Without the blue and red fluorescent colours that have been used to label these blood vessels, this entwined pair would be difficult to tell apart. Arteries (red) and veins (blue) are both built to transport blood, but they are designed to do different jobs. While arteries have muscular walls to withstand high blood pressure and transport oxygen laden blood from the heart, veins have thin walls and ‘inner tubes’ with a larger bore to transport blood carrying waste products and carbon dioxide away for disposal. Microscopic branches of veins and arteries meet deep inside tissues. If this microcirculation becomes damaged, tissue is starved of vital oxygen forcing new vessel branches to grow (a process called angiogenesis). Scientists are now using these contrasting colours to track new vessel growth as it happens in live animals, providing them with a clearer picture of how chronic inflammatory disorders such as arthritis develop.
Written by Caroline Cross
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