ABSTRACT
Objective To explore the role of EphB4 in proliferation of glioma cells. Methods The mRNA and protein expressions of EphB4 were detected using RT-PCR, immunochemistry, and Western-blot, respectively. EphB4 siRNA was synthesized and transfected into U251 cells using Lipofectamine 2000. Glioma cell proliferation, apoptosis, and invasion were determined by MTT assay, TUNEL and transwell experiment, respectively. Results The expression (P<0.05) and proliferation of EphB4 were obviously decreased in U251 transfected with EphB4 siRNA and the proliferation was further decreased with the increased concetrations of siRNA. Compared with U251 group and siRNASCR group, EphB4 siRNA at different concentrations (25, 50 or 100 nmol/L) significantly reduced the invasion ability of cells and increased the number of apoptotic cells (P<0.05). Conclusions EphB4 plays an important role in the regulation of glioma cell proliferation, apoptosis and invasion.
ABSTRACT
AIM: The purpose of the present study was to detect intracellular Ca 2+ changes in living brain slices during focal cerebral ischemia/reperfusion (I/R) and reveal the role of intracellular Ca 2+ in the cerebral I/R injury. METHODS: The model of focal cerebral I/R was established in rats by reversible inserting a nylon thread, and dynamic change of intracellular Ca 2+ in brain slices was determined using laser confocal imaging system. RESULTS: ① Ca 2+ gradually enhanced with increase in ischemic time in cortex and striatum. ②At 1 h ischemia/ 10 min reperfusion, Ca 2+ increased significantly in striatum, but Ca 2+ decreased at 3 h reperfusion compared with 10 min reperfusion. ③ Ca 2+ markedly enhanced at 6 h ischemia compared with 1 h ischemia, and after 3 h reperfusion Ca 2+ decreased, but was still higher than that in sham-operation group. ④The striatum is more sensitive than cortex to ischemia/reperfusion. CONCLUSION: Ca 2+ overload in the area of cortex and striatum may play an important role in cerebral ischemia/reperfusion injury in rats.