Expression Of Nerve Growth Factor And Tyrosine Kinase Receptor A In The Brain Of IUGR Fetal Rats

ObjectiveIntrauterine growth retardation(IUGR) aslo be called foetus growth restriction, mean that foetus birth weight less than 2500 g,or lower than the foetus of the same gestational age and the same homogeneity, the neonate birth weight of IUGR lower than 2 standard deviation of the neonate birth weight of normal neonate,or lower than the 10 percentile of normal body weight of the normal foetus. IUGR is the high risk of neural development dysplastic,to cause the functional disturbance of neurobiology, recognition and remembrance. The mean morbidity of IUGR is (6.39-16.3)% in our country, IUGR is severe complication of obstetrics and the significance cause of ambofacient death, the case fatality rate of IUGR is the 8 times of the normal foetus. Nerve growth factor(NGF) is one of the most important biogical activity molecules in the nerve system. Nerve growth factor(NGF) secretary by a lot of cells,is a kind of polypeptide,the important of effect of NGF are the survival of cell, cell differentiation, maturate,and the whole life time of neve cell. NGF can affect the high affinity recepter of tyrosine kinase A, to promote the differentiate of neuronal, the survivalte of neuronal, the form of synapse and improve the capability of remembrance and learning.To explore the mechanism of brain development retardation of IUGR fetal rats, and to analyze the expression of nerve growth factor and tyrosine kinase receptor A in the brain of IUGR fetal rats.Methods1.The experimental annimals were employed from the experimental animal center of China Medical Univercity,8-10 weekes old, Wistar mouse. The experimental annimals were feed with lower protein diet in the time of pregnancy,use the method of low-protein diet to set up IUGR experimental animal model,the control group feed with normal diet..The judgement guide of IUGR is the neonate birth weight of IUGR lower than 2 standard deviation of the neonate birth weight of normal neonate.2.Randomly divided experimental annimals into 0 day,7day,14day,21day group,to measure the weight of body and brain of experimental annimals.3. Hematoxylin and eosin stain was performed to examine the characteristic of the neonate brian, Nissl's staining was performed to examine to the change of Nissl body.4. Immunohistochemistry was performed to examine the change of the expression of NGF and TrkA.5.Western blot was performed to examine the change of the protein expression of NGF and TrkA.Results1.The IUGR incidence rate of the group of low-protein diet was 55.77%, were significantly higher than control group(P<0.05).2.The still birth rate of the group of low-protein diet was 23.08%, were significantly higher than control group(P<0.05).3.The body weight were significantly lower than control group(P<0.05)in the 0 day time.4. The brain weight were significantly lower than control group(P<0.05) in the 0,7,14,21 day time.5.The levels of NGF and TrkA in brain of fetal rats with IUGR were significantly lower than control group(P<0.05)in the 0,7,14,21 time.Conclusions1.Low-protein diet is good experimental annimals model,stable and reliable.2. The decrease of brain weight of IUGR with Low-protein diet may be continue correspondently long time.3. The decrease of protein levels of NGF and TrkA may be continue correspondently long time.