Expression Of Follistatin、Activin A And BMP-4in Rats With Hypoxic-ischemic Brain Damage

ObjectiveTo investigate the expression and significance of follistatin,activin A andBMP-4in normal brain tissues of rats and the brain tissues with hypoxic andischemic in cortex and hippocampus.Comprehensive the mechanism betweenFollistatin,ActicinA and BMP-4,Find the signal intersection and provideexperimental basis for nerve reconstruction.Methods60SD pregnancy rats were divided into normal group and model group foreach30,according to the development of fetal rats in each group were randomlydivided into embryonic stage8.5days,13days,18days,3days,7days and30daysafter the birth of six subgroups(namely E8.5group,E13group,E18group,P3group,P7group,P30group of six subgroups).Used the different methodsrespectively to establish the hypoxic-ischemic model between the enbryomicand after the birth period.Expressions of Follistatin ActivinA and Bonemorphogenetic protein4were determined by immunohistochemical methodsbetween normal and model group in the different stages.Through the PT-PCRmethod,to detectied the expression of FS,ACTA and BMP-4between normaland model group in different periods. ResultsBy hematoxylin and eosin staining method we found that the brain nerronalnescrosis,some nuclei stained karyopyknosis,the number of neurons werereduced,nerve fibers were disorganized were loosed sligthly, necrosis ofneurons and the phenomenon of a few neurons were liked in acute ischemicchanges after hypoxic-ischemic damage. We found that Neurological deficitscores were increased and nerve injury were daggravated with the growth of theage by nerve function testing(P<0.01).The immunohistochemical method showthat the expression of FS and ACT A gradually reduced gradually with thenormal group and model group rats in development period of rats’cortex andhippocampus (P<0.01), there is almost no expression of BMP-4in embryonicperiod,the expression was low after the birth30days (P<0.01).We used Rt-PCRmethod to detect the expression of FS,ACT and BMP-4in model group werehigher than normal group (P<0.01), especially the expression of FS and ACT Aincreased significantly,the expression of hippocampus were increased obviouslythan cortex.ConclusionThe hypoxic-ischemic model was manufactured successfully.Theexpression of FS ACT A and BMP-4are closely related to developmental age,the expression of FS and ACT A were gradually decreased by the growth of age,While the expression of BMP-4was gradually in adulthood.Thehypoxic-ischemic injury can induce the high expression of FS ACT A andBMP-4,they were a protective material.Particularly,FS and ACT A was the earliest protective material.But the expression of BMP-4were lower than FSand ACT A.we speculated that the main function of FS was as the inhibitor ofACT A instead of the ligland of BMP-4to regulate neural development.