Objective To explore the different methods of decoloration for immunohistochemical HE slides,and their influence on tissue antigen expression.Methods Antigen retrieval solution (EDTA or citric acid solution) was used in immunohistochemistry to decolor HE slides,and was compared with the method of hydrochloric acid solution decoloration in normal temperature.Results Antigen heat retrieval decolors completely.Compared with other methods,it has shorter decoloration time (1 ～ 2min),more than 90％ of completely decoloration rate,the difference was significant(x2 =27.6,23.9,all P ＜ 0.01).Meanwhile,the method dose not damage slides,and the immunohistoehemical results are exact,without background coloring and unusual coloring,antigen expression rate and intensity are high.Conclusion Antigen heat retrieval decoloration not only simplifies the coloration process,but also protects tissue antigen activity better.It is the preferable method of decoloration and protecting antigen resource,which possesses some practical value in the pathology diagnosis.

AIM: To observe the change of subunit of NADPH oxidation enzyme complex nox - 1 protein in cardiocyte hypoxia - reoxygenation injury and the role of cardiotrophin -1.METHODS: Cardiomyocytes from the hearts of 1 -3 d old neonatal rats were prepared by a modified method. Five groups were included in the study: control; hypoxia/ reoxygenation; hypoxia/reoxygenation + CT - 1; CT - 1 + hypoxia/reoxygenation + LY294002 (PIK3/Akt inhibitor) ; CT -1 + hypoxia/reoxygenation + PD98059 (ERK inhibitor) ; CT - 1 + hypoxia/reoxygenation + DMSO. The concentration of CT -1 was 10 μg/L. The survival rate of myocytes was evaluated by MTS method. Apoptosis, mitochondrial permeability transition pore ( △ψm) and reactive oxygen species ( ROS) were detected by flow cytometry. Nox - 1 protein was determined by Western blotting. RESULTS: Apoptosis of cardiomyocytes and the level of ROS (19.7% ±1.4% vs 2.1% ± 0.5% , 14.07% ± 1.25% vs 3.54% ± 0.86% , P < 0.05 ) increased markedly after hypoxia/reoxygenation, but cardio-myocyte survival rate and the level of△ψm (40.55% ±4.25% vs 86.28% ±7.15% , P <0.01) decreased significantly. The expression of nox - 1 protein was upregulated markedly. With CT - 1 intervention, cardiomyocyte survival rate increased markedly, apoptosis, both ROS and expression of nox - 1 protein reduced significantly. The level of△ψm increased obviously. The effect of CT - 1 was inhibited by LY294002.No significant effect was observed on cells survival in DMSO group, which confirmed that LY294002 was specifically involved in blocking the protective effect of CT - 1.CONCLUSION : The expression of subunit of NADPH oxidation enzyme complex nox - 1 protein is upregulated markedly in cardiocyte hypoxia - reoxygenation injury.CT - 1 protects cardiac cells against hypoxia - reoxygenation injury by downregulating the expression of nox -1 protein to decrease the level of ROS.

Objective To study the effect of Cardiotrophin-1 (CT-1) on cardiocyte hypoxia-reoxygenation injury,and to investigate the signaling pathways involved in the protective effect. Method This study was carried out in Key Lab of Molecular Medicine in Jiangxi Province. Cardiomyocytes from the hearts of 2-day-old Sprague-Dawley neonatal rats were prepared by a modified method. Five groups were included in the study. Group (ⅰ): control, Group (ⅱ): hypoxia/reoxygeuation, Group (ⅲ): hypoxia / reoxygenation + CT-1, Group (iv) : CT- 1 + hypoxia/ reoxygenation + LY294002 (PIK3/Akt inhibitor), Group (ⅴ): CT-1 + hypoxia / reoxygenation +DMSO. The concentration of CT-1 was 10 ng/mL. Myocytes survival rote was evaluated by MTS method, apopto-sis, mitochondrial permeability transition pore (△ψm) and reactive oxygen species(ROS) were detected by flow cy-tometer, phosphorylased GSK-3β and PI3K protein by western blotting. Analysis of variance and q test as statistical methods was used to analyze the data. Results Cardiomyocyte apoptosis and ROS increased markedly after hy-poxia/reoxygenation,but cardiomyocyte survival rate and the level of △ψm [(40.55±4.25) vs. (86.28±7.15), P < 0.01]decreased significantly. With CT-1 intervention, cardiomyocyte survival rate increased markedly (87%),apoptosis and ROS reduced significantly. The level of △ψm increased, the level of phosphorylased GSK-3β and phosphorylased PI3K protein obviously increased. The effect of CT-1 was inhibited by LY294002, but no significant effect was observed on ceils survival in DMSO group, which confirmed that LY294002 specifically in-volved blocking the protective effect of CT-1. Conclusions CT-1 can protect cardiac cells against hypoxia- reoxy-genation injury, these effects are dependent upon its ability to activate the PI3K/GSK-3β pathway.