Frequency distribution function of red blood cell velocities in single capillaries of the rat cerebral cortex using intravital laser-scanning confocal microscopy with high-speed camera
Artigo
em Inglês
| IMSEAR
| ID: sea-129936
ABSTRACT
Background:
Brain metabolism depends largely on oxygen and therefore constant delivery of oxygen to the brain is more important than to any other organ. Previously we reported a newly developed method to automatically calculate red blood cell (RBC) flow and its temporal modulations at the layer 1 of the rat cerebral cortex.Objective:
To examine a general tendency of frame-rate dependency of RBC velocities and heterogeneity of RBC movements in single capillaries identified by fluorescein isothiocyanate (FITC)-dextran staining.Methods:
In urethane-anesthetized rats with a closed cranial window, intravenously administered FITC-labeled RBCs were traced at 125, 250 or 500 frames/s (fps) with a laser-scanning confocal fluorescence microscope and their velocities were automatically calculated with home-made software KEIO-IS2.Results:
RBC velocities in single capillaries were not constant but variable, and were dependent on frame rate, with average values of 0.85 ± 0.43 mm/s at 125 fps, 1.34 ± 0.73 mm/s at 250 fps, and 2.05¬1.59 mm/s at 500 fps. When all capillary RBCs were plotted against their velocities (frequency distribution function of RBC velocities), RBC velocities were clustered at around 1.0 mm/s, smearing at higher velocities up to 9.4 mm/s. High RBC velocity was only detected from frame analysis with high frame rates since such high-flow RBCs were uncounted at low frame rates. RBC velocities higher than 6.5 mm/s were statistically significantly outlined from the main population (p \< 0.01). Such a group of capillaries was considered to belong to thoroughfare channels, although their diameter was almost the same as that of ordinary ones.Conclusion:
Extra-high flow capillaries are confirmed in the cerebral cortex and these may be thoroughfare channels or non-nutritional capillaries carrying 42% of the blood in reserve.
Texto completo:
DisponíveL
Índice:
IMSEAR (Sudeste Asiático)
Tipo de estudo:
Estudo prognóstico
Idioma:
Inglês
Ano de publicação:
2010
Tipo de documento:
Artigo
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