Gastrointestinal Anatomy And Physiology: The Es... -

These are extremely dilated submucosal veins in the lower third of the esophagus, usually caused by portal hypertension (often due to liver cirrhosis). They are prone to rupture and can cause life-threatening hemorrhage.

As the peristaltic wave approaches the end of the esophagus, the LES relaxes. This relaxation is mediated by the vagus nerve and neurochemical transmitters like nitric oxide and vasoactive intestinal peptide. Once the food passes into the stomach, the LES constricts again to maintain a high-pressure barrier against gastric acid. Clinical Significance Gastrointestinal Anatomy and Physiology: The Es...

The primary physiological function of the esophagus is deglutition, or swallowing. This is a complex process categorized into three phases: These are extremely dilated submucosal veins in the