Role of O2 in Control of the Coronary Capillary Reserve
Enormous progress has been made in determining the amount, distribution, and control of coronary blood flow, largely through the work of Gregg and those he trained and inspired (5, this entire Symposium). Transport, however, depends not only on flow, but also on diffusion between capillary and tissue. Diffusion is determined by concentrations at the capillary wall, and by the distances to be transversed. Since flow sets concentrations at the capillary, flow and diffusion are interrelated. If diffusion distance is sufficiently long, tissue anoxia can occur at an infinitely large flow rate, whereas if flow is sufficiently low, anoxia can occur at minimum diffusion distance.
KeywordsCoronary Blood Flow Capillary Density Sphincter Muscle Vascular Muscle Contractile Strength
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