ABSTRACT
BACKGROUND: Eye acupuncture therapy is a technique used to adjust qi-blood circulation, relax muscles and tendons, and activate col aterals by acupuncture at the acupoints around the eye bal s and in the orbital border. This therapy has been widely used in the clinic because it exhibits remarkable therapeutic effects on many ischemic cerebrovascular diseases. However, the precise mechanism behind this therapy remains poorly understood. Neurotrophic factors are a protein family including neurotrophic factors and brain-derived neurotrophic factors that can regulate neuronal survival, development and functioning. OBJECTIVE: To investigate the effects of eye acupuncture therapy on neurological function and nerve growth factor and brain-derived neurotrophic factor expression in the brain tissue of rat models of cerebral ischemia/reperfusion injury. METHODS: Fifty-four male Sprague-Dawley rats were randomly divided into three groups with 18 rats per group: sham-operated, model and eye acupuncture therapy groups. Rat models of middle cerebral artery occlusion were established by the intraluminal suture method in the model and eye acupuncture therapy groups. Eye acupuncture was performed at the fol owing acupoints liver area, upper-jiao area, lower-jiao area and kidney area located at the internal orbital margin at 2 hours after cerebral ischemia/reperfusion injury. Rat neurological function was evaluated at 3, 7, and 14 days after injury. Nerve growth factor and brain-derived neurotrophic factor expression in the rat brain tissue was detected using immunohistochemical staining method at 1 and 2 weeks after treatment. Cerebral infarct size was determined using TTC staining at 2 weeks after treatment. RESULTS AND CONCLUSION: (1) At 1 and 2 weeks after injury, nerve growth factor and brain-derived neurotrophic factor expression was significantly greater in the eye acupuncture therapy group than in the model group (P < 0.05), but nerve growth factor and brain-derived neurotrophic factor expression in the eye acupuncture therapy group was decreased at 2 weeks after injury compared to that at 1 week after injury. (2) At 7 and 14 days after treatment, neurological function scores in the eye acupuncture therapy group were significantly lowered, and there was significant difference between eye acupuncture therapy and model groups (P < 0.05), but they were significantly higher than those in the sham-operated group (P< 0.05). (3) At 2 weeks after treatment, cerebral infarct size was significantly greater in the eye acupuncture therapy and model groups than in the sham-operated group (P < 0.01), and it was significantly smal er in the eye acupuncture therapy group than in the model group (P < 0.05). (4)These results indicate that eye acupuncture therapy shows neuroprotective effects on ischemic cerebral injury by increasing nerve growth factor and brain-derived neurotrophic factor expression, improving neurological function, and reducing cerebral infarct size.