Objective To observe the effect of proximal and distal acupoint catgut-embedding on the contents of prostaglandin E_2(PGE_2) and prostaglandin F_(2α)(PGF_(2α)) in the uterus

serum Interleukin-2(IL-2) contents and splenic natural killer(NK) cell activity in primary dysmenorrhea(PD) rats

so as to explore the different effects of proximal and distal acupoint catgut-embedding on PD rats. Methods Female Wistar rats were randomly divided into control

model

proximal catgut-embedding and distal catgut-embedding groups

with 8 rats in each group. The PD model was established by subcutaneous injection of estradiol ben-zoate(0.5 mg/rat on the first day and 10

(th)

day

and 0.2 mg/rat from the 2(th) day

and 0.2 mg/rat from the 2

(nd)

to the 9(nd) to the 9

(th)

day) and intraperitoneal injection of oxytocin(2 U/rat

on the 11(th) day) and intraperitoneal injection of oxytocin(2 U/rat

on the 11

(th)

day). Catgut-embedding was applied at bilateral "Guanyuan"(CV4) and "Ciliao"(BL32) in the proximal catgut-embedding group

and bilateral "Sanyinjiao"(SP6) and "Diji"(SP8) in the distal catgut-embedding group. After the treatment

the body writhing times in 30 min and uterine mass were recorded

PGE_2 and PGF_(2α)in uterus and IL-2 in serum were assayed by using ELISA

the activity of NK cell in the spleen was detected using MTT colorimetry. Results Following modeling

the body writhing times of the model group was increased than that of the control group(P

<

0.01); After interventions

the body writhing times were decreased in the proximal and distal catgut-embedding groups than those of the model group(P

<

0.01). Compared with the control group

the uterine mass and uterus PGF_(2α)content were increased(P

<

0.01)

while uterus PGE_2

serum IL-2 and splenic NK cell activity were decreased(P

<

0.01) in the model group. After interventions

the uterine mass and uterus PGF_(2α) were down-regulated(P

<

0.01

P

<

0.05)

while the contents of uterus PGE_2

serum IL-2 and splenic NK cell activity up-regulated(P

<

0.01) in the proximal and distal catgut-embedding groups in contrast to the model group. The content of uterus PGF_(2α) was down-regulated(P

<

0.05) and splenic NK cell activity was up-regulated(P

<

0.01) in the proximal catgut-embedding group than those of the distal catgut-embedding group. Conclusion Both proximal and distal acupoint catgut-embeding can increase PGE_2 and decrease PGF_(2α) in the uterus

increase the level of serum IL-2 and the activity of NK cells in the spleen in PD model rats

thereby achieving analgesic effect. The effect of proximal catgut-embedding is better than that of distal catgut-embedding.