Contribution of estrogen receptors alpha and beta in the brain response to traumatic brain injury.

Object: Although there is evidence that estradiol has neuroprotective effects after traumatic brain injury (TBI) in female rats, it is unclear which estrogen receptor (ER) subtype, ERα or ERβ, mediates this effect. The authors therefore examined the roles of the different ERs in this effect. Here the authors used the ERα selective agonist propyl pyrazole triol (PPT) and the ERβ selective agonist diarylpropionitrile (DPN) alone and in combination in female rats to investigate this question.

Differences in brain edema and intracranial pressure following traumatic brain injury across the estrous cycle: involvement of female sex steroid hormones.

It has been shown that sex steroid hormones have profound neuroprotective effects in experimental traumatic brain injury (TBI). Because the endogenous hormone levels are proven to differ with estrous cycle stage, we evaluated whether estrous cycle stage affects various outcomes following diffuse TBI. TBI was induced by Marmarou's method in normal cycling and in ovariectomized rats with physiologically relevant restoration of hormonal levels by hormone capsule implantation.