CONCORDANCE OF QUANTITATIVE DAMAGE WITHIN THE DIENCEPHALON AND TELENCEPHALON FOLLOWING SYSTEMIC PILOCARPINE (380 MG/KG) OR LITHIUM (3 MEQ/KG)/PILOCARPINE (30 MG/KG) INDUCED SEIZURES

We tested the hypothesis that a single systemic injection of 380 mg/kg of the muscarinic agonist pilocarpine would produce more diffuse and severe seizure-induced brain damage than a single injection of lithium (3 mEq/kg) followed 4 h later by < 1/10 the dosage of pilocarpine. The hypothesis was not supported; the pattern of quantitative brain damage 50-60 days after the seizures were elicited by either treatment was comparable within the limits of measurement error. Within the diencephalon and subcortical telencephalon the same structures were either damaged in a similar quantitative manner or were spared. Only five of the 119 damaged structures exhibited statistically significant treatment differences at P < 0.01. The results are compatible with the explanation that lithium may enhance the excitotoxic effects of subsequent muscarinic stimulation,