Neuroprotective effects of chronic estradiol benzoate treatment on hippocampal cell loss induced by status epilepticus in the female rat.

Neuroprotective properties of estrogen are supported by extensive experimental evidence. In this study, the effects of estrogen were examined on the neurodegeneration secondary to status epilepticus induced by kainic acid in the rat. Chronic supplementation of ovariectomized rats with estradiol benzoate (20 microg/day) did not modify the expression of seizures monitored by electroencephalography, but significantly reduced cellular loss in the hippocampus. This neuroprotection was in particular observed in the dentate hilus and CA3 pyramidal layer when treatment with estradiol benzoate was started five days before status epilepticus induction. These findings suggest that estrogen can exert neuroprotective effects in a model of status epilepticus, in the absence of anti-epileptic properties.