg 2ϩ to the culture medium to reduce action potentials or synaptic activity. In a model of neuronal hyperexcitability induced by chronic blockade of glutamate receptors, expression of GABA C receptors abolished the hyperactivity and the consequent delayed neuronal death. Adenovirus-mediated neuronal GABA C receptor engineering, via its dual mechanism of inhibition, may offer a way of inhibiting only those hyperexcitable neurons responsible for clinical problems, avoiding the generalized nervous system depression associated with pharmacological therapy.

show abstract

Seizure-like activity and cellular damage in rat hippocampal neurons in cell culture

Cited by 146 publications

References 48 publications

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

Neuroprotection by Peptide Growth Factors against Anoxia and Nitric Oxide Toxicity Requires Modulation of Protein Kinase C

Suppression of Neuronal Hyperexcitability and Associated Delayed Neuronal Death by Adenoviral Expression of GABA_CReceptors

Contact Info

Product

Resources

About

Seizure-like activity and cellular damage in rat hippocampal neurons in cell culture

Cited by 146 publications

References 48 publications

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

cAMP-Dependent Protein Kinase Mediates Activity-Regulated Synaptic Targeting of NMDA Receptors

Neuroprotection by Peptide Growth Factors against Anoxia and Nitric Oxide Toxicity Requires Modulation of Protein Kinase C

Suppression of Neuronal Hyperexcitability and Associated Delayed Neuronal Death by Adenoviral Expression of GABACReceptors

Contact Info

Product

Resources

About

Suppression of Neuronal Hyperexcitability and Associated Delayed Neuronal Death by Adenoviral Expression of GABA_CReceptors