Vulnerability of Developing Rat Brain to Electroconvulsive Seizures

Abstract

Seventy-four immature rats received one supramaximal electroconvulsive seizure per day for ten days. Compared to paired control littermates, animals subjected to seizures between days 2 and 11 of postnatal life had a reduction in brain weight (—14%, P<.01) and brain cell number (—15%, P<.01). Rats convulsed between days 9 and 18 of life underwent a reduction in brain weight (—8%, P<.01), brain protein, and brain RNA without fall in brain DNA, suggesting a reduction of cell size without change in cell number. The largely postmitotic brain of animals shocked later in life (days 19 to 28) showed no change in brain weight, cell number, or cell size. No focal histological abnormalities were found in any group. These data suggest that the immature rat brain is vulnerable to seizures that leave the brain of older animals undamaged.