Electroacupuncture pretreatment enhances the calcium efflux activity of Na+/Ca2+ exchanger to attenuate cerebral injury by PI3K/Akt-mediated NCX1 upregulation after focal cerebral ischaemia.

Electroacupuncture pretreatment is considered as an optimal strategy for inducing cerebral ischaemic tolerance. However, the underlying neuroprotective mechanism of this approach has never been explored from the perspective of calcium homeostasis. Intracellular calcium overload is a key inducer of cascade neuronal injury in the early stage after cerebral ischaemia attack and the Na+/Ca2+ exchanger (NCX) is the main plasma membrane calcium extrusion pathway maintaining post-ischaemic calcium homeostasis. This study aims to investigate whether the regulation of NCX-mediated calcium transport contributes to the cerebroprotective effect of electroacupuncture pretreatment against ischaemic injury and to elucidate the underlying mechanisms involved in this process. Following five days of repeated electroacupuncture stimulation on Baihui (GV20), Neiguan (PC6), and Sanyinjiao (SP6) acupoints in rats, in vivo and in vitro models of cerebral ischaemia were induced through middle cerebral artery occlusion and oxygen/glucose deprivation (OGD), respectively. Firstly, we verified the neuroprotective effect of electroacupuncture pretreatment from the perspective of neurological score, infarct volume and neuronal apoptosis. Our findings from brain slice patch-clamp indicated that electroacupuncture pretreatment enhanced the Ca2+ efflux capacity of NCX after OGD. NCX1 expression in the ischaemic penumbra exhibited a consistent decline from 1 to 24 h in MCAO rats. Electroacupuncture pretreatment upregulated the expression of NCX1, especially at 24 h, and silencing NCX1 by short hairpin RNA (shRNA) administration reversed the protective effect of electroacupuncture pretreatment against cerebral ischaemic injury. Furthermore, we administered LY294002, a phosphatidylinositol 3 kinase (PI3K) inhibitor, prior to inducing ischaemia to investigate the upstream regulatory mechanism of electroacupuncture pretreatment on NCX1 expression. Electroacupuncture pretreatment activates PI3K/Akt pathway, leading to an increase in the expression of NCX1, which facilitates calcium extrusion and exerts a neuroprotective effect against cerebral ischaemia. These findings provided a novel insight into the prevention of ischemic stroke and other similar conditions characterized by brain ischaemia or hypoperfusion.

Electroacupuncture pretreatment alleviates rats cerebral ischemia-reperfusion injury by inhibiting ferroptosis.

Objective: To explore the preventive effect of electroacupuncture pretreatment on stroke in rats by inhibiting ferroptosis and oxidative stress. Methods: Rats were randomly assigned to the sham, middle cerebral artery occlusion/reperfusion (MCAO/R), MCAO/R + EP, MCAO/R + EP + erastin, and MCAO/R + EP + ferrostatin 1 groups. Daily electroacupuncture was performed 2 weeks before establishing the MCAO/R model utilizing the modified Zea Longa suture method. Rats were sacrificed 1 day after reperfusion, and brain tissues were collected. They were prepared for hematoxylin and eosin staining, prussian blue staining, transmission electron microscope. Measurement of total iron levels using a commercial kit, detection of malondialdehyde (MDA) and superoxide dismutase (SOD) levels by ELISA, and examination of 15-lox2, GPX4, SLC7A11, ACSL4, and TFR1 by western blotting. Results: Compared with sham rats, cerebral infarction size was dramatically larger in MCAO/R rats. Moreover, the MCAO/R group displayed damaged mitochondria with a disarranged structure of cristae; free iron, total iron levels, and oxidative stress were significantly higher. Cerebral pathological lesions, oxidative stress, total iron levels, and protein levels of ACSL4, TFR1, and 15-lox2 were significantly reduced in the MCAO/R + EP and MCAO/R + EP + ferrostatin 1 groups, while the protective effect of electroacupuncture pretreatment on cerebral ischemia-reperfusion injury was inhibited by treatment with the ferroptosis activator erastin. Conclusion: Electroacupuncture pretreatment can protect rats from cerebral ischemia-reperfusion injury by reducing the area of cerebral infarction and inhibiting ferroptosis and oxidative stress.

Electroacupuncture pretreatment mediates sympathetic nerves to alleviate myocardial ischemia-reperfusion injury via CRH neurons in the paraventricular nucleus of the hypothalamus.

BACKGROUND: Myocardial ischemia-reperfusion can further exacerbate myocardial injury and increase the risk of death. Our previous research found that the paraventricular nucleus (PVN) of the hypothalamus plays a crucial role in the improvement of myocardial ischemia-reperfusion injury (MIRI) by electroacupuncture (EA) pretreatment, but its mechanism of action is still unclear. CRH neurons exhibit periodic concentrated expression in PVN, but further research is needed to determine whether they are involved in the improvement of MIRI by EA pretreatment. Meanwhile, numerous studies have shown that changes in sympathetic nervous system innervation and activity are associated with many heart diseases. This study aims to investigate whether EA pretreatment improves MIRI through sympathetic nervous system mediated by PVNCRH neurons. METHODS: Integrated use of fiber-optic recording, chemical genetics and other methods to detect relevant indicators: ECG signals were acquired through Powerlab standard II leads, and LabChart 8 calculated heart rate, ST-segment offset, and heart rate variability (HRV); Left ventricular ejection fraction (LVEF), left ventricular short-axis shortening (LVFS), left ventricular end-systolic internal diameter (LVIDs) and interventricular septal thickness (IVSs) were measured by echocardiography; Myocardial infarct area (IA) and area at risk (AAR) were calculated by Evans-TTC staining. Pathological changes in cardiomyocytes were observed by HE staining; Changes in PVNCRH neuronal activity were recorded by fiber-optic photometry; Sympathetic nerve discharges were recorded for in vivo electrophysiology; NE and TH protein expression was assayed by Western blot. RESULTS: Our data indicated that EA pretreatment can effectively alleviate MIRI. Meanwhile, we found that in the MIRI model, the number and activity of CRH neurons co labeled with c-Fos in the PVN area of the rat brain increased, and the frequency of sympathetic nerve discharge increased. EA pretreatment could reverse this change. In addition, the results of chemical genetics indicated that inhibiting PVNCRH neurons has a similar protective effect on MIRI as EA pretreatment, and the activation of PVNCRH neurons can counteract this protective effect. CONCLUSION: EA pretreatment can inhibit PVNCRH neurons and improve MIRI by inhibiting sympathetic nerve, which offers fresh perspectives on the application of acupuncture in the management of cardiovascular disease.

A New Target of Electroacupuncture Pretreatment Mediated Sympathetic Nervous to Improve MIRI: Glutamatergic Neurons in Fastigial Nucleus of the Cerebellum.

Ischemic heart disease is a fatal cardiovascular disease that irreversibly impairs the function of the heart, followed by reperfusion leading to a further increase in infarct size. Clinically, we call it myocardial ischemia-reperfusion injury (MIRI). A growing number of clinical observations and experimental studies have found electroacupuncture (EA) to be effective in alleviating MIRI. This study attempts to investigate whether glutamatergic neurons in fastigial nucleus (FN) of the cerebellum are involved in EA pretreatment to alleviate MIRI via sympathetic nerves, and the potential mechanisms of EA pretreatment process. A MIRI model was established by ligating the coronary artery of the left anterior descending branch of the heart for 30 minutes, followed by 2 hours of reperfusion. Multichannel physiological recordings, electrocardiogram, cardiac ultrasound, chemical genetics, enzyme-linked immunosorbent assay and immunofluorescence staining methods were combined to demonstrate that EA pretreatment inhibited neuronal firing and c-Fos expression in FN of the cerebellum and reduced cardiac sympathetic firing. Meanwhile, EA pretreatment significantly reduced cardiac ejection fraction (EF), shortening fraction (SF), percentage infarct area, decreased myocardial norepinephrine (NE), creatine kinase isoenzyme MB (CK-MB) concentrations, and improved MIRI-induced myocardial tissue morphology. The results were similar to the inhibition of glutamatergic neurons in FN. However, the activation of glutamatergic neurons in FN diminished the aforementioned effects of EA pretreatment. This study revealed that glutamatergic neurons in FN of the cerebellum is involved in EA pretreatment mediated sympathetic nervous and may be a potential mediator for improving MIRI.

Electroacupuncture Pretreatment Attenuates Learning Memory Impairment Induced by Repeated Propofol Exposure and Modulates Hippocampal Synaptic Plasticity in Rats.

Background: Recurrent propofol anesthesia in the peak of neurodevelopment may lead to learning-memory decline. This study aimed to examine the efficacy of electroacupuncture pretreatment in ameliorating the aforementioned learning memory deficits and to explore its underlying mechanisms in a rat model of repeated propofol exposure. Methods: 10-day-old Sprague Dawley rats were randomly assigned to five groups: the control, fat emulsion, propofol, electroacupuncture pretreatment and electroacupuncture pretreatment combined with propofol groups. The electroacupuncture pretreatment involved three consecutive daily sessions, while propofol was received intraperitoneally once daily for five days. Following the modeling period, the rats' learning-memory performance was assessed using the New Novel Arm Y-maze, New Object Recognition, and Morris Water Maze. The Nissl staining method was used to observe the development of hippocampal neurons, while Golgi staining was employed to observe hippocampal synaptic development. Results: The electroacupuncture pretreatment significantly attenuated the learning and memory impairment induced by recurring propofol exposure in rats. Additionally, it facilitated the development of hippocampal neurons and synaptic plasticity in the hippocampus. Immunofluorescence and Western Blot analyses were conducted to detect the expression of proteins related to apoptosis, learning memory, and synaptic plasticity. In the propofol group, the pro-apoptotic factors Caspase-3 and Bax was up-regulated, while the anti-apoptotic factor Bcl-2 was down-regulated, as compared to the blank group. Additionally, the phosphorylated cAMP-response element binding protein (pCREB), brain-derived neurotrophic factor (BDNF), synaptophysin, and growth associated protein-43 (GAP-43) was significantly decreased. In contrast, the electroacupuncture pretreatment combined with propofol group exhibited decreased the Caspase-3 and Bax and increased the Bcl-2, as compared to the propofol group, meanwhile, the pCREB, BDNF, Synaptophysin and GAP-43 was increased. Conclusion: Our findings indicate that electroacupuncture pretreatment can alleviate the learning and memory impairment induced by recurring propofol exposure in rats. This is achieved by enhancing hippocampal synaptic plasticity, activating the pCREB/BDNF pathway and inhibiting neuronal apoptosis.

[Effect of electroacupuncture pretreatment on ferroptosis in neurons of rats with cerebral ischemia-reperfusion injury].

OBJECTIVE: To observe the effect of electroacupuncture（EA）preconditioning on ferroptosis in rats with cerebral ischemia-reperfusion injury （CIRI）, so as to explore the neuroprotective mechanism of EA preconditioning. METHODS: Male SD rats were randomly divided into sham operation, model, EA, inhibitor and inducer groups with 20 rats in each group. The CIRI model was established by modified Zea Longa occlusion of the middle cerebral artery. Before modeling, EA treatment （2 Hz/15 Hz, 1-2 mA） was applied to "Baihui"（GV20）, "Fengfu"（GV16） and "Dazhui"（GV14） for rats of the EA group, 20 min a day for 7 consecutive days. Rats of the inhibitor group were intraperitoneally injected with ferristatin-1（25 mg/kg）at a slow and uniform rate. Rats of the inducer group were intraperitoneally injected with Erastin（100 mg/kg） after 7 days of EA preconditioning, once every 2 h for a total of 4 times. The CIRI models were prepared 2 d later after the above interventions finished by thread-occlusion. The degree of neurological impairment was evaluated by modified Zea Longa score. The percentage of infarct size was calculated by TTC staining. The ultrastructure of neurons in hippocampus was observed by transmission electron microscope. The contents of ferrous ion （Fe2+）, malondialdehyde （MDA） and glutathione （GSH） in cerebral tissue and reactive oxygen species （ROS） in serum were determined by biochemical method. The changes of mitochondrial membrane potential in rats brain tissues were detected by flow cytometry. The mRNA and protein expression levels of glutathione peroxidase 4 （GPX4）, acyl-CoA synthetase long-chain family member 4 （ACSL4）, transferrin receptor （TFRC）, 15-lipoxygenase （15-LOX） and cyclooxygenase-2 （COX-2） in the ischemic hippocampal region of CIRI rats were detected by real-time quantitative PCR and Western blot, respectively. RESULTS: Compared with the sham operation group, the neurological impairment score, the percentage of cerebral infarction area, the contents of MDA and Fe2+ in cerebral tissue as well as ROS in serum, the protein and mRNA expression levels of ACSL4, TFRC, 15-LOX, COX-2 in hippocampal tissue were increased （P<0.01）, while the content of GSH in cerebral tissue, the protein and mRNA expression levels of GPX4 in hippocampal tissue were decreased （P<0.01）, and mitochondria in brain tissue were significantly damaged （P<0.01） in the model group. Compared with the model group, the above indexes were all reversed （P<0.05, P<0.01） in the EA group and inhibitor group. Compared with the EA group, the neurological impairment score, the percentage of cerebral infarction area, the contents of MDA and Fe2+ in cerebral tissue as well as ROS in serum, the protein and mRNA expression le-vels of ACSL4, TFRC, 15-LOX, COX-2 in hippocampal tissue were increased （P<0.05, P<0.01）, while the content of GSH in cerebral tissue, the protein and mRNA expression levels of GPX4 in hippocampal tissue were decreased （P<0.01, P<0.05）, and mitochondria in brain tissue were significantly damaged （P<0.05） in the inducer group. CONCLUSION: EA preconditioning has neuroprotective effect on CIRI rats, which may be related to inhibiting ACSL4/TFRC/15-LOX/COX-2 expression and increasing GSH/GPX4 expression.

[Effects of electroacupuncture pretreatment on GABAA receptor of fastigial nucleus and sympathetic nerve activity in rats with myocardial ischemia reperfusion injury].

OBJECTIVE: To observe the effects of electroacupuncture (EA) pretreatment on cardiac function, sympathetic nerve activity, indexes of myocardial injury and GABAA receptor in fastigial nucleus in rats with myocardial ischemia reperfusion injury (MIRI), and to explore the neuroregulatory mechanism of EA pretreatment in improving MIRI. METHODS: A total of 60 male SD rats were randomly divided into a sham operation group, a model group, an EA group, an agonist group and an agonist+EA group, 12 rats in each group. The MIRI model was established by ligation of the left anterior descending coronary artery. EA was applied at bilateral "Shenmen" (HT 7) and "Tongli" (HT 5) in the EA group and the agonist+EA group, with continuous wave, in frequency of 2 Hz and intensity of 1 mA, 30 min each time, once a day for 7 consecutive days. After intervention, the MIRI model was established. In the agonist group, the muscone (agonist of GABAA receptor, 1 g/L) was injected in fastigial nucleus for 7 consecutive days before modeling, 150 µL each time, once a day. In the agonist+EA group, the muscone was injected in fastigial nucleus 30 min before EA intervention. The data of electrocardiogram was collected by PowerLab standard Ⅱ lead, and ST segment displacement and heart rate variability (HRV) were analyzed; the serum levels of norepinephrine (NE), creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) were detected by ELISA; the myocardial infarction area was measured by TTC staining; the morphology of myocardial tissue was observed by HE staining; the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were detected by immunohistochemistry and real-time PCR. RESULTS: Compared with the sham operation group, in the model group, ST segment displacement and ratio of low frequency to high frequency (LF/HF) of HRV were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber was broken and interstitial edema was serious, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01). Compared with the model group, in the EA group, ST segment displacement and LF/HF ratio were decreased (P<0.01), HRV frequency domain analysis showed reduced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were decreased (P<0.01), the percentage of myocardial infarction area was decreased (P<0.01), myocardial fiber breakage and interstitial edema were lightened, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were decreased (P<0.01). Compared with the EA group, in the agonist group and the agonist+EA group, ST segment displacement and LF/HF ratio were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber breakage and interstitial edema were aggravated, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01). CONCLUSION: EA pretreatment can improve the myocardial injury in MIRI rats, and its mechanism may be related to the inhibition of GABAA receptor expression in fastigial nucleus, thereby down-regulating the excitability of sympathetic nerve.

[Effects of electroacupuncture pretreatment on NLRP3 inflammasome in mice with ventilator-induced lung injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) pretreatment on inflammatory response in ven-tilator-induced lung injury (VILI) mice, so as to explore the underlying mechanism of EA pretreatment on prevention of VILI. METHODS: C57BL/6 mice were randomly divided into sham-operation group, model group, EA group and sham-acupoint group，with 8 mice in each group. The VILI model was established by ventilation with high tidal volume. Mice in the EA group and sham-acupoint group were given EA at "Zusanli" (ST36)and "Feishu"(BL13) or non-acupoints (located at 1-2 cm on both sides of the tail root of the proximal trunk) before mechanical ventilation, 30 min each time, once a day for 5 days. Arterial blood was collec-ted for blood gas analysis, the total protein content in bronchoalveolar lavage fluid (BALF) was detected by BCA method. The contents of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) in BALF were detected by ELISA. Lung injury score was determined after HE staining. The protein expression levels of nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3), apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) and Caspase-1 in lung tissue was detected by Western blot. RESULTS: Compared with the sham-operation group, the arterial partial pressure of oxygen and oxygenation index were decreased(P<0.05), the levels of total protein, IL-1ß and IL-18 in BALF, the W/D value and the pathological injury score of lung tissue and the protein expression levels of NLRP3, Caspase-1 and ASC were increased(P<0.05)in the model group. Following the interventions, the above mentioned increased or decreased indicators were reversed(P<0.05) in the EA group rather than in the sham-acupoint group. CONCLUSION: EA pretreatment of ST36 and BL13 can reduce the damage of lung tissue caused by mechanical ventilation, which may be related to its effect in reducing the expression of NLPR3 inflammasome related proteins, reducing the activation of inflammasome, and thereby reducing the inflammatory response.

Electroacupuncture pretreatment protects septic rats from acute lung injury by relieving inflammation and regulating macrophage polarization.

BACKGROUND: Macrophage polarization toward the M2 phenotype may attenuate inflammation and have a therapeutic effect in acute lung injury (ALI). OBJECTIVE: To investigate the role of electroacupuncture (EA) pretreatment on the inflammatory response and macrophage polarization in a septic rat model of lipopolysaccharide (LPS)-induced ALI. METHODS: Male Sprague Dawley rats (n = 24) were randomly divided into three groups (n = 8 each): control (Ctrl), ALI (LPS) and pre-EA (LPS + EA pretreatment). ALI and pre-EA rats were injected with LPS via the caudal vein. Pulmonary edema was assessed by left upper pulmonary lobe wet-to-dry (W/D) ratios. Lung injury scores were obtained from paraffin-embedded and hematoxylin and eosin-stained sections of the left lower pulmonary lobe. Inflammatory activation was quantified using serum tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, transforming growth factor (TGF)-ß and IL-10 levels measured by enzyme linked immunosorbent assay (ELISA). Macrophage phenotype was determined by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. RESULTS: Mean lung W/D ratio was significantly lower and serum IL-1ß levels were decreased in pre-EA rats compared to ALI rats (P < 0.05). TNF-α mRNA expression was decreased and mannose receptor (MR) and Arg1 mRNA expression was increased in the lung tissues of pre-EA rats compared to ALI rats (P < 0.01). Arg1 protein expression was similarly increased in the lung tissues of pre-EA rats compared to ALI rats (P < 0.05). CONCLUSION: EA pretreatment may play a protective role by promoting macrophage polarization to the M2 phenotype in a septic rat model of LPS-induced ALI.

Effects of electroacupuncture pretreatment on GABAA receptor of fastigial nucleus and sympathetic nerve activity in rats with myocardial ischemia reperfusion injury / 中国针灸

OBJECTIVE@#To observe the effects of electroacupuncture (EA) pretreatment on cardiac function, sympathetic nerve activity, indexes of myocardial injury and GABAA receptor in fastigial nucleus in rats with myocardial ischemia reperfusion injury (MIRI), and to explore the neuroregulatory mechanism of EA pretreatment in improving MIRI.@*METHODS@#A total of 60 male SD rats were randomly divided into a sham operation group, a model group, an EA group, an agonist group and an agonist+EA group, 12 rats in each group. The MIRI model was established by ligation of the left anterior descending coronary artery. EA was applied at bilateral "Shenmen" (HT 7) and "Tongli" (HT 5) in the EA group and the agonist+EA group, with continuous wave, in frequency of 2 Hz and intensity of 1 mA, 30 min each time, once a day for 7 consecutive days. After intervention, the MIRI model was established. In the agonist group, the muscone (agonist of GABAA receptor, 1 g/L) was injected in fastigial nucleus for 7 consecutive days before modeling, 150 μL each time, once a day. In the agonist+EA group, the muscone was injected in fastigial nucleus 30 min before EA intervention. The data of electrocardiogram was collected by PowerLab standard Ⅱ lead, and ST segment displacement and heart rate variability (HRV) were analyzed; the serum levels of norepinephrine (NE), creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) were detected by ELISA; the myocardial infarction area was measured by TTC staining; the morphology of myocardial tissue was observed by HE staining; the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were detected by immunohistochemistry and real-time PCR.@*RESULTS@#Compared with the sham operation group, in the model group, ST segment displacement and ratio of low frequency to high frequency (LF/HF) of HRV were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber was broken and interstitial edema was serious, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01). Compared with the model group, in the EA group, ST segment displacement and LF/HF ratio were decreased (P<0.01), HRV frequency domain analysis showed reduced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were decreased (P<0.01), the percentage of myocardial infarction area was decreased (P<0.01), myocardial fiber breakage and interstitial edema were lightened, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were decreased (P<0.01). Compared with the EA group, in the agonist group and the agonist+EA group, ST segment displacement and LF/HF ratio were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber breakage and interstitial edema were aggravated, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01).@*CONCLUSION@#EA pretreatment can improve the myocardial injury in MIRI rats, and its mechanism may be related to the inhibition of GABAA receptor expression in fastigial nucleus, thereby down-regulating the excitability of sympathetic nerve.

[Electroacupuncture pretreatment alleviates apoptosis of renal tubular epithelia cells by down-regulating expression of TRPC6 in hyperglycemic mice].

OBJECTIVE: To observe the effect of electroacupuncture (EA) pretreatment on apoptosis of renal tubular epithelial cells in mice with hyperglycemia, so as to explore its mechanisms underlying protecting the kidney from hyperglycemia-induced injury. METHODS: Eighty male C57BL/6 mice were equally and randomly divided into control, model, EA and sham EA groups. The hyperglycemia model was established by intraperitoneal injection of streptozocin (STZ, 50 mg·kg-1·d-1) for 5 consecutive days. Before modeling, EA (2 Hz/15 Hz, 0.3-0.5 mA) was applied to bilateral "Zusanli" (ST36) and "Shenshu" (BL23) for 30 min, once daily for 7 days, while mice in the sham EA group were treated with the same acupoints but without electrical stimulation. The blood glucose values were measured after fasting for 6 hours after 3 days of modeling. The degree of renal tissue injury was observed by microscope after H.E. staining, and the apoptosis level of renal tubular epithelial cells observed by TUNEL staining. The expression levels of transient receptor potential channel 6 (TRPC6) and related apoptotic proteins Caspase-3, Bax and Bcl-2 in the renal tissue were detected by Western blot and immunohistochemistry, separately. RESULTS: Compared with the control group, the blood glucose content and the expression levels of TRPC6, Caspase-3 and Bax proteins, as well as the level of the renal apoptotic cells were significantly increased (P<0.001, P<0.000 1), while the expression level of Bcl-2 protein and the ratio of Bcl-2/Bax were remarkably decreased in the model group (P<0.000 1). In comparison with the model and sham EA groups, the blood glucose content, percentage of apoptotic cells and the expression levels of TRPC6, Caspase-3 and Bax were significantly decreased (P<0.01, P<0.000 1, P<0.05, P<0.001), and the expression level of Bcl-2 and the ratio of Bcl-2/Bax were apparently increased in the EA group (P<0.01, P<0.05, P<0.001). HE statin showed abnormal dilation of the capillary lumen and disappearance of the proximal tubules in the model group, which was relatively milder in the EA group. CONCLUSION: EA pretreatment can lower blood glucose level and reduce renal apoptosis in hyperglycemia mice, which may be related to its effects in down-regulating the expression of TRPC6 and Caspase-3 and up-regulating the ratio of Bcl-2/Bax.

[Effect of electroacupuncture preconditioning on myocyte apoptosis in myocardial ischemia-reperfusion injury rats based on FXR/SHP pathway].

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on left-cardiac function, contents of serum TNF-α and IL-6 and expression of myocardial farnesoid X receptor(FXR), small heterodimer partner (SHP), apoptosis inducing factor (AIF) and heat shock proteins 70 (HSP70) genes in myocardial ischemia-reperfusion injury (MIRI) rats, so as to explore its mechanisms underlying improvement of ischemic myocardial injury. METHODS: Forty male Wistar rats were randomly divided into normal control, sham operation, MIRI model and EA pretreatment groups, with 10 rats in each group. Rats of the sham operation group received exposure of the thorax and heart. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery (LAD). EA (2 Hz/100 Hz and 1 mA) was applied to bilateral "Neiguan" (PC6), "Zusanli" (ST36) and "Guanyuan" (CV4) for 20 min, once a day for 7 days. The left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP)and maximal rates of rise and fall of left ventricular pressure (±dp/dtmax) were detected, the contents of serum TNF-α and IL-6 were detected by using enzyme-linked immunosorbent assay (ELISA), and the expression of FXR, SHP, AIF and HSP70 apoptotic genes in the myocardial tissue were measured by fluorescent quantitative RT-PCR. RESULTS: Compared with the normal control group, the LVEDP, contents of serum TNF-α and IL-6, and the expression levels of myocardial FXR, SHP, AIF and HSP70 mRNAs were significantly increased (P<0.05), while LVSP and ±dp/dtmax levels were obviously decreased in the model group (P<0.05). In comparison with the model group, MIRI-induced increases of LVEDP, TNF-α and IL-6 contents, and FXR, SHP and AIF mRNA expression and decreases of ±dp/dtmax and LVSP levels were reversed(P<0.05), except HSP70 mRNA expression with significantly increased (P<0.05) in the EA pretreatment group. CONCLUSION: EA pretreatment can protect the left ventricular function of the ischemic heart in MIRI rats, which may be related to its effects in reliving peripheral inflammation and regulating the expression levels of apoptosis-related factors FXR, SHP, AIF and HSP70 in the myocardium.

[Effect of electroacupuncture pretreatment on hippocampal oxidative stress in aged mice with postoperative cognitive dysfunction].

OBJECTIVE: To observe the effect of electroacupuncture (EA) pretreatment on hippocampal oxidative stress in aged mice with postoperative cognitive dysfunction (POCD) and explore the relevant mechanism of EA pretreatment on the improvement of learning and memory in POCD aged mice. METHODS: A total of 72 healthy male aged mice were randomized into a blank group, a model group, a medication group and an EA group, 18 mice in each one. In each group, 1-day, 3-day and 7-day subgroups were divided separately, 6 mice in each subgroup. In the EA group, "Baihui" (GV 20) and "Dazhui" (GV 14) were selected and stimulated with EA, using continuous wave (15 Hz, 1 mA), continuously for 30 min, once a day, for 5 days consecutively. In the medication group, 10% minocycline was injected intraperitoneally, 40 mg/kg, once a day, consecutively for 5 days. In the blank and the control group, intraperitoneal injection of 0.9% sodium chloride solution was given with equal dosage. Except the blank group, at the end of intervention, partial hepatectomy was conducted to establish POCD model in the rest groups. Morris water maze test was adopted to evaluate the learning and memory ability of the aged mice. ELISA was used to determine the contents of reactive oxygen species (ROS) and malondialdehyde (MDA) in the hippocampal tissue. Western blot method was applied to detect the protein expressions of superoxide dismutase 1 (SOD 1) and superoxide dismutase 2 (SOD 2) in the hippocampal tissue. RESULTS: Compared with the blank group, the percentage of platform quadrant residence time was obviously reduced in the mice in the model group (P<0.01), and those in the medication group and the EA group were larger than the model group (P<0.01). Compared with the model group, the contents of ROS were reduced in each subgroup of the medication group and the 3-day subgroup and the 7-day subgroup of the EA group separately (P<0.01, P<0.05), MDA contents were reduced in the medication group and the EA group (P<0.01, P<0.05), the protein expressions of SOD 1 and SOD 2 were all increased in each subgroup of the medication group and the 3-day subgroup and the 7-day subgroup of the EA group (P<0.05, P<0.01). Compared with the medication group, the contents of ROS and MDA in the 1-day subgroup of the EA group were increased (P<0.05), the hippocampal SOD 1 protein expression was increased in the 7-day group of the EA group (P<0.05) and the hippocampal SOD 2 protein expression was reduced in the 1-day subgroup of the EA group (P<0.05). CONCLUSION: Electroacupuncture pretreatment at "Baihui" (GV 20) and "Dazhui" (GV 14) may increase the learning and memory ability of POCD aged mice, which is probably related to the decrease of oxidative stress and the strengthening of hippocampal antioxidant capacity.

[Effect of electroacupuncture pretreatment on transient receptor potential vanilloid 1(TRPV1)/calcitonin gene-related peptide(CGRP) signal and NF-κB p65 protein expression in rats with acute myocardial ischemia].

OBJECTIVE: To observe the effect of electroacupuncture(EA)pretreatment on transient receptor potential vanilloid 1(TRPV1)/calcitonin gene-related peptide(CGRP)signal and nuclear factor-κB p65 (NF-κB p65) protein expression in myocardial tissue of acute myocardial ischemic injury (AMI) rats, and to investigate the possible mechanism of electroacupuncture pretreatment against AMI. METHODS: A total of 60 adult male SD rats were randomly divided into blank control, sham operation, model and EA pretreatment groups, 15 rats in each group. The acute myocardial ischemia model was established by ligating the left anterior descending (LAD)branch of the coronary artery in the model group and EA pretreatment group, while threading but no ligating at left anterior descending branch of the coronary artery was applied in the sham operation group. In the EA pretreatment group, bilateral "Neiguan"(PC6) acupoints were selected, with intensity of 2 mA and frequency of 2 Hz/100 Hz, for 20 min, once daily for 7 days before modeling. Electrocardiogram (ECG) was recorded by physiological signal acquisition system, and the ST segment potential offset values of standard Ⅱ lead were analyzed before surgery，30 min and 24 h after operation. The TTC staining was used to observe the percentage of myocardial infarction area. The HE staining was used to observe the pathological changes of myocardial tissue and the degree of inflammatory cell infiltration. And Western blot was used to detect TRPV1/CGRP signal and NF-κB p65 protein expression levels in myocardial tissue. RESULTS: Compared with the sham operation group, the ECG-J point potential in the model group was significantly increased at 30 min and decreased at 24 h after operation (P<0.05), myocardial infarction area increased significantly (P<0.05), the myocardial fibers were obviously disordered, inflammatory cell infiltration was obvious, and the expressions of TRPV1，CGRP and NF-κB p65 proteins were all increased (P<0.05). Compared with the model group, the EA pretreatment group was decreased in the ECG-J point potential at 30 min after operation(P<0.05), significantly reduced in myocardial infarction area (P<0.05), improved in the morphology of myocardial fibers, reduced ininflammatory cell infiltration, and increased in the protein expressions of TRPV1 and CGRP in myocardium (P<0.05), significantly decreased in the protein expression of NF-κB p65 (P<0.05). CONCLUSION: EA pretreatment may enhance TRPV1/CGRP signaling, down-regulate NF-κB p65 protein expression, reduce myocardial inflammatory response status, improve AMI injury, and reduce myocardial infarction area.

Electroacupuncture pretreatment promotes angiogenesis via hypoxia-inducible factor 1α and vascular endothelial growth factor in a rat model of chronic myocardial ischemia.

OBJECTIVE: Electroacupuncture (EA) pretreatment appears useful in the treatment of chronic myocardial ischemia (CMI). The goal of this study was to investigate the effect of EA preconditioning on the regulation of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) proteins in a CMI model of vascular regeneration. METHODS: A CMI model was established by subcutaneous injection of isoprinosine hydrochloride (ISO) for 14 days in 45 Wistar rats, which had been randomly divided into a model group (n = 15), a CMI group pretreated with sham EA for 21 days (CMI + Sham group, n = 15) and a CMI group pretreated with verum EA for 21 days (CMI + EA, n = 15) prior to modeling. An additional 15 Wistar rats received 0.9% sodium chloride via intraperitoneal injection for 14 consecutive days (control group). Serum levels of VEGF and HIF-1α were measured by ELISA, while protein expression of VEGF and HIF-1α in the area of myocardial infarction was measured by Western blotting. The area of myocardial infarction and fibrosis of the myocardial tissue in the study groups were visualized by hematoxylin-eosin (HE) staining and Masson staining, respectively. RESULTS: EA pretreatment improved cardiac function by regulating left ventricular end-diastolic diameter and left ventricular end-systolic diameter, left ventricular ejection fraction and the ST segment voltage of the electrocardiogram. EA pretreatment promoted vascular regeneration by increasing serum levels of VEGF and HIF-1α and by increasing protein expression of HIF-1α and VEGF in the infarcted region of the myocardium, leading to a reduction in the area of myocardial infarction on HE staining and reduction of myocardial fibrosis on Masson staining. CONCLUSION: EA pretreatment promotes protein expression of HIF-1α and VEGF in areas of ischemic myocardium, which may represent useful biomarkers for coronary collateral establishment and offer potential targets for therapeutic angiogenesis in patients with CMI.

Effect of electroacupuncture pretreatment on hippocampal oxidative stress in aged mice with postoperative cognitive dysfunction / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) pretreatment on hippocampal oxidative stress in aged mice with postoperative cognitive dysfunction (POCD) and explore the relevant mechanism of EA pretreatment on the improvement of learning and memory in POCD aged mice.@*METHODS@#A total of 72 healthy male aged mice were randomized into a blank group, a model group, a medication group and an EA group, 18 mice in each one. In each group, 1-day, 3-day and 7-day subgroups were divided separately, 6 mice in each subgroup. In the EA group, "Baihui" (GV 20) and "Dazhui" (GV 14) were selected and stimulated with EA, using continuous wave (15 Hz, 1 mA), continuously for 30 min, once a day, for 5 days consecutively. In the medication group, 10% minocycline was injected intraperitoneally, 40 mg/kg, once a day, consecutively for 5 days. In the blank and the control group, intraperitoneal injection of 0.9% sodium chloride solution was given with equal dosage. Except the blank group, at the end of intervention, partial hepatectomy was conducted to establish POCD model in the rest groups. Morris water maze test was adopted to evaluate the learning and memory ability of the aged mice. ELISA was used to determine the contents of reactive oxygen species (ROS) and malondialdehyde (MDA) in the hippocampal tissue. Western blot method was applied to detect the protein expressions of superoxide dismutase 1 (SOD 1) and superoxide dismutase 2 (SOD 2) in the hippocampal tissue.@*RESULTS@#Compared with the blank group, the percentage of platform quadrant residence time was obviously reduced in the mice in the model group (@*CONCLUSION@#Electroacupuncture pretreatment at "Baihui" (GV 20) and "Dazhui" (GV 14) may increase the learning and memory ability of POCD aged mice, which is probably related to the decrease of oxidative stress and the strengthening of hippocampal antioxidant capacity.

[Electroacupuncture and moxibustion pretreatments reduce cardiomyocyte apoptosis and autophagy in rats with myocardial ischemia/reperfusion injury].

OBJECTIVE: To observe the effect of "Neiguan" (PC6)-electroacupuncture (EA) or moxibustion (Moxi) pretreatment on myocardial apoptosis and expression of autophagy related proteins light chain (LC) 3-Ⅰ and LC3-Ⅱ in rats with myocardial ischemia/reperfusion injury (MIRI), so as to explore their mechanisms underlying improvement of MIRI. METHODS: Forty SD rats (half male and half female) were randomly divided into sham operation, model, ischemic preconditioning (IP), EA and Moxi groups (n＝8 in each group). EA (10 Hz/50 Hz, 1 mA) or Moxi (ignited moxa stick) was respectively applied to bilateral "Neiguan" (PC6) for 20 min, once daily for 7 days. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min. The ultrastructural changes and autophagy of myocardial cells were observed by electron microscopy (EM), and the myocardial cellular apoptosis [apoptotic index ＝ (number of apoptotic cells/total number of cardiomyocytes)×100%] was detected by the terminal deoxyribonucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method. The expressions of LC3-Ⅰ and LC3-Ⅱ proteins (markers for autophagy) in myocardial tissue were detected by Western blot. RESULTS: Following MI, EM observation revealed a vague structure of cardiomyocytes and muscular horizontal grain, dissolution of myofibers, mitochondrial swelling, some autophagic vacuoles and autophagic lysosomes at different degrees and surrounded by a double membrane in the model group, these situations were apparently milder in the EA and Moxi groups. The apoptosis index, myocardial LC3-Ⅰ and LC3-Ⅱ protein expression levels, and the ratio of LC3-Ⅱ/Ⅰ were significantly increased in the model group relevant to the sham operation group (P<0.05). After the treatment, the apoptosis index, the expression level of myocardial LC3-Ⅱ protein and the ratio of LC3-Ⅱ/Ⅰ were considerably down-regulated in the IP, EA and Moxi groups in comparison with those in the model group (P<0.05). The effect of EA was obviously superior to those of IP and Moxi in down-regulating the apoptosis index (P<0.05), but obviously inferior to those of IP and Moxi in down-regulating the levels of LC3-Ⅱ and LC3-Ⅱ/Ⅰ (P<0.05). No significant changes were found in the expression of LC3-Ⅰ after IP, EA and Moxi interventions in comparison with the model group (P>0.05), and no significant differences were observed in the apoptosis index and levels of LC3-Ⅱ and LC3-Ⅱ/Ⅰ between the IP and Moxi groups (P>0.05)．. CONCLUSION: Both EA and moxibustion pretreatments, similar to IP, have a positive role in reducing myocardiocyte apoptosis and regulating autophagy-related protein expression in MIRI rats, which maybe contribute to their protective effects on ischemic myocardium.

Electroacupuncture and moxibustion pretreatments reduce cardiomyocyte apoptosis and autophagy in rats with myocardial ischemia/reperfusion injury / 针刺研究

OBJECTIVE: To observe the effect of "Neiguan" (PC6)-electroacupuncture (EA) or moxibustion (Moxi) pretreatment on myocardial apoptosis and expression of autophagy related proteins light chain (LC) 3-Ⅰ and LC3-Ⅱ in rats with myocardial ischemia/reperfusion injury (MIRI), so as to explore their mechanisms underlying improvement of MIRI. METHODS: Forty SD rats (half male and half female) were randomly divided into sham operation, model, ischemic preconditioning (IP), EA and Moxi groups (n＝8 in each group). EA (10 Hz/50 Hz, 1 mA) or Moxi (ignited moxa stick) was respectively applied to bilateral "Neiguan" (PC6) for 20 min, once daily for 7 days. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min. The ultrastructural changes and autophagy of myocardial cells were observed by electron microscopy (EM), and the myocardial cellular apoptosis [apoptotic index ＝ (number of apoptotic cells/total number of cardiomyocytes)×100%] was detected by the terminal deoxyribonucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method. The expressions of LC3-Ⅰ and LC3-Ⅱ proteins (markers for autophagy) in myocardial tissue were detected by Western blot. RESULTS: Following MI, EM observation revealed a vague structure of cardiomyocytes and muscular horizontal grain, dissolution of myofibers, mitochondrial swelling, some autophagic vacuoles and autophagic lysosomes at different degrees and surrounded by a double membrane in the model group, these situations were apparently milder in the EA and Moxi groups. The apoptosis index, myocardial LC3-Ⅰ and LC3-Ⅱ protein expression levels, and the ratio of LC3-Ⅱ/Ⅰ were significantly increased in the model group relevant to the sham operation group (P0.05), and no significant differences were observed in the apoptosis index and levels of LC3-Ⅱ and LC3-Ⅱ/Ⅰ between the IP and Moxi groups (P>0.05)．. CONCLUSION: Both EA and moxibustion pretreatments, similar to IP, have a positive role in reducing myocardiocyte apoptosis and regulating autophagy-related protein expression in MIRI rats, which maybe contribute to their protective effects on ischemic myocardium.

[Effect of Electroacupuncture and Moxibustion Pretreatment on Expression of Autophagy Related Proteins LC 3 and Beclin 1 in Rats with Myocardial Ischemia-reperfusion Injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) and moxibustion (Moxi) pretreatment on myocardial pathological and structural changes and expression of autophagy related protein LC 3 Ⅰ/Ⅱ and Beclin 1 in rats with myocardial ischemia-reperfusion injury (MI/RI), so as to explore their mechanisms underlying improving MI/RI. METHODS: Forty SD rats were randomly divided into sham operation, model, ischemic preconditioning (IP), EA and Moxi groups (n＝8 in each group). EA (10 Hz/50 Hz，1 mA) or Moxi (ignited moxa stick) was respectively applied to bilateral "Neiguan"(PC 6) for 20 min, once daily for 7 days. The MI/RI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min. The left ventricular (LV) tissue samples were collected and analyzed for pathological (H.E. staining) and ultrastructural changes, for myocardial apoptosis (apoptotic index＝ number of apoptotic cells/total number of cardiomyocytes×100%) with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method, and for the expression of LC 3 and Beclin 1 in myocardial cells with Western blot. RESULTS: Following MI/RI, H．E. staining revealed a disorder of arrangement of cardiomyocytes with vague border, inflammatory cell infiltration, intracellular swelling with bleeding, necrosis and dissolution of partial striated muscles of the left ventricle under light microscope, and dual staining of Uranyl acetate and leadnitrate showed atrophy, arrangement disorder, dissolution, necrosis, and interstitial edema of partial myocardial fibers, mitochondrial structural disorder, vacolation, and large body of autophagosomes with bilayers, etc. in ultrastructure, which was relatively lighter in both EA and Moxi groups. The apoptosis index, expression levels of myocardial LC 3 Ⅱ and Beclin 1 and the ratio of LC 3 Ⅱ/LC 3 Ⅰ were significantly higher in the model group than those in the sham operation group (P<0.01), but the expression level of LC 3 Ⅰ was considerably down-regulated in the model group relevant to the sham operation group (P<0.01). Following the intervention and MI preconditioning, the increased apoptosis index and expression levels of LC 3Ⅱ and Beclin 1 proteins and the ratio of LC 3Ⅱ/LC 3 Ⅰ were obviously down-regulated in the IP, EA and Moxi groups relevant to the model group (P<0.01), and the decreased expression of LC 3 Ⅰ protein was up-regulated obviously in the 3 treatment groups (P<0.05，P<0.01). The effects of EA were significantly superior to those of IP and Moxi groups in down-regulating apoptosis index and expression of LC 3 Ⅱ and Beclin 1 and the ratio of LC 3 Ⅱ/LC 3 Ⅰ and in up-regulating expression of LC 3 Ⅰ (P<0.05, P<0.01). CONCLUSION: Both EA and Moxi preconditioning of PC 6 have a protective effect on ischemic myocardium in MI/RI rats, which is probably related to their effects in regulating expression of myocardial autophagy proteins as LC 3 Ⅰ/Ⅱ and Beclin 1.

Effect of Electroacupuncture and Moxibustion Pretreatment on Expression of Autophagy Related Proteins LC 3 and Beclin 1 in Rats with Myocardial Ischemia-reperfusion Injury / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) and moxibustion (Moxi) pretreatment on myocardial pathological and structural changes and expression of autophagy related protein LC 3 Ⅰ/Ⅱ and Beclin 1 in rats with myocardial ischemia-reperfusion injury (MI/RI), so as to explore their mechanisms underlying improving MI/RI. METHODS: Forty SD rats were randomly divided into sham operation, model, ischemic preconditioning (IP), EA and Moxi groups (n＝8 in each group). EA (10 Hz/50 Hz，1 mA) or Moxi (ignited moxa stick) was respectively applied to bilateral "Neiguan"(PC 6) for 20 min, once daily for 7 days. The MI/RI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min. The left ventricular (LV) tissue samples were collected and analyzed for pathological (H.E. staining) and ultrastructural changes, for myocardial apoptosis (apoptotic index＝ number of apoptotic cells/total number of cardiomyocytes×100%) with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method, and for the expression of LC 3 and Beclin 1 in myocardial cells with Western blot. RESULTS: Following MI/RI, H．E. staining revealed a disorder of arrangement of cardiomyocytes with vague border, inflammatory cell infiltration, intracellular swelling with bleeding, necrosis and dissolution of partial striated muscles of the left ventricle under light microscope, and dual staining of Uranyl acetate and leadnitrate showed atrophy, arrangement disorder, dissolution, necrosis, and interstitial edema of partial myocardial fibers, mitochondrial structural disorder, vacolation, and large body of autophagosomes with bilayers, etc. in ultrastructure, which was relatively lighter in both EA and Moxi groups. The apoptosis index, expression levels of myocardial LC 3 Ⅱ and Beclin 1 and the ratio of LC 3 Ⅱ/LC 3 Ⅰ were significantly higher in the model group than those in the sham operation group (P<0.01), but the expression level of LC 3 Ⅰ was considerably down-regulated in the model group relevant to the sham operation group (P<0.01). Following the intervention and MI preconditioning, the increased apoptosis index and expression levels of LC 3Ⅱ and Beclin 1 proteins and the ratio of LC 3Ⅱ/LC 3 Ⅰ were obviously down-regulated in the IP, EA and Moxi groups relevant to the model group (P<0.01), and the decreased expression of LC 3 Ⅰ protein was up-regulated obviously in the 3 treatment groups (P<0.05，P<0.01). The effects of EA were significantly superior to those of IP and Moxi groups in down-regulating apoptosis index and expression of LC 3 Ⅱ and Beclin 1 and the ratio of LC 3 Ⅱ/LC 3 Ⅰ and in up-regulating expression of LC 3 Ⅰ (P<0.05, P<0.01). CONCLUSION: Both EA and Moxi preconditioning of PC 6 have a protective effect on ischemic myocardium in MI/RI rats, which is probably related to their effects in regulating expression of myocardial autophagy proteins as LC 3 Ⅰ/Ⅱ and Beclin 1.