Three-Dimensional Multi-Scale Modeling of Electro-Chemomechanical Gastric Smooth Muscle Contraction

Abstract

AbstractThe stomach, to be a J-shaped hollow organ, undergoes large deformations during the digestion of a meal. Hereby, different types of contractions across the stomach wall accomplish different tasks, including the storage, mixing, and transport of ingested food, leading to a complex motility pattern. To coordinate the different gastric contractions, specialized pacemaker cells, so-called interstitial cells of Cajal (ICC), generate electrical slow waves. These slow waves propagate in an electrically-coupled network of ICCs and depolarize neighboring smooth muscle cells. Impaired stomach motility can be caused by a failure of the electrical regulation underlying the activation of gastric smooth muscle contraction, namely gastric dysrhythmias, and can be evoked by any disturbance in the electrical network. Multi-scale models are potential tools to predict gastric motility based on underlying events of ICC network electrophysiology. In the present study, a three-dimensional multi-scale model of the electro-chemomechanical activation of gastric smooth muscle contraction is presented. Additionally, a mechano-electrical feedback mechanism is included. Simulations are performed on a realistic, physiological stomach geometrical model and a postsurgical stomach, studying the effects of a surgical excision on the stomach wall electrophysiology and motility.