Objective:To observe the effects of radix astragali on hypertrophic scars in rabbit ears. Methods:Twenty healthy adult Japanese big ear rabbits were given hypertrophic scars over the ventral surface of the ears and on the 21st day after wound

animals were randomly divided into the treated groups (groups A

B

and C were treated with radix astragali in different concentrations)and the control groups(groups D and E were treated with saline and blank control

respectively). On the 32nd and 43rd day after wound

the thickness and hardness of scar were measured.The TGF-β1mRNA were detected in hypertrophic scar samples with RT- PCR.The change of scar tissues was observed with H&E staining and immunohistochemical staining with TGF-β1. Results:The thickness and hardness of scar were inversely correlated with the concentration of radix astragali in the radix astragali-treated group(P<0.05).Image analysis demonstrated that the expression of TGF-β1mRNA and its protein in all radix astragali-treated groups were significantly reduced as compared withthose in saline group and blank control group;There was significant difference in treated groups(P<0.05)

but no significant difference in control groups (P>0.05)between the 32nd day and43rd day groups.Conclusion:Radix astragali could inhibit proliferation of hypertrophic scars in the rabbit ears by decreasing the expression of TGF-β1mRNA and its protein. Thereby radix astragali may have beneficial effects in the treatment of hypertrophic scar.