Objective To observe the effect of electroacupuncture(EA)stimulation on the levels of a disintegrin and metalloproteinase with thrombospondin motifs-4(ADAMTS-4)protein in the lumbar intervertebral disc tissue and serum in prolapsed lumbar intervertebral disc degeneration(PLIDD)rats

so as to explore its mechanism underlying improvement of intervertebral disc degeneration(IDD).Methods A total of 48 Sprague-Dawley rats were divided into sham operation(n=12)

model(n=18)and EA(n=18)groups.The PLIDD model was established by puncturing the lumbar discs(L4—L5

L5—L6)with a gauge-22 syringe needle.After modeling

EA stimulation was applied to"Pangguangshu"(BL28)

"Zusanli"(ST36)and"Zhijian"for 20 min

6 times per week for 4 weeks.The lumbar intervertebral disc tissue and blood samples were collected at the 4 th

6 th and 8 th week after modeling

respectively.The expression of ADAMTS-4 in the lumbar intervertebral disc tissue was detected by immunohistochemistry and Western blot(WB)

separately.The content of ADAMTS-4 in the serum was detected by ELISA.Results Both immunohistochemical stain and WB showed that the expression levels of lumbar ADAMTS-4 at the 4 th

6 th and 8 th week were significantly up-regulated in the model group relevant to the sham operation group(P<0.01).Following EA treatment

the expression levels of ADAMTS-4 on day 14 and 28 were notably lower in the EA group than in the model group(P<0.05).The serum ADAMTS-4 contents were significantly increased in the model group than in the sham operation group at the 3 time-points(P<0.05

P<0.01)

and considerably decreased in the EA group than in the model group on day 28 after EA intervention(P<0.05).Conclusion EA can down-regulate the ADAMTS-4 expression of lumbar intervertebral disc tissue in PLIDD rats

which may contribute to its effect in relieving lumbar intervertebral disc degeneration.