Abstract：OBJECTIVE: To study the mechanism of brain development delay in rats with intrauterine growth retardation (IUGR) by examining the expression of nerve growth factor (NGF) and tyrosine kinase receptor A (Trk A) in the brain. METHODS: Thirty-two pregnant rats were randomly fed with a normal diet (control group) or lower protein diet (IUGR group) during pregnancy (n=16 each). The pup rats were sacrificed at 0, 7, 14 or 21 days after birth. The protein levels of NGF and TrkA in the brain were determined by Western blot and immunohistochemistry staining. RESULTS: The levels of NGF and TrkA in the brain in pup rats of the IUGR group were significantly lower than those in the control group 0, 7, 14 and 21 days after birth. CONCLUSIONS: The decreased expression of protein levels of NGF and TrkA in the brain might be one of the causes of brain development delay in IUGR rats.
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