Influence of astragalus membranaceous in inhibiting the activity of nitric oxide synthase after acute brain injury / 中国组织工程研究

ABSTRACT

BACKGROUND: Astragalus membranaceus plays an important role in the adjustment of immunological function. Whether does it have protective effect on neuron in the intervention of acute craniocerebral injury and what is the pathway in effect?OBJECTIVE: To observe the effect of astragalus membranaceus on activity of nitric oxide synthetase after brain injury.DEDIGN Randomized controlled trial.SETTING: Neurosurgery institute of Lanzhou Military Area Command of Chinese PLA.MATERIALS This experiment was completed in the Laboratory of Neurosurgery Institute of Lanzhou Military Area Command of Chinese PLA. Fifty-four healthy SD rats were divided randomly into 3 groups brain injury group( n=24), astragalus membranaceus group( n = 24) and control group( n = 6). Injury and astragalus membranaceus groups were sampled at 4different time points(0.5 hour, 2 hours, 6 hours, and 24 hours) after injury,6 rats were sacrificed at each time point.METHODS: The brain injury and astragalus membranaceus groups were prepared by improved Feeney' s free falling method. Bone windows were opened for the control group, but no brain injury produced. After injury, rats in astragalus membranaceus group were immediately injected 200 mg/kg astragalus membranaceus intraperitoneally rat cerebral injury models were established and the nitric oxide synthetase concentration was tested at different time points.MAIN OUTCOME MEASURES: Activity of nitric oxide synthetase in the brain tissue of rats in each group.RESULTS: All 54 rats entered the final analysis. Nitric oxide synthetase activity in brain injury and astragalus membranaceus groups increased sharply contrasting with control group at 30 minute after injury [ (46.44 ± 13.45),(43.15 ± 12.43), (40. 46 ± 12. 85) nkat/L, P ＜0.05], reaching the peak at 2hours[ (67.49 ± 22.45), (64. 26 ± 19.78) nkat/L, P ＜ 0.01 ], starting to drop from6 hours [(63.46±24. 68), (52.91 ±21.36) nkat/L, P ＜0. 01], and getting to basic level at 24 hours[ (41.23 ± 12. 57), (40.92 ± 12. 25) nkat/L,P ＞ 0.05 ]. In the astragalus membranaceus treated group, nitric oxide synthetase activity dropped at 2 hours and 6 hours after injury contrasting with injury group( P ＜ 0. 05, P ＜ 0. 01 respectively).CONCLUSION: Nitric oxide synthetase activity increases in the injured brain tissue and astragalus membranaceus can protect injured neuron by inhibiting nitric oxide synthetase activity.