Anticonvulsant effects of eliprodil alone or combined with the glycineB receptor antagonist L-701,324 or the competitive NMDA antagonist CGP 40116 in the amygdala kindling model in rats

1999 ◽  
Vol 38 (2) ◽  
pp. 243-251 ◽  
Author(s):  
Piotr Wlaź ◽  
Ulrich Ebert ◽  
Wolfgang Löscher
Keyword(s):  
Receptor Antagonist ◽  
Nmda Antagonist ◽  
Kindling Model ◽  
Amygdala Kindling ◽  
Cgp 40116 ◽  
Anticonvulsant Effects

scholarly journals Antiepileptogenic and Anticonvulsant Effects of YM90K, a Selective AMPA-Receptor Antagonist, in the Rat Kindling Model of Epilepsy

Epilepsia ◽  
1998 ◽  
Vol 39 (S5) ◽  
pp. 74-75
Author(s):  
Masazumi Kodama ◽  
Yoshihiro Kitamura ◽  
Fumihiko Koyama ◽  
Toshiki Sato ◽  
Keiko Sato ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Ampa Receptor ◽  
Kindling Model ◽  
Ampa Receptor Antagonist ◽  
Anticonvulsant Effects

scholarly journals Effect of ramosetron, a 5-HT3 receptor antagonist on the severity of seizures and memory impairment in electrical amygdala kindled rats

2022 ◽  
Vol 72 (1) ◽  
Author(s):  
Zeynab Sayahi ◽  
Alireza Komaki ◽  
Masoud Saidi Jam ◽  
Seyed Asaad Karimi ◽  
Safoura Raoufi ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Memory Impairment ◽  
Kindling Model ◽  
Serotonergic Receptors ◽  
Anticonvulsive Effect ◽  
Y Maze ◽  
Stage 4 ◽  
Male Wistar Rats ◽  
Amygdala Kindling ◽  
Induced Changes

AbstractThe entorhinal cortex (EC) plays a pivotal role in epileptogenesis and seizures. EC expresses high density of serotonergic receptors, especially 5-HT3 receptors. Cognitive impairment is common among people with epilepsy. The present study investigated the role of 5-HT3 receptor on the severity of seizures and learning and memory impairment by electrical kindling of amygdala in rats. The amygdala kindling was conducted in a chronic kindling manner in male Wistar rats. In fully kindled animals, ramosetron (as a potent and selective 5-HT3 receptor antagonist) was microinjected unilaterally (ad doses of 1, 10 or 100 µg/0.5 µl) into the EC 5 min before the novel object recognition (NOR) and Y-maze tests or kindling stimulations. Applying ramosetron at the concentration of 100 μg/0.5 µl (but not at 1 and 10 µg/0.5 µl) reduced afterdischarge (AD) duration and increased stage 4 latency in the kindled rats. Moreover, the obtained data from the NOR test showed that treatment by ramosetron (10 and 100 µg/0.5 µl) increased the discrimination index in the fully kindled animals. Microinjection of ramosetron (10 and 100 µg/0.5 µl) in fully kindled animals reversed the kindling induced changes in the percentage of spontaneous alternation in Y-maze task. The findings demonstrated an anticonvulsant role for a selective 5-HT3 receptor antagonist microinjected into the EC, therefore, suggesting an excitatory role for the EC 5-HT3 receptors in the amygdala kindling model of epilepsy. This anticonvulsive effect was accompanied with a restoring effect on cognitive behavior in NOR and Y-maze tests.

Antiepileptogenic and anticonvulsant effects of NBQX, a selective AMPA receptor antagonist, in the rat kindling model of epilepsy

1994 ◽  
Vol 638 (1-2) ◽  
pp. 36-44 ◽  
Author(s):  
Tazuko Namba ◽  
Kiyoshi Morimoto ◽  
Keiko Sato ◽  
Norihito Yamada ◽  
Shigetoshi Kuroda
Keyword(s):  
Receptor Antagonist ◽  
Ampa Receptor ◽  
Kindling Model ◽  
Ampa Receptor Antagonist ◽  
Anticonvulsant Effects

Anticonvulsive and anti-epileptogenesis effects of Echinacea purpurea root extract, an involvement of CB2 receptor

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Masoumeh Gholami ◽  
Jamal Amri ◽  
Saeed Pazhoohan ◽  
Mehdi Sadegh
Keyword(s):  
Mortality Rate ◽  
Receptor Antagonist ◽  
Wistar Rats ◽  
Echinacea Purpurea ◽  
Root Extract ◽  
Cb2 Receptor ◽  
Kindling Model ◽  
Male Wistar Rats ◽  
Clonic Seizures ◽  
Cb2 Receptors

Abstract Objective Phytocannabinoids beyond the Δ9-tetrahy-drocannabinol have shown anticonvulsive effects. Also, alkylamides from Echinacea purpurea have been proved as cannabinomimetics. We examined the effect of the hydroalcoholic root extract of E. purpurea on pentylenetetrazol (PTZ)-induced tonic–clonic seizures and kindling model of epileptogenesis and the involvement of CB2 receptors as the mediator of this effect. Methods Male Wistar rats (200 ± 20 g) were used. Single intraperitoneal (i.p.) injection of PTZ (80 mg/kg) was used to induce tonic–clonic seizures. The kindling model of epileptogenesis was induced by daily injections of PTZ (37 mg/kg; i.p. for 15 days). Latency and duration of the stages were monitored for analysis. The hydroalcoholic root extract of E. purpurea was injected (i.p.) 20 min before seizure induction at the doses of 10, 50, 100 and 200 mg/kg. CB2 receptor antagonist SR144528 was injected (0.1 mg/kg; i.p.) 20 min before the Echinacea injection. Results In the tonic–clonic model, pretreatment with E. purpurea at the doses of 100 and 200 mg/kg significantly increased latencies to S2–S6, while it significantly decreased S6 duration and mortality rate. SR144528 injection before the injection of 100 mg/kg of E. purpurea significantly prevented the effects of the extract on S4–S6 latencies. In the kindling model, E. purpurea at the doses of 100 and 200 mg/kg significantly delayed epileptogenesis and decreased mortality rate, while SR144528 injection before the injection of 100 mg/kg of E. purpurea significantly blocked this effect of the extract. Conclusion These findings revealed the anticonvulsive and antiepileptogenesis effects of the E. purpurea root extract, which can be mediated by CB2 receptors.

Acute unilateral ureteral distension inhibits glutamate-dependent spinal pelvic-urethra reflex potentiation via GABAergic neurotransmission in anesthetized rats

2007 ◽  
Vol 292 (3) ◽  
pp. F1007-F1015 ◽  
Author(s):  
Kuo-Jung Chen ◽  
Hsien-Yu Peng ◽  
Chen-Li Cheng ◽  
Cheng-Hsu Chen ◽  
Jiuan-Miaw Liao ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Nmda Antagonist ◽  
Spinal Reflex ◽  
Reflex Response ◽  
External Urethral Sphincter ◽  
Gabaergic Neurotransmission ◽  
Single Action ◽  
Test Stimulation ◽  
Anesthetized Rats ◽  
Spike Number

The effects of an acute increase in intraureteral pressure (IUP) on pelvic-urethra reflex potentiation were examined in urethane-anesthetized rats by recording the external urethral sphincter electromyogram activities evoked by the pelvic afferent stimulation. Compared with a single action potential elicited by the test stimulation (TS; characterized by an intensity that evoked a constant reflex response without facilitation, 1/30 Hz, 1.03 ± 0.12 spikes/stimulation, n = 7), the repetitive stimulation [RS; identical stimulation intensity as the TS (1 Hz)] significantly induced spinal reflex potentiation (SRP; 16.90 ± 2.00 spikes/stimulation, P < 0.01, n = 7). Such SRP was significantly attenuated by intrathecal 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo (F) quinoxaline [NBQX; a glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionat (AMPA) receptor antagonist] and d-2-amino-5-phosphonovalerate [APV; a glutamatergic N-methyl-d-aspartate (NMDA) antagonist; the spike number per stimulation: 11.0 ± 0.70 for NBQX, 1.01 ± 0.30 for APV, and 16.90 ± 2.0 for RS, respectively, n = 7, P < 0.01]. Acute stepwise elevations of IUP gradually attenuated and eventually abolished the RS-induced SRP (16.80 ± 1.30, 17.00 ± 1.30, 16.30 ± 1.30, 10.50 ± 1.80, 8.80 ± 1.90, 3.50 ± 1.60, 0.80 ± 0.20, 0.70 ± 0.20, and 0.20 ± 0.10 spikes/stimulation at intraureteral pressure of 0, 2.5, 5, 7.5, 10, 12.5, 15, 17.5, and 20 cmH2O, respectively, n = 7). Intrathecal NMDA (a glutamatergic NMDA receptor agonist) and bicuculline (a GABA receptor antagonist) both reversed the abolition of RS-induced SRP caused by unilateral ureteral distension (14.0 ± 4.04 and 8.00 ± 1.53 spikes/stimulation, respectively, n = 7, P < 0.01). All the results suggested unilateral ureteral distension might compensatorily relax the urethra via GABAergic inhibition of NMDA-dependent SRP.

Excitatory transmission in the basolateral amygdala

1991 ◽  
Vol 66 (3) ◽  
pp. 986-998 ◽  
Author(s):  
D. G. Rainnie ◽  
E. K. Asprodini ◽  
P. Shinnick-Gallagher
Keyword(s):  
Nmda Receptor ◽  
Receptor Antagonist ◽  
Nmda Antagonist ◽  
Receptor Activation ◽  
Nmda Receptor Antagonist ◽  
Current Injection ◽  
Membrane Hyperpolarization ◽  
Postsynaptic Potentials ◽  
The Mean ◽  
Stimulation Of

1. Intracellular current-clamp recordings obtained from neurons of the basolateral nucleus of the amygdala (BLA) were used to characterize postsynaptic potentials elicited through stimulation of the stria terminalis (ST) or the lateral amygdala (LA). The contribution of glutamatergic receptor subtypes to excitatory postsynaptic potentials (EPSPs) were analyzed by the use of the non N-methyl-D-aspartate (non-NMDA) antagonist, 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX), and the NMDA antagonist, (DL)-2-amino-5-phosphonovaleric acid (APV). 2. Basic membrane properties of BLA neurons determined from membrane responses to transient current injection showed that at the mean resting membrane potential (RMP; -67.2 mV) the input resistance (RN) and time constant for membrane charging (tau) were near maximal, and that both values were reduced with membrane hyperpolarization, suggesting an intrinsic regulation of synaptic efficacy. 3. Responses to stimulation of the ST or LA consisted of an EPSP followed by either a fast inhibitory postsynaptic potential (f-IPSP) only, or by a fast- and subsequent slow-IPSP (s-IPSP). The EPSP was graded in nature, increasing in amplitude with increased stimulus intensity, and with membrane hyperpolarization after DC current injection. Spontaneous EPSPs were also observed either as discrete events or as EPSP/IPSP waveforms. 4. In physiological Mg2+ concentrations (1.2 mM), at the mean RMP, the EPSP consisted of dual, fast and slow, glutamatergic components. The fast-EPSP (f-EPSP) possessed characteristics of kainate/quisqualate receptor activation, namely, the EPSP increased in amplitude with membrane hyperpolarization, was insensitive to the NMDA receptor antagonist, APV (50 microM), and was blocked by the non-NMDA receptor antagonist, CNQX (10 microM). In contrast, the slow-EPSP (s-EPSP) decreased in amplitude with membrane hyperpolarization, was insensitive to CNQX (10 microM), and was blocked by APV (50 microM), indicating mediation by NMDA receptor activation. 5. In the presence of CNQX (10 microM), ST stimulation evoked an APV-sensitive s-EPSP. In contrast, LA stimulation evoked a f-IPSP, which when blocked by subsequent addition of bicuculline methiodide (BMI; 30 microM) revealed a temporally overlapping APV-sensitive s-EPSP. These data suggest that EPSP amplitude and duration are determined, in part, by the shunting of membrane conductance caused by a concomitant IPSP. 6. Superfusion of either CNQX or APV in BLA neurons caused membrane hyperpolarization and blockade of spontaneous EPSPs and IPSPs, suggesting that these compounds may act to block tonic excitatory amino acid (EAA) release within the nucleus, and that a degree of feed-forward inhibition occurs within the nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)

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