My research focuses on the physiological and pathophysiological regulation of coronary and retinal microcirculation. In the circulatory system, the amount of blood delivered to each tissue can be regulated by the activity of arterial microvessels (<100 m in diameter). Changes in vascular tone, i.e., constriction or dilation of these microvessels, will decrease or increase blood supply to the tissue, respectively. However, the mechanisms involved in the regulation of vascular tone are not completely understood. Our current research focuses on the regulation of microvascular tone by hemodynamic (e.g., pressure and shear stress), metabolic (e.g., adenosine, osmolarity, K+, pH, pO2) and neural (adrenergic receptors) factors. To have an integrative view on the flow regulation, this basic information are reconstructed using mathematical model and computer simulation technology. This research provides a basic foundation critical to our understanding of blood flow regulation in the microvascular network under normal and disease states.