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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.
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Objective To investigate whether ROS/JNK/Egr-1 signaling pathway was activated in cardiomyocytes after hypoxia/reoxygenation ( H/R).Methods H9c2 cardiomyocytes were grouped randomly as follows: control group, H/R group, control +the ROS donor xanthine oxidase /hypoxanthine (XO/HX) group, H/R +the ROS scavenger edaravones (EDA) group, H/R +the ROS scavenger N-acetyl-L-cysteine (NAC) group, H/R +JNK inhibitor SP60012 group.To establish H9c2 H/R models and the myocardial cells were treated with different concentrations of EDA (2 × 10 -6,2 ×10 -5,2 ×10 -4 M), NAC (5 ×10 -4,2 ×10 -3,8 ×10 -3 M), XO/HX (1mU/mL/1.2 ×10 -4 M , 3mU/mL/3.6 ×10 -4 M, 5mU/mL/6.0 × 10 -4 M) and SP600125 (2 ×10 -5 M).ROS level was measured by flow cytometry, and Egr-1, p-JNK and total JNK protein levels were detected by Western blot.ResuIts ROS levels and Egr-1 protein levels in H/R group were significantly higher than control group (P<0.05).The moderate and high concentrations EDA and NAC of ROS scavenger significantly decreased the high levels of ROS and Egr-1 protein ( P<0.05 ) , but there were no significant differences of low concentration.There was a significant positive correlation between ROS levels and Egr-1 protein (r=0.91,P<0.01).JNK activation levels in each concentrations of XO/HX were significantly higher than control group, and JNK activation increased with the increasing of XO/HX concentrations (P<0.05).JNK activation level in H/R group was higher than control group, after treated by EDA and NAC of ROS scavenger and JNK inhibitor, JNA activation reduced (P<0.05).Egr-1 protein levels in H/R group was higher than that in control group, and JNK inhibitor reduced the expression of Egr-1 protein induced by H/R.ConcIusion H/R activates ROS/Egr-1 signaling pathway in H9c2 cardiomyocytes, and JNK activation plays an important role in this pathway.
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AIM: To investigate the changes in nNOS and iNOS expression of hippocampal CA3 pyramidal neurons and NO - 2/NO - 3 level of hippocampal homogenate of rats induced by stress, and to explore the effect of phenytoin on them. METHODS: Rats were subjected to forced-swimming stress, phenytoin was administered(ip) at 30 min before stress. Using the immunohistochemistry and the computerized image technique, the expression levels of nNOS and iNOS of rat hippocampal CA3 pyramidal neurons were assayed quantitatively, and the NO - 2/NO - 3 level of hippocampal homogenate was also measured using nitric acid deoxidize enzyme method. RESULTS: The nNOS average grey degree of hippocampal CA3 pyramidal neurons was significantly lower in stress group (155 42?3 77)than that in control group(164 54?4 62)and in stress plus phenytoin group(164 27?2 55)( P
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AIM To study the effects of quateranary ammonium salt derivative (F 2) of haloperidol on ischemia and reperfusion injury in rat hearts. METHODS Ischemia and reperfusion injury in rat hearts was induced by occluding the left anterior descending coronary artery for 30 min and restoring blood reperfusion for 30 min. F 2 (1, 2, 4 mg?kg -1 , respectively) was intravenously injected before heart ischemia. Plasma creatine kinase (CK), creatine kinase isoenzyme MB(CK MB), lactate dehydrogenase(LDH),? Hydroxybutyrate dehydrogenase (HBDH), grutamic oxalacetic transaminase(GOT), superoxide dismutase (SOD) activity and malondiadehyde (MDA) contents were measured. The pathologic changes of ischemia and reperfusion myocardium were observed on the transmission electron microscopy. RESULTS F 2 reduced the release of CK,CK MB LDH,HBDH,GOT from I/R rat hearts, increased the activity of SOD and decreased the MDA contents. In F 2 (1mg?kg -1 ) group, the serum CK MB LDH HBDH concentration was lowered significantly (vs I/R group P