Pharmacokinetic study of Polygonum orientale extract in H9c2 cells by UPLC-MS/MS / 中国中药杂志

A detection method of ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) was established to detect concentrations of isoorientin, orientin, quercetin, vitexin and kaempferol-3-O-β-D-glucoside in H9 c2 cells and applied to the pharmacokinetic study of Polygonum orientale extract in the cells. H9 c2 cells were treated with 100 μg·mL~(-1) P. orientale extract and then they and the corresponding nuclei, mitochondria and Golgi bodies were collected at the set time. After protein precipitation, UPLC-MS/MS was used to determine concentrations of isoorientin, orientin, quercetin, vitexin and kaempferol-3-O-β-D-glucoside in the whole cells and subcellular structures. Also, related pharmacokinetic parameters were calculated. The results showed that the peak time was 8 h for all these components. Orientin, vitexin, quercetin and isoorientin have high affinities to nuclei and mitochondria, while the affinity of kaempferol-3-O-β-D-glucoside is higher with mitochondria compared to nuclei. It is suggested that these chemical components of P. orientale may mainly act on nuclei or mitochondria to exert pharmacological effects of protecting cardiomyocytes.

Study on Mechanism of Epigallocatechin Gallate Alleviating Myocardial Ischemia-reperfusion Injury by Inhibiting Cardiomyo- cyte Apoptosis / 中国药房

OBJECTIVE： To investigate the protective effect and potential mechanism of epigallocatechin gallate （EGCG） on myocardial ischemia-reperfusion injury. METHODS： H9C2 cardiomyocytes were treated with tert-butyl hydroperoxide （TBHP） to establish ischemia-reperfusion cell model. The cell viability was measured by MTS after pretreated with different doses of EGCG （3.125， 6.25， 12.5， 25， 50， 100， 200 μmol/L）， and the survival rate was calculated. The expression of apoptotic proteins （Bcl-2， Bax） in cardiomyocytes pretreated with different doses of EGCG （100， 200 μmol/L） were detected by Western blotting. Male C57BL/6 mice were randomly divided into sham operation group， model group and EGCG group （5 mg/g）， with 15 mice in each group. Sham operation group and model group were given constant volume of normal saline intragastrically， while EGCG group was given relevant medicine intragastrically， once a day， for consecutive 7 d. Twelve hours after last medication， myocardial ischemia-reperfusion injury model was established by anterior descending coronary artery ligation. The area of myocardial infarction was observed by double staining of Evan’s blue and TTC； the percentage of infarction area to cross-sectional area was calculated；SOD activity and MDA content in serum were determined by WST-1 assay； the expression of apoptotic proteins （Bcl-2， Bax） in myocardial tissue were detected by Western blotting， while the phosphorylation levels of signaling pathway related proteins （PI3K， p-PI3K， Akt， p-Akt） were also detected. RESULTS： Cell test results showed that， compared with control group， survival rate and relative expression of Bcl-2 were decreased significantly in model group， while relative expression of Bax was increased significantly （P＜0.05）. Compared with model group， survival rate of cardiomyocyte in 25， 50， 100， 200 μmol/L EGCG groups as well as relative expression of Bcl-2 in 100， 200  μmol/L EGCG groups were increased significantly， while relative expression of Bax in 100， 200 μmol/L EGCG groups were decreased significantly （P＜0.05）. Animal experiments showed that no ischemia of myocardial tissue and enlargement of cardiac cavity were observed in sham operation group. Myocardial infarction was observed in model group. Compared with sham operation group， percentage of infarction area to cross-sectional area， the serum content of MDA， the relative expression of Bax in myocardial tissue and p-PI3K/PI3K， p-Akt/Akt were increased significantly in model group， while SOD activity and relative expression of Bcl-2 were decreased significantly （P＜0.05）. Compared with model group， myocardial infarction area of mice in EGCG group was reduced， the percentage of infarction area to cross-sectional area， the serum content of MDA， the relative expression of Bax in myocardial tissue and p-PI3K/PI3K， p-Akt/Akt were significantly decreased， the activity of SOD activity and the relative expression of Bcl-2 were increased significantly （P＜0.05）. CONCLUSIONS： EGCG can protect against myocardial ischemia-reperfusion injury， the mechanism of which may be associated with inhibiting the apoptosis of myocardial cells， improving oxidation stress， regulating the expression of apoptotic protein， reducing the phosphorylation level of PI3K/Akt signaling pathway-related proteins.

Methamphetamine induces autophagy in myocardial cells / 中华急诊医学杂志

Objective To investigate the process of autophagy in myocardial cells induced by methamphetamine (METH).Methods In vivo study:sixty 6-week-old male C57B1/6 J mice were randomly(random number) divided into three groups evenly,control group,three-day METH treated group and seven-day METH treated group.Mice in control group was given physiological saline through intraperitoneal injection 2 times per day and lasted 7 days.Mice in three days group and seven days group intake methamphetamine at a dose of 15 mg/kg every time through intraperitoneal injection 2 times a day,lasted 3 days and 7 days respectively.The hearts of the mice were then obtained by anatomical method 24 hours after the last intraperitoneal injection of METH,then autophagy related proteins were detected by western blotting.In vitro study:the model was established by H9C2 cells.The cells were divided into two groups,control group (cells were cultured by normal medium) and METH group (cells were cultured by medium includes 900 mmol/mL METH for 24 hours).The expressions change of autophagy related proteins in cells were tested by Western blotting.Additionally,LC3-Ⅱ was tagged by red fluorescent and then the stained cells were visualized under a Zeiss LSM710 confocal microscope.Furthermore,the numbers of autophagosomes in cells were visualized by transmission electron microscopy.Results The expression of p62,Beclin-land LC3 were significantly increased in METH group when compared with control group (P＜0.05).The level of LC3 was significantly increased in METH treated group compared with control group visualized under a Zeiss LSM710 confocal microscope.The numbers of autophagosomes in METH group are more than control group visualized by transmission electron microscopy.Conclusions Autophagy can be induced by METH in myocardial cells.

Preparation of Tilianin-loaded Nano-micelles and Evaluation of Prevention of Apoptosis in H9c2 Cells / 中国药学杂志

OBJECTIVE: To prepare nano-micelles with amphiphilic self-assembly poly (ethylene glycol)-co-poly (propylene sulfide) (PEG-PPS) copolymer as carrier to study the release characteristics of tilianin and investigate its activity to against H9c2 cell apoptosis in vitro. METHODS: An amphiphilic diblock PEG-PPS polymer was used as a carrier material to prepare the tilianin-containing nano-micelles by solvent evaporation. The morphology, particle size and distribution, drug loading and encapsulation rate and in vitro drug release behavior were characterized, H9c2 rat myocardial cell injury model was established by hypoxia/reoxygenation process. Using propranolol (Pro) as a positive control, the morphology of injured cardiomyocytes was observed by microscope. Cell proliferation and cell apoptosis was detected to evaluate the protective effect of blank micelles, tilianin and tilianin loaded nano-micelles on H9c2 cells induced by hypoxia/reoxygenation. RESULTS: Tilianin-loaded nano-micelles was spherical with uniform particle size distribution. The drug loading was 3.82%. The average particle diameter of tilianin-loaded nano-micelles was 137 nm, polydispersity coefficient was 0.162 and the encapsulation efficiency was 91.45%. In vitro drug release studies showed that there was no drug-induced burst release of tilianin-containing nano-micelles and sustained release characteristics, and the presence of hydrogen peroxide significantly promoted the release of tilianin from the nano-micelles. In vitro cytotoxicity experiments showed that when the concentration of tilianin 5 μg•mL-1, the cell viability of tilianin-loaded nano-micelles was significantly higher than the corresponding concentration of tilianin and PEG-PPS polymer nano-micelles. In vitro anti-apoptotic activity experiments show that tilianin-loaded nano-micelles on H9c2 cell apoptosis induced by hypoxia-reoxygenation have a significant inhibitory effect and was provided inhibition of apoptosis with propranolol. CONCLUSION: Tilianin-loaded nano-micelles have uniform particle size and distribution, sustained release and oxidation characteristics, has a significant protective and apoptosis-inhibiting effect on H9c2 cell injury induced by hypoxia-reoxygenation, which can be used as a promising drug delivery system for the treatment of myocardial ischemia-reperfusion injury.

Protective effect of ginsenoside Rb₁ on doxorubicin-induced myocardial autophagy / 中国中药杂志

Ginsenoside Rb₁ (Rb₁), which is one of the main ingredients derived from Panax ginseng, has been found to have extensive pharmacological activities including antioxidant, anti-inflammatory, anticancer properties. In this study, the effect of Rb₁ on doxorubicin-induced myocardial autophagy was studied with H9c2 as the study object. CCK-8 method, transmission electron microscope observation, fluorescence staining observation and Western blot were used to detect changes in H9c2 cell proliferation and autophagy after treatment. According to the results, doxorubicin could cause cell viability decrease, significant increase in the LC3-Ⅱ/LC3-I ratio and down-regulation of the expression of p62. Pretreatment with ginsenoside Rb₁ inhibited cell viability decrease and increase in doxorubicin-induced autophagic structure and LC3-Ⅱ/LC3-I ratio, and down-regulation of the expression of p62. In conclusion, doxorubicin could induce H9c2 cell death and induce autophagy, and ginsenoside Rb₁ showed a protective effect on DOX-induced cardiotoxicity, which may be correlated with suppression of DOX-induced autophagy.

Quantitative cardiotoxicity assessment of gambogic acid using multiple cellular phenotype analysis / 中国药理学与毒理学杂志

OBJECTIVE To evaluate the cardiotoxicity of a widen-spectrum antineoplastic drug, gambogic acid, through quantitative multiple cellular phenotypic characterization. METHODS H9c2 cell line was used as a model with doxorubicin (Dox) and amiodarone (Ami) as positive controls, hypaconi?tine as negative control and 0.1% DMSO as normal control. An optimized protocol was established to identify the morphology and function of cell nuclei. The effect of drugs on cell viability, nuclear area (Hoechst33342), mitochondria mass (MitoTracker Deep Red) and cytoplasmic calcium ion mobilization (Rhod2 AM)was studied. EC50 and Z′values were calculated to evaluate the degree of toxicology and to estimate the precision and false-positive rate, respectively. RESULTS Dose-response analysis indicated that EC50 of Dox on cell viability, nuclear area, mitochondrial mass was 0.72, 0.014 and 1.21μmol · L-1, respectively. On the other hand, EC50 of Ami on the parameters of cell viability, nuclear area and mitochon?drial mass was 14.83, 6.72 and 4.54μmol·L-1, respectively with Z′value above 0.5. Hypaconitine decreased the SER ridge of mitochondria. Gambogic acid caused significant mortality of H9c2 cells and induced nuclear shrinkage as Ami did. The EC50 values of cell viability and nuclear area were 0.24 and 1.16 μmol · L- 1. Meanwhile,gambogic acid disturbed the mitochondrial function as indicated by the increased mitochondrial area (EC50=0.44 μmol · L-1), abnormal SER Ridge(EC50=0.99 μmol · L-1) and decreased mitochondrial mass(EC50=1.21 μmol · L- 1). Cellular calcium mobilization was lower than normal (EC50=0.41 μmol · L-1). CONCLUSION The EC50 values of positive controls calculated from our assessment are similar those reported in literature. A multi-parameter and simultaneous evaluation enables a comprehensive analysis of the morphology of nuclei and mitochondria of cardiomyocytes and a preliminary assessment of the mechanisms of toxicity.

Protective effects and mechanism of extract from Cajanus cajan leaves against H2O2-induced oxidative injury on H9c2 cardiomyoblasts / 中草药

Objective: To investigate the protective effects and mechanism of the extract from Cajanus cajan leaves (ECCL) against H2O2-induced oxidative injury in H9c2 cardiomyoblasts. Methods: A model of H2O2-induced injury in H9c2 cardiomyoblasts was established. Cell viability was determined colorimetrically by MTT assay. The supernates and cells were collected, respectively, after the different treatments for measuring the LDH, MDA, and SOD levels with the corresponding detection kit according to the manufacturer's instructions. Western blotting was performed to exam the expression of p-Akt and p-eNOS in H9c2 cells respectively. Results: Compared with H2O2 group, the cell viability was increased significantly in ECCL + H2O2 groups (P < 0.01). The activity of LDH in the culture medium was decreased significantly (P < 0.05). The content of MDA in the culture medium was decreased significantly (P < 0.05). The activity of SOD was increased significantly (P < 0.01). Treated with ECCL, the expressions of p-Akt and p-eNOS in H9c2 cells injured from H2O2 were increased significantly (P < 0.01), When LY294002 (inhibitor of PI3K) was added, the effects of ECCL were cancelled. Conclusion: ECCL protects H9c2 cells against H2O2-induced oxidative injury partly through PI3K signaling pathway.

Protective effect of insulin on lipopolysaccharide - induced impairments of H9c2 cells and corresponding mec-hanism / 中华实用儿科临床杂志

Objective To research the protective effect of insulin(IN)on lipopolysaccharide(LPS)- induced impairments of rat cardiomyocytes H9c2,and the role of uncoupling protein 2(UCP2)in this process. Methods Using randomized controlled grouping,after cultured for 24 h,H9c2 cells were randomly divided into 5 groups as follows:con-trol group,LPS stimulation group(LPS group),LPS + 70 IU/ L IN group(IN 70 IU/ L group),LPS + 350 IU/ L IN group(IN 350 IU/ L group),and LPS + 700 IU/ L IN group(IN 700 IU/ L group). H9c2 cells in IN group were treated with 70 IU/ L,350 IU/ L or 700 IU/ L IN 15 min before LPS stimulation,and H9c2 cells in control group were treated with an equal volume of saline. After that,cells in group LPS and IN were treated with LPS for 24 h. Lactate dehydro-genase(LDH)in the culture was determined with LDH detecting assay kit. The activity of reactive oxygen species (ROS)and superoxide dismutase(SOD),and content of malonaldehyde(MDA)were determined by colorimetric detec-tion. Cell viability was evaluated by cell count kit - 8. The expressions of UCP2 in transcription and translation levels were detected through transcription polymerase chain reaction and Western blot respectively. Results The levels of LDH,MDA,and intracellular ROS in LPS group significantly increased compared with control group[LDH:(829. 3 ± 75. 3)U/ L vs(223. 5 ± 23. 6)U/ L,MDA:(60. 90 ± 5. 73)nmol/ mgprot vs(19. 70 ± 1. 99)nmol/ mgprot,ROS:(410. 2 ± 81. 6)U/ well vs(94. 3 ± 18. 5)U/ well,all P ﹤ 0. 05)],while the cell viability and SOD activity significantly decreased[cell viability:0. 822 ± 0. 058 vs 1. 012 ± 0. 023,SOD:(49. 20 ± 5. 81)U/ mgprot vs(89. 80 ± 2. 57)U/ mg-prot,all P ﹤ 0. 05]. And the mRNA and protein expressions of UCP2 in LPS stimulation group were up - regulated (1. 867 ± 0. 130 vs 1. 028 ± 0. 097,0. 288 ± 0. 018 vs 0. 180 ± 0. 008,all P ﹤ 0. 05). 350 IU/ L and 700 IU/ L IN inter-vention significantly decreased the levels of LDH,MDA and intracellular ROS[LDH:(568. 2 ± 35. 7)U/ L,(622. 8 ± 27. 6)U/ L vs(829. 3 ± 75. 3)U/ L,MDA:(29. 20 ± 4. 20)nmol/ mgprot,(42. 10 ± 2. 32)nmol/ mgprot vs(60. 90 ± 5. 73)nmol/ mgprot,ROS:(270. 3 ± 46. 8)U/ well,(301. 5 ± 16. 9)U/ well vs(410. 2 ± 81. 6)U/ well,all P ﹤ 0. 05], increased the cell survival and the levels of SOD activity[cell viability:0. 960 ± 0. 029,0. 906 ± 0. 039 vs 0. 822 ± 0. 058,SOD:(75. 20 ± 2. 21)U/ mgprot,(61. 20 ± 3. 38)U/ mgprot vs(49. 20 ± 5. 81)U/ mgprot,all P ﹤ 0. 05]. And IN with 350 IU/ L and 700 IU/ L increased the mRNA and protein expression of UCP2(3. 830 ± 0. 265,2. 855 ± 0. 215 vs 1. 867 ± 0. 130,0. 464 ± 0. 215,0. 355 ± 0. 006 vs 0. 288 ± 0. 018,all P ﹤ 0. 05). Compared with 70 IU/ L and 700 IU/ L IN group,350 IU/ L IN group had better results. Conclusions IN attenuates LPS - induced oxidative injury in H9c2 cells,which is probably mediated through up - regulating the expression of UCP2.

Effect of genipin on hypoxia/reoxygenation induced oxidative stress injury in H9c2 cell line / 中国药学杂志

OBJECTIVE: To investigate the effect of genipin on hypoxia/reoxygenation induced oxidative stress injury in H9c2 cell line. METHODS: For mimicking myocardial ischemia/reperfusion (I/R) injury, H9c2 cells were cultured in vitro and established hypoxia/reoxygenation induced oxidative stress injury model. H9c2 cells were divided into six groups: control group, H/R group, H/R+0.5 μmol·L-1 genipin group, H/R+1.25 μmol·L-1genipin group, H/R+2.5 μmol·L-1 genipin group and H/R+10 μmol·L-1 genipin group. Cell viability was detected by cell counting kit-8 assay (CCK-8). The levels of lactate dehydrogenase (LDH), intracellular total superoxide dismutase (T-SOD) and malondialdehyde (MDA) were assessed using microplate reader. Confocal laser scanning microscope was performed to examine the production of reactive oxygen species (ROS) and the level of mitochondrial calcium (m) as well as the depolarization ratio of mitochondrial membranes potential(ΔΨm). The protein expression of cytochrome-C was detected by Western-blot. RESULTS: Comparing to control group, the cell viability of H/R group was significantly decreased in a time-dependent manner(r=-0.82,P<0.01). Low concentration(1.25-40 μmol·L-1) of genipin could improve cell viability exposed to H/R treatment (P<0.05), on the contrary, high concentration(80-320 μmol·L-1) of genipin remarkably reduced the cell viability (P<0.05). In compared with H/R group, the levels of LDH release, MDA production and ROS production, the level of m, depolarization ratio of ΔΨm and the protein expression of cytochrome-c in H/R+(1.25-10 μmol·L-1) genipin groups were notably lessened, while the level of T-SOD was increased(P<0.01 or P<0.05). CONCLUSION: Genipin could reduce H/R-induced oxidative stress injury, the mechanism might be connected with balancing the oxidative stress products and anti-oxidation enzyme system as well as improving mitochondrial dysfunction.

Establishment of a hypoxia/reoxygenation model of H9 c2 cell using hypoxia/anoxic workstation / 中国生化药物杂志

Objective To investigate optimal method of establishing hypoxia/reoxygenation(H/R) model of H9c2 cell by using hypoxia/anoxic workstation under different conditions in hypoxia.Methods H9c2 cell was placed into hypoxia/anoxic workstation and simultaneously cultured with complete medium, glucose-free DMEM and acidic hypoxic solution for 1,2,4,6 and 8 h respectively, and then reoxygenated with complete medium for 1 h in normoxic incubator.The level of ROS was measured by flow cytometry.The cell viability was detected by MTT assay.The cellular morphology was observed by inverted microscope.Results With the extension of cell hypoxia time, there were no significant differences in the ROS level and cell viability in complete medium-and glucose-free DMEM-treated H/R groups compared with control group(P<0.05).There was no obvious morphologic change observed with inverted microscope, either.Nevertheless, when H9c2 cells were treated with acidic hypoxic solution in hypoxia, the ROS level continuously increased and the cell viability decreased with the extension of cell hypoxia time ( P<0.01 ).Since H:1 h/R:1 h, some of the cells shrunk and a few necrotic cells floated in the media under the inverted microscope , and the damage was aggravated with the extension of hypoxia time.After the cells were exposed in hypoxia for 8 h, they wrinkled to be round and a large number of floating necrotic cells were observed.When the cells were reoxygenated for 1 h, the cytomembrane was not smooth and there were still a few necrotic cells floating in culture dish .Conclusion The H9c2 cell H/R model with good repeatability can be established successfully by using hypoxia/anoxic workstation combining with acidic hypoxic solution.

The Effects of Nonylphenol on Calcium Signaling and Cell Proliferation in H9c2 Cell and Its Mechanism / 中国医科大学学报

Objective To observe the effects of nonylphenol(NP)on the intracellular calcium concentration changes and cell proliferation,and the involvement of GPR30 receptor in H9c2 cell. Methods The intracellular calcium concentration changes were recorded by using intracellular calcium determination method and cell proliferation was observed by MTT method in H9c2 cell. Results NP(1×10-10 mol/L)increased the intra?cellular calcium concentration changing amplitude and promoted the proliferation of H9c2 cells,while NP(1×10-6 mol/L)decreased intracellular calcium concentration changing amplitude and suppressed cell proliferation. G15 could block the promoting effect of 1×10-10 mol/L NP on the intracel?lular calcium concentration and cell proliferation,but could not block the inhibition of 1×10-6 mol/L NP on the intracellular calcium increase and cell proliferation. Conclusion The results indicate that NP affect rapid calcium signal changes and cell proliferation in non?monotonic dose dependent manner,and its mechanism may be due to the different involvement of GPR30 receptor in different concentrations.

Effects of pH, Buffer System and Lactate on the Simulated Ischemia-reperfusion Injury of H9c2 Cardiac Myocytes

We elucidated the effects of various components of ischemic medium on the outcome of simulated ischemia-reperfusion injury. Hypoxia for up to 12 hours induced neither apoptotic bodies nor LDH release. However, reoxygenation after 6 or 12 hours of hypoxia resulted in a marked LDH release along with morphological changes compatible with oncotic cell death. H9c2 cells were then subjected to 6 hours of simulated ischemia by exposing them to modified hypoxic glucose-free Krebs-Henseleit buffer. Lowered pH (pH 6.4) of simulated-ischemic buffer resulted in the generation of apoptotic bodies during ischemia, with no concomitant LDH release. The degree of reperfusion-induced LDH release was not affected by the pH of ischemic buffer. Removal of sodium bicarbonate from the simulated ischemic buffer markedly increased cellular damages during both the simulated ischemia and reperfusion. Addition of lactate to the simulated ischemic buffer increased apoptotic cell death during the simulated ischemia. Most importantly, concomitant acidosis and high lactate concentration in ischemic buffer augmented the reperfusion-induced oncotic cell death. These results confirmed the influences of acidosis, bicarbonate deprivation and lactate on the progression and outcome of the simulated ischemia-reperfusion, and also demonstrated that concomitant acidosis and high lactate concentration in simulated ischemic buffer contribute to the development of reperfusion injury.

Inhibition of Sarcoplasmic Reticulum Ca2+ Uptake by Pyruvate and Fatty Acid in H9c2 Cardiomyocytes: Implications for Diabetic Cardiomyopathy

High extracellular glucose concentration was reported to suppress intracellular Ca2+ clearing through altered sarcoplasmic reticulum (SR) function. In the present study, we attempted to elucidate the effects of pyruvate and fatty acid on SR function and reveal the mechanistic link with glucose-induced SR dysfunction. For this purpose, SR Ca2+-uptake rate was measured in digitonin-permeabilized H9c2 cardiomyocytes cultured in various conditions. Exposure of these cells to 5 mM pyruvate for 2 days induced a significant suppression of SR Ca2+-uptake, which was comparable to the effects of high glucose. These effects were accompanied with decreased glucose utilization. However, pyruvate could not further suppress SR Ca2+-uptake in cells cultured in high glucose condition. Enhanced entry of pyruvate into mitochondria by dichloroacetate, an activator of pyruvate dehydrogenase complex, also induced suppression of SR Ca2+-uptake, indicating that mitochondrial uptake of pyruvate is required in the SR dysfunction induced by pyruvate or glucose. On the other hand, augmentation of fatty acid supply by adding 0.2 to 0.8 mM oleic acid resulted in a dose-dependent suppression of SR Ca2+-uptake. However, these effects were attenuated in high glucose-cultured cells, with no significant changes by oleic acid concentrations lower than 0.4 mM. These results demonstrate that (1) increased pyruvate oxidation is the key mechanism in the SR dysfunction observed in high glucose-cultured cardiomyocytes; (2) exogenous fatty acid also suppresses SR Ca2+-uptake, presumably through a mechanism shared by glucose.

Formation of Intercellular Junction between Cardiomyocyte and H9c2 Cell Line in Co-Culture / 체질인류학회지

Recently, new treatments for human heart disease such as ischemia, infarction, cardiomyopathy, coronary heart disease have been developed. transplantation various kinds of cells from skeletal muscle, endothelium, mesenchyme, hemopoietic tissue to injured area after infarction were challenged. It's so called 'Cell Transplantation'. This therapeutic strategy already adopted and got a good result in clinical trial. But several limitations are still remained, including ethics, donor cell numbers, side effects, therapeutic efficiency. In this research, we investigated the formation of intercellular junction and synchronous contraction between cardiomyocyte and H9c2 cell line in co-culture to establish experimental model in vitro for cell transplantation. For this purpose, two kinds of cells, primary cultured cardiomyocyte and H9c2 (cardiomyoblast cell line) were used. Cultured cardiomyocytes had repetitive contraction-relaxation pattern along longitudinal axis both in single and coculture. But their contractions were slower, less regular, less strong in co-culture than in cardiomyocyte culture only. H9c2 cells did not contracted actively themselves, but moved toward cardiomyocyte passively coincided with contraction. In contact region between two kinds of cells, there was no signal after immunocytochemical staining labeled with connexin43 (gap junction), desmoplakin (desmosome), N-cadherin (adherent junction) even though they had membrane contact. Moreover, F-actin and striation were less developed. These results suggested that co-culture system interfere with remodelling of contractile apparatus, intercellular junction formation as well as contraction-relaxation. Furthermore cardiomyocyte could not induce H9c2 cells differentiation into cardiomyocyte. Therefore, much more research would be essential for clinical application of cell transplantation and this study would be the basic source for further study of new therapy of myocardial disease and building up in vitro model.