OBJECTIVES: To clarify the role of hippocampal glutamate system in regulating HPA axis in mediating the effect of electroacupuncture (EA) at the heart meridian for improving myocardial injury in rats with acute myocardial ischemia (AMI). METHODS: Male SD rats were randomized into sham-operated group, AMI group, EA group, and L-glutamic acid+EA group (n=9). Rat models of AMI were established by left descending coronary artery ligation, and EA was applied at the "Shenmen-Tongli" segment; the rats in L-glutamic acid+EA group were subjected to microinjection of L-glutamic acid into the bilateral hippocampus prior to AMI modeling and EA treatment. Cardiac functions of the rats were evaluated using echocardiography, and ECG and heart rate variation (HRV) were analyzed using PowerLab and LabChart. Pathological changes in the myocardial tissue was examined using HE staining, and serum levels of myocardial enzymes were detected with ELISA. Myocardial expressions of TH and GAP43 were detected with immunohistochemistry, and colocalization of VGLUT1, VGLUT2 and c-fos were observed using immunofluorescence staining; the expressions of VGLUT1, VGLUT2, NMDAR1 and NMDAR2B were detected using Western blotting. RESULTS: The rat models of AMI showed significantly decreased LVEF and LVFS and increased serum levels of myocardial enzymes in positive correlation with the HPA axis. Numerous TH- and GAP43-positive cells were observed in the hippocampus, where the expressions of NE and E, neurons colabeled with VGLUT1, VGLUT2 and c-fos, and expressions of VGLUT1, VGLUT2, NMDAR1, NMDAR2B and Glu increased significantly. All these changes were significantly improved by interventions with EA as compared with those in AMI and L-Glutamate+EA groups. CONCLUSIONS In rats with AMI, EA at the heart meridian can regulate excessive glutamate release in the hippocampus, thereby inhibiting HPA axis hyperactivity and reducing sympathetic nerve activity to protect the myocardial tissue.
Animals ; Electroacupuncture ; Male ; Rats, Sprague-Dawley ; Hippocampus/metabolism* ; Rats ; Glutamic Acid/metabolism* ; Myocardial Ischemia/physiopathology* ; Hypothalamo-Hypophyseal System/physiopathology* ; Pituitary-Adrenal System/physiopathology* ; Receptors, N-Methyl-D-Aspartate/metabolism*

OBJECTIVETo observe the effects of electroacupuncture (EA) at different acupoints on apoptosis-related serum and expression of microRNA (miRNA) in rats with myocardial ischemia, so as to explore its mechanism of action.

METHODSA total of 48 male Wistar rats were randomly divided into a normal group, a model group, a Neiguan group and a acupoint compatibility group, 12 rats in each group. Isoprenaline hydrochloride (ISO) with a daily dose of 2 mg/kg was subcutaneously injected for 14 days to establish the myocardial ischemia model in the model group, Neiguan group and acupoint compatibility group. Rats in the normal group were subcutaneously injected with an equal volume of normal saline. After modeling, rats in the Neiguan group were treated with EA at "Neiguan" (PC 6), while rats in the acupoint compatibility group were treated with EA at "Guanyuan" (CV 4), "Zusanli" (ST 36) and "Neiguan" (PC 6). Rats in the normal group and model group were treated with immobilization, once day for 21 days. The contents of creatine kinase-MB (CK-MB), vascular cell adhesion molecule-1 (VCAM-1) and endothelin-1 (ET-1) in serum were detected by enzyme-linked immunosorbent assay (ELISA); apoptosis index (AI) of myocardial cells was detected by TUNEL method; the expressions of miRNA-1, miRNA-133, miRNA-208 and miRNA-499 were detected by real-time PCR method.

RESULTSCompared with the normal group, the serum CK-MB, VCAM-1 and ET-1 were significantly increased in the model group, Neiguan group and acupoint compatibility group (all P < 0.01), and the apoptosis index was significantly increased (all P < 0.01). The CK-MB, VCAM-1 and ET-1 in the Neiguan group and acupoint compatibility group were significantly lower than those in the model group (all P < 0.01); the AI was reduced, which was more significant in the acupoint compatibility group (P < 0.05). Compared with the normal group, the expression of miRNA-133 was reduced (P < 0.01) and those of miRNA-208, miRNA-1 and miRNA-499 were significantly increased in the model group (all P < 0.01). Compared with the model group, the expression of miRNA-133 was increased (both P < 0.01) and that of miRNA-208, miRNA-1 and miRNA-499 were significantly reduced (all P < 0.01) in the Neiguan group and acupoint compatibility group. Compared with the Neiguan group, the expression of miRNA-133 was increased (P < 0.01) and those of miRNA-208, miRNA-1 and miRNA-499 were significantly reduced in the acupoint compatibility group (P < 0.01, P < 0.05).

CONCLUSIONEA at acupoints, especially acupoint compatibility group, could effectively prevent and treat myocardial ischemia, and the protective effect is possibly correlated to the double regulation on increasing the expression of miRNA-133 and inhibiting the expression of miRNA-1, miRNA-208, miRNA-499.

Acupuncture Points ; Animals ; Apoptosis ; Disease Models, Animal ; Electroacupuncture ; Endothelin-1 ; genetics ; metabolism ; Humans ; Male ; MicroRNAs ; genetics ; metabolism ; Myocardial Ischemia ; genetics ; metabolism ; physiopathology ; therapy ; Myocytes, Cardiac ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo explore the effects of principal-subordinate acupoints combination on improving myocardial ischemia, and the gene regulatory pathways for the protection of myocardial ischemia.

METHODSAccording to the random number table method, 70 SPF Wistar male rats were divided into a normal group, a model group, a LY294002 group, an insulin-like growth factors-1(IGF-1) group, a Neiguan group, an acupoint combination group and an acupoint combination + LY294002 group, 10 rats in each one. Rats in the normal group were injected with 0.9% NaCl solution, while rats in the remaining groups were treated with abdominal subcutaneous injection of isoroterenol hydrochloride to establish the rat model of myocardial ischemia. Rats in the LY294002 group and IGF-1 group were treated with injection of LY294002 solution and IGF-1 solution for 14 days. Rats in the Neiguan group were treated with electroacupuncture (EA) at "Neiguan" (PC 6) by using Han-200 EA apparatus for 10 min per treatment. Rats in the acupoint combination group were treated with EA at "Neiguan" (PC 6), "Zusanli" (ST 36) and "Guanyuan" (CV 4) by using Han-200 EA apparatus for 10 min per treatment. Rats in the acupoint combination + LY294002 group were treated with LY294002 solution for 14 days, and EA at "Neiguan" (PC 6), "Zusanli" (ST 36) and "Guanyuan" (CV 4) was given before model establishment, once a day for 21 days. EA pretreatment was given before model establishment in all acupuncture groups. The heart rate (HR) and ST segment voltage were detected before and after treatment; the myocardial pathological morphology was observed by HE staining; the expressions of P13K mRNA and Akt mRNA were tested.

RESULTSAfter modeling, HR and ST segment voltage in all intervention groups were higher than those in the normal group (all P < 0.01); after the intervention, the HR and the ST segment voltage in the acupoint combination group, IGF-1 group and IGF-1 group were improved (P < 0.01, P < 0.05), which was more significant in the acupoint combination group and Neiguan group (all P < 0.01). As for the myocardial pathological morphology, obvious myocardial ischemia was observed in the model group, and that in the LY294002 group was the most serious, and that in the acupoint combination+ LY294002 group was moderate. After intervention, the myocardial pathological damage in the IGF-1 group, Neiguan group and acupoint combination group was significant improved, which was more significant in the IGF-1 group and acupoint combination group. As for the expression of PI3K mRNA and Akt mRNA, compared with normal group, the expression of PI3K mRNA was increased in the remaining groups after modeling (P < 0.01, P < 0.05), which was more significant in the IGF-1 group and acupoint combination group (all P < 0. 01). The expression of Akt mRNA in the LY294002 group and acupoint combination + LY294002 group was reduced (P < 0. 01, P < 0.05), while that in the remaining groups was increased (P < 0.01, P < 0.05), which was more significant in the IGF-1 group and acupoint combination group (all P < 0.01).

CONCLUSIONThe principal-subordinate acupoints combination could improve heart rate and ST segment voltage in rats with chronic myocardial ischemia, reduce myocardial pathological damage, which is superior to single selection of "Neiguan" (PC 6). The PI3K/Akt signaling pathway may be involved in the regulation mechanism of principal-subordinate acupoints combination for the protection of chronic myocardial ischemia.

Acupuncture Points ; Acupuncture Therapy ; Animals ; Chronic Disease ; therapy ; Electroacupuncture ; Electrocardiography ; Heart Rate ; Humans ; Insulin-Like Growth Factor I ; metabolism ; Male ; Myocardial Ischemia ; enzymology ; pathology ; physiopathology ; therapy ; Myocardium ; pathology ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Rats ; Rats, Wistar

To discuss the protective effect of aralosides (AS) on I/R-induced rat myocardial injury. The adult rat ventricular myocyte ischemia model was established through perfusion with sodium lactate perfusate and reperfusion with Ca(2+) -containing Tyrode's solution simulation. The cell contraction and ion concentration synchronization determination system was applied to detect the effect of AS on single I/R cell contraction and Ca2+ transients. According to the findings, AS could increase resting sarcomere length, contraction amplitude, ± dL/dt(max), calcium transient amplitude and speed of post-reperfusion myocardial cells (P < 0.05, P < 0.01), and decrease in time for achieving 90.0% of maximum relaxation, time for achieving peak value, resting calcium ratio, contraction period [Ca2+] i, time for achieving 50.0% of maximum relaxation and attenuation rate of intracellular calcium transient (P < 0.05, P < 0.01). Therefore, it is suggested that AS improved the post-reperfusion cell contraction and injury of calcium homeostasis.
Animals ; Aralia ; chemistry ; Biological Transport ; drug effects ; Calcium ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Male ; Muscle Contraction ; drug effects ; Myocardial Ischemia ; drug therapy ; metabolism ; physiopathology ; surgery ; Myocardial Reperfusion ; Myocytes, Cardiac ; drug effects ; physiology ; Rats ; Rats, Sprague-Dawley ; Saponins ; administration & dosage

To study the therapeutic effect and possible mechanism of icariin on myocardial ischemia-reperfusion injury ( MIRI) model in diabetes rats. The model of diabetic rats were induced by Streptozotocin (STZ), then the model of MIRI was established by ligating the reversible left anterior descending coronary artery for 30 min, and then reperfusing for 120 min. totally 40 male SD were randomly divided into five groups: the control group (NS), the ischemia reperfusion group (NIR), the diabetes control group (MS), the diabetic ischemia reperfusion group (MIR) and the diabetic ischemia reperfusion with icariin group (MIRI). The changes in blood glucose, body weight and living status were observed; the enzyme activity of serum CK-MB, LDH, GSH-Px and myocardium SOD and the content MDA and NO in myocardium were detected; the myocardial pathological changes were observed by HE staining; the myocardial Caspase-3, the Bcl-2, Bax protein expressions were detected by Western blot. The result showed that the diabetes model was successfully replicated; myocardial ischemia-reperfusion injury was more serious in diabetes rats; icariin can increase NO, SOD, GSH-Px, Bcl-2 protein expression, decrease MDA formation, CK-MB and LDH activities and Caspase-3 and Bcl-2 protein expressions and myocardial damage. The result suggested that icariin may play a protective role against ischemia reperfusion myocardial injury in diabetes rats by resisting oxidative stress and inhibiting cell apoptosis.
Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Creatine Kinase ; metabolism ; Diabetes Mellitus, Type 2 ; complications ; Drugs, Chinese Herbal ; administration & dosage ; Flavonoids ; administration & dosage ; Humans ; Ischemia ; drug therapy ; etiology ; physiopathology ; Male ; Malondialdehyde ; metabolism ; Myocardial Reperfusion Injury ; drug therapy ; etiology ; metabolism ; physiopathology ; Myocardium ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo investigate the regulatory effects of Shenfu Injection (SFI, ) on hemodynamic parameters and serum proteins in rats with post-infarction chronic heart failure (CHF).

METHODSForty-five healthy Wistar rats were randomized into three groups: sham, heart failure (model) and SFI group. The CHF was induced by left coronary artery ligation. Seven days after the surgical operation, animals in the sham group and the model group received saline (6.2 mL/kg/d), while animals in the SFI group received SFI (6.2 mL/kg d) intraperitoneally. Four weeks later, cardiac hemodynamic parameters were measured via the carotid route. The expression of serum proteins was analyzed by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS).

RESULTSRecording of hemodynamic parameters showed that left ventricular systolic pressure (LVSP), maximum rate of left ventricular pressure (+dp/dtmax) rise, and maximum rate of left ventricular pressure (-dp/dtmax) decrease, while the left ventricular end diastolic pressure (LVEDP) rose in the model group compared to those in the sham group (P <0.05). The results of the MALDI-TOF MS indicated that haptoglobin (HP), pentraxin 3 (PTX3) and alpha-1-antitrypsin were up-regulated, while serum albumin and 40S ribosomal protein were down-regulated in the model group (P <0.05). Compared with the model group, LVSP, +dp/dtmax and -dp/dtmax were higher, while LVEDP was lower in the SFI group (P<0.05). Expression levels of HP and PTX3 were lower than in the model group (P<0.05).

CONCLUSIONSFI could improve hemodynamic function and decrease inflammatory reactions in the pathophysiology of CHF. The serum proteins HP and PTX3 could be potential biomarkers for chronic ischemic heart failure, and they could also be the serum protein targets of SFI.

Animals ; Blood Proteins ; metabolism ; C-Reactive Protein ; metabolism ; Chronic Disease ; Drugs, Chinese Herbal ; therapeutic use ; Electrophoresis, Gel, Two-Dimensional ; Haptoglobins ; metabolism ; Heart Failure ; blood ; complications ; drug therapy ; physiopathology ; Heart Function Tests ; Hemodynamics ; Hydrogen-Ion Concentration ; Imaging, Three-Dimensional ; Inflammation ; complications ; drug therapy ; Male ; Myocardial Ischemia ; blood ; complications ; drug therapy ; physiopathology ; Phytotherapy ; Proteome ; metabolism ; Rats, Wistar ; Serum Amyloid P-Component ; metabolism ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

OBJECTIVEThe mechanism through which platelet activating factor (PAF) induces cardiac electrical activity and arrhythmia is not well understood and previous studies have suggested a potential involvement of ion channels in its action. The present study was aimed to clarify the role of PAF in fatal arrhythmias following acute myocardia infarction (AMI) and the underlying mechanism.

METHODS(1) Blood PAF levels were measured among 72 AMI patients at the time of diagnosis with AMI and 48 h later, and their electrocardiogram (ECG) was recorded continuously. (2) Ischemia simulation and surface electrocardiogram were conducted in 20 pigs and their PAF levels were measured. (3) PAF perfusion and standard microelectrode recording were performed on guinea pig papillary muscles.

RESULTSIn both humans and pigs, elevated PAF levels were detected in AMI and simulated ischemia, respectively, and even higher PAF levels were found when fatal arrhythmias occurred. In guinea pig myocardium, PAF induced a shortening of action potential duration at 90% level of repolarization (APD90)under non-ischemic conditions and a more pronounced shortening under early simulated ischemic conditions.

CONCLUSIONAMI and ischemia are associated with increased PAF levels in humans and pigs, which are further raised when fatal arrhythmia follows. The effects of PAF on the myocardium may be mediated by multiple ion channels.

Animals ; Arrhythmias, Cardiac ; blood ; etiology ; physiopathology ; Electrocardiography ; Female ; Heart ; physiopathology ; Humans ; Male ; Middle Aged ; Myocardial Ischemia ; blood ; complications ; physiopathology ; Platelet Activating Factor ; metabolism ; Swine

OBJECTIVE: To observe the expression and anti-apoptosis of microRNA-21(miR-21) in rat myocardium during early ischemia-reperfusion injury (I/R). METHODS: Sprague-Dawley rats were randomly divided into 5 groups: a control group (transfected with rAAV9-ZsGreen by coronary injection), a miR-21group (transfected rAAV9-ZsGreen-premiR- 21 by coronary injection), a sham group (open-chest only), an I/R group (I/R), and an I/ R+miR-21 (I/R after transfected rAAV9-ZsGreen-pre-miR-21 by coronary injection). Realtime PCR was used to assess the expression level of miR-21. Immunohistochemistry and Western blot were used to determine the expression of Bcl-2, Bax, caspase-3 and Bcl-2/Bax. RESULTS: MiR-21 was increased by 4.43 times in the miR-21 group (P<0.001). MiR-21 was downregulated in the ischemia zone after I/R compared with the sham group (P<0.05), but that in the non-ischemia zone was significantly increased compared with the sham group (P<0.01). MiR- 21 expression was decreased in the I/R group compared with that in the sham group at 1 h, 2 h and 6 h after I/R (P<0.05), and it was up-regulated in the I/R+miR-21 group at the same time point compared with the I/R group (P<0.01). The expression of Bcl-2, Bax, and caspase-3 was upregulated and Bcl-2/Bax was decreased in the ischemia zone in the I/R group and I/R+miR-21 group than the sham group(P<0.05). Compared with the I/R group, the expression of Bcl-2 and caspase-3 was down-regulated and Bcl-2/Bax was increased in the ischemia zone in the I/ R+miR-21 group (P<0.05). CONCLUSION MiR-21 expression is down-regulated and cell apoptosis is increased in rat myocardium during early ischemia-reperfusion injury. Myocardial cell apoptosis may be alleviated by miR-21 over-expression.
Animals ; Apoptosis ; physiology ; Dependovirus ; genetics ; Genetic Vectors ; Male ; MicroRNAs ; genetics ; metabolism ; Myocardial Ischemia ; physiopathology ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism ; Transfection

Myocardial ischemia and reperfusion (I/R) is a common problem in clinic and there is no satisfactory method for prevention or treatment of I/R injury so far. Chronic intermittent hypobaric hypoxia (CIHH), similar to the concept of ischemia preconditioning (IPC)or altitude hypoxia adaptation (AHA), has been recognized to confer a protective effect on heart against I/R injury with a longer protective effect than IPC and a less adverse effect than AHA. It has been proved that CIHH increases myocardial tolerance to ischemia or hypoxia, reserving cardiac function and preventing arrhythmia during I/R. Multiple mechanisms or pathway underlying the cardiac protection of CIHH have been proposed, such as induction of heat-shock protein, enhancement of myocardial antioxidation capacity, increase of coronary flow and myocardial capillary angiogenesis, activation of adenosine triphosphate (ATP)-sensitive potassium channels, inhibition of mitochondrial permeability transition pores, and activation of protein kinase C (PKC) and induced nitric oxide synthase (iNOS). In addition, CIHH has been found having many beneficial effects on the body, such as promotion of health, increase of oxygen utilization, and prevention or treatment for some diseases. The beneficial effects of CIHH and potential mechanisms are reviewed mainly based on the researches performed by our group.
Adenosine Triphosphate ; metabolism ; Antioxidants ; metabolism ; Heart ; physiopathology ; Heat-Shock Proteins ; metabolism ; Humans ; Hypoxia ; Myocardial Ischemia ; physiopathology ; Myocardium ; pathology ; Nitric Oxide Synthase Type II ; Potassium Channels ; metabolism ; Protein Kinase C ; metabolism ; Reperfusion Injury ; physiopathology

OBJECTIVE: To determine the effect of Gingkgo biloba leaf extract (EGb761) induced delayed preconditioning on cytochrome c oxidase (CcO) expression during myocardial ischemia-reperfusion in rats. METHODS: Four groups (10 in each) of Sprague-Dawley male rats were studied. In the sham group, the rats received no treatment. Rats in the ischemia-reperfusion (IR) group were treated with NS (1.0 mL/kg intravenously) 24 h before ischemia. Rats in the M group were treated with EGb761 (100 mg/kg intravenously) 24 h before the ischemia. In the D group , EGb761-treated rats that received the 5-hydroxydecanoate (5-HD), an inhibitor of mitochondrial KATP channels 15 min before the ischemia. The IR, M, and D groups were subjected to ischemia by 30 min of coronary artery occlusion before 2 h of reperfusion. At the end of the reperfusion, myocardial infarct size was measured. CcO was measured by Western blot. The myocardial ultrastructure was observed under the electron microscope. RESULTS: The infarct size was significantly smaller in the M group [(23.78 ± 4.82)%] than in the I/R group [(37.87 ± 5.92)%] (P<0.05). The CcO protein expression in the myocardium was significantly higher in the M group than in the I/R group(P<0.05). Microscopic examination showed less myocardial damage in the M group than that in the I/R group. The infarct size, CcO protein expression, and myocardial damage had no significant difference between the D group and the I/R group (P>0.05). CONCLUSION EGb761 induced delayed preconditioning attenuates myocardial ischemia-reperfusion injury possibly through up-regulating CcO expression in rats.
Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Electron Transport Complex IV ; metabolism ; Ginkgo biloba ; chemistry ; Ischemic Postconditioning ; methods ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Ischemia ; physiopathology ; Myocardial Reperfusion Injury ; metabolism ; prevention & control ; Phytotherapy ; Plant Leaves ; chemistry ; Rats ; Rats, Sprague-Dawley