Beschreibung:
<jats:sec><jats:label /><jats:p>The formation of functional collaterals from pre‐existing microvessels is an important mechanism to maintain tissue perfusion after vessel obstruction. Here, a previously developed model simulation of inner vessel diameter adaptation in microvascular networks was used to study mechanisms underlying collateralization and arteriogenesis. Changes in hemodynamic and metabolic stimuli after arteriolar occlusion, elicited diameter adaptation and the resulting redistribution of blood flow were analyzed. Results showed that collateral flow pathways were formed including transformation of capillaries and venules to larger arterioles, and partial flow reversal. Initially hypoxic tissue regions (PO2 < 1 mmHg) regained an adequate oxygen level (post‐/pre‐occlusion PO2 = 1.05, Median). Diameter increase in developing collaterals was primarily evoked by: hemodynamic stimuli in the arteriolar portion, hemodynamic and conducted metabolic stimuli in the mid‐section, and local metabolic stimuli close to the capillary beds. Thus, the relative impact of metabolic signals decreases with growing distance from the capillaries downstream of the occlusion site, whereas that of hemodynamic and conducted signals increases.</jats:p></jats:sec>