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1.
The methanolic extract of rhizomes of Cyperus articulatus, a plant used in traditional medicine in Africa and Latin America for many diseases, possesses anticonvulsant activity in mice. This extract protected mice against maximal electroshock (MES)- and pentylenetetrazol (PTZ)-induced seizures. It also delayed the onset of seizures induced by isonicotinic acid hydrazide and strongly antagonized N-methyl-D-aspartate-induced turning behavior. The ED(50) for protection against seizures was 306 (154-541) mg/kg intraperitoneally (i.p.) for the PTZ test and 1005 (797-1200) mg/kg i.p. for the MES test. The ED(50) of methanolic extract against N-methyl-D-aspartate-induced turning behavior was 875 (623-1123) mg/kg i.p. C. articulatus L. methanolic extract protected 54% of mice from seizures induced by strychnine at the dose of 1000 mg/kg i.p. but had no or a moderate effect only against picrotoxin- or bicuculline-induced seizures. With these effects, the rhizome of C. articulatus L. possesses anticonvulsant properties in animals that might explain its use as a traditional medicine for epilepsy in Africa.  相似文献   

2.
AIM OF THE STUDY: To investigate the anticonvulsant activity of root bark extract of Carissa edulis. MATERIALS AND METHODS: The median lethal dose (LD(50)) of Carissa edulis extract was determined using Lork's method (1983). The anticonvulsant activity of the extract was assessed in pentylenetetrazole (PTZ)-induced convulsion in mice and maximal electroshock test (MEST) in chicks, with benzodiazepine and phenytoin as standard drugs, respectively. While mechanistic studies were conducted using both flumazenil, a GABA(A)-benzodiazepine receptor complex site antagonist and naloxone a non-specific opioid receptor antagonist. RESULTS: The median lethal dose (LD(50)) of Carissa edulis was 282.8mg/kg and over 5000mg/kg following intraperitoneal and oral administration, respectively. Carissa edulis produced 40% and 20% protection against convulsion at 5 and 20mg/kg, respectively, compared with 100% protection with benzodiazepine. The mean onset and percentage protection against convulsion in Carissa edulis extract-treated mice were reduced by flumazenil and naloxone. Carissa edulis exhibited dose-dependent inhibition of the convulsion induced by MEST with 20mg/kg providing 90% protection while phenytoin (20mg/kg) produced 100% protection. CONCLUSION: These results suggest that Carissa edulis possesses biologically active constituent(s) that have anticonvulsant activity which supports the ethnomedicinal claims of the use of the plant in the management of epilepsy.  相似文献   

3.

Aim of the study

To systematically investigate the anticonvulsant activity of methanol extract of Benkara malabarica roots and to provide a biochemical basis elucidating its mode of action.

Methods

The median lethal dose (LD50) of Benkara malabarica extract was determined. The anticonvulsant activity of the extract was assessed in strychnine-induced and isoniazide-induced convulsion models; phenytoin (20 mg/kg) and diazepam (1 mg/kg) were used as standards, respectively. Percentage protection provided by the drug was accounted as decrease in the number of convulsions within 8 h of observation. Mechanism of action was studied by performing GABA transaminase (GABA-T) assay, isolated from rat brain. Active constituent was isolated and characterized from the plant extract.

Results

The median lethal dose (LD50) of Benkara malabarica was found to be more than 500 mg/kg. It demonstrated 30% and 35% protection against strychnine-induced convulsions and 60% and 80% protection against isoniazide-induced convulsions, at doses of 25 mg/kg and 50 mg/kg, respectively. Enzyme assay results revealed that Benkara malabarica extract possesses GABA-T inhibitory activity (IC50 = 0.721 mg/ml). Scopoletin which was identified as the major constituent of the extract was found to be an inhibitor of GABA-T (IC50 = 10.57 μM).

Conclusions

The anticonvulsant activity of the plant extract is predominantly GABA mediated and may be due to the action of scopoletin alone or is a result of synergy of different compounds in the extract in which scopoletin is the major constituent.  相似文献   

4.
Anticonvulsant and neurotoxicity profile of Nardostachys jatamansi in rats   总被引:1,自引:0,他引:1  
Ethanol extract of the roots of Nardostachys jatamansi DC. (Valerianaceae) was studied for its anticonvulsant activity and neurotoxicity, alone and in combination with phenytoin in rats. The results demonstrated a significant increase in the seizure threshold by Nardostachys jatamansi root extract against maximal electroshock seizure (MES) model as indicated by a decrease in the extension/flexion (E/F) ratio. However, the extract was ineffective against pentylenetetrazole (PTZ)-induced seizures. Nardostachys jatamansi root extract also showed minimal neurotoxicity against rotarod test at doses that increased the seizure threshold. Further, pretreatment of rats with phenytoin at a dose of 12.5, 25, 50 and 75 mg/kg in combination with 50mg/kg of Nardostachys jatamansi root extract resulted in a significant increase in the protective index (PI) of phenytoin from 3.63 to 13.18. The dose response studies of phenytoin alone and in combination with Nardostachys jatamansi extract on the serum levels of phenytoin clearly demonstrated the synergistic action of both the drugs.  相似文献   

5.
Preliminary pharmacological studies were performed on the methanol extract of Bixa orellana L. (Bixaceae) leaves to investigate neuropharmacological, anticonvulsant, analgesic, antidiarrhoeal activity and effect on gastrointestinal motility. All studies were conducted in mice using doses of 125, 250 and 500 mg/kg of body weight. In the pentobarbitone-induced hypnosis test, the extract statistically reduced the time for the onset of sleep at 500 mg/kg dose and (dose-dependently) increased the total sleeping time at 250 and 500 mg/kg dose. A statistically significant decrease in locomotor activity was observed at all doses in the open-field and hole-cross tests. In the strychnine-induced anticonvulsant test, the extract increased the average survival time of the test animals (statistically significant at 250 and 500 mg/kg). The extract significantly and dose-dependently reduced the writhing reflex in the acetic acid-induced writhing test. Antidiarrhoeal activity was supported by a statistically significant decrease in the total number of stools (including wet stools) in castor oil-induced diarrhoea model. A statistically significant delay in the passage of charcoal meal was observed at 500 mg/kg in the gastrointestinal motility test. The extract was further evaluated in vitro for antioxidant and antibacterial activity. It revealed radical scavenging properties in the DPPH assay (IC(50)=22.36 microg/ml) and antibacterial activity against selected causative agents of diarrhoea and dysentery, including Shigella dysenteriae.  相似文献   

6.
Since a previous study indicated that the water extract of Scutellariae radix (SR) had high affinity for the benzodiazepine (BDZ) binding site of GABA(A) receptors, the present study examined whether SR water extract has an anticonvulsant effect in vivo and an enhancing effect on gamma-amino-n-butyric acid (GABA)-stimulated uptake of 36Cl(-) in cortex preparation in vitro in mice. The results showed that SR water extract had little effect on pentylenetetrazol (PTZ, 85 mg/kg, s.c.)-induced clonic seizures but significantly inhibited maximal electroshock-induced tonic seizures with an ED(50) of 3.6 g/kg. The BDZ agonist chlordiazepoxide (10 mg/kg, i.p.) had anticonvulsant activity on both types of seizures. In 36Cl(-) uptake assay, SR water extract (1-500 microg/ml) had no significant effect on 25 microM GABA-stimulated 36Cl(-) uptake, whereas chlordiazepoxide (10 microM) increased the 36Cl(-) uptake to 125% of control. Therefore, the present results showed for the first time that SR water extract had anticonvulsant activity against maximal electroshock-induced tonic seizures, and suggested that this anticonvulsant effect might be not via the activation of the BDZ binding site of GABA(A) receptors, but probably via the prevention of seizure spread.  相似文献   

7.
Fresh leaves of Baphia nitida supplied by a herbalist were extracted, screened phytochemically and then subjected to various pharmacological tests. The phytochemical tests showed the presence of saponin, flavonoid glycosides and true tannins. In the dose range used, no acute toxicity was observed for the ethanolic extract. The extract showed a dose dependent antinociceptive (analgesic) activity in mice with the analgesic activity of 500 mg/kg extract being comparable to that of 300 mg/kg of acetylsalicylic acid. The extract demonstrated an antidiarrhoeal effect by protecting rats against castor oil induced diarrhoea. This was also dose related but less than the protection afforded by sodium salicylate. The extract did not demonstrate any appreciable anticonvulsant effect against strychnine-induced convulsion in rats.  相似文献   

8.
The present study was undertaken to investigate the putative activity of a methanol extract of Hypericum montbretti (Guttiferae) on the central nervous system. Rutin (1519 ppm) and quercitrin (784 ppm) were identified as the major phenolic compounds in the extract. When administered at 25, 50 and 100 mg/kg doses, the extract decreased the total number of head‐dipping behaviours performed by mice during a hole‐board test. Administration of both the extract and diazepam (2 mg/kg) reduced spontaneous locomotory activity, potentiated hexobarbital (60 mg/kg)‐induced sleeping parameters and prevented pentylenetetrazole (80 mg/kg)‐induced seizures relative to the controls. These findings are the first to indicate the sedative and anticonvulsant activities of H. montbretti extract. Atropine (2 mg/kg) and naloxone (5 mg/kg) pre‐treatment did not reverse the sedative effect, indicating that muscarinic and opioidergic mechanisms did not contribute to the pharmacological action. However, pre‐treatment with flumazenil (a benzodiazepine receptor antagonist) reversed both the sedative and anticonvulsant effects induced by a 100 mg/kg dose of the extract, indicating the involvement of the GABA(A)‐benzodiazepine receptor complex. In conclusion, H. montbretti extract is a novel candidate as a sedative and anticonvulsant drug for the treatment of sleep disorders and for the prevention of epileptic seizures. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

9.

Ethnopharmacological relevance

To investigate the anticonvulsant activity of the leaf extract of Justicia extensa T. Anders used traditionally in the treatment of convulsion.

Materials and methods

The anticonvulsant activity of the methanolic extract of Justicia extensa (50, 100 and 200 mg/kg, p.o.) was assessed in strychnine-induced (STR) and picrotoxin-induced (PCT) convulsion models in mice. Diazepam (1 mg/kg) and phenobarbitone (2 mg/kg) were used as reference drugs respectively.

Results

The extract showed no toxicity and significantly prolonged (p < 0.01-0.05) the onset and reduced the duration of the seizures induced by picrotoxin (5 mg/kg, i.p.) in a dose dependent manner. Phenobarbitone completely inhibited the seizures in this model. Similarly, in the seizures induced by strychnine (1 mg/kg, i.p.), the extract also prolonged the onset and reduced the duration of the seizures though not in a dose dependent manner. Diazepam failed to inhibit the strychnine-induced seizures. The plant extract however showed a significantly higher anticonvulsant activity at 100 and 200 mg/kg in comparison with diazepam.

Conclusions

The results obtained from this work suggest that Justicia extensa has anticonvulsant activity and this supports the use of the plant traditionally in the treatment of convulsion.  相似文献   

10.
Anti-inflammatory and analgesic activities as well as the median lethal dose (LD50) of water-ethanolic extract (PHE) of the aerial parts of Pothomorphe umbellata were evaluated in animal models. The ED(50) (oral) for the inhibition of carrageenan-induced rat paw edema assay was determined to be 550 mg/kg, while the LD(50) was higher than 2.0 g/kg. At a dose of 550 mg/kg, PHE inhibited the inflammatory process by 48.7% (P < 0.05) on the third hour of the assay (edema peak) when compared to the untreated control. Indomethacin, the positive control used in this test, inhibited the edema by 58.6% at a dose of 10 mg/kg, when compared to the untreated control (P < 0.05). All three fractions--hexane, methylene chloride and ethyl acetate--obtained by partition of PHE with respective solvents also showed inhibition of the edema induced by carrageenan over a period of 4h but the methylene chloride fraction showed the best activity. The activity shown by the methylene chloride fraction at 200 mg/kg was comparable to that exhibited by indomethacin at a dose of 10mg/kg. The number of writhings induced by a 0.6% acetic acid solution intraperitoneal injection was decreased by 22% (P < 0.05) in the group treated orally with Pothomorphe umbellata crude extract. PHE also inhibited the granulomatous tissue formation in rats by 6.2% (P < 0.05). In the same assay, topically applied dexamethasone decreased the granuloma formation by 14.2%. The above results suggest that Pothomorphe umbellata crude extract has analgesic and anti-inflammatory properties supporting its folkloric use for the treatment of these conditions.  相似文献   

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