An experimental study of the biomechanics of the middle cerebral artery in acute cerebral infarction

Local cerebrovascular paralysis was found in most cases of cerebral infaction. The extent and severity of vascular paralysis and its effect on contraction-relaxation function of vessels were dependent on the developmental rapidity and duration of vascular

Is decompressive craniectomy for malignant middle cerebral artery infarction of any worth?

Objective: Malignant middle cerebral artery (MCA) infarction is characterized by mortality rate of up to 80%. The aim of this study was to determine the value of decompressive craniectomy in patients presenting malignant MCA infarction compared with those receiving medical treatment alone. Methods: Patients with malignant MCA infarction treated in our hospital between January 1996 and March 2004 were included in this retrospective analysis. The National Institute of Health Stroke Scale (NIHSS)was used to assess neurological status on admission and at one week after surgery. All patients were followed up for assessment of functional outcome by the Barthel index (BI) and modified Rankin Scale (RS) at 3 months after infarction. Results: Ten out of 24patients underwent decompressive craniectomy. The mean interval between stroke onset and surgery was 62.10 h. The mortality was 10.0% compared with 64.2% in patients who received medical treatment alone (P<0.001). The mean NIHSS score before surgery was 26.0 and 15.4 after surgery (P<0.001). At follow up, patients who underwent surgery had significantly better outcome with mean BI of 53.3, RS of 3.3 as compared to only 16.0 and 4.60 in medically treated patients. Speech function also improved in patients with dominant hemispherical infarction. Conclusion: Decompressive craniectomy in patients with malignant MCA infarction improves both survival rates and functional outcomes compared with medical treatment alone. A randomized controlled trial is required to substantiate those findings.

Therapeutic imaging window of cerebral infarction revealed by multisequence magnetic resonance imaging An animal and clinical study

In this study, we established a Wistar rat model of right middle cerebral artery occlusion and observed pathological imaging changes （T2-weighted imaging [T2WI], T2FLAIR, and diffusion-weighted imaging [DWI]） following cerebral infarction. The pathological changes were divided into three phases： early cerebral infarction, middle cerebral infarction, and late cerebral infarction. In the early cerebral infarction phase （less than 2 hours post-infarction）, there was evidence of intracellular edema, which improved after reperfusion. This improvement was defined as the ischemic penumbra. In this phase, a high DWI signal and a low apparent diffusion coefficient were observed in the right basal ganglia region. By contrast, there were no abnormal T2WI and T2FLAIR signals. For the middle cerebral infarction phase （2-4 hours post-infarction）, a mixed edema was observed. After reperfusion, there was a mild improvement in cell edema, while the angioedema became more serious. A high DWI signal and a low apparent diffusion coefficient signal were observed, and some rats showed high T2WI and T2FLAIR signals. For the late cerebral infarction phase （4-6 hours post-infarction）, significant angioedema was visible in the infarction site. After reperfusion, there was a significant increase in angioedema, while there was evidence of hemorrhage and necrosis. A mixed signal was observed on DWI, while a high apparent diffusion coefficient signal, a high T2WI signal, and a high T2FLAIR signal were also observed. All 86 cerebral infarction patients were subjected to T2WI, T2FLAIR, and DWI. MRI results of clinic data similar to the early infarction phase of animal experiments were found in 51 patients, for which 10 patients （10/51） had an onset time greater than 6 hours. A total of 35 patients had MRI results similar to the middle and late infarction phase of animal experiments, of which eight patients （8/35） had an onset time less than 6 hours. These data suggest that defining the ＂therapeutic time window＂ as the time 6 hours after infarction may not be suitable for all patients. Integrated application of MRI sequences including T2WI, T2FLAIR, DW-MRI, and apparent diffusion coefficient mapping should be used to examine the ischemic penumbra, which may provide valuable information for identifying the ＂therapeutic time window＂.

Aortic Dissection Complicated with Fatal Cerebral Infarction: Case Report and Review of Literatures

Acute aortic dissection is a life-threatening condition requiring immediate assessment and therapy. Rarely, aortic dis-section involves carotid arteries and manifest cerebral infarction. Here, we report a case of aortic dissection complicated with fatal cerebral infarction. A 83-year-old man, who suddenly suffered consciousness disturbance and right hemiparesis, was transferred to our hospital for the treatment of stroke. Magnetic resonance image revealed massive cerebral infarction in the left cerebral hemisphere as well as occlusion of the left internal carotid artery. Duplex ultrasonography demonstrated arterial dissection in the bilateral carotid arteries and the blood flow was compromised especially in the left side. Aortic dissection was confirmed by the contrast enhanced computed tomography. He was treated conservatively and died of cerebral hernia three days after the onset. In conclusion, aortic dissection may involve carotid artery and results in cerebral infarction. Ultrasound screening can aid timely diagnosis of aortic dissection and further management.

The Effect of Electro-Acupuncture on Motor Function Recovery in Patients with Acute Cerebral Infarction:A Randomly Controlled Trial

The aim of this study is to investigate the effect of electro-acupuncture treatment in acute phase of cerebral infarction on the motor functions. In this randomly controlled trial, 86 patients were allocated to two groups, the experimental group given clinical and electro-acupuncture treatments for a period of 4 weeks, and the control group given clinical treatment plus active and/or passive functional exercise. The result showed that the level of impairment and disability in both groups were improvement according to the Chinese Stroke Scale, Brunnstrom-Fugl-Meyer score, and Barthel Index throughout the study and 3 months after. The motor functions and the activities of daily living (ADL) were improved significantly in the electro-acupuncture group as compared with the control group (P<0.05). Also, the results showed greater reduction of neurological deficit in the electro-acupuncture group than in the control group. Conclusion: Early acupuncture treatment for acute stroke patients may improve motor functions, and consequently the activities of daily living.

Neuroprotective effect of high-dose hyperbaric oxygenation on rats with acute cerebral infarction in super-early stage:Curative comparison between 9-hour and 18-hour therapeutic protocols

BACKGROUND： Previously, only single short-time low-dose hyperbaric oxygenation （HBO） protocol was administrated to treat acute ischemic stroke in early stage and the conflicting results were obtained. There are few studies to report the outcome of administering long-time （can cover all the natural pathologic progression period） high-dose HBO to treat the disease. OBJECTIVE： To evaluate the therapeutic effect between two kinds of high-dose hyperbaric oxygenation on super-early stage of acute permanent middle cerebral artery occlusion （MCAO） in rats. DESIGN： A randomized controlled experimental study. SETTING： Beijing Tiantan Hospital, Capital Medical University; Beijing Research Institute of Neurosurgery. MATERIALS： Seventy-four male SD rats, aged 2.5 months old, weighing （ 280 ＋ 20） g, were provided by the Animal Institute, Chinese Academy of Medical Sciences. Hyperbaric oxygenation device was hyperbaric air cabin in which there was a self-made pure oxygen animal experimental cabin （made in China）. METHODS： This experiment was carried out in the municipal laboratory of Beijing Tiantan Hospital affiliated to Capital Medical University and Beijing Research Institute of Neurosurgery. ① Experimental intervention： All the rats were developed into models of permanent MCAO by suture embolism. Then, they were randomly divided into two HBO groups （9 hours and 18 hours） and control group, with 24 rats in each as well as 3-hour ultrastructure control group, with 2 rats. After being modeled for 3 hours, rats in the two HBO groups stayed in the hyperbaric cabin for 9 hours and 18 hours, separately. Rats in the 9-hour HBO group inhaled pure oxygen at hours 1, 3, 5, 7 and 9, and hyperbaric air at hours 2, 4, 6 and 8. Rats in the 18-hour HBO group inhaled pure oxygen at hours l, 3, 5, 7, 9, 11, 13, 15 and 17, and hyperbaric air at hours 2, 4, 6, 8, l0 12, 14, 16 and 18. After being created into models, rats in the control group and 3-hour ultrastructure control group breathed room air. ② Experimental evaluation： Neurologic functions of rat models in the 9-hour and 18-hour HBO groups as well as control group were scored by Bederson and Garica two neurological grading systems at hours 14 and 28 and on day 5; Infarct volume of rat models in the two HBO groups and control group was measured at hour 24 and on day 5 with NIH image processing software Image J; The pathological changes of brain tissue in the brain infarct region and its opposite region of rat models in the two HBO groups and 3-hour ultrastructure control group were observed with a Philips EM 208S transmission electron microscope. MAIN OUTCOME MEASURES： ① Neurobehavioral outcome. ② Rat brain infarct volume. ③ Ultrastructure of brain tissue in the ischemic penumbra of infarct models at the different time points RESULTS： ① Neurobehavioral outcome： After treatment, Garica score in the 9-hour and 18-hour HBO groups was significantly higher than that in the control group （P 〈 0.01）. Bederson score on day 5 after modeling in the 9-hour and 18-hour HBO groups was significantly lower than that in the control group （P 〈 0.01）. ② Cerebral infarct volume： Cerebral infarct volume in the 9-hour and 18-hour HBO groups was significantly smaller than that in the control group at hour 24 and on day 5 after modeling （P 〈 0.01）. In the 18-hour HBO group, infarct volume on day 5 after modeling was significantly larger than that at hour 24 after modeling （P 〈 0.05）. ③In the 3-hour ultrastructure control group, astrocyte edema and neuron damage around the capillary in the infarct cerebral tissue significantly relieved in the rats which were subjected to HBO. CONCLUSION： High dose of HBO is highly efficient in reducing infarct volume and improving neurobehavioral outcome of rats with acute cerebral infarction, and also has an important role in inhibiting the pathological progression of ischemic brain tissue after cerebral infarction.

Ipsilateral versus bilateral limb-training in promoting the proliferation and differentiation of endogenous neural stem cells following cerebral infarction in rats

We investigated the effects of ipsilateral versus bilateral limb-training on promotion of endogenous neural stem cells in the peripheral infarct zone and the corresponding cerebral region in the unaffected hemisphere of rats with cerebral infarction. Middle cerebral artery occlusion was induced in Wistar rats. The rat forelimb on the unaffected side was either wrapped up with tape to force the use of the paretic forelimb in rats or not braked to allow bilateral forelimbs to participate in training. Daily training consisted of mesh drum training, balance beam training, and stick rolling training for a total of 40 minutes, once per day. Control rats received no training. At 14 days after functional training, rats receiving bilateral limb-training exhibited milder neurological impairment than that in the ipsilateral limb-training group or the control group. The number of nestin/glial fibrillary acidic protein-positive and nestin/microtubule-associated protein 2-positive cells in the peripheral infarct zone and in the corresponding cerebral region in the unaffected hemisphere was significantly higher in rats receiving bilateral limb-training than in rats receiving ipsilateral limb-training. These data suggest that bilateral limb-training can promote the proliferation and differentiation of endogenous neural stem cells in the bilateral hemispheres after cerebral infarction and accelerate the recovery of neurologic function. In addition, bilateral limb-training produces better therapeutic effects than ipsilateral limb-training.

Effect of Acupuncture on Plasmic Levels of Insulin,Glucagon and Hypercoagulability in NIDDM Complicated by Acute Cerebral Infarction

Twenty-one cases of acute cerebral infarction secondary to NIDDM were treated with acupuncture and conventional therapy, and compared with 16 cases treated with conventional therapy alone. The results showed that acupuncture was more effective in reducing insulin and glucagon levels (P<0.001) and improving hypercoagulability (P<0.05) of blood.

Multimodal magnetic resonance imaging for assessing lacunar infarction after proximal middle cerebral artery occlusion in a canine model

Background A new lacunar infarction model was recently established in beagle dogs through proximal middle cerebral artery （MCA） occlusion by thrombus. This study aimed to characterize the model by multimodal magnetic resonance imaging （MRI） and to investigate its potential role for the future stroke research. Methods The left proximal MCA was embolized with an autologous thrombus in six beagles. Diffusion-weighted imaging （DWI） and T2-weighted imaging （T2Wl） were performed every half hour during the first six hours after occlusion, followed by three time points at 12 hours, 24 hours, and one week. Perfusion-weighted imaging （PWI） and magnetic resonance angiography （MRA） were carried out at six hours, 24 hours and one week. The PWI-DWI mismatch ratio was defined as （PWI-DWl）/DWl ischemic volume. Results Lacunar infarcts induced by MCA occlusion were located in the left caudate nucleus and internal capsule. All the lesions could be detected within two hours by DWI. Lesion volume on DWl increased in a time dependent manner, from （87.19±67.16） mm3 at one hour up to （368.98±217.05） mm3 at 24 hours （P=0.009）, while that on PWl gradually decreased from （7315.00±2054.38） mm3at six hours to （4900.33±1319.71） mm3 at 24 hours and （3334.33±1195.11） mm3 at one week （P=0.002）. The mismatch ratio was 41.93±22.75 at six hours after ischemia, showing ＂extensive mismatch＂, and decreased to 18.10±13.74 at 24 hours （P=0.002）. No MCA recanalization was observed within 24 hours after MCA occlusion. Conclusions Lacunar infarction induced by proximal MCA occlusion could be detected early by DWl and was characterized by extensive PWI-DWl mismatch. Multimodal MRI is useful to demonstrate the natural evolution of PWI-DWl mismatch. This ischemic model could be further used for investigating early thrombolysis in lacunar stroke showing extensive mismatch.

Early postoperative infarction out of the middle cerebral artery distribution following superficial temporal artery-middle cerebral artery bypass： clinical features and pathogenesis

The extracranial-intracranial （EC-IC） bypass surgery has been widely used in the treatment of cerebral ischemia,intracranial aneurysms,and other diseases for more than 40 years.In terms of treating atherosclerotic cerebral ischemia,the surgery is presumed to be helpful for the subgroup of hemodynamic compromise in prevention of subsequent stroke.However,two multicenter trials presented with high perioperative stroke rate and failed to demonstrate the profit of the surgery.1-3 On this point,one of the crucial issues currently is how to lower down the perioperative stroke rate,the centerpiece of which is early postoperative infarction （EPI）.3

A Model of Focal Cortical Infarctionin Rat:Mini mally Invasive Craniotomy

目的建立一种稳定的大鼠脑局灶性梗死模型,以用于脑梗死后神经干细胞移植的长期观察。方法37只大鼠随机分为实验组和对照组。微创法经颞骨局部钻孔开颅,采用直接结扎大脑中动脉终段,同时永久结扎同侧颈总动脉、暂时性夹闭对侧颈总动脉的方法制备大鼠脑梗死模型。通过大鼠脑梗死后的神经功能评分、墨汁灌注、TTC染色、MRI成像结果对该模型进行评价。结果大鼠术后状态良好,实验组大鼠观察4周后死亡率低为6 .25 %。大鼠神经功能评分均为1分,墨汁灌注及TTC染色观察梗死范围局限于皮层,4周后MRI成像测量梗死体积稳定,平均为83 .52 mm3。结论该模型对大鼠创伤小,梗死灶的位置和体积恒定,长期存活率高,为脑梗死后神经干细胞移植的研究提供了一种理想的动物模型。

Apparent diffusion coefficient evaluation for secondary changes in the cerebellum of rats after middle cerebral artery occlusion

Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the cerebellum, which may be relevant to diaschisis. This phenomenon is often analyzed using positron emission tomography and single photon emission CT. However, these methods are expensive and radioactive. Thus, the present study quantified the changes of infarction core and remote regions after unilateral middle cerebral artery occlusion using apparent diffusion coefficient values. Diffu- sion-weighted imaging showed that the area of infarction core gradually increased to involve the cerebral cortex with increasing infarction time. Diffusion weighted imaging signals were initially in- creased and then stabilized by 24 hours. With increasing infarction time, the apparent diffusion co- efficient value in the infarction core and remote bilateral cerebellum both gradually decreased, and then slightly increased 3-24 hours after infarction. Apparent diffusion coefficient values at remote regions （cerebellum） varied along with the change of supratentorial infarction core, suggesting that the phenomenon of diaschisis existed at the remote regions. Thus, apparent diffusion coefficient values and diffusion weighted imaging can be used to detect early diaschisis.

Modified constraint-induced movement therapy alters synaptic plasticity of rat contralateral hippocampus following middle cerebral artery occlusion

Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.

Motor outcomes of patients with a complete middle cerebral artery territory infarct

Detailed knowledge of motor outcomes enables to establish proper goals and rehabilitation strate-gies for stroke patients. Several previous studies have reported functional or motor outcomes in patients with a middle cerebral artery territory infarct. However, little is known about motor outcome in patients with a complete middle cerebral artery territory infarct. In this study, we investigated the motor outcomes in 23 patients with a complete middle cerebral artery territory infarct. All of these patients received comprehensive rehabilitative management, including movement therapy and neuromuscular electrical stimulation of the affected finger extensors and ankle dorsiflexors, for more than 3 months. Motor outcomes were measured at 6 months after stroke onset using the Medical Research Council, Motricity Index, the modified Brunnstrom Classification, and Functional Ambula-tion Category scores. The motor function of the lower extremities was found to be better than that of the upper extremities. After receiving rehabilitation treatments for 3–6 months, about 70% of these patients were able to walk independently （Functional Ambulation Category scores 3）, but no pa-tient achieved functional hand recovery.

Screen-imaging guidance using a modified portable video macroscope for middle cerebral artery occlusion

The use of operating microscopes is limited by the focal length.Surgeons using these instruments cannot simultaneously view and access the surgical field and must choose one or the other.The longer focal length （more than 1 000 mm） of an operating telescope permits a position away from the operating field,above the surgeon and out of the field of view.This gives the telescope an advantage over an operating microscope.We developed a telescopic system using screen-imaging guidance and a modified portable video macroscope constructed from a Computar MLH-10 × macro lens,a DFK-21AU04 USB CCD Camera and a Dell laptop computer as monitor screen.This system was used to establish a middle cerebral artery occlusion model in rats.Results showed that magnification of the modified portable video macroscope was appropriate （5-20 ×） even though the Computar MLH-10 × macro lens was placed 800 mm away from the operating field rather than at the specified working distance of 152.4 mm with a zoom of 1-40 ×.The screen-imaging telescopic technique was clear,life-like,stereoscopic and matched the actual operation.Screen-imaging guidance led to an accurate,smooth,minimally invasive and comparatively easy surgical procedure.Success rate of the model establishment evaluated by neurological function using the modified neurological score system was 74.07%.There was no significant difference in model establishment time,sensorimotor deficit and infarct volume percentage.Our findings indicate that the telescopic lens is effective in the screen surgical operation mode referred to as ＂long distance observation and short distance operation＂ and that screen-imaging guidance using an modified portable video macroscope can be utilized for the establishment of a middle cerebral artery occlusion model and micro-neurosurgery.

Occlusion of the middle cerebral artery Guidance by screen imaging using an EDA-H portable medium-soft electronic endoscope

The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system （RTVRS） using a portable medium-soft electronic endoscope （pmsEE）. The middle cerebral artery in rats was occluded under screen-imaging guidance using a pmsEE RTVRS to reproduce an animal model of human cerebral infarction. The screen imaging of the pmsEE RTVRS was clear, life-like, stereoscopic and synchronous with the actual operation. Screen-imaging guidance led to an accurate, smooth, minimally invasive and comparatively easy surgical procedure. The surgical success rate, time of model establishment, neurological function scores, and infarct volume were similar to those using an operating microscope. These results indicate that the self-designed pmsEE RTVRS could be utilized for portable endoscopic screen-based surgical operations.

Effect of electroacupuncture on expression of Ang/Tie-2 mRNA and protein in rats with acute cerebral infarction

OBJECTIVE: To identify the intervention mechanism of the effect of electroacupuncture on the expression of Ang/Tie-2 m RNA and protein in rats with acute cerebral infarction induced by middle cerebral artery occlusion(MCAO).METHODS: Altogether 120 Wistar rats were subjected to MCAO by inserting a nylon filament, andthen divided into 3 groups: control group, injured group and electroacupuncture group. The injured and electroacupuncture groups were further divided into the following 7 subgroups according to the time after MCAO: 3, 6, 12, 24 h, 3, 7 and 12 d, with 8 rats in each subgroup. The electroacupuncture group was given electroacupuncture treatment at Shuigou(GV 26) instantly after operation. The rats were killed at different time points according to their groups, and then the expression levels of Ang/Tie-2 m RNA and protein were detected using Real-Time polymerase chain reaction and immunohistochemical staining.RESULTS: The m RNA and protein expression levels of Ang/Tie-2 in the electroacupuncture group were significant higher than that in the injured group.CONCLUSION: The results suggested that electroacupuncture could significantly regulate the expression of Ang/Tie-2 m RNA and protein in the rats with acute cerebral infarction induced by MCAO, and enhance angiogenesis after ischemic penumbra.

Clinical Study on the Needling and Drug Treatment of Acute Cerebral Hemorrhage

Researches in recent years have shown that cellular immune factor plays an important role in the generation and development of cerebral hemorrhage1-3.

Influence of Ren and Du meridian electro-acupuncture on neural stem cell proliferation and extracellular signal-regulated kinase pathway in a rat model of focal cerebral ischemia injury

BACKGROUND： Studies have shown that electro-acupuncture at the Ren meridian could improve proliferation of subventricular zone neural stem cells in cerebral-ischemic rats. However, there are few reports on the influence of electro-acupuncture at the Du meridian on neural stem cell proliferation. OBJECTIVE： To observe the influence of electro-acupuncture at Ren and Du meridians on neural stem cell proliferation in the subventricular zone and altered signal transduction in cerebral ischemia rats. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Laboratory of Human Anatomy, Medical College of Sun Yat-sen University from May 2006 to February 2008. MATERIALS： Mouse anti-rat bromodeoxyuridine （BrdU） monoclonal antibody was provided by Sigma, USA; mouse anti-rat nestin monoclonal antibody and extracellular signal-regulated protein kinase （ERK） specific inhibitor PD98059 were provided by Calbiochem, Germany; acupuncture needle was provided by Suzhou Acupuncture Supplies, China. METHODS： A total of 126 rats were randomly assigned to four groups： model （n = 36）, Du meridian （n = 36）, Ren/Du meridian （n = 36）, and Ren/Du meridian ＋ PD98059 （n = 18）. Rats in the Ren/Du meridian ＋ PD98059 group were observed on days 7 （n = 6） and 14 （n = 12） after cerebral ischemia injury. Rats in the model, Du meridian, and Ren/Du meridian groups were observed on days 7, 14, and 28 after cerebral ischemia injury, with 12 rats per group at each time point. Thread occlusion was used to establish middle cerebral artery occlusion models. Electro-acupuncture was performed at Renzhong （DU 26） and Baihui （DU 20） acupoints in the Du meridian group, as well as Chengjiang （RN 24）, Guanyuan （RN 4）, Renzhong, and Baihuiacupoints in the Ren/Du meridian and Ren/Du meridian ＋ PD98059 groups 2 days after model establishment. In addition, electro-acupuncture stimulation with disperse-dense waves was performed, with 30 Hz disperse wave, 100 Hz dense wave, and 5 V intensity for 20 minutes. Rats in the Ren/Du meridian ＋ PD98059 group were treated with 0.2 pg PD98059 injection into the subventricular zone, 2 pL per rat. Rats in the model group were not treated with electro-acupuncture. MAIN OUTCOME MEASURES： BrdU/nestin immunofluorescent staining was used to detect proliferating neural stem cells in the subventricular zone of cerebral ischemia rats; Western blot was used to determine phosphorylated ERK1 and 2 （pERK1/2） expression in the subventricular zone. RESULTS： On days 14 and 28 after cerebral ischemia, there were significantly more BrdU-positive and BrdU/nestin-positive cells in the Ren/Du meridian group compared with the Du meridian group （P 〈 0.05）. PD98059 decreased the number of BrdU-positive and BrdU/nestin-positive cells induced by electro-acupuncture at the/：ten and Du meridians （P 〈 0.05）. On days 7, 14, and 28 after treatment, pERK1/2 expression was significantly greater in the Du meridian and Ren/Du meridian groups compared with the model group （P 〈 0.05）. The promoting effect of electro-acupuncture at Ren and Du meridians on ERK1/2 phosphorylation was superior to electro-acupuncture at the Du meridian alone on day 14 after model induction （P 〈 0.05）. However, PD98059 completely abolished the promoting effect of electro-acupuncture at Ren/Du meridians on pERK1/2 expression （P 〈 0.05）. CONCLUSION： Electro-acupuncture at Ren and Du meridians increased proliferation of subventricular zone neural stem cells, which was related to activation of the ERK pathway in a rat model of cerebral ischemia injury.