A Study On Early Intervention And Expression Of Receptor TrkA In Neonatal Rats With Hypoxic-ischemic Brain Drain Damage In Uterus.

[Objective] To investigate effect and mechanism of early intervention on brain function of rats with hypoxic-ischemic brain damage(HIBD) in uterus .[Methods] A rat model of HIBD in uterus was established by ligating uterinehorn vessel of pregnant rats on one side and the HIBD rats were divided into two groups :HIBD intervention group and HIBD non- intervention group .Normal intervention group and normal non- intervention group rats were set up by without ligating uterinehorn vessel of pregnant rats on the other side . The intervention groups were received the early stimulation and enriched environment for 28 days. "Y"-maze and flash visual evoked potential(F-VEP) was used to evaluate the brain function of rats . The numbers of surviving neurons and immunoreactive neurons of receptor TrkA in the forehead cortex and hippocampus of four group rats were observed under high power microscope .It was examined the results by SPSS10.0 statistical software package proceeds.[Results] The learning ablities and the memory keeping percentages in the intervention groups were better than those in the non- intervention groups(P<0.01),and improvements in HIBD intervention group were obvious(P<0.05). the latencies of major wave P1 in F-VEP for the intervention groups showed significant decreases compared with the non- intervention groups(P<0.01) , and decreases in HIBD intervention group were more obvious(P<0.05). The numbers of surviving neurons in forehead cortex and hippocampusCA2,CA3 were more in the normal groups than in the HIBD groups(P<0.01), The HIBD intervention group increased obviously(P<0.05) .The numbers of neurons labelled with receptor TrkA in forehead cortex and hippocampusCA2,CA3 were more in the intervention groups than in the non- intervention groups(P<0.01), The increase is obvious in HIBD intervention group(P<0.05) .[Conclusion] Early intervention that is early stimulation and enriched environment can significantly improve brain function of rats with hypoxic-ischemia in uterus .The mechanism is related to the increase of surviving neurons and receptor TrkA expressed in forehead cortex and hippocampus CA2,CA3.