Cocaine and seizure protection in mice of varying brain weights.

The effects of cocaine administration on seizure duration and proportion of animals that seized were examined in mice genetically selected for differential brain weight. In the two experiments reported, mice of the Fuller brain weight lines and of the Binghamton Heterogeneous stock were used. In Experiment 1, 21 day old male and female mice were administered either 0, 5, 10 or 20 mg/kg of cocaine hydrochloride. Fifteen minutes after each mouse was injected, a transcorneal shock was administered to that animal. Type and duration of seizure were measured. Low brain weight mice were more susceptible to seizures and showed more severe seizures than the medium and high brain weight mice or the Heterogeneous stock. Cocaine hydrochloride provided a degree of protection against seizures in a dose dependent fashion, particularly in the medium brain weight and Heterogeneous stock mice. Experiment 2 examined whether repeated daily doses of cocaine (15-21 days of age) would alter the pattern of susceptibility described above. In this experiment mice were given either 0 mg/kg or 10 mg/kg of cocaine hydrochloride. At 21 days of age, 15 minutes after injection, mice were subjected to transcorneal shock and the subsequent nature and duration of seizures observed. Mice of the low brain weight line were again seen to have more seizures than those from the high brain weight line. Cocaine decreased the severity of transcorneal induced seizures.