ABSTRACT
Previous studies have demonstrated estrogen and progesterone decrease brain edema induced by TBI. The aim of the present study was to determine the effect of female sex steroids on cytokines, and proinflammatory evaluation of the effects of cerebral edema of these hormones whether ovarian hormones decrease brain edema by change in concentrations of proinflammatory cytokines. In this experimental study, 98 ovariectomized female rats [except groups 1 and 2] were divided into groups of control, sham, vehicle, low does of estrogen [El], high dose of estrogen [E2], low dose of progesterone [PI] and high dose of progesterone [P2]. Vehicle and sexual steroid hormones were injected intraperitoneally at 0.5 h after Moderate and diffuse TBI induced by Marmarou method. Brain level of cytokines and ovarian hormones were measured 6 h after TBI by ELISA method. Both E2 and PI caused significant increase of 52.8% and 79.2% in brain level of IL-lp. P2 significantly decreased the levels of IL-6 and TNF-alpha by 45.9% and 72% respectively. TGF-beta level seem to be increased by El up to 3.37 times significantly. Level of beta-Estradiol increased 4.58 times in E2 group and progesterone increased 1.56 times in P2 group significantly. This results suggested that ovarian hormones increased brain IL-lp and TGF-P and decreased IL-6 and TNF-alpha, this may be one mechanism by which hormones reduce cerebral edema