Effects of prenatal protein malnutrition on perforant path kindling in the rat

Rats born to dams fed either a 6% (malnourished) or 25% (control) casein diet during gestation were all fostered to lactating dams on the 25% casein diet 24 h after birth and were maintained on this diet throughout life following weaning. At 90-120 days of age electrographic and behavioral responses to electrical kindling of the medial perforant pathway were investigated in animals from both the straight 25% diet (designated 25%/25% for the pre- and postnatal periods) and the dietary rehabilitated (designated 6%/25% casein diet for the pre- and postnatal periods) groups. Animals of the dietary rehabilitated group (6%/25%) were found to: (1) require a significantly lower stimulus intensity to evoke afterdischarge activity in the ipsilateral dentate gyrus; (2) progress through the various behavioral stages of kindling in a markedly different manner from the 25%/25% group, and; (3) require significantly more daily kindling stimulations to attain the full motor convulsive stage indicative of the kindled state. These results indicate that dietary protein rehabilitation at birth is incapable of reversing or significantly ameliorating the effects of gestational protein deficiency on susceptibility to seizure activity and acquisition of the kindled state. These findings indicate that gestational protein deficiency results in long-lasting, if not permanent, changes in neuronal systems in the hippocampal formation which are involved in both the electrographic and behavioral correlates of the kindling process.