2F44 Development for mapping the flow velocity dynamics with fluorescent imaging techniques

Abstract

The present study was aimed to develop a mapping method for blood flow velocity of the cortical arteries and veins in the anesthetized mice. The cortical region where the skin and skull was removed was continuously imaged with confocal laser scanning fluorescence microscopy at a rate of 20-76 frame per sec, while a small amount of the fluorescent dye (20 μL) was injected through the tail vein. A transit of the dye in the cerebral microcirculation was tracked, and a traveling time and distance of the dye through the vasculature was measured with custom written software to create a velocity map. The result showed a good linear correlation was shown between the flow velocity and a diameter of the vessel in the arteries, but not in the veins. The results demonstrate that the proposed method for mapping of the flow velocity will be a valuable tool to explore the cellular interactions among brain cells, vascular cells, and blood flow velocity in the functioning brains.