Seizure severity after kainic acid injections. Histograms show hourly seizure severity for 5 h after a single intraperitoneal injection of kainic acid in five rats (indicated by black, gray, white, diagonally hatched and vertically hatched lines, respectively). Clinical seizure severity scoring ranging from “0” for normal animals and “7” for death are detailed in the text. Note, animal death from seizures occurred at 4 and 5 h.