Effect of Electroacupuncture on Neuronal Apoptosis and Expression of Nerve Growth Factor Protein in Hypoxic-Ischemic Brain Tissue of Neonatal Rats

Liu Zhenhuan¹Pan Pei Guang¹Qi Yanchao²Zhao Yong²firewood iron³Tang Chunzhi³Wang Qinyu³Yang Junjun³Lam Kam-chuen³

1. Department of Pediatric Neurological Rehabilitation, Nanhai Obstetrics and Gynecology and Children's Hospital Affiliated to Guangzhou University of Chinese Medicine 2. Department of Internal Medicine, Guangzhou Cancer Hospital 3. Laboratory of Acupuncture and Massage College of Guangzhou University of Chinese Medicine

Abstract: Objective: To observe the effect of electroacupuncture on neuronal apoptosis, nerve growth factor protein expression and limb function in neonatal rats with hypoxic ischemia, and to analyze whether the effect is related to acupuncture time. METHODS: The experiment was completed in the clean laboratory of Experimental Animal Center and the laboratory of Acupuncture and Massage College of Guangzhou University of Chinese Medicine from August to October 2005. ① 109 7-day-old newborn SD pups were selected. After ligating the left common carotid artery, the rats were recovered for 2 hours, placed in a transparent airtight container, incorporated into 37 ℃ constant temperature water and introduced hypoxic gas (volume fraction 0.08 oxygen and 0.92 nitrogen) at a speed of 1L/min. After 2.5 hours, the animals were taken out, and the survivors were kept warm for 1 hour for behavior measurement. Those who could not turn over, had abnormal balance or left-handed were regarded as successful models (72 rats). The remaining 24 rats were set as sham operation group: only the left common carotid artery was isolated without ligation and hypoxia treatment. Seventy-two successful rats were randomly divided into three groups: hypoxia-ischemia acupuncture group I, hypoxia-ischemia acupuncture group II, and model group, with 24 rats in each group. The rats were selected as Baiwill, affected temporal I needle, Neiguan, Quchi, Zusanli and Yongquan. Hypoxic-ischemic acupuncture group I started acupuncture 24h after modeling, and only the limbs (position, the head (position) was added on the 8th day. Acupuncture was started on the 8th day after the hypoxic-ischemic acupuncture group II was modeled, and the head and body needles were synchronized. Both groups were treated with acupuncture needles in Neiguan and Yongquan, without leaving needles, and then needle heads and Quchi and Zusanli. Baiwei, Temporal I needle and Quchi, Zusanli are connected with G6805-II electroacupuncture instrument, continuous wave, frequency 5~10Hz, duration 10min. 1 times/d, hypoxia ischemia acupuncture group I continuous acupuncture 20d, hypoxia ischemia acupuncture group II continuous acupuncture 13d. The method of acupuncture in the sham operation group was the same as that in the hypoxic-ischemic acupuncture group I, and the model group was only modeled without any treatment. ③ On the 7th, 14th and 21st day after operation, the adhesive tape was stuck on the ventral side of the two forepaws of rats, and the time taken to tear off the adhesive tape was recorded. ④ On the 21st day after operation, 10 rats were randomly selected from each group for the following tests: the apoptosis of neurons in the frontal cortex and hippocampus and the expression of nerve growth factor in the hippocampus were determined by in situ end labeling and immunohistochemistry, respectively, and the number of apoptotic neurons and the expression of nerve growth factor immunoreactive cells were counted by image analyzer under light microscope (× 400). ⑤ The comparison of the rate uses the test of 2, and the comparison of the multi-means between groups uses the analysis of variance (F-q test). Results: 109 rats were included, 13 rats were lost due to model failure, and no animals died in the sham operation group. Seven days after modeling, 2,5, and 3 died in the hypoxia-ischemia acupuncture group I, the hypoxia-ischemia acupuncture group II, and the model group, respectively; 7 to 14 days after modeling, 2,2, and 4 died in the three groups, respectively; 14 to 21 days after modeling, 0,0, and 2 died in the three groups, respectively. ① Neuronal apoptosis in hippocampus and frontal lobe cortex of rats: The number of positive cells stained by in situ end labeling in hippocampus and frontal lobe cortex of rats in the two electroacupuncture treatment groups was significantly reduced, and the difference was significant compared with the model group (P<0.05). And the apoptosis count of nerve cells in the hypoxic ischemic ten electroacupuncture group I was significantly lower than that in the hypoxic ischemic ten electroacupuncture group II (P<0.05). ② Expression of NGF protein in hippocampal neurons of rats: The expression of NGF protein in the two electroacupuncture treatment groups was significantly enhanced, which was significantly higher or higher than that in the sham operation group and the model group (P<0.01), and that in the hypoxic-ischemic acupuncture group I was significantly higher or higher than that in the hypoxic-ischemic acupuncture group II (P<0.01). ③ On the 7th day after operation, the time taken to tear off adhesive tape in hypoxic-ischemic acupuncture group I was significantly shorter than that in model group (P<0.01). On the 14th day after operation, the model group was significantly longer than the other three groups (P<0.05-0.01). On the 21st day after operation, the forelimb function of the two acupuncture groups and the model group was significantly improved, and the hypoxic-ischemic acupuncture group I was basically close to normal (compared with sham operation group, the difference was not significant, P>0.05), but the model group was still significantly longer than the hypoxic-ischemic acupuncture group I and the sham-operated group (P<0.01). Conclusion: Electroacupuncture can inhibit the apoptosis of neurons in the brain after cerebral hypoxia-ischemia, enhance the expression of nerve growth factor in the brain tissue of rats with hypoxic-ischemic injury, improve limb function, and has a certain protective effect on hypoxic-ischemic brain damage, and the earlier the intervention, the better the effect.Restore

Key words:Hypoxia-ischemia, brain/acupuncture therapy;Electroacupuncture;Apoptosis;Nerve growth factors;

• Album: Medical and Health Technology
• Topic: Traditional Chinese Medicine
• Classification number: R245

Electroacupuncture on hypoxic-ischemic brain tissue of neonatal rats... the effect of nerve growth factor protein expression