muscular layer of stomach(redirected from tunica muscularis gastrica)
muscular layer of stomach[TA]
muscular tunic of the stomach, consisting of smooth muscles arranged in three fairly well-defined layers: an outer longitudinal layer, continuous with that of the esophagus but dividing at the cardia into two bands that run along the greater and lesser curvatures, leaving the middle areas of the anterior and posterior walls devoid of longitudinal fibers, and then coalescing in the pyloric region into a complete layer that is continuous with the longitudinal coat of the duodenum. The middle circular layer is most complete and strongest, continuous with the circular layer of the esophagus at the cardia; it thickens progressively toward the pylorus, ultimately forming the muscular ring of the pyloric sphincter. The inner, oblique layer is unique to the stomach and is most strongly developed in the fundic region and absent along the lesser curvature. This absence contributes to the formation of the "gastric canal."