PURPOSE: Adipose-derived stem cells (ADSCs) are known to be potentially effective in regeneration of damaged tissue. We aimed to assess the effectiveness of intracoronary administration of ADSCs in reducing the infarction area and improving function after acute transmural myocardial infarction (MI) in a porcine model. MATERIALS AND METHODS: ADSCs were obtained from each pig's abdominal subcutaneous fat tissue by simple liposuction. After 3 passages of 14-days culture, 2 million ADSCs were injected into the coronary artery 30 min after acute transmural MI. At baseline and 4 weeks after the ADSC injection, 99mTc methoxyisobutylisonitrile-single photon emission computed tomography (MIBISPECT) was performed to evaluate the left ventricular volume, left ventricular ejection fraction (LVEF; %), and perfusion defects as well as the myocardial salvage (%) and salvage index. At 4 weeks, each pig was sacrificed, and the heart was extracted and dissected. Gross and microscopic analyses with specific immunohistochemistry staining were then performed. RESULTS: Analysis showed improvement in the perfusion defect, but not in the LVEF in the ADSC group (n=14), compared with the control group (n=14) (perfusion defect, -13.0+/-10.0 vs. -2.6+/-12.0, p=0.019; LVEF, -8.0+/-15.4 vs. -15.9+/-14.8, p=0.181). There was a tendency of reducing left ventricular volume in ADSC group. The ADSCs identified by stromal cell-derived factor-1 (SDF-1) staining were well co-localized by von Willebrand factor and Troponin T staining. CONCLUSION: Intracoronary injection of cultured ADSCs improved myocardial perfusion in this porcine acute transmural MI model.
Adipose Tissue/cytology ; Animals ; Bone Marrow Cells/cytology/*metabolism ; Chemokine CXCL12 ; Coronary Vessels ; Female ; Heart/physiopathology ; Heart Ventricles ; *Mesenchymal Stromal Cells ; Myocardial Infarction/physiopathology/radionuclide imaging/*therapy ; *Stem Cell Transplantation ; Swine ; Technetium Tc 99m Sestamibi/*pharmacology ; Tomography, Emission-Computed, Single-Photon/*methods ; Troponin T ; *Ventricular Function, Left

To improve a fast and high-quality isolation method for culturing the primary cardiomyocyte and fibroblast in vitro, the neonatal Wistar rats were decapitated accordingly and left ventricles were isolated under the sterile condition. The ventricles were chopped and digested in the enzyme solution containing 0.5 mg/mL type II collagenase. During this process, the digesting time, frequency and stirring speed, centrifuging frequency and speed were strictly controlled. The cardiomyocytes were separated from the cardiac fibroblast by using the Percoll density gradient centrifugation. The cell viability was tested by staining with 0.2% trypan blue. The purity of cardiomyocytes and fibroblasts were determined by immunoflourescent staining with anti-cTnI, anti-Vimentin and anti-α-SMA antibodies. The results indicated that with this protocol, the viability and purity of cardiomyocytes were 92% and 95%. The automobile pulse of the adhered cardiomyocyte was visible. For fibroblasts, the cell viability and purity were 96% and 94%. Our results demonstrate that this advanced isolation method is reproducible, and can simultaneously produce high-quality primary cardiomyocytes and fibroblasts for the future study.
Animals ; Cell Separation ; methods ; Cell Survival ; Centrifugation, Density Gradient ; Fibroblasts ; Heart Ventricles ; cytology ; Myocytes, Cardiac ; Povidone ; Rats ; Rats, Wistar ; Silicon Dioxide

Cellular excitability is an important physiological factor in maintaining normal cardiac activity. The present study was designed to investigate the ionic mechanism underlying different excitability in atrial and ventricular myocytes of guinea pig heart using a whole-cell patch configuration. We found that excitability is lower in ventricular myocytes than that in atrial myocytes. Although the density of voltage-gated fast Na(+) current (INa) was lower in ventricular myocytes, it would not correlate to the lower excitability since its availability was greater than that in atrial myocytes around threshold potential. Classical inward rectifier K(+) current (IK1) was greater in ventricular myocytes than that in atrial myocytes, which might contribute in part to the lower excitability. In addition, the transient outward K(+) current with inward rectification (Itoir) elicited by depolarization was greater in ventricular myocytes than that in atrial myocytes and might contribute to the lower excitability. In ventricular myocytes, Ba(2+) at 5 µmol/L significantly inhibited Itoir, enhanced excitability, and shifted the threshold potential of INa activation to more negative, and the effect was independent of affecting INa. Our results demonstrate the novel information that in addition to classical IK1, Itoir plays a major role in determining the distinctive excitability in guinea pig atrial and ventricular myocytes and maintaining cardiac excitability. More effort is required to investigate whether increase of Itoir would be protective via reducing excitability.
Animals ; Atrial Function ; Guinea Pigs ; Heart Atria ; cytology ; Heart Ventricles ; cytology ; Myocytes, Cardiac ; physiology ; Potassium Channels, Inwardly Rectifying ; physiology ; Ventricular Function ; Voltage-Gated Sodium Channels ; physiology

To study the antiarrhythmic effect of the newly developed alpha/beta-blocker TJ0711, a variety of animal models of arrhythmia were induced by CaCl2, ouabain and ischemia/reperfusion. Glass microelectrode technique was used to observe action potentials of right ventricular papillary muscle of guinea pig. The onset time of arrhythmia induced by CaCl2 was significantly prolonged by TJ0711 at 0.75, 1.5 and 3 mg x kg(-1) doses. TJ0711 (1.5 and 3 mg x kg(-1)) can significantly shorten the ventricular tachycardia (VT) and ventricular fibrillation (VF) duration, the incidence of VF and mortality were significantly reduced. On ischemia-reperfusion-induced arrhythmic model, TJ0711 (0.25, 0.5, 1 and 2 mg x kg(-1)) can significantly reduce the ventricular premature contraction (PVC), VT, VF incidence, mortality, arrhythmia score with a dose-dependent manner. At the same time, rats serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities decreased significantly by TJ0711 (1 and 2 mg x kg(-1)). Ouabain could cause arrhythmia in guinea pigs, when TJ0711 (0.375, 0.75, 1.5 and 3 mg x kg(-1)) was given, the doses of ouabain inducing a variety of arrhythmia PVC, VT, VF, cardiac arrest (CA) were significantly increased with a dose-dependent manner. In the TJ0711 0.1-30 micromol x L(-1) concentration range, guinea pig right ventricular papillary muscle action potential RP (rest potential), APA (action potential amplitude) and V(max) (maximum velocity of depolarization) were not significantly affected. APD20, APD50 and APD90 had a shortening trend but no statistical difference with the increase of TJ0711 concentration. TJ0711 has antiarrhythmic effect on the sympathetic nerve excitement and myocardial cell high calcium animal arrhythmia model. Myocardial action potential zero phase conduction velocity and resting membrane potential were not inhibited by TJ0711. APD20, APD50 and APD90 were shortened by TJ0711 at high concentration. Its antiarrhythmic action mechanism may be besides the action of blocking beta1 receptor, may also have a strong selective blocking action on alpha1 receptor and reducing intracellular calcium concentration.
Action Potentials ; drug effects ; Adrenergic alpha-Antagonists ; administration & dosage ; pharmacology ; Adrenergic beta-Antagonists ; administration & dosage ; pharmacology ; Animals ; Anti-Arrhythmia Agents ; administration & dosage ; pharmacology ; Arrhythmias, Cardiac ; blood ; chemically induced ; etiology ; pathology ; physiopathology ; Calcium Chloride ; Creatine Kinase ; blood ; Dose-Response Relationship, Drug ; Female ; Guinea Pigs ; Heart Ventricles ; cytology ; Lactate Dehydrogenases ; blood ; Male ; Myocardial Reperfusion Injury ; complications ; Myocytes, Cardiac ; drug effects ; physiology ; Ouabain ; Papillary Muscles ; cytology ; Phenoxypropanolamines ; administration & dosage ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

Cardiac extracellular matrix (ECM), generated from the process of decellularization, has been widely considered as an ideal source of biological scaffolds. However, current ECM preparations are generally difficult to be applied to generate cardiac tissue. Our research was aimed to improve decellularization protocols to prepare cardiac ECM slices. Adult murine ventricular tissues were embedded in low melting agarose and cut into 300 μm slices, and then were divided randomly into three groups: normal cardiac tissue, SDS treated group (0.1% SDS) and SDS+Triton X-100 treated group (0.1% SDS+0.5% Triton X-100). Total RNA content and protein content quantification, HE staining and immunostaining were used to evaluate the removal of cell components and preservation of vital ECM components. Furthermore, murine embryonic stem cell-derived cardiomyocytes (mES-CMs) and mouse embryonic fibroblasts (MEFs) were co-cultured with ECM slices to evaluate biocompatibility. The relative residual RNA and protein contents of ECM slices significantly decreased after decellularization. HE staining showed that SDS+Triton X-100 treatment better destroyed cellular structure and removed nuclei of ECM slices, compared with SDS treatment. Immunostaining showed that collagen IV and laminin were better preserved and presented better similarity to original cardiac tissue in ECM slices acquired by SDS+Triton X-100 treatment. However, collagen IV and laminin were significantly decreased and arranged disorderly in SDS treated group. We observed effective survival (≥ 12 days) of MEFs and mES-CMs on ECM slices acquired by SDS+Triton X-100 treatment, and signs of integration, whereas those signs were not found in SDS treated group. We concluded that, compared with traditional SDS method, new combined protocol (SDS+Triton X-100) generated ECM slices with better component and structural preservation, as well as better biocompatibility.
Animals ; Extracellular Matrix ; chemistry ; Heart Ventricles ; cytology ; Mice ; Octoxynol ; Sodium Dodecyl Sulfate ; Tissue Engineering ; methods ; Tissue Scaffolds

As the nonspecific clinical presentation of hypereosinophilic syndrome (HES) may mimic many multisystemic diseases, it often presents as a diagnostic challenge. Herein, we report the case of a 60-year-old man who presented with progressive heart failure symptoms and eosinophilia. Despite extensive diagnostic evaluation, no underlying cause was found. Transthoracic echocardiography revealed a large left ventricular thrombus, which is suggestive of hypereosinophilic cardiac involvement. The patient was started on steroids and responded clinically and haematologically.
Blood Cell Count ; Contrast Media ; chemistry ; Echocardiography ; Eosinophils ; cytology ; Flow Cytometry ; Heart Atria ; pathology ; Heart Diseases ; complications ; diagnostic imaging ; Heart Failure ; complications ; Heart Ventricles ; pathology ; Humans ; Hypereosinophilic Syndrome ; complications ; diagnostic imaging ; Male ; Middle Aged ; Motion ; Steroids ; therapeutic use ; Thrombosis ; complications ; diagnostic imaging ; Treatment Outcome

AIM: To study the effects of crebanine on voltage-gated Na(+) channels in cardiac tissues. METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na(+) current was recorded using the whole cell voltage-clamp technique. RESULTS: Crebanine reversibly inhibited Na(+) current with an IC50 value of 0.283 mmol·L(-1) (95% confidence range: 0.248-0.318 mmol·L(-1)). Crebanine at 0.262 mmol·L(-1) caused a negative shift (about 12 mV) in the voltage-dependence of steady-state inactivation of Na(+) current, and retarded its recovery from inactivation, but did not affect its activation curve. CONCLUSION In addition to blocking other voltage-gated ion channels, crebanine blocked Na(+) channels in guinea-pig ventricular myocytes. Crebanine acted as an inactivation stabilizer of Na(+) channels in cardiac tissues.
Animals ; Aporphines ; pharmacology ; Cells, Cultured ; Down-Regulation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Female ; Guinea Pigs ; Heart Ventricles ; cytology ; drug effects ; metabolism ; Male ; Myocytes, Cardiac ; drug effects ; metabolism ; Stephania ; chemistry ; Voltage-Gated Sodium Channel Blockers ; pharmacology ; Voltage-Gated Sodium Channels ; metabolism

The study aimed to investigate the age-related changes and drug reactions of transient outward potassium current (Ito) of ventricular myocytes. Twenty-eight Sprague Dawley rats were divided into young (3-5 months), adult (13-15 months) and aged (22-24 months) groups, and Ito currents of isolated myocytes from each group were recorded respectively by patch-clamp. The perfusion of 2.0 mmol/L 4-AP or 1.0 μmol/L isoproterenol was added respectively in each group, and the changes of Ito were observed. In comparison with young and adult groups, Ito densities of ventricular myocytes in aged group was significantly increased, the curve of steady-state activation of Ito shifted to the left, the close-state inactivation rate significantly decreased, and recovery rate from the steady-state inactivation became quicker. However, no significant changes could be detected for the Ito steady-state inactivation of ventricular myocytes in aged group. The similar responsiveness to 4-AP was observed in all three groups, but the responsiveness to isoproterenol was weaker in the aged group (55.9%) than in the other two groups (127.5% and 125.8%). In conclusion, the results show that Ito of rat ventricular myocyte of aging heart has increased current density and decreased response to isoproterenol.
4-Aminopyridine ; pharmacology ; Aging ; Animals ; Cells, Cultured ; Heart Ventricles ; cytology ; Isoproterenol ; pharmacology ; Myocytes, Cardiac ; physiology ; Potassium Channels ; physiology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo observe the changes of surface ECG and cell couplings between sinoatrial node cells and myocardial cells following transplantion of pedicled autologous sinoatrial node tissue graft into the right ventricle of a canine model of complete atrioventricular block.

METHODSTen healthy dogs were randomized into transplantation group and control group. Pedicled autologous sinoatrial node tissue grafts were transplanted into the right ventricle in the transplantation group, while the sinoatrial nodes were only excised in the control group after placement of temporary myocardial pacing wires. The changes of surface ECG were observed at 1, 2, 3 and 4 weeks postoperatively. At 4 weeks, complete atrioventricular block was induced in the dogs by radiofrequency ablation of the His bundle. The heart rate of the dogs in both groups were recorded after the injection of isoproternol (ISO) from the femoral vein, and the transplanted tissue graft was observed under optical and transmission electron microscopes.

RESULTSNo significant changes occurred in the surface ECG. All the dogs showed ECG waveforms specific of complete heart block after the ablation, and the ventricular heart rates were similar between the two groups (P>0.05). The ventricular heart rate did not undergo obvious changes after ISO injection (P>0.05). The transplanted pedicled autologous sinoatrial node survived in the dogs and the sinoatrial node cells established desmosome junctions with the myocardial cells, but the number of junctions was not sufficient to support heart pacing.

CONCLUSIONDesmosome junction can occur between ventricular myocardial cells and sinoatrial node cells at the edge of transplanted pedicled autologous sinoatrial node tissue.

Animals ; Atrioventricular Block ; physiopathology ; surgery ; Cardiotonic Agents ; pharmacology ; Dogs ; Electrocardiography ; Female ; Heart Rate ; drug effects ; Heart Ventricles ; surgery ; Intercellular Junctions ; Isoproterenol ; pharmacology ; Male ; Myocardium ; cytology ; Sinoatrial Node ; cytology ; transplantation ; Tissue Transplantation ; Transplantation, Autologous

OBJECTIVE: To investigate the relationship between apoptosis of myocardial cells in spontaneously hypertensive rats (SHRs) and the expressions of Bcl-2 and Bax protein, and the protective effect of stellate ganglion block on apoptosis of myocardial cells. METHODS: A total of 32 ten-week-old male SHRs were assigned randomly into 4 groups: a left stellate ganglion block group (group LS), a right stellate ganglion block group (group RS), a captopril group (group D) and a control group (group C). The arterial systolic blood pressure was measured by ALC-NIBP system. After 10 weeks, all rats were anaesthetized by 3% pentobarbital sodium, cardiomyocyte apoptosis index of left ventricle was assessed by TUNEL, and the localization of myocardium Bcl-2, Bax was investigated by immunohistochemistry. RESULTS: Compared with group LS and C, the apoptotic index decreased (P<0.05). SHR myocardial expression of Bcl-2 significantly increased (P<0.05), Bax expression significantly decreased (P<0.05) and Bcl-2/Bax was significantly higher (P<0. 05) in group RS. CONCLUSION Bcl-2 and Bax play an important role in the apoptosis of myocardial cells in SHRs. Right stellate ganglion block can reduce the apoptosis of myocardial cells and reverse the reconstruction of the left ventricle in SHRs via regulation of apoptosis-related gene proteins.
Animals ; Apoptosis ; Autonomic Nerve Block ; Blood Pressure ; Heart Ventricles ; Male ; Myocardium ; Myocytes, Cardiac ; cytology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Inbred SHR ; Stellate Ganglion ; physiopathology ; bcl-2-Associated X Protein ; metabolism