Objective To observe the effect of electroacupuncture(EA) at "Jiaji"(EX-B2) on the levels of autophagy and endoplasmic reticulum stress in mice with spinal cord injury(SCI)

so as to explore its mechanism underlying improvement of SCI. Methods A total of 60 female C57 BL/6 mice were randomly divided into sham operation

model and EA groups

which were further divided into 7 d and 14 d subgroups(10 mice in each subgroup). The SCI model was established by pressing the exposed spinal cord(L1) with a vascular clamp for 15 s. EA was applied to bilateral EX-B2 3 h after modeling

once a day for 7 and 14 d

respectively. Basso Mouse Scale(BMS) for locomotion was used to evaluate hindlimb motor function on day 7 and 14 after SCI. H.E. staining was used to observe histopathologic changes of the injured spinal cord tissue

and Western blot employed to detect the expression of glucose regulatory protein-78(GRP78)

Caspase-12

microtubule-associated protein light chain 3 II(LC-II) and P62(also known as sqstm1/Sequestome1) proteins. Immunofluorescence staining was used to detect the immunoacti-vities of spinal CCAAT/enhancer-binding protein(C/EBP) homologous protein(CHOP

an endoplasmic reticulum stress-inducible protein) and P62.Results On the 7

(th)

and 14(th) and 14

(th)

day after SCI

the BMS scores and expression levels of LC3 II protein were significantly down-regulated(P

<

0.05)

and the expression levels of P62

GRP78 and Caspase-12 proteins

the immunoactivities of CHOP and P62 were all significantly up-regulated on both day 7 and 14 in the model group than in the sham operation group(P

<

0.05).Compared with the model group

the BMS scores and the expression levels of LC3 II protein were significantly increased on both day 7 and 14(P

<

0.05)

while the expression levels of P62

GRP78 and Caspase-12 proteins

and the immunoactivities of CHOP and P62 were obviously decreased on day 7 and 14 in the EA group(P

<

0.05). Outcomes of H.E. stain showed that the cells with nuclei pyknosis and swelling and the necrotic cells appeared in the model group

which was relatively fewer in the EA group.Conclusion EA of EX-B2 can improve the locomotor function in SCI mice

which may be related to its effects in up-regulating the expression of LC3 II(to promote cell autophagy)

and down-regulating the expression of P62

GRP78

Caspase-12 and CHOP proteins(to inhibit endoplasmic reticulum stress) in the spinal cord tissue.