Emergence of spontaneous seizures during the year following lithium/pilocarpine-induced epilepsy and neuronal loss within the right temporal cortices.
Thirty days after the induction of seizures in 16 rats with lithium (3 mEq/kg) and pilocarpine (30 mg/kg), the numbers of episodes of motor seizures (rapid forelimb clonus) during daily 10-minute observational periods were recorded for 11 months. The proportions of neuronal loss were ranked using two methods by light microscopy for all structures between the posterior and anterior commissures. Amounts of damage within the dentate gyrus, hilus (CA4), and CA3 field were most strongly correlated with numbers of seizures per month about 6 months before the brains were removed. The strongest correlations occurred between the amounts of damage within the right temporal cortices, even after the variance associated with damage within the dentate gyrus had been removed, and the numbers of seizures during the last 2 months. These results may explain the greater proportion of spontaneous seizures that begin with left side forelimb clonus and suggest a particular sensitivity of the right side of the brain to either their initiation or their consequences.
Persinger
M A
MA
Behavioral Neuroscience Program, Laurentian University, Sudbury Ont., Canada, P3E 2C6. mpersinger@laurentian.ca
Dupont
M J
MJ
D000818:Animals; D002470:Cell Survival / Q000502:physiology; D004827:Epilepsy / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology; D007839:Functional Laterality; D008094:Lithium; D008297:Male; D009410:Nerve Degeneration / Q000139:chemically induced / Q000503:physiopathology; D009474:Neurons / Q000187:drug effects / Q000473:pathology*; D010862:Pilocarpine; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology*; D013702:Temporal Lobe / Q000473:pathology*; D013997:Time Factors
D010862:Pilocarpine; D008094:Lithium