Anticonvulsant action of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline in immature rats: comparison with the effects on motor performance.
Anticonvulsant action of 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX), a competitive antagonist at non-N-methyl-D-aspartate receptors for excitatory amino acids, was studied in a model of cortical epileptic afterdischarges (ADs) in 12-, 18- and 25-day-old rat pups with implanted electrodes. Electrical stimulation of sensorimotor cortex was repeated four times with 20-min intervals, NBQX (in doses of 10, 30, 60 or 90 mg/kg i.p.) or solvent (dimethyl sulfoxide, 1 ml/kg i.p.) were injected 10 min after the first afterdischarge. Dimethyl sulfoxide did not change the phenomena recorded; NBQX shortened ADs or at least blocked progressive prolongation observed under control conditions. Intensity of movements accompanying stimulation decreased after NBQX, and clonic movements accompanying ADs were suppressed in a dose-dependent manner. The highest dose of NBQX disabled the animals; therefore, the action of this drug on motor skills was studied in another group of animals. Even the dose of 30 mg/kg NBQX interfered with motor performance in 12- and 18-day-old rat pups, 25-day-old rat pups were more resistant to this action. NBQX exhibited only moderate antiepileptic action (suppression of progressive lengthening of ADs) at doses where unwanted side effects were absent.
Mares
P
P
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague.
Mikulecká
A
A
Pometlová
M
M
D000818:Animals; D000831:Animals, Newborn; D000927:Anticonvulsants / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D011810:Quinoxalines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013647:Task Performance and Analysis
D000927:Anticonvulsants; D011810:Quinoxalines; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline