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A direct method for measuring mouse capillary cortical blood volume using multiphoton laser scanning microscopy.

Pascale Vérant·Raphaël Serduc·Boudewijn Van Der Sanden·Chantal Rémy·Jean-Claude Vial
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Abstract

Knowledge of the blood volume per unit volume of brain tissue is important for understanding brain function in health and disease. We describe a direct method using two-photon laser scanning microscopy to obtain in vivo the local capillary blood volume in the cortex of anesthetized mouse. We infused fluorescent dyes in the circulating blood and imaged the blood vessels, including the capillaries, to a depth of 600 microm below the dura at the brain surface. Capillary cortical blood volume (CCBV) was calculated without any form recognition and segmentation, by normalizing the total fluorescence measured at each depth and integrating the collected intensities all over the stack. Theoretical justifications are presented and numerical simulations were performed to validate this method which was weakly sensitive to background noise. Then, CCBV had been estimated on seven healthy mice between 2%+/-0.3% and 2.4%+/-0.4%. We showed that this measure of CCBV is reproductible and that this method is highly sensitive to the explored zones in the cortex (vessel density and size). This method, which dispenses with form recognition, is rapid and would allow to study in vivo temporal and highly resolute spatial variations of CCBV under different conditions or stimulations.

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AlgorithmsAnimalsBlood VolumeCapillariesCerebral CortexCerebrovascular CirculationComputer SimulationImage Processing, Computer-AssistedMiceMice, NudeMicrocirculationMicroscopy, ConfocalReproducibility of ResultsJournal Article

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Pascale Vérant, Raphaël Serduc, Boudewijn Van Der Sanden, Chantal Rémy, Jean-Claude Vial. 2006-10-25. A direct method for measuring mouse capillary cortical blood volume using multiphoton laser scanning microscopy.. https://doi.org/10.1038/sj.jcbfm.9600415

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