Objective: To study the possible mechanism of Buzhong Yiqi Tang in treatment of spleen Qi deficiency syndrome amyosthenia in rats. Method: A combined method of combined techniques and overstrain were used to establish a spleen Qi deficiency model in rat. Cabbage 15-20 g was given to rats every day

3 mL pig grease was orally given to rats in every other day for 15 days. After a successful modeling

the rats were divided into normal control group

spleen Qi deficiency group

Buzhong Yiqi Tang treatment group(high dose

middle dose

and low dose of 7.10

3.55

1.78 g·kg-1 respectively)

and Buzhong Yiqi Tang was orally administrated for 10 days. The weight

rectal temperature

resistance to cold survival percentage and swimming time of rat were detected

and the expression of p-MLC was detected by Western blot

the value was compared before and after the treatment. Result: The weight

rectal temperature

resistance to cold survival percentage

swimming time and the expression of p-MLC in model group had a significant decrease compared to normal control group. The above mentioned indexes in middle dose and high dose groups of Buzhong Yiqi Tang had a significant increase compared to model group. Conclusion: Buzhong Yiqi Tang showed an up-regulation expression of p-MLC

which may be an mechanism for the treatment of spleen Qi deficiency syndrome amyosthenia in rats.