Objective: To observe the anti-inflammatory effect of electroacupuncture(EA) at "Quchi"(LI 11) and its influence on cyclooxygenase(COX) expression in carrageenan-induced inflammation rats

so as to study the mechanism of EA in resisting acute inflammation.Methods: Fifty Wistar rats were evenly randomized into control

model

EA

Indomethacin and Rofecoxib groups.Inflammation model was established by subcutaneous injection of 0.1 mL of 2% carrageenan into the right hind paw.The control degree of paw edema(Paw volume 1 h after injection of carrageenan-paw volume 3 h/4 h after injection of carrageenan) was calculated.Concentration of serum PGE_2 was measured by radioimmunoassay.Expression of COX protein in local inflammatory tissues and spleen were detected by Western blotting method.EA(5 mA

15 Hz

continuous waves) was applied to "Quchi"(LI 11) on the affected side for 30 min.Rats of Indomethacin and Rofecoxib groups were fed with Indomethacin and Rofecoxib(3 mg/kg) respectively.Results:Compared with model group

the control rates of paw edema in EA

Indomethacin and Rofecoxib groups 3 h after injection of carrageenan

and in EA and Rofecoxib groups 4 h after injection of carrageenan were significantly higher(P

<

0.05)

showing an apparent inhibitory effect of EA on carrageenan-induced paw edema

especially at the 3

(rd)

hour after administration.Compared with control group

serum PGE_2 content of model group increased significantly(P

<

0.05);while in comparison with model group

PGE_2 contents of EA and Indomethacin groups decreased significantly(P

<

0.05).No significant differences were found among EA

Indomethacin and Rofecoxib groups in the control rates of paw edema and in serum PGE_2 levels(P

>

0.05).Under normal condition

no expression of COX-2 in the spleen tissue of control animals was found

while in the present study

COX-2 expression in the local inflammatory tissues and spleen was significantly upregulated in model group;but EA had no effects on the expression of both COX-1 and COX-2. Conclusion: EA has an anti-inflammatory effect on carrageenan-induced inflammation in rats and resists the development of inflammation by reducing the concentration of serum PGE_2;but EA stimulation has no influence on the expression of both COX-1 and COX-2.