Effects of pentylenetetrazole-induced status epilepticus on behavior, emotional memory and learning in immature rats

Status epilepticus (SE) can be harmful to the developing brain. Our knowledge of the emotional and behavioral consequences of generalized SE in developing animals remains limited. Therefore, we investigated the short- and long-term effects of pentylenetetrazole (PTZ)-induced SE on emotional memory and learning and behavioral parameters in immature rats. SE was induced in 16- to 20-day-old rats (P16-P20) using intraperitoneal injections of PTZ (n = 21); control rats received saline (n = 10). All animals were tested using an elevated T-maze and open-field test 2, 14, 30, and 180 days after SE, to evaluate emotional memory and learning and behavior. Anxiety levels decreased 2 and 14 days after SE, and conditioned learning of PTZ-treated immature rats was better than that of the control rats. These results indicate that a decreased anxiety level facilitates conditioned learning. Behavioral changes are transient, and no emotional memory or learning deficits occur following PTZ-induced SE in immature rats. (c) 2005 Elsevier Inc. All rights reserved.