Seizure susceptibility in intact and ovariectomized female rats treated with the convulsant pilocarpine.

Despite numerous neuroendocrinological studies of seizures, the influence of estrogen and progesterone on seizures and epilepsy remains unclear. This may be due to the fact that previous studies have not systematically compared distinct endocrine conditions and included all relevant controls. The goal of the present study was to conduct such a study using pilocarpine as chemoconvulsant.

Hippocampal excitability increases during the estrous cycle in the rat: a potential role for brain-derived neurotrophic factor.

To test the hypothesis that induction of BDNF may contribute to changes in hippocampal excitability occurring during the female reproductive cycle, we examined the distribution of BDNF immunoreactivity and changes in CA1 and CA3 electrophysiology across the estrous cycle in rats. Hippocampal BDNF immunoreactivity increased on the day of proestrus as well as on the following morning (estrus), relative to metestrus or ovariectomized animals. Changes in immunoreactivity were clearest in mossy fiber axons of dentate gyrus granule cells, which contain the highest concentration of BDNF.