[Effects of Huangqi Guizhi Wuwu Decoction given by different administration methods on rats with frostbite and the mechanism].

Objective: To establish a rat model of frostbite and to evaluate the effects of different administration methods of Huangqi Guizhi Wuwu Decoction (HGWD), a compound traditional Chinese herbal medicine for warming meridians to disperse cold, on rats with frostbite.
Methods: Frostbite in rats was induced by the method of soaking feet in hypothermia ethanol-water mixture. Levels of interleukin-6 (IL-6), tumor necrosis factor-beta (TNF-beta), thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin F(1alpha) (6-keto-PGF(1alpha)) in serum of rats treated with different administration methods of HGWD, such as oral administration (Oral HGWD), soak (Soak HGWD), and oral administration plus soak (Oral-soak HGWD), were tested by enzyme-linked immunosorbent assay.
Results: IL-6, TNF-beta, TXB(2) levels were significantly higher (P<0.01) and 6-keto-PGFbeta level was lower (P<0.01) in serum of rats in the untreated group than in the normal control group. Compared with the untreated group, the level of IL-6 obviously decreased (P<0.05) in serum of the rats treated by oral HGWD, while no significant decrease (P>0.05) was observed in the soak HGWD group, and there was no interaction (P>0.05) between the two administration methods in regulating the level of IL-6. The levels of TNF-beta obviously decreased (P<0.01, P<0.05) in serum of the rats treated by oral and soak HGWD, and there was interaction between the two administration methods. The level of TNF-beta in the oral HGWD group was significantly lower than that in the soak HGWD group (P<0.01). Compared with the untreated group, level of TXB(2) in oral HGWD or soak HGWD group did not decrease significantly (P>0.05) and there was no interaction (P>0.05) between the two administration methods. The level of 6-keto-PGF(1alpha) was obviously increased (P<0.01) in serum of the rats treated by oral HGWD, while there was no significant decrease (P>0.05) in the soak HGWD group as compared with the untreated group, and there was interaction (P<0.05) between the two administration methods in regulating the level of 6-keto-PGF(1alpha).
Conclusion: Rats with frostbite has immunologic dysfunction and a state of forming thrombus easily. The oral-soak HGWD can improve frostbite of local skin in rats. The therapeutic mechanism of HGWD may be to regulate the dysfunction of immune system and the imbalance of TXB(2)-PGF(1alpha).