What is the function of muscularis externa in stomach?

The muscularis externa is the outermost layer of the stomach wall. It is composed of three layers of smooth muscle fibres:

* An outer longitudinal layer

* A middle circular layer

* An inner oblique layer

The muscularis externa functions to:

* Mix and churn the food in the stomach, facilitating digestion

* Propel the food through the stomach and into the duodenum, the first part of the small intestine

The muscularis externa is innervated by the autonomic nervous system. The vagus nerve stimulates the muscularis externa to contract, while the sympathetic nervous system inhibits its contractions.