In vivo imaging of blood flow using two-photon laser scanning fluorescent microscopy / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe the three-dimensional distribution of vessels, and to establish a new method for measurement of blood flow velocity in mice cerebral cortex using two-photon laser scanning microscopy and fluorescence probe labeling technique.</p><p><b>METHODS</b>The mouse was made cranial window surgery and injected Texas-Red through tail vein after anesthetized. The three-dimensional imaging of vessel was obtained through z-stack scanning, and blood flow velocity was quantified through line scanning.</p><p><b>RESULTS</b>We could detect vascular distribution for more than 500 µm depth using two-photon microscopy. The velocity of blood flow was (0.59 ± 0.12) mm/s in capillary.</p><p><b>CONCLUSION</b>The method for observing the brain blood flow by two-photon microscopy was established, which could achieve quantification of single vascular blood flow velocity and provide experimental evidence for basic research and medical applications.</p>

Effect of chronic lead exposure on expression of autophagy-associated proteins in rat hippocampus / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of chronic lead exposure on expression of autophagy-associated proteins in rat hippocampus.</p><p><b>METHODS</b>SD rats were randomly divided into three groups: control group was given distilled water, lead-exposed groups were given 0.5 g/L (low-dose) or 2.0 g/L(high-dose) lead acetate solution in drinking water. The rat pups started to drink the lead content water until 60 d maturity. The lead contents in blood and brain samples were analyzed by graphite furnace atomic absorption spectrophotometry. The expressions of Beclin 1, LC3, LAMP2 and cathepsin B proteins were detected by Western blot and immunohistochemistry.</p><p><b>RESULTS</b>Compared with control group, the contents of lead were significantly higher in blood and hippocampus samples in chronic lead-exposed rats (P<0.01). Western blot showed that the expression of Beclin 1 and LC3-II/LC3-I increased significantly in high dose lead-exposed group compared with control group (P<0.05 or P<0.001). The confocal laser immunostaining results demonstrated that increased immunofluorescence staining of cathepsin B in hippocampal neurons compared with control animals.</p><p><b>CONCLUSION</b>The disturbance of autophagy-lysosome signaling molecules might be partially contribute to neurotoxicity of chronic lead exposure.</p>