Computational modeling of nitric oxide transport and consumption in blood vessels

A two-dimensional, multi-cellular model, that describes the transport and consumption of Nitric oxide (NO) in blood vessels and the surrounding tissue, is developed. Unlike previous models of this system, the model developed here accounts explicitly for the presence of, and interactions among, a population of red blood cells (RBCs) inside the lumen of the blood vessel, and is, therefore, better suited to quantify the transport barriers that reduce the rate of NO consumption in the blood. The model uses experimentally-derived parameters and consists of several sets of partial differential equations (PDEs) that describe the production, diffusion, and consumption of NO in different regions inside and around the vessel. The PDEs are coupled through the boundary conditions that govern the flux and concentration of NO at the interfaces between the different regions. The entire set of PDEs is solved for NO concentration, using efficient finite-element algorithms, and the results are used to assess the contribution of each transport barrier to the overall resistance for NO uptake in the blood.