Endoscopic measurement method of smooth muscle contractile properties in vivo by electrical stimulation

In order to understand the mechanism of gastric motility, this paper presents a new approach to measure the principal direction of smooth muscle contraction in vivo and analyzes the difference of muscle contraction force by electrical stimulation between in vitro and in vivo for the same porcine stomach region. In both in vitro and in vivo experiments, the electric stimulation was a square wave with a current of 99 mA and a frequency of 99 Hz. As a result of the experiment, contraction force of stomach muscle was measured about 60 times more in vivo condition than in vitro condition, and this result suggests that muscle tissue in vivo has larger energy.