OBJECTIVETo 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.

METHODSThe 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.

RESULTSWe 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.

CONCLUSIONThe 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.