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Updated: Aug 17, 2026

Non-invasive Assessment of Microvascular and Endothelial Function
Published on: January 29, 2013
Can capillaries increase in length without any increase in the number of endothelial cells?
M P Bonakdar1, P M Barber, H N Newman
1Periodontology Department, Eastman Dental Institute, London, UK.
Abstract:
Generally it is believed that one of the causes of vascular expansion is the increase in length of small capillaries, which in turn is attributed to an increase in the number of endothelial cells. In this report we suggest a new hypothesis for a different mechanism for the increased length of small capillaries, which excludes an increase in the number of endothelial cells. This hypothesis is based upon the possibility of a longitudinal expansion of blood vessels, and has been explained and justified through a series of mathematical examples.
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