Abstract
Objective: A theoretical model is used to analyze combinations of RBC-derived and wall-derived (RBC-independent) mechanisms for metabolic blood flow regulation, with regard to their oxygen transport properties. Methods: Heterogeneous microvascular network structures are derived from observations in rat mesentery and hamster cremaster. The effectiveness of metabolic blood flow regulation using combinations of RBC-dependent and RBC-independent mechanisms is simulated in these networks under conditions of reduced oxygen delivery and increased oxygen demand. Results: Metabolic regulation by a wall-derived mechanism results in higher predicted total blood flow rate and number of flowing vessels, and lower tissue hypoxic fraction, than regulation by combinations of RBC-derived and wall-derived signals. However, a combination of RBC-derived and wall-derived signals results in a higher predicted median tissue PO2 than either mechanism acting alone. Conclusions: Model results suggest complementary roles for RBC-derived and wall-derived mechanisms of metabolic flow regulation, with the wall-derived mechanism responsible for avoiding hypoxia, and the RBC-derived mechanism responsible for maintaining PO2 levels high enough for optimal tissue function.
Original language | English (US) |
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Article number | e12690 |
Journal | Microcirculation |
Volume | 28 |
Issue number | 5 |
DOIs | |
State | Published - Jul 2021 |
Keywords
- hematocrit
- hemodilution
- microvascular networks
- oxygen transport
- theoretical model
- vascular tone
ASJC Scopus subject areas
- Physiology
- Molecular Biology
- Cardiology and Cardiovascular Medicine
- Physiology (medical)