A cellular based model of the myogenic response in isolated rat cerebral arteries

This study is concerned with the development of an integrated multiple compartment model of the isolated cerebral artery in the rat. The smooth muscle/arterial wall complex is an important component of the circulatory model and serves as an "vasomotor organ", which provides the myogenic mechanism. We have focused on this myogenic mechanism and have developed a model of the electrophysiological, contractile and mechanical characteristics of the single smooth muscle cell. This cell model is used to interrelate the topics of arterial wall stress, changes in transmembrane potential, intracellular [Ca²⁺]_i concentration and smooth muscle contraction. Moreover, the small cell model is embedded in a larger arterial wall model, which converts contractile activity into changes in lumen diameter. The complete model is used to provide biophysically based explanations of the myogenic mechanisms underlying the autoregulation of cerebral blood flow.