Strain distribution in small blood vessels with zero-stress state taken into consideration

Y. C. Fung*, S. Q. Liu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

109 Scopus citations


The active and passive deformation of a blood vessel is related to the stress in it. Any analysis of stress and strain must begin with the zero- stress state. Recent reports on large blood vessels such as the aorta, pulmonary arteries, and vena cava have shown that, at zero-stress state, blood vessels are not tubes, but opens sectors. This report presents data on the zero-stress state of small blood vessels with lumen diameters down to ~50 μm. Zero-stress state of a vessel was obtained by cutting the vessel into rings and then the rings into sectors; each sector is characterized by an opening angle, α. In rat ileal and plantar arterioles, the opening angles are in the order of 100-250°; those in the venules are in the order of 50- 100°. The effect of norepinephrine on the opening angle α is minor; it decreases α of the superior mesenteric artery, and increases α of the ileocecocolic and ileal arteries. EDTA has little effect on α of arteries >100 μm in diameter, but decreases α of arteries <100 μm. The physiological meaning of the opening angle is demonstrated in terms of the residual strains in a vessel at the no-load state and homeostatic strains at normal blood pressure. The strains in real vessels are compared with those in hypothetical vessels having an opening angle of zero. It is shown that ignoring the opening angle will cause a large error in strain evaluation. Thus it appears that we must take the opening angle into consideration in studying those physiological problems in which the strains are important, e.g., the function of vascular smooth muscle cells.

Original languageEnglish (US)
Pages (from-to)H544-H552
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Issue number2 31-2
StatePublished - 1992


  • arterioles
  • homeostatic state
  • ileal
  • ileocecocolic
  • iliac
  • medial plantar
  • mesenteric
  • no-load state
  • opening angle
  • pulmonary arteries
  • residual strain
  • saphenous
  • stress
  • venules

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Strain distribution in small blood vessels with zero-stress state taken into consideration'. Together they form a unique fingerprint.

Cite this