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XU Rui ZHANG Yun ZHANG Mei GE Zhi-ming CHEN Wen-qiang LI Xiu-chang CAI Heng ZHU Hui 《园艺学报》2003,19(5):642-644
AIM:To elucidate the relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats (SHR).METHODS:Intracellular free calcium concentrations were measured by Fura 2 methodology and left ventricular function quantitated by cardiac catheterization in 20 SHR aged 10, 22, and 34 weeks and 20 age-matched Wistar-kyoto (WKY) rats.RESULTS:(1) The systolic blood pressure(SBP), intracellular calcium concentrations and left ventricular mass / body weight index (LVM/BW) were significantly higher in all three age groups of SHR than the corresponding groups of WKY; (2) Compared with age-matched WKY groups, the peak left ventricular pressure descending rate(-dp/dtmax) decreased while left ventricular relaxation time constant (τ)increased significantly in SHR aged 22 and 34 weeks. The peak left ventricular pressure ascending rate(dp/dtmax) and the left ventricular contractility index were significantly increased only in the 34 weeks SHR; (3) Intracellular calcium concentrations showed a positive correlation with LVM/BW,SBP,-dp/dtmax and τ(r=0.47-0.83,P<0.01)and a negative correlation with dp/dtmax and the left ventricular contractility index (r=-0.46,P<0.05 and r=-0.81, P<0.01).CONCLUSION:Intracellular calcium overload is one of the potential mechanisms in the induction of left ventricular hypertrophy as well as of systolic and diastolic dysfunction. 相似文献
64.
AIM:The effective antisense sequences targeted VEGF mRNA with computer software would be screened and designed, and effect of them on growth K562 cells and protein expression of VEGF were studied with experiments.METHODS:Seven antisense sequences were selected and synthesized, which consisted of 18-20 deoxynucleotide acid and were modified with phosphorothioate, according to principle of low free energy of overall △G37 Overall. Cell growth was assayed by trypan blue dye exclusion assay and level of VEGF protien in the media was determined by ELISA.RESULTS:Six of seven sequences were capable of inhibing growth of K562 cells and downregulating the VEGF protein expression significantly, compared with Scrambed control group. It was found that there was a close correlation between low level of overall △G37 and antisense effectiveness (r=0.887,P<0.01).CONCLUSION:VEGF mRNA antisense oliogdeoxynucleotides, which were designed by computer software of RNAstructure, were able to inhibit growth of K562 and its protein expression. The VEGF mRNA may be new target attached by drugs. At same time, the computer aided design is useful methods to obtain the effective antisense. 相似文献
65.
AIM:To investigate the effect of cyclophosphamide(CTX) on proliferation and apoptosis of mesangial cells(GMC) of rat in vitro. METHODS:GMC proliferat ion was detected by MTT method,GMC apoptosis was examined by inverted microscopy for phase-contract and fluoroscopy and flow cytometry analysis.The levels of Fas and Bcl-2 were also detected by immunohistology. RESULTS:The proliferation of GMC were inhibited by CTX, methylprednisolone(MP), low molecular weight heparin(LMWH). Apoptosis of GMC was induced by CTX, the apoptosis rate of GMC was 8.2%, and the Fas level was increased. CONCLUSION:CTX could inhibit proliferation and induce apoptosis of GMC possibly by enhancing the Fas level. 相似文献
66.
AIM:To explore the effect of brain ischemia injury on cell proliferation and nestin expression in cortex and subependymal zone (SEZ).METHODS:Using a local brain ischemia model(MCAO), BrdU positive cells of cortex and subependymal zone (SEZ), also nestin positive cells, were observed by immunohistochemistry.RESULTS:BrdU and nestin positive cells in SEZ of MCAO rats were obviously increased. In cortex, only nestin positive cells were observed.CONCLUSION:Neural stem cells in SEZ and cortex were activated after brain ischemia, it may be related with neural recovery after brain ischemia injury. 相似文献
67.
REN Hong-bo LI Zhao-shen XU Guo-ming TU Zheng-xing JIA Yi-tao SHI Xin-gang GONG Yan-fang 《园艺学报》2003,19(7):923-926
AIM:To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) signaling pathway in the Kupffer cells (KCs) production of pro-inflammatory cytokines, tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β), in severe acute pancreatitis (SAP) rats.METHODS:Sprague-Dwaley rats were randomized into three groups:①sham operation rats, ②SAP rats, ③SAP rats given the p38 MAPK inhibitor CNI-1493(10 mg/kg, iv). The SAP model was induced by the bili-pancreatic duct infusion with 5% sterile soduim taurocholate solution. Rats from each group were killed at 12 h after sham operation or SAP and Kupffer cells (KCs) were isolated. The mRNA expressions of TNF-α and IL-1β (by quantitative real-time RT-PCR) and p38 MAPK activity (by Western blot analysis) in KCs were examined. The levels of TNF-α and IL-1β in plasma were determined by ELISA.RESULTS:There was a significant acvitation of p38 MAPK in KCs harvested from SAP rats than those from sham operation rats. SAP also promoted the mRNA expressions of TNF-α and IL-1β in KCs and the plasma levels of TNF-α and IL-1β. These events were significantly inhibited by treatment with CNI-1493.CONCLUSIONS:p38 MAPK activation is one important aspect of the signaling events that may mediate the KCs production of pro-inflammatory cytokines, TNF-α and IL-1β, in SAP rats. The inhibition of the p38 MAPK may be a potential target in the prevention and treatment of SAP. 相似文献
68.
AIM:To investigate the effect of insulin on ox-LDL transferring the THP-1 cells to foam cells and influencing the LPL mRNA expression in THP-1 cells.METHODS:THP-1 cells were incubated with 50 mg/Lox-LDL and insulin at concentrations of 10 mU/L, 100 mU/L, 1 000 mU/L and 10 000 mU/L, respectively. The expression of LPL mRNA in cells was detected by RT-PCR. Lipoprotein lipase of THP-1 cells was presented by no-specific lipase staining. THP-1 cells were stained with oil red O. Accumulation of total cholesterol (TC) in THP-1 cells was determined with oxidase assay.RESULTS:In 100 mU/L、1 000 mU/L、10 000 mU/L insulin groups, LPL mRNA expression increased 2 times, the average cell perilength was longer, the percentage of positive oil red O staining cells was significant higher, the content of cholesterol in THP-1 cells was higher than in ox-LDL control (P<0.05).CONCLUSION:Insulin accelerates transferring of THP-1 cells to foam cell with exposed to ox-LDL because LPL mRNA expression increased in the cells. 相似文献
69.
As an important mediator of allergic inflammation, mast cell tryptase is involved in the in duction of hypersensitivity, infiltration of inflammatory cel s and t issue remodeling in respiratory tract.The effects of tryptase inhibitors on the actions of tryptase show further the potential of tryptase in the pathogenesis of asthma and its inhibitors in the treatment of asthma. 相似文献
70.
AIM: To investigate the effect of IH764-3 on the apoptosis of H2O2-stimulated hepatic stellate cells(HSCs) and the alteration of focal adhesion kinase (FAK). METHODS: The proliferation of HSCs was examined by direct cell count and the apoptosis was determined by Annexin-V/PI labeling, while the morphological change was observed by light microscopy and transmission electron microscopy. In addition, FAK mRNA was detected by RT-PCR. RESULTS: H2O2 promoted the proliferation of HSCs. IH764-3 induced the apoptosis of HSCs in a dose-dependent manner. The HSC apoptotic rates of different groups were 6. 35%,9. 28%,15. 10%,19. 69%,respectively, after treated with different concentrations of IH764-3 for 48 h while H2O2 group showed 2. 30%. In 30 mg/L group, the apoptosis rates were 6. 73%、10. 34%、15. 10% for the indicated time periods(12 h, 24 h, 48 h). In the presence of IH764-3, FAK mRNA decreased. The FAK mRNA reduction began at 2 h after adding IH764-3. CONCLUSION: IH764-3 induced the apoptosis of HSCs. Down-regulating the expression of FAK mRNA may be one of its mechanisms. 相似文献