Dopamine and Gastrointestinal Motility

Dopamine (DA) plays an important role in regulating gastrointestinal (GI) motility function, from the esophagus to the colon. In this chapter, we focus on the role of DA in regulating esophageal, gastric, and intestinal motility under physiological processes. We describe the effect of DA on contractile activity of the lower esophageal sphincter (LES), esophageal peristalsis, gastric myoelectricity, intragastric pressure, antral motility, gastric emptying, antroduodenal coordination, intestinal motility, and GI transit time. DA antagonists have prokinetic effect on GI tract. We review the effect of DA antagonists on gastroparesis and gastroesophageal reflux, antroduodenal coordination, and colonic motility disorders. We discuss the possible mode of DA in GI motility regulation, via acting on smooth muscle cells, intrinsic neurons, and extrinsic neurons. In pathological states, such as Parkinson’s disease (PD), we summarize the symptoms and underlying mechanism of abnormal GI motility in PD patients. Furthermore, we review GI motility function in several PD animal models.