Estrogen effects on pilocarpine-induced temporal lobe epilepsy in rats

ObjetiveTo evaluate the effects of conjugated equine estrogens (CEE) on the pilocarpine-induced epilepsy in rats.Study design40 female rats were divided into: GPC (positive control) presented “status epilepticus” (SE) induced by pilocarpine; GOC (ovariectomized control) only castrated; GNC (negative control) received only saline solution; GPE received pilocarpine, presented SE, castrated and received 50 μg/kg CEE treatment; GPV received pilocarpine, castrated and received propylene glycol (vehicle). The animals were monitored by a video system. At the end of observation, the brains removed for later histologic analysis using Neo-Timm and Nissl methods.ResultsThe GPE presented a reduction in number of seizures compared to GPV. The Neo-Timm analysis showed that GPV had greater sprouting of mossy fibers, with a denser band in the area of the dentate gyrus hilum compared to GPE. On Nissl staining, GPE showed evident neuronal loss in the CA3 area. GPV presented loss in CA1 and dentate gyrus.ConclusionEstrogen may have a protecting effect on the central nervous system.