A Physical Mechanism for Micro-vascular Adaptability

Abstract

Techniques like MOST allow microvascular networks to be mapped with high (and increasing) resolution. However, despite an abundance of new data, little remains known about the physical principles that underlie network wiring. Here we use the zebrafish trunk microvasculature as a model to study the adaptability of microvascular networks to damage. In particular, we use imaging of real embryonic zebrafish and mathematical modeling to show that following amputation of the zebrafish tail, the microvascular network is adapted to locally reroute blood flow through the nearest collateral vessels, increasing both hematocrit and fluid shear stress in those vessels. Shear stress is known to be an effector for vessel growth and repair, and this adaptation has the benefit of also increasing blood supply to regrowing tissues. We go on to look for similar motifs for adaptability in a data set of cortical blood vessels. In addition to revealing the exquisite hydraulic engineering of the zebrafish microvascular network, our results suggest a general organizing principle for microvascular networks.