A Model of Electromechanical Coupling in the Small Intestine - Multiscale Computer Modeling in Biomechanics and Biomedical Engineering - page 176

A Model of Electromechanical Coupling
in the Small Intestine

Peng Du, Jeelean Lim and Leo K. Cheng

Abstract The motility of the intestines is partly governed by a bioelectrical
activity termed intestinal slow wave activity; however, the dynamics of the
electromechanical relationship have remained poorly defined. With the recent
advances in continuum-based multi-scale modeling techniques, we present a
modeling framework to investigate the electromechanical coupling in a segment of
small intestine. The overall modeling framework included three parts: (i) an
anatomical model describing the geometry and makeup of the smooth muscle
fibers; (ii) an electrical model describing the slow wave propagation; and (iii) a
mechanical model describing the active and passive tension laws during con-
traction. The resultant intraluminal pressure was approximated using Lamé's
thick-walled cylinder equation. This modeling framework demonstrates the
potential to be used in investigating the effects of intestinal slow wave dys-
rhythmias on the motility of the small intestine, and may be extended in the future
to incorporate additional regulatory factors and pathways.

1 Introduction

Digestion of food and absorption of nutrients are two important aspects to main-
taining the normal physiological functions of the body. Under the normal cir-
cumstances, the food we eat is moved through a long and convoluted muscular
tubular organ called the gastrointestinal tract. The key physiological function of
the gastrointestinal tract is the uptake of nutrients and water that are necessary for

P. Du ( ) J. Lim L. K. Cheng

Auckland Bioengineering Institute, The University of Auckland,
Auckland, New Zealand
e-mail: [e-mail]

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