Effects of Astragalus on content and mRNA expression level of TNF-α and IL-1β in rats’ lungs after repeated exposure to +Gz

Objective: To study the effects for Astragalus（AST） on its protection of the rats from lung injure induced by the sustained high +Gz exposure,so as to offer the theory basis of exploiting the Chinese traditional medicine to improve the pilots’ acceleration endurance.Methods: Twenty male healthy Wistar rats were randomly divided into 4 groups（n=5）: control group for +10Gz and +15Gz,AST intervention group for +10Gz and +15Gz.For control group 0.9% saline were injected into celiac cavity by 10ml/kg,and the AST were injected in AST groups by 10 g/kg.After one hour,the rats were exposed to +10Gz and +15Gz.Profile of the centrifuge +Gz exposures was trapezoidal,+10Gz lasted for 90s,+15Gz group for 30s.The +Gz repeated for 3 times with 30 min interval.The blood samples,Bronchoalveolar Lavage Fluid（BALF） and lung tissue homogenate were collected 4h after the last centrifuge run.The concentrations of TNF-α and IL-1β in the serum and BALF and their mRNA expression levels in rat lungs were measured.Results: For the AST convention group,the concentrations of TNF-α and IL-1β in the serum and BALF and their mRNA expression levels in the rat lungs were significantly lower than those of controls.Conclusion: ASY injection can alleviate inflammation of rats’ lung after high +Gz exposure,which demonstrated AST could protect the rats from lung injure induced by the sustained high +Gz exposure.