Abstract |
There are no reports on the effect of 7-nitroindazole (7-NI) on chemically-induced convulsions. Hence, in the present study, its (100 and 200 mg/kg) action was tested alone and in combination with phenobarbitone (20 mg/kg) and diazepam (0.25 mg/kg) on picrotoxin (PCT)-induced convulsions in rats. The changes produced by 7-NI on nitric oxide synthase (NOS) activity and nitric oxide (NO) concentration were determined in the brain. The effect of 7-NI was tested in L-arginine (1000 mg/kg) pretreated (30 min) animals. The smaller dose (100 mg/kg) of 7-NI did not alter NOS activity and NO concentration, but inhibited PCT-induced convulsions indicating that its anticonvulsant action was devoid of an involvement of NO. But, an inhibition of NOS activity, by a larger (200 mg/kg) dose of it, resulted in a promotion of the convulsant action of PCT and in an impairment of the anticonvulsant effect of both phenobarbitone and diazepam. The proconvulsant action of 7-NI was reverted by L-arginine. These results suggest that 100 and 200 mg/kg of 7-NI produce distinguishable action on PCT-induced convulsions because NOS activity is inhibited by 200 mg/kg and not by 100 mg/kg of it. The results further suggest that NO acts as anticonvulsant and that the NOS inhibitors, like 7-NI, cannot be used as an anticonvulsant either alone or in combination with other anticonvulsants.
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Authors | Vanaja Paul, P Ekambaram |
Journal | Indian journal of physiology and pharmacology
(Indian J Physiol Pharmacol)
Vol. 47
Issue 4
Pg. 400-6
(Oct 2003)
ISSN: 0019-5499 [Print] India |
PMID | 15266951
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Indazoles
- Picrotoxin
- Diazepam
- 7-nitroindazole
- Phenobarbital
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Topics |
- Animals
- Diazepam
(therapeutic use)
- Dose-Response Relationship, Drug
- Drug Therapy, Combination
- Indazoles
(adverse effects, therapeutic use)
- Male
- Phenobarbital
(therapeutic use)
- Picrotoxin
(toxicity)
- Rats
- Rats, Wistar
- Seizures
(chemically induced, prevention & control)
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