A Computational Study of the Effect of Vasomotion on Oxygen Transport from Capillary Networks

✍ Scribed by DANIEL GOLDMAN; ALEKSANDER S. POPEL

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 343 KB
• Volume: 209
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.2000.2254

✦ Synopsis

The objective of this study was to investigate the e!ect of arteriolar vasomotion on oxygen transport from capillary networks. A computational model was used to calculate blood #ow and oxygen transport from a simulated network of striated muscle capillaries. For varying tissue oxygen consumption rates, the importance of the frequency and amplitude of vasomotion-induced blood #ow oscillations was studied. The e!ect of myoglobin on oxygen delivery during vasomotion was also examined. In the absence of myoglobin, it was found that when consumption is high enough to produce regions of hypoxia under steady #ow conditions, vasomotion-induced #ow oscillations can signi"cantly increase tissue oxygenation and decrease oxygen transport heterogeneity. The largest e!ect was seen for low-frequency, highamplitude oscillations (1.5}3 cycles min, 90% of steady-state velocity). By contrast, at physiological tissue myoglobin concentrations, vasomotion did not improve tissue oxygenation. This unexpected "nding is due to the bu!ering e!ect of myoglobin, suggesting that in highly aerobic muscles short-term storage of oxygen is more important than the possibility of increasing transport through vasomotion.