Prenatal protein malnutrition and hippocampal function: rapid kindling.

A stimulation paradigm evoking rapidly recurring seizure activity from the hippocampal dentate gyrus was used to examine perforant path kindling in prenatally protein malnourished adult rats. Biphasic electrical stimulations (50 Hz) of five s duration were applied to the perforant path every five min for one hour over five consecutive days. Behavioral manifestations of seizure activity were assessed using the standard 0-5 scale. Prenatally malnourished rats exhibited significantly fewer convulsive seizures (stage 5) and required significantly more stimulations to attain the first stage 5 seizure than controls. Animals of the malnourished group also exhibited significantly more stage 1 seizures than control animals, indicating a significant retardation in the kindling rate of these animals. Additionally, 3 of the 11 malnourished animals failed to exhibit a single stage 5 seizure during the 60 stimulation test period. These findings parallel previous results reported for prenatally protein malnourished rats using the traditional one stimulation-per-day kindling paradigm and indicate that this rapid kindling paradigm can be effectively used to study the impact of various insults on seizure susceptibility and development in a shortened time frame.