Objective: To study the effects of polysaccharides extracted from Radix Codonopsis Lanceolatae(PCL) on blood glucose and immune function in rats with diabetes mellitus(DM). Method: The rat DM model was established by alloxan injected intraperitoneally. The therapy group rats were administrated PCL at 0.1 or 0.5 g·kg-1 dose. The level of fasting blood glucose was detected by enzyme-chemical method on the 0

7

14

21 day of PCL therapy; the body weight and weight of thymus and spleen were measured for spleen and thymus index; lymphocyte proliferation was observed by MTT method for stimulation index(SI). Result: Compared with normal control group

the level of fasting blood glucose of DM model group significantly increased(P<0.01)

3 weeks later

the thymus extremely withered

spleen lymphocyte transformation ability obviously decreased(P<0.01). Compared with DM model group

PCL could observably reduce blood glucose after 2 weeks treatment (P<0.05). 3 weeks later

thymus index of PCL therapy group enhanced significantly(P<0.05

P<0.01)

and SI increased obviously in the high dose PCL therapy group. Conclusion: PCL can decrease the level of fasting blood glucose in DM rats

meanwhile

cellular immune function can be improved significantly.