RESUMO
Objective To study the effect of progesterone on tumor necrosis factor (TNF-α),interleukin-1β (IL-1β),nerve growth factor(NGF) and brain derived neurotrophic factor(BDNF) expression in the cortex and hippocampus tissue in newborn rats with hypoxic-ischemic brain damage (HIBD),and to discuss the protective molecular mechanism of progesterone on HIBD in neonatal rats.Methods Forty-eight 7-day-old neonatal rats were randomly divided into 3 groups:sham-operated group,hypoxic-ischemic group and pretreatment group.Rats in hypoxic-ischemic group and pretreatment group were subjected to left common carotid artery ligation,then they were exposed to 80 mL/L oxygen and 920 mL/L nitrogen gas in the closed container at 37 ℃ for up to 2.5 h to establish HIBD models.Progesterone was injected intraperitoneally into the rats in the pretreatment group 30 min before hypoxia,and solution was injected into the first 2 groups.All the rats were killed at the 24 h after operation.The levels of TNF-α,IL-1β,NGF,BDNF were measured by enzyme linked immunosorbent assay and the expressions of TNF-α,IL-13,NGF,BDNF mRNA were analyzed by reverse transcription-polymerase chain reaction.Results The contents of TNF-α,IL-1β,NGF,BDNF and their mRNA expressions in hypoxic-ischemic group were significantly higher than those in the sham-operated group.In pretreatment groups,the levels of TNF-α,IL-1β and their mRNA expressions were significantly lower than those in hypoxic-ischemic group.The levels of NGF,BDNF and their mRNA expressions in pretreatment group were significantly higher than those in hypoxic-ischemic group (all P ＜ 0.05).Conclusions Progesterone exerts neuroprotective effect on hypoxic-ischemic encephalopathy-induced brain damage,and the action mechanism is related to down-regulate the expression of damage factor and up-regulate the expression of anti damage factor.