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1.
AIM: To observe the influence of glycine on intracellular free calcium, the concentration of tumor necrosis factor-α and the survival rate of myocardial cells during hypoxia/reoxygenation (H/R). METHODS: The simulated model of myocardial ischemia-reperfusion with the primary cultured cardiomyocytes of neonatal rats was established, and the cultured cardiomyocytes were divided into seven groups, control group, hypoxia/reoxygenation group, glycine (0.5 mmol/L) plus hypoxia/reoxygenation group, glycine (1.0 mmol/L) plus hypoxia/reoxygenation group, glycine (2.0 mmol/L) plus hypoxia/reoxygenation group, glycine (4.0 mmol/L) plus hypoxia/reoxygenation group, 4.0 mmol/L glycine group. RESULTS: Within certain concentration (0.5-2.0 mmol/L), the glycine could inhibit the calcium overload resulting from hypoxia/reoxygenation injury in cells in a dose-dependent manner with the optimal inhibitory effect at 2.0 mmol/L. Glycine inhibited the secretion of tumor necrosis factor-α from myocardial cells and increased the survival rate of myocardial cells. CONCLUSION: Glycine has a protective effect on hypoxia/reoxygenation myocardial cells, which may be related to inhibiting calcium overload and decreasing the production of tumor necrosis factor-α.  相似文献   

2.
AIM: To observe the role of cyclooxygenase-2 (COX-2) in injury induced by hypoxia and reoxygenation in cultured rat cortical neurons and protective effects of COX-2 specific inhibitor NS398.METHODS: Primary rat cortical neuronal cells were cultured. Experiments were divided into control group, hypoxia/reoxygenation group and hypoxia/reoxygenation with COX-2 inhibitor group. Cell viability was measured by MTT assay. COX-2 protein expression was examined by Western blotting. Apoptosis was measured by DNA agarose electrophoresis.RESULTS: The expression levels of COX-2 increased significantly after neurons were treated with hypoxia and reoxygenation, compared with control group and hypoxia/reoxygenation with COX-2 inhibitor group (P<0.05). COX-2 specific inhibitor NS398 protected neurons from death (P<0.05 and P<0.01), DNA fragmentation analysis showed DNA fragmentation was inhibited significantly by NS398.CONCLUSION: COX-2 is involved in the pathogenesis of neuron apoptosis induced by hypoxia/reoxygenation. COX-2 specific inhibitor significantly protects cortical neurons against hypoxia/reoxygenation injury and inhibits apoptosis induced by hypoxia.  相似文献   

3.
AIM: To investigate the effect of interleukin-2(IL-2) on the intracellular calcium in electrically stimulated adult rat ventricular myocytes during anoxia and reoxygenation. METHODS: The isolated cardiac ventricular myocytes were exposed to 5 min anoxia followed by 10 min reoxygenation. Chemical anoxia was introduced by Krebs-Henseleit(K-H) solution containing 10-3 mol/L sodium dithionite. The spectrofluorometric method was used to verify intracellular calcium transient with fura-2/AM as calcium fluorescence probe. RESULTS: It was shown that during anoxia, the amplitude of Ca2+ transient was decreased, diastolic [Ca2+]i, time to peak and time to relaxation of Ca2+ transient were increased. All the parameters were got back but did not returned to the pre-anoxia level during reoxygenation. IL-2 at 2×105 U/L administrated during anoxia aggravated the effect of rexoxygenation on [Ca2+]i transient. Pretreatment with a specific κ opioid antagonist, nor-BNI(10-8 mol/L), abolished the effect induced by IL-2 during anoxia on the [Ca2+]i transients, whereas specific δ opioid antagonist, naltrindole(10-6 mol/L), did not cancel the effect. CONCLUSION: It is concluded that administration of IL-2 during anoxia aggravated the effect of reoxygenation on the [Ca2+]i transients of isolated ventricular myocytes, which was mediated by cardiac κ opioid receptor pathway.  相似文献   

4.
AIM: To investigate the role of nitric oxide synthase (NOS), soluble guanylyl cyclase (sGC) and protein kinase C (PKC) signaling in tumor necrosis factor-α (TNF-α)-induced cardioprotection against hypoxia/reoxygenation (H/R) injury. METHODS: Neonatal rat ventricular myocytes were pretreated with TNF-α or sodium nitroprusside (SNP) or L-arginine (L-Arg), respectively, for 12 h and then subjected to continuous hypoxia for 12 h, followed by reoxygenation for 6 h. The manganese superoxide dismutase (Mn-SOD) activity of the cells was measured after H/R. Myocyte injury was determined by the release of lactic dehydrogenase (LDH). RESULTS: TNF-α (105 U/L) significantly increased the Mn-SOD activity and decreased release of LDH from ventricular myocytes. The cardioprotection against H/R injury was induced by the pretreatment with SNP (5 μmol/L) or L-Arg (5 mmol/L), which was blocked by ODQ (10 μmol/L), the specific sGC inhibitor, and Chel (5 μmol/L), the specific PKC inhibitor. Pretreatment with L-NAME (100 μmol/L), ODQ, Chel, antoxidant 2-MPG (400 μmol/L) or tyrosine kinase inhibitor genistein (50 μmol/L) attenuated the increased Mn-SOD activity and reduced LDH level induced by TNF-α. CONCLUSION: The results suggest that NO may play a role in TNF-α-induced cardioprotection, which is mediated by sGC and PKC.  相似文献   

5.
AIM:To investigate different intracellular concentration of Ca2+ in uterine myometrial cells at term and non-term.METHODS:The living cells suspensions were made to measure intracellular Ca2+ concentrations after stainned by calcium fluorescent indicator Fluo-3 AM, then examined by laser scanning confocal microscope (LSCM).RESULTS:Intracelluar Ca2+ showed very stronger red positive signal in myometrial cells at term than that in non-term cells. [Ca2+]i were (35±8.1) nmol/L at non term and (75±7.3) nmol/L at term, which had significant difference compared with each other (P<0.05).CONCLUSION:Increase in [Ca2+]i in myometrial cells might play a very important role labor.  相似文献   

6.
AIM: To investigate the protective effect of calcium antagonists on anoxia/reoxygenation (A/R) injury of cardiomyocytes. METHODS: Primary-cultured cardiomyocytes were divided into four groups, namely A/R, A/R+nifedipine (Nif), A/R+ruthenium red (Ru)+heparin (Hep) and control groups. The following parameters were measured in all groups: intracellular calcium concentration (i), cardiac cell viability, ATP content, lactate dehydrogenase (LDH) activity in the medium, PKC and MAPK activity and 3[H]-Leucine (3[H]-Leu) incorporation. RESULTS: In comparison with A/R group,A/R+nifedipine (Nif) and A/R+ruthenium red (Ru)+heparin (Hep) groups showed a marked decrease in[Ca2+]i and LDH content,and a significant increase in cell viability, ATP content, activity of PKC and MAPK and [3H]-Leu incorporation (P<0.05 or P<0.01). CONCLUSION: A/R mediated Ca2+ overload resulted in cardiomyocyte injury, which could be attenuated by blocking Ca2+ entry and release.  相似文献   

7.
AIM:To study the protective effect of cardiomyopeptidin (CMP) attributed to polypeptide on cultured myocardial cells injured by anoxia-reoxygenation.METHODS:The anoxia-reoxygenation injury model were developed, anoxia for 60 min and reoxygenation for 30 min. The effect of CMP on myocardial ultrastructure was observed. [Ca2+]i was estimated with adherent cell analysis and sorting 570(ACAS 570) laser cytometer and measured with fluorescent dye Fura-2-AM, the lipid fluidity of cellular membrane was determined by fluorescence polarization technique. RESULTS:CMP could obviously improve the ultrastructure of myocardial cells and dose-dependently decrease[Ca2+] i and increase the lipid fluidity of cellular membrane, CMP also could markedly reduce the chromaticity value of pseudo-colour graphic model of Ca2+. CONCLUSION:Cardiomyopeptidin has an obvious protective effect on cultured myocardial cells injured by anoxia-reoxygenation, this may be related to its effect of decreasing [Ca2+]i and increasing lipid fluidity of cellular membrane.  相似文献   

8.
AIM:To study the effect of salvia miltiorrhiza (SM) on cell contraction and intracellular calcium of enzymatically isolated rat ventricular myocytes during normoxia and anoxia/reoxygenation.METHODS:Contraction and intracel ular calcium were determined with video tracking system and spectrofluorometric method,and the chemical anoxic method was employed. RESULTS:The ±dL/dtmax, dL of cell contraction and the amplitude of [Ca2+]i in the cardiomyocytes following SM treatment were decreased in a dose-dependent manner. During anoxia, the ±dL/dtmax, dL and amplitude of [Ca2+]i were decreased, while the diastolic Ca2+ level was elevated compared with control group. All the contractile parameters and the diastolic Ca2+ level were back toward pretreatment values during reoxygenation, but could not return to control level. After the treatment with SM (3 g/L), ±dL/dtmax and dL of cell contraction and the amplitude of [Ca2+]i were higher and the diastolic Ca2+ level was lower than those in anoxia/reoxygenation group. CONCLUSION:SM antagonized effects of anoxia and reoxygenation on cell contraction and intracellular calcium in isolated ventricular myocytes.  相似文献   

9.
AIM:To study the effect of ligustrazine on pulmonary hypertensive rats induced by hypoxic hypercapnia. METHODS:Thirty rats were randomly divided into three groups:control group(A),hypoxic hypercapnic group(B), hypoxic hypercapnia+ligustrazine(lig.) group(C). RESULTS: (1) Mean pulmonary arterial pressure(mPAP)of group B was significantly higher than that of group A and mPAP of group C was significantly lower than that of group B(P<0.01),differences of mean carotid pressure(mCAP) were not significant among three groups (P>0.05); (2)Electron microscopy and immunohistochemistry showed ligustrazine could inhibit the diposition of collagenous fiber(collagen typeⅠ)in pulmonary arterioles induced by hypoxic hypercapnia; (3) Plasma endothelin level of group C was significantly lower than that of group B (P<0.01), serum (NO 2-/NO3-) of group C was significantly higher than that of group B (P<0.01). CONCLUSION:Ligustrazine can inhibit pulmonary hypertension and the diposition of collagen type Ⅰ in pulmonary arterial wall induced by hypoxic hypercapnia.  相似文献   

10.
AIM:To observe the influence of captopril on intracellular free calcium concentration ([Ca2+] i) and the involved ion channels mechanisms in cardiac myocytes of the neonatal rat undergone anoxia-reoxygenation injury.METHODS:The anoxia-reoxygenation model in cultured neonatal rat ventricular myocytes was established.Groups were divided into ① normal;② anoxia-reoxygenation;③anoxia-preconditioning (5 min anoxia+5 min reoxygenation);④ captopril preconditioning.Flou-3 /AM loading and flow cytometry technique were used to observe the [Ca2+]i,and whole-cell patch clamp technique was used to record the L-type calcium current and Na+/Ca2+ exchange current.RESULTS:① Compared to normal group,[Ca2+]i in anoxia -reoxygenation group was increased significantly (789.42±9.05 vs 414.08±37.40,P<0.01),L-type calcium current density was decreased (P<0.01),the current-voltage curve was moved up,the inactivation curve was moved left and Na+/Ca2+ exchange current was increased in anoxia-deoxygenating.② Compared to anoxia-reoxygenation group,anoxia and captopril preconditioning resulted in a significant decrease in [Ca2+]i (593.84±5.06,507.08±31.89 vs 789.42±9.05,P<0.01),and a significant increase in L-type calcium current density (P<0.01),the current-voltage curve was moved down,the inactivation curve was moved right and Na+/Ca2+ exchange current was decreased ③ Compared to normal oxygen condition,the anoxia and captopril precondition resulted in a lightly increase in [Ca2+]i (507.08±31.89 vs 414.08±37.40,P<0.05) and Na+/Ca2+ exchange current.④ Compared to anoxia-preconditioning group,captopril-preconditioning resulted in no significant difference in all the markers mentioned above.CONCLUSIONS:The anoxia-reoxygenation injury in cardiac myocytes results in [Ca2+]i abnormal increase and calcium overload by increasing Na+/Ca2+ exchange current.Late preconditioning in cardiac myocytes is triggered by transient and repeated anoxia and captopril,which slightly increases Na+/Ca2+ exchange current and [Ca2+]i and restraines the abnormal increasing of Na+/Ca2+ exchange current and calcium overload induced by subsequenced anoxia-reoxygenation injury,so it plays an delayed protective role in cardiac myocytes.L-typed calcium passage is not involved in calcium overloaded and late preconditioning of calcium in myocytes during reperfusion.  相似文献   

11.
AIM: The experiment was designed to study the effect of compound Danshen dripping pills (DSDP) on myocardium with anoxin/reoxygenation. METHODS: The myocardial anoxin/reoxygenation model was made in perfused isolated rat heart. DSDP and isosorbide dinitrate (ID) were given at the time of pre-perfusion and reperfusion, then HPLC and H-600 electron microscope were used to detect the change of high energy phosphate and the ultrastructure of myocardial cell. RESULTS: ① The contents of AMP, ADP, ATP and AN in myocardium in only anoxin/reoxygenation group were obviously lower than those in the control group (P<0.01).② The contents of AMP, ADP, ATP and AN in myocardium in the groups with DSDP were higher than those in only anoxin/reoxygenation group (P<0.01), also higher than those in the groups with ID (P<0.01). In the two groups with DSDP, the contents of ATP and AN were close to normal (P>0.05). ③ In the groups with ID, the contents of AMP, ADP, ATP and AN were distinctively lower than those in the control group (P<0.01). CONCLUSION: These results indicated that DSDP administration could significantly increase the content of high energy phosphate in myocardium with anoxin/reoxygenation and decrease the ultrastructure injury of myocardial cells, and its protective effect was better than ID.  相似文献   

12.
AIM:To investigate the protective effect of cardiomyopeptidin on cultured myocardial cells damaged by adriamycin in neonatal rats.METHODS:The activities of CPK, LDH and the dehydrogenase of mitochondria in the cells damaged by adriamycin were observed in the presence or absence of cardiomyopeptidin, i was measured with fluorescent dye Fura-2-AM.RESULTS:Cardiomyopeptidin reduced the activities of CPK and LDH and increased the activities of dehydrogenase of mitochondria in a dose-dependent manner; CMP also dose-dependently decreased i.CONCLUSION:Cardiomyopeptidin has a protective effect on cultured rat neonatal myocardial cells damaged by adriamycin.  相似文献   

13.
AIM: To study the effect of experimental acute necrotizing pancreatitis (ANP) on sodium and L-type calcium current in rat cardiomyocytes. METHODS: INa and ICa-L were recorded using whole cell patch-clamp techniques from left ventricular myocytes in ANP model established by retrograde injection of 3.5% sodium taurocholate 2.5 mL/kg into pancreatic duct. RESULTS: Peak INa current density (at -30 mV) was significantly reduced in ANP [(12.45±2.26)pA/pF,n=16] compared with sham [(25.32±3.31)pA/pF,n=14], P<0.01; ICa-L current density (at +10 mV) was also significantly reduced in ANP [(3.63±0.65)pA/pF,n=16] compared with sham [(5.46±1.03)pA/pF,n=12], P<0.05. CONCLUSIONS: There were changes in both INa and ICa-L in cardiomyocytes of ANP. These changes may underlie the altered excitability and abnormally short transmembrane action potentials and repolarization of cardiomyocytes, thus contributing to arrhymias in ANP.  相似文献   

14.
AIM: To study effect of endogenous carbon monoxide on intracellular calcium concentration and explore the mechanism in brain protection of endogenous CO in focal cerebral ischemia in rats. METHODS: SD rats were divided into three groups randomly, which including hemin, ZnPP group and saline group as control. Respectively saline, hemin, ZnPP were injected intra-peritoneally twelve hours before middle cerebral artery was occluded. Twenty four hours after MCAO model was set up, the concentration of carbon monoxide in blood and intracellular calcium in neural cells was examined. RESULTS: Contrast to saline group, the concentration of CO in blood rose up while intracellular calcium in occluded side decreased in hemin group; the concentration of CO in blood went down while intracellular calcium in occluded side rose up in ZnPP group, there was significant difference among them (P<0.05). Hemin and ZnPP had no effect on intracellular calcium in non-occluded sides (P>0.05). CONCLUSIONS: It may be one of mechanisms on brain protection in ischemic cerebral tissue that carbon monoxide affected intracellular calcium concentration of neural cells by regulating Ca2+-K+ channel on cell membrane as a messenger gaseous molecular and neurotransmitter.  相似文献   

15.
AIM: To observe the effects of harvested wound exudate on intracellular free Ca2+ in epidermal stem cells (ESCs) in vitro, and to investigate the relationship between mitogen-activated protein kinases (MAPKs) signal pathways and Ca2+ mobilization in this condition.METHODS: Wound exudate was harvested from the 80 full-thickness wounds produced on both sides of the back in 40 adult Wistar rats. ESCs were isolated, purified from neonatal Wistar rats by referring to the formerly records and binding our ideas. When the cultured cells showed up clone growing, they were divided into five groups as follows: group A: control group (no-treatment); group B: only treatment with wound exudate; group C: treatment with wound exudate and PD98059; group D: treatment with wound exudate and SB203580; group E: treatment with wound exudate, PD 98059 and SB203580. Then, the cells were incubated with fluorescence Ca2+ dye fluo-3/AM at 37 ℃ for 30 min, and measured by using laser scanning confocal microscope.RESULTS: The results showed that the fluorescent intensity of group B was higher than that in group A. A phenomenon of calcium oscillation was found in group C and group D. Furthermore, a rapid decrease of fluorescent intensity was observed in the cells that were preincubated with PD98059 and SB203580 at the same time. CONCLUSION: Based on above results, we propose that wound exudate can directly induce an increase in intracellular free Ca2+concentrations of ESCs. MAPKs signaling pathway has an important function of feedback regulation for free Ca2+ mobilization of ESCs in this condition, and also is capable of affecting the biological behaviour of epidermal stem cells.  相似文献   

16.
AIM: The aim of this work is to investigate the protective effects of Ginsenoside Rb1 (Rb1) on apoptosis induced by hypoxia/hypoglycemia and reoxygenation in cultured rat hippocampal neurons. METHODS: Apoptosis were measured by flow cytometry; Morphological changes and neuronal necrosis were examined under microscope; The leakage of lactic dehydrogenase (LDH) and the product of nitric oxide (NO) were measured. RESULTS: hypoxia/hypoglycemia cultures for 5 h and reoxygenation induced neuronal apoptosis and necrosis,and significantly increased the leakage of LDH and the product of NO. The effects were enhanced with the extending time of reoxygenation. Rb1 could significantly decrease the percentage of neuronal apoptosis and necrosis, and reduce the leakage of LDH and the product of NO. CONCLUSION: Rb1 had an effect of anti-neuronal apoptosis. This effect might be related to the inhibition of the activity of NO synthase and NO production.  相似文献   

17.
AIM:To study the effect of xin-tong capsule on nitric oxide production and cGMP content of ventricular myocardium in rats with experimental myocardial ischemia. METHODS:Rat model of acute myocardial ischemia induced by pituitrin was used in this study, and the lift of ST segment in ECG was used as the index of myocardial ischemia. The NO2-/NO3- and cGMP contents of ventricular myocardium in rats with myocardial ischemia were determined.RESULTS: NO2-/NO3- and cGMP contents in ventricular myocardium of myocardial ischemia were (486±59) nmol/g protein and (0.38±0.08) nmol/g protein, respectively, and markedly lower than those of control (P<0.01). After administration of Xin-Tong capsule, contents of NO2-/NO3- and cGMP in ventricular myocardium of rats with myocardial ischemia were obviously elevated . In comparison with control, ST segment of ECG in rats with myocardial ischemia was lifted, and the lift peak of ST segment occur in 45 min after myocardial ischemia (P<0.01). Pretreatment of Xin-Tong capsule can improve conditions of myocardial ischemia . CONCLUSION:Xin-Tong capsule can elevate the contents of nitric oxide and cGMP, and attenuate myocardial ischemia injury in rats.  相似文献   

18.
AIM: To investigate the effect of hypoxia on persistent sodium current (INap) in single ventricular myocyte isolated from acute myocardial infarction (AMI) heart of rats and to study the mechanisms of cardiac arrhythmias that occur after AMI. METHODS: AMI model was induced by ligating the left anterior descending coronary artery in rats. The whole-cell patch clamp technique was used to record the current in epicardial myocytes in infarcted region from rats at 3 week after AMI. RESULTS: In normoxic conditions, the current density of INap in cardiomyocytes of fake operation (FO) and AMI hearts was 0.144±0.022 pA/pF (n=9), 0.121±0.013 pA/pF (n=9,P<0.01), respectively, which was blocked by tetrodotoxin (TTX). The amplitude of INap was gradually increased with the prolongation of hypoxia time, but the increase in extent of INap in FO cells was significant bigger than that in AMI cells. The INap was blocked by 1 mmol/L glutathione. CONCLUSIONS: After AMI, the amplitude of INaP in infarcted and noninfarcted myocardium showed differences both in normoxic and hypoxic conditions, which increased dispersion of repolarization. This may be one of the reasons of reentrant ventricular arrhythmias that occur after AMI.  相似文献   

19.
AIM: To investigate the effects of salidroside on intracellular free calcium concentration [Ca2+]i, apoptosis, mitochondrial membrane potential (MMP) and activity during injury induced by hypoxia/hypoglycemia in cultured SH-SY5Y cells. METHODS: Mitochondrial activity was measured by methylthiazolyl tetrazolium test. MMP,[Ca2+]i and apoptosis were measured by flow cytometry. RESULTS: SH-SY5Y cells were cultured in a hypoxia/hypoglycemia condition for 2, 4, 6 and 12 h,[Ca2+]i and apoptosis rate significantly increased compared with control group (P<0.01). After hypoxia /hypoglycemia cultures, MMP and mitochondrial activity declined 29.17% (P<0.01) and 38.80% (P<0.01) at 2 h, 56.72% (P<0.01) and 63.58% (P<0.01) at 12 h, were lower than that in control group (P<0.01). Salidroside significantly decreased [Ca2+]i and apoptosis rate, and increased MMP and mitochondrial activity in hypoxia /hypoglycemia-treated SH-SY5Y cells. CONCLUSIONS: Salidroside might inhibit the decline in MMP and mitochondrial activity induced by hypoxia /hypoglycemia, and has an inhibitory effects on neuronal apoptosis. The mechanism might be related to inhibiting intracellular calcium overload.  相似文献   

20.
AIM: To observe the effects of some component of Chinese herbs for external use on proliferation of human umbilical vein endothelial cells (HUVEC) and investigate the mechanism of promoting tissue repair. METHODS: The method of MTT was used to examine the effects of Rg1, Rh1, perlolyrine, cinnamyl aldehyde, muscone, astragaluspolysaccharin (APS), velver antler polypeptide (VAP) and soluble extract of boswellia carterii birdw (BCB) on proliferation of HUVEC. RESULTS: APS did not promote proliferation of HUVEC at 9.75 mg/L-2.5 g/L; Rh1 promoted proliferation of HUVEC at 1.94 mg/L-0.5 g/L (P<0.05 or P<0.01), and Rg1 inhibited proliferation of HUVEC at 31 mg/L (P<0.05); VAP promoted proliferation of HUVEC at 1 mg/L-0.5 g/L with optimal dose of 10 mg/L (P<0.01), Cinnamyl aldehyde promoted proliferation of HUVEC at 2 g/L(P<0. 05); Muscone and soluble extract of BCB inhibited proliferation of HUVEC at 1 g/L, 0.5-2.5 kg/L(P<0. 01), respectively; Perlolyrine inhibited proliferation of HUVEC at 0.125 g/L-0.5 g/L(P<0. 01). CONCLUSION: The external herbs for supplementing Qi and warming Yang can promote HUVEC proliferation and improve angiogenesis during tissue repair. The external herbs for promoting blood circulation and accelerating capillary movement may have influence upon other stages of tissue repair.  相似文献   

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