Ketamine: convulsant or anti-convulsant?
Ketamine hydrochloride in doses producing narcotic-cataleptic effects (50--100 mg/kg, IP) reduced the intensity of picrotoxin convulsions and eliminated seizures caused by metrazol administration. Subcataleptic doses (5--20 mg/kg) increased the duration of mitigated convulsive symptoms (abortive grand mal fits, jerks) especially those evoked by picrotoxin. Narcotic-cateleptic doses of ketamine considerably increased the duration of the period of single and multiple jerks produced by picrotoxin administration. Both convulsants transformed 1--2 Hz "ketamine complexes" into 2--4 Hz Wave spike discharges which appeared in a quasi-periodic fashion alternating with periods of relatively suppressed electrocortical activity. Electroencephalographic grand mal patterns were typically dissociated from behavioral manifestations under 50--100 mg/kg of ketamine, followed by a short period of postictal depression and a rapid recovery of preseizure electrographic patterns. Findings suggest that mechanisms involved in seizure alleviation may be responsible for sustaining mitigated convulsive phenomena. Neuro-chemical processes underlying antiepileptic ketamine potency remain unknown.
D000818:Animals; D000927:Anticonvulsants; D003292:Convulsants; D004347:Drug Interactions; D004569:Electroencephalography; D007649:Ketamine / Q000494:pharmacology*; D008297:Male; D010433:Pentylenetetrazole / Q000494:pharmacology; D010852:Picrotoxin / Q000494:pharmacology; D051381:Rats
D000927:Anticonvulsants; D003292:Convulsants; D007649:Ketamine; D010433:Pentylenetetrazole; D010852:Picrotoxin