The esophageal secretions are entirely mucous in character and
principally provide lubrication for swallowing. The main body of the esophagus
is lined with many simple mucous glands.
At the gastric end and to a lesserextent in the initial portion of the esophagus,
there are also many compound mucous
glands. The mucus secreted by the compound glands in the upper esopha-gus
prevents mucosal excoriation by newly entering food, whereas the compound
glands located near the esophagogastric junction protect the esophageal wall
from digestion by acidic gastric juices that often reflux from the stomach back
into the lower esophagus. Despite this protection, a peptic ulcer at times can
still occur at the gastric end of the esophagus.