The Expression And Significance Of Erythropoietin And Its Receptor In Brain Of Newborn Rat Suffered Fetal Distress

BackgroundStudies show intrauterine hypoxia on the brain, kidneys, heart, electrolyte,gastrointestinal tract, metabolism, lungs, liver, retina caused varying degrees ofdamage. The most far-reaching influence and serious consequence is brain damage,directly related to survival rete and mortality of the newborns. Fetal distress is thecommon cause of perinatal mortality and neonatal neurological sequelae. Seeking anearly method of assessing the state of development of the nervous system is aroundthe corner. Study points out that erythropoietin (EPO) has protective effects on thenervous system in recent years. EPO may have significant value on prognosis.ObjectiveTo study the expression of erythropoietin (EPO) and its receptor (EPOR) in thebrain of newborn rats suffered fetal distress, explore the vaule of prediction of braindamage and search the best time window of treatment of hypoxic-ischemic braininjury by exogenous EPO.Methods(1) A model of fetal distress was prepared by ligating bilateral uterine arteries ofthe rats with full-term pregnancy for10minutes before cesarean sections. Thenewborn rats born by cesarean sections which were not subjected to uterine arteryligation were used as the control group.(2) To observe morphological changes inbrain tissue at different time points (0,2,6,12,24and48hrs,3and7days) of the neonatal rats in experimental group,to slice brain tissue of newborn rats in controlgroup at72hrs point as reference substance. Finally, to analyze the two groupscomparatively.(3) The expression levels of EPO mRNA and EPOR mRNA in thebrian of newborn rats were detected by reverse transcription polymerase chainreaction (RT-PCR).(4) The expression levels of EPO and EPOR in the brian ofnewborn rats were detected by western blot at0,2,6,12,24and48hrs, and3and7days after birth.(5) Serum EPO levels were measured using ELISA simultaneously.The experimental data were statistically by SPSS10.0software.ResultsThe expression of EPO protein and mRNA in brain tissues in the fetal distressgroup increased as compared with the control group2,6and12hrs after birth(P<0.05). The expression of EPOR protein and mRNA in brain tissues increased ascompared with the control group2,6,12,24and48hrs, and3days after birth(P<0.05). Serum EPO levels in the fetal distress group were significantly higher thanin the control group2hrs after birth (t=2.52, P=0.02).Conclusions(1) EPO and EPOR levels in the brain increase in newbron rats suffering fromfetal distress quickly after birth. EPOR is high expressed continually and has longerduration.(2) This provides a basis for treatment for neonatal brain damage induced byfetal distress by exogenous EPO.(3) The variation of EPO and EPOR levels has acertain significance on diagnosis and treatment for neonatal brain damage sufferedfetal distress.