Recent findings on neuroprotection against excitotoxicity in the hippocampus of female rats.

Newborn mammals are totally dependent on maternal milk and care for survival. The mother's brain undergoes different behavioural, physiological and emotional adaptations that make the mother more likely to satisfy the demands of the offspring. Recent reports from our group show that, compared to nulliparous rats, lactation diminishes cell damage induced by excitotoxicity in the dorsal hippocampus of the dam after systemic or i.c. administration of kainic acid (KA) and the resulting motor seizures. Elevated levels of prolactin (PRL), oxytocin, progesterone and glucocorticoids are characteristics of lactation, and the pronounced fluctuation of these hormones occurring in this phase may play a role protecting the hippocampus. Indeed, PRL administration to ovariectomised rats significantly diminishes the deleterious effects of KA in the dorsal hippocampus and reduces the progression of KA-induced seizures. Thus, lactation is a natural model for neuroprotection because it effectively prevents acute and chronic cell damage of the hippocampus induced by excitotoxicity.