title: The endothelial glycocalyx promotes homogenous blood flow distribution within the microvasculature.
abstract: Many common diseases involve impaired tissue perfusion, and heterogeneous distribution of blood flow in the microvasculature contributes to this pathology. The physiological mechanisms regulating homogeneity/heterogeneity of microvascular perfusion are presently unknown. Using established empirical formulations for blood viscosity modeling in vivo (blood vessels) and in vitro (glass tubes), we showed that the in vivo formulation predicts more homogenous perfusion of microvascular networks at the arteriolar and capillary levels. Next, we showed that the more homogeneous blood flow under simulated in vivo conditions can be explained by changes in red blood cell interactions with the vessel wall. Finally, we demonstrated that the presence of a space-filling, semipermeable layer (such as the endothelial glycocalyx) at the vessel wall can account for the changes of red blood cell interactions with the vessel wall that promote homogenous microvascular perfusion. Collectively, our results indicate that the mechanical properties of the endothelial glycocalyx promote homogeneous microvascular perfusion. Preservation or restoration of normal glycocalyx properties may be a viable strategy for improving tissue perfusion in a variety of diseases.
authors.affiliation: Division of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, Colorado; Department of Medicine, Denver Veterans Affairs Medical Center, Denver, Colorado; Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado;
authors.forename: P Mason
authors.initials: PM
authors.lastname: McClatchey
authors.affiliation: Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado; Division of Cardiology, Department of Pediatrics, Children's Hospital Colorado, Aurora, Colorado; and.
authors.forename: Michal
authors.initials: M
authors.lastname: Schafer
authors.affiliation: Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado; Division of Cardiology, Department of Pediatrics, Children's Hospital Colorado, Aurora, Colorado; and.
authors.forename: Kendall S
authors.initials: KS
authors.lastname: Hunter
authors.affiliation: Division of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, Colorado; Department of Medicine, Denver Veterans Affairs Medical Center, Denver, Colorado; Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado; Center for Women's Health Research, University of Colorado School of Medicine, Aurora, Colorado jane.reusch@ucdenver.edu.
authors.forename: Jane E B
authors.initials: JE
authors.lastname: Reusch
mesh_terms: D001160:Arterioles / Q000033:anatomy & histology / Q000502:physiology*; D001809:Blood Viscosity; D002196:Capillaries / Q000033:anatomy & histology / Q000502:physiology*; D002199:Capillary Permeability; D042783:Endothelial Cells / Q000502:physiology*; D004912:Erythrocytes / Q000502:physiology; D019276:Glycocalyx / Q000502:physiology*; D018056:Hemorheology; D006801:Humans; D008833:Microcirculation; D046210:Microfluidic Analytical Techniques; D008955:Models, Cardiovascular; D012039:Regional Blood Flow
keywords: glycocalyx; microvascular perfusion; oxygen delivery; perfusion heterogeneity