The intestines are mainly supplied by the three unpaired branches of the abdominal aortas:
- Coeliac artery
- Superior mesenteric artery
- Inferior mesenteric artery
The coeliac artery emerges immediately after the passage of the aorta through the aortic hiatus of the diaphragm. It divides into a branch to the spleen, the lienal artery, a branch to the stomach, the left gastric artery, and into the common hepatic artery, which somewhat later becomes the right gastric artery.
The superior mesenteric artery supplies the whole small intestine and extends branches up to the middle third of the transverse colon. Up to this point, the innervation is taken over by the vagus nerve (CN X).