OBJECTIVETo study the protective effect of electroacupuncture (EA) along the visual conductive pathway for the optic nerve tissue of anterior ischemic optic neuropathy (AION) in terms of the structure and apoptosis.

METHODSThe AION model of right eye was established with laser in 48 New Zealand white ear rabbits. All rabbits were randomly divided into a model group, an acupuncture group and an acupuncture combined with EA group, 16 rabbits in each one. Other 16 normal left eyes were selected as a blank group. Acupuncture and EA of 30 min were used in the corresponding groups for 3 days at the right "Cuanzhu" (BL 2), "Yuyao" (EX-HN 4) and "Qiaomingxue" (Extra), once a day. There was no intervention in the model group and the blank group. The morphological structure and retinal thickness of lining of the optic nerve were detected with HE stain. The expressions of the Bcl-2 and Bax in the retina were detected with immunohistochemistry. And the concentration of tumor necrosis factor-α (TNF-α) in the retina was detected with enzyme linked immunosorbent assay (ELISA).

RESULTSIn the model group, the ganglion cell layer revealed hyperplasia and disorder, and the retina ganglion cells revealed loose arrangements, thin inner nuclear layers, and reduction of cell amounts, some long parts missing cells. However, the above structural damages were much weaker in the acupuncture group and acupuncture combined with EA group. The inner layer of the retina in the model group was thinner than that in the blank group (<0.05). That in the acupuncture combined with EA group showed significant better results than those in the acupuncture and model groups (both<0.05), which was not statistically different from that in the normal group (>0.05). The Bcl-2 count in the model group was lower than that in the blank group (<0.05), and that in the acupuncture combined with EA group was better than those in the acupuncture and model groups (both<0.05), not significantly different from that in the blank group (>0.05). The number of Bax in the model group was higher than that in the blank group (<0.05), and that in the acupuncture combined with EA group was lower than those in the acupuncture and model groups (both<0.05), and was similar to that in the blank group (>0.05). Bcl-2/Bax in the model group was lower than that in the blank group (<0.05). The value in the acupuncture combined with EA group presented better than those in the acupuncture and model groups (both<0.05), which had no difference from that in the blank group (>0.05). TNF-α in the model group was higher than that in the blank group (<0.05), and no such differences were detected between other groups and the model group (both>0.05).

CONCLUSIONSEA along the visual conductive pathway is protective to some extent for optic nerve tissue, which can increase the expression of Bcl-2 and reduce the expression of Bax so as to restrain ganglion cell apoptosis.