Objective: To observe the effect of modified Sini San(MSNS) on the behavior and concentration of plasma adrenocorticotropic hormone(ACTH) and serum corticosterone(CORT) in adolescent rats with stress. Method: The 32 male Wistar SPF rats were randomly divided into normal group

model group

fluoxetine group(0.01 g·kg-1)

MSNS group(16.9 g·kg-1). The rats received 28 days chronic mild unexpected stimulation for modeling and intragastric administration. During the experiment

weighting

sucrose preference test and open field test were performed every 7 days. Plasma ACTH and CORT changes in rats were detected using radio immunoassay. Result: Compared with the normal group

the rats in model group showed a slow increase of body weight

decreased sucrose preference index

and significantly higher ACTH and CORT levels(P<0.05)

while in the open field test

the activity

total distance and average speed in rats were increased and the central activity time had been prolonged

but with no statistical difference. Compared with the model group

the sucrose preference index of fluoxetine group and MSNS group was significantly higher(P<0.05)

while ACTH and serum CORT levels were significantly lower(P<0.05)

and the body weight of rats in fluoxetine group was significantly increased on 28th day(P<0.05). Conclusion: MSNS can effectively improve behavior changes of stressed adolescent rats

lower plasma ACTH and serum CORT levels

so it may be an effective method to prevent and treat adolescent stress injuries.