Page 557 - Atlas of Histology with Functional Correlations

FIGURE 14.6 ■ Lower esophageal wall (transverse section). Stain: Mallory-
Azan. ×30.

FUNCTIONAL CORRELATIONS 14.1 ■

Esophagus

The major function of the esophagus is to convey liquids or chewed food
(bolus) from the oral cavity to the stomach. For this function, the lumen of
the esophagus is lined with a protective nonkeratinized stratified squamous

epithelium. Aiding in this function are esophageal glands in lamina propria.
The esophageal cardiac glands are in the lamina propria of the upper and
lower regions of the esophagus and exhibit morphology similar to those

found in the cardia of the stomach, where the esophagus terminates.
Esophageal glands proper are located in the submucosa. Both types of glands
produce mucus to lubricate the esophageal lumen and protect it during the
passage of ingested solid material. The swallowed material is moved from
one end of the esophagus to the other by strong muscular contractions called

peristalsis. At the lower end of the esophagus, a muscular gastroesophageal
sphincter constricts the lumen and prevents the regurgitation of swallowed
material into the esophagus.

FIGURE 14.7 | Esophageal–Stomach Junction

At its terminal end, the esophagus joins the stomach and forms the esophageal–
stomach junction. The nonkeratinized stratified squamous epithelium (1) of the

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