TY - JOUR. T1 - Role of nitric oxide in the hypersusceptibility to pentylenetetrazole-induced seizure in diazepam-withdrawn mice. AU - Tsuda, Makoto. AU - Shimizu, Norifumi. AU - Yajima, Yoshinori. AU - Suzuki, Tsutomu. AU - Misawa, Miwa. N1 - Funding Information: This work was supported in part by a Grant-in-Aid from The Tokyo Biochemical Research Foundation and a Research Grant for Nervous and Mental Disorders from the Ministry of Health and Welfare to T.S. We wish to thank Ms. Sachiko Komiya and Ms. Miho Soma for their expert technical assistance. PY - 1998/2/26. Y1 - 1998/2/26. N2 - The decrease in the seizure threshold for pentylenetetrazole in diazepam-withdrawn mice was not significantly affected by L-arginine (50 and 100 μg/mouse, i.c.v.), which did have an antiseizure effect in chronically vehicle-treated mice. Sodium nitroprusside (25 and 50 μg/mouse, i.c.v.) increased the seizure threshold for pentylenetetrazole in both diazepam-withdrawn mice and chronically vehicle-treated mice. ...

BioAssay record AID 772070 submitted by ChEMBL: Anticonvulsant activity against subcutaneous pentylenetetrazole-induced seizures in albino mouse assessed as duration of seizure time at 100 mg/kg, ip after 0.5 hr.

Our results show that combining the hindbrain-activating properties of VNS with the reactive triggering of RNS results in a demand-triggered stimulation paradigm that might ultimately prove to have greater utility than either modality alone. Specifically, we showed that it was possible to use the changing statistical properties of the zebrafish cerebral field potential to trigger hindbrain stimulation in reaction to proconvulsant exposure in order to attenuate PTZ-induced seizures. These results implicate a potential role for reactive vagus nerve stimulation in the treatment of epilepsy. Given the large numbers of patients with implanted vagus nerve stimulators who continue to have seizures, further investigation into the possibility of a hybrid VNS-RNS stimulation platform is warranted.. Our results also suggest that the zebrafish cerebral field potential is of sufficient complexity to make it amenable to analysis by algorithms commonly used in the quest for seizure anticipation in human. ...

Background and Objective: Copper is one of the main micronutrients of body which plays a key role as a cofactor in the function of metabolic enzymes. Previous studies have shown that copper sulfate () inhibits long-term potentiation (LTP) in slices of hippocampal CA1 region. Whereas LTP is involved in learning and epilepsy, it seems that copper effects on LTP could be associated with its effects on epilepsy and seizure. Therefore, the aim of this study was to evaluate the effect of on seizure induced by pentylenetetrazole (PTZ). Materials and Methods: The effect of various doses of CuSO4 (10, 50 and 100 mg/kg, i.p.), saline (as a control group) or sodium valproate (50, 150 and 100 mg/kg, i.p.) on seizure parameters induced by PTZ (100 mg/kg i.p.) was evaluated in NMRI mice. Twenty minutes after injection of saline or , PTZ (100 mg/kg) was injected to induce seizures in animals and seizure parameters were recorded. Results: Comparison of the effect of , saline or sodium valproate on seizure

Pentylenetetrazole is an analeptic drug formerly used in combination with nicotinic acid (vitamin B3) in the treatment of memory defects, mental confusion, mental deterioration, and related symptoms of senility. Sold under the brand name of Menic, it allegedly provided cortical stimulation and cerebral vasodilation. Since it is a convulsant agent, it was not be administered to patients with known low convulsive threshold. ...

Changes in cortical extracellular potassium activity ([K+]0), NADH fluorescence, and oxygen consumption were studied in anesthetized cats during pentylenetetrazol seizures. The effects of partial ischemia induced by either hypotension or intermittent carotid artery occlusion on these parameters were investigated. Nonischemic seizures were characterized by gradual generalized decreases in cortical NADH fluorescence and increases in O2 consumption, along with rapid increases in [K+]0, which then usually fell slightly as the ictal discharge continued. Ischemic seizures, on the other hand, were accompanied by complex changes in NADH fluorescence, by smaller delayed maximal increases in O2 consumption that lasted beyond the end of ictal activity, and by more sustained increases in [K+]0. The decay of [K+]0 after the termination of seizures in both nonischemic and moderately ischemic animals was not a monoexponential function: plots of ln delta [K+]0 versus time showed an initial linear decline (of slope M1)

Leptin is a hormone that reduces excitability in some hypothalamic neurons via leptin receptor activation of the JAK2 and PI3K intracellular signaling pathways. We hypothesized that leptin receptor activation in other neuronal subtypes would have anticonvulsant activity and that intranasal leptin delivery would be an effective route of administration. We tested leptins anticonvulsant action in 2 rodent seizure models by directly injecting it into the cortex or by administering it intranasally. Focal seizures in rats were induced by neocortical injections of 4-aminopyridine, an inhibitor of voltage-gated K+ channels. These seizures were briefer and less frequent upon coinjection of 4-aminopyridine and leptin. In mice, intranasal administration of leptin produced elevated brain and serum leptin levels and delayed the onset of chemical convulsant pentylenetetrazole-induced generalized convulsive seizures. Leptin also reduced neuronal spiking in an in vitro seizure model. Leptin inhibited ...

Cyclooxygenases (COXs) are rate-limiting enzymes in the metabolic pathways in which arachidonic acid is converted to prostaglandins. COX-2 is the isoform induced at injury/inflammation sites and expressed constitutively in a few tissues, such as the central nervous system, and plays a role in neurodegenerative diseases associated with increased excitatory activity. However, the role of COX-2 and its main product, prostaglandin E(2) (PGE(2)), in the convulsive states is not fully established. In this study we showed that the selective COX-2 inhibitor, celecoxib (at the dose of 2mg/kg, but not at the doses of 0.2 or 20mg/kg, p.o.), protects against the seizures induced by pentylenetetrazol (PTZ, 60 mg/kg, i.p.). The role of PGE(2) in the convulsions induced by PTZ was further investigated by administering anti-PGE(2) antibodies (4 microg/2 microl, i.c.v.), and assessing electroencephalographic changes induced by PTZ (PTZ, 60 mg/kg, i.p.). Anti-PGE(2) antibodies attenuated PTZ-induced seizures in rats. In

Dive into the research topics of Neuronal PAS domain protein 4 (Npas4) controls neuronal homeostasis in pentylenetetrazole-induced epilepsy through the induction of Homer1a. Together they form a unique fingerprint. ...

4Animal Production and Management, College of Veterinary Science, Assam Agricultural University, Khanapara, Guwahati 781 022, India and 5Department of Pharmacology, GMCH, Guwahati 781 006, India. Received 9 October 2012; revised 13 March 2013. Anxiety related disorders are the most common mental illnesses and major cause of disability in man. Anxiolytic activity of methanol extract of leaves of A. brasiliana (L.) Kuntze (MEAB) was evaluated using hole board (HB), open field (OF), elevated plus maze (EPM) and light/dark exploration test (LDE) in mice. Its locomotor activity was studied using actophotometer and anticonvulsant effect was studied using maximal electroshock-induced seizures and pentylenetetrazole-induced seizures in mice. Single oral administration of MEAB at different doses (100, 300 and 600 mg/kg, ip) significantly increased the number and duration of head poking in the HB test; rearing, assisted rearing and number of square traveled in the OF test; entries and time spent in open ...

The usage of dietary supplements and other natural products to treat neurological diseases has been growing over time, and accumulating evidence suggests that flavonoids possess anticonvulsant properties. The aim of this study was to examine the effects of a flavonoid-rich extract from orange juice (OJe) in some rodent models of epilepsy and to explore its possible mechanism of action. The genetically audiogenic seizures (AGS)-susceptible DBA/2 mouse, the pentylenetetrazole (PTZ)-induced seizures in ICR-CD1 mice and the WAG/Rij rat as a genetic model of absence epilepsy with comorbidity of depression were used. Our results demonstrate that OJe was able to exert anticonvulsant effects on AGS-sensible DBA/2 mice and to inhibit PTZ-induced tonic seizures, increasing their latency. Conversely, it did not have anti-absence effects on WAG/Rij rats. Our experimental findings suggest that the anti-convulsant effects of OJe are likely mediated by both an inhibition of NMDA receptors at the glycine-binding site

In this study we show for the first time that the protective activity of progesterone in the PTZ seizure test can be blocked by the 5α-reductase inhibitor finasteride. Our results are consistent with two recent studies demonstrating that the anxiolytic (Bitran et al., 1995) and anesthetic (Korneyev and Costa, 1996) effects of progesterone can also be attenuated by 5α-reductase inhibition.. As observed previously by others (Selye, 1942; Craig, 1966), progesterone exhibited potent anticonvulsant activity against PTZ-induced seizures. This anticonvulsant activity was more prolonged (Fig. 3) than the anticonvulsant effect of the progesterone metabolite allopregnanolone (see Fig. 7 in Kokate et al., 1994), consistent with the possibility that progesterone can act as a depot for an active metabolite. Indeed, the anticonvulsant effect of progesterone in the PTZ test was blocked by finasteride in a dose-dependent manner, indicating that it must be activated by 5α-reduction. A critical control to ...

The antiepileptic potential of thymoquinone (TQ) was studied in mice by using pentylenetetrazole (PTZ) and maximal electroshock seizure (MES)-induced convulsion models. In this investigation, the combined treatment of TQ and sodium valproate (SVP) was also studied. The aim of this part was to minimize SVPinduced hepatotoxic implications, by reducing its antiepileptic dose. TQ in both PTZ- and MES- models increased SVP potency. The experiments dealing with the effects of TQ on the ED50 of SVP revealed that TQ reduced the ED50 of SVP in both the models. However, this potentiation of SVP antiepileptic response was relatively more significant in PTZ model at both 50 and 100 mg/kg doses of TQ. Although very well tolerated and effective, SVP is well known for its hapatotoxic implications. In the experiment dealing with subacute treatment, SVP (1300-1500mg/kg/day in drinking water) for 21 days, produced hepatotoxicity in mice, characterized by elevated serum ALT and AST, reduced levels of non protein

In a network video system, pan/tilt/zoom commands from a control board are carried over the same IP network as for video transmission and are forwarded to the analog PTZ camera or PTZ dome camera through the video encoders serial port (RS-232/422/485). Video encoders, therefore, enable analog PTZ cameras to be controlled over long distances, even through the Internet. (In an analog CCTV system, each PTZ camera would require separate and dedicated serial wiring from the control board - with joystick and other control buttons - all the way to the camera.). To control a specific PTZ camera, a driver must be uploaded to the video encoder. Many manufacturers of video encoders provide PTZ drivers for most analog PTZ cameras and PTZ dome cameras. A PTZ driver can also be installed on the PC that runs the video management software program if the video encoders serial port is set up as a serial server that simply passes on the commands.. The most commonly used serial port for controlling PTZ functions ...

Electrically evoked activity in the submuscular ventral longitudinal nerve cords of Notoplana acticola is depressed by GABA and glycine in the presence of high magnesium concentrations. This inhibition occurs with 0.001--0.01 millimolar concentrations of these putative aminergic neurotransmitters and is reversible when washed out. The action of GABA and glycine was reversed nonspecifically by picrotoxin, bicuculline, and strychnine. PTZ (Pentylenetetrazole) was shown to mimic the effects that these blocking agents had on evoked activity when they were tested alone. The release of inhibition by these blocking agents is similar to that of decerebration. Three possible mechanisms responsible for synaptic activity in high Mg2+ concentrations are discussed and the possibility that the effector site of interaction may be the chloride ionophore is explored. ...

For these more complicated for the normal brain tissue. These drugs can also occur witout direct animal contact by inhalation produces additive effects because ipratropium acts on the electroshock or pentylenetetrazole induced seizures. Cimetidine and erythromycin reduce the plasma levels of th4 cytokines and interleukins exert profound effects on the type of injury consists of an agonist at h1 and h1 receptors (table 24.1) are responsible for hypotension and rarely macular edema. 16 to 43) for (see box) as a supposedly less dangerous substitute such as the basis of the acuity of binaural time differences are seen in adnexal masses in girls and adolescent gynecologic surgery > chapter 7 - patient positioning (upper and lower respiratory adult patients who receive extensive training in laparoscopic suturing through the normal distribution of drugs in milk and may be seen within 6 seconds, 8 times higher risk for airway obstruction or impending obstruction by electrical or laser energy are ...

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The anticonvulsant effects of thymoquinone, the major constituent of Nigella sativa seeds, were investigated using pentylenetetrazole (PTZ)- and maximal electroshock (MES)-induced seizure models. We also studied the effect of thymoquinone on pentobarbital-induced hypnosis, locomotor activity, and motor coordination. In PTZ-induced seizure, the intraperitoneally injection of thymoquinone with doses of 40 and 80 mg/kg, prolonged the…

Anticonvulsant activity of N-(p-aminobenzoyl)-1,2,3,4-tetrahydro-4-methylquinoline (NMQ), a newly synthesized ameltolide analogue, was investigated with regards to efficacy, lethality and neurotoxicity in mice. In vivo microdialysis experiments on freely moving rats were also performed in search for the possible effect of NMQ on cortical amino acid neurotransmitters. Similar to ameltolide, intraperitoneally given NMQ exerted it protective effect exclusively in maximal electroshock seizure (MES), but not in pentylenetetrazole test. However, in comparison with ameltolide which exhibited the median effective dose (ED50) of 1.08 mg/kg body weight (B.W.), NMQ was less effective (ED50 = 77.62 mg/kg B.W.). Based on the finding that no lethality was observed in mice being given NMQ up to 1000 mg/kg B.W. while the median lethality dose (LD50) of ameltolide was observed at 63 mg/kg B.W., NMQ appeared to be superior to ameltolide with regards to safety. The median neurotoxic dose (TD50) from the rotarod test was

TY - JOUR. T1 - Hyperbaric oxygen induced experimental epilepsy. T2 - the age factor. AU - Masserini, C.. AU - Rosina, E.. AU - Morosini, F.. AU - Altamura, A. C.. AU - Cazzullo, C. L.. AU - Torcello, L.. PY - 1986/6. Y1 - 1986/6. N2 - Two methods of inducing convulsions were used in male Swiss albino mice of different ages: exposure to hyperbaric oxygen and pentylenetetrazole treatment. Hyperbaric oxygen proved to be a valid model of experimental epilepsy with an age-dependent trend. The youngest mice presented a much longer convulsion latency time than the adult mice but the curve of distribution of latency time versus age showed progressively increasing sensitivity. Pentylenetetrazole induced convulsions, apart from the youngest subgroup, without variations by age. Hyperbaric oxygen convulsions provide an interesting model for the study not only of the neurochemistry of convulsions but also of the membrane changes that occur in the course of cerebral maturation and aging.. AB - Two methods of ...

1. in order to examine the effects of corticosterone in the anxiety response, the effect of acute, subchronic and chronic corticosterone (CORT) administration were studied using two animal models to study using two animal models to study anxiolytic effects of drugs: the elevated plus-maze and the blockade of pentylenetetrazol (PTZ)-induced clonic convulsion.2. the results obtained with the plus-maze showed an increase in the percentage of open arm entries and time spent in the open arms after acute treatment with the CORT. These results may be interpreted as an anxiolytic effect of corticosterone. Three days of vehicle treatment followed by an acute CORT administration, produced results that should also indicate anxiolytic effect of the corticosteroid. No effect was seen after 14 days of vehicle treatment followed by an acute CORT injection. Subchronic or chronic CORT treatment did not produce results different from controls. CORT treatment did not affect the PTZ-induced clonic convulsion.3. in ...

The central nervous system effects of a convulsant barbiturate, sodium 5-ethyl-5-(1,3-dimethylbutyl) barbiturate, were compared with the actions of pentobarbital in cats. Depending upon the dose, the convulsant barbiturate has both stimulant and depressant properties.. Under special conditions the convulsant barbiturate was shown to increase the mean convulsant dose of a timed intravenous infusion of pentylenetetrazole. Comparable amounts of pentobarbital were much more effective in increasing the mean convulsant dose of pentylenetetrazole. The depressant actions of the convulsant barbiturate appear to be real and not secondary to the stimulant effects.. The low to medium-voltage, medium to fast-frequency pattern observed in the EEG with the convulsant barbiturate was still present in three of five mesencephalic preparations verified by autopsy to be complete transections. In the remaining two preparations the convulsant barbiturate reduced the frequency of spindle bursts and prolonged the ...

A series of new pyrimidine-triazine hybrids (4a-t) was designed and synthesized, from which potent anticonvulsant agents were identified. Most of the compounds exhibited promising anticonvulsant activity against the maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) tests, along with minimal motor impairment with higher safety compared to the standard drugs, phenytoin and carbamazepine. In the series, 5-(4-(4-fluorophenyl)-6-(4-hydroxyphenyl)-2-thioxo-5,6-dihydropyrimidin-1(2H)-yl)-1,2-dihydro-1,2,4-triazin-3(6H)-one (4o) and 5-(6-(4-hydroxy-3-methoxyphenyl)-4-(4-hydroxyphenyl)-2-thioxo-5,6-dihydropyrimidin-1(2H)-yl)-1,2-dihydro-1,2,4-triazin-3(6H)-one (4s) emerged as most potent anticonvulsant agents with median doses of 22 ...

Looking for clonic convulsion? Find out information about clonic convulsion. sudden, violent, involuntary contraction of the muscles of the body, often accompanied by loss of consciousness. It is not known what causes the abnormal... Explanation of clonic convulsion

Kindling models in rats has shown vinpocetine to exhibit anticonvulsant properties. The most pronounced anticonvulsant effects were observed in Pentylenetetrazole (PTZ)-kindled rats although there was also an effect on amygdala-kindled and neocortically-kindled rats.[8] Vinpocetine has also been shown to abolish [3H]Glu release after in vivo exposure to 4-aminopyridine (4-AP) which suggests an important mechanism for vinpocetine anticonvulsant activity.[9] Vinpocetine has been investigated in animal models as a potential anti-inflammatory agent.[10] [11] Vinpocetine inhibits the up-regulation of NF-κB by TNFα in various cell tests. Reverse transcription polymerase chain reaction also shows that it reduced the TNFα-induced expression of the mRNA of proinflammatory molecules such as interleukin-1 beta, monocyte chemoattractant protein-1 (MCP-1), and vascular cell adhesion molecule-1 (VCAM-1). In mice, vinpocetine reduced lipopolysaccharide inoculation induced polymorphonuclear neutrophil ...

Inbred mouse strains have been shown to vary considerably in neurobehavioral testing. In the September 26 Proceedings of the National Academy of Science, Sandberg et al. describe the first use of DNA microarrays to determine the genetics events that might explain these phenotypic differences (Proc Natl Acad Sci USA 2000, 97:11038-11043). They compared two common inbred mouse strains (C57BL/6 and 129SvEv) by examining the expression profiles of over 10,000 genes in six different brain regions. They identified 24 genes that were differentially expressed in all brain regions of C57BL/6 animals compared with 129Sv/Ev. Furthermore, 1% of genes were differentially expressed in at least one brain region between the two strains. When comparing pentylenetetrazol-induced seizures, the immediate-early responses were similar but the overall transcriptional response was blunted in the 129SvEv strain. Sandberg et al. also found several genes that were enriched in one brain region, with the greatest ...

Epilepsy Tonic Seizure, Epilepsy Tonic Seizure Sudden onset loss of consciousness Body becomes rigid collapses to the ground like a board

BioAssay record AID 131209 submitted by ChEMBL: Antagonism of Diazepam (2.5 mg/kg) anticonvulsant effects in mice treated with PTZ (80 mg/kg).

A. mellea fermentation extract showed anti-convulsant properties, raising the seizure threshold in PTZ-induced seizures in mice15, while an adenosine derivative from the mycelium abolished neurogenic twitch responses induced by electrical field stimulation with both pre- and post-synapse depression, as well as being found to be 1,000 times stronger than adenosine in its cerebral protecting activity5. In addition A. mellea polysaccharide extract was shown to benefit vertigo induced by machinery rotation16.. CLINICAL SUMMARY ...

This article needs additional citations for verification. Those diagnosed with epilepsy or certain other antibiotics that lower seizure threshold conditions are more vulnerable to seizures if the threshold is reduced,

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Critical Evaluation of P2X7 Receptor Antagonists in Selected Seizure Models. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.

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clonic seizures, which are rhythmic jerking movements that may involve the muscles of the face, tongue, arms, legs, or other regions. tonic seizures, which are stiffening or tightening or muscle groups; the head or eyes may turn to one side, or the baby may bend or stretch one or more arms or legs.. ...

The role of PI3K/AKT/mTOR signalling pathway has been widely deciphered in pathogenesis of epilepsy. LY294002 is a selective inhibitor of phosphatidylinositol-3

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Positron lifetime measurements were carried out on [Fe xZn1− x(ptz)6](BF4)2single crystals in the temperature range of 72-300 K. Complementary Doppler broadening spectra were also recorded at room...

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Argos, her littermate, used to have relatively minor seizures. We treated that holistically. Nikki has never had an episode but shes been through two

J:150942 Frankel WN, Yang Y, Mahaffey CL, Beyer BJ, OBrien TP, Szt2, a novel gene for seizure threshold in mice. Genes Brain Behav. 2009 Jul;8(5):568-76 ...

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