Describe the functions of the following components of gastric juice: Hydrochloric acid, Pepsinogen, Pepsin, Intrinsic factor.
Why don’t the components of gastric juice damage the wall of the stomach in the absence of a H. pylori infection?
Why don’t most other types of bacteria produce ulcers?

Case Study
Roger, a sixty-four year old retail store manager, had recently been waking up in the middle of the night and experiencing during the middle of the day abdominal pain. This was happening on a regular basis. He decided to consult a physician.

The doctor noted that Roger seemed fine other than his stomach discomfort.

Roger was referred to a specialist in internal medicine and had a procedure called an endoscopy. The endoscopy was performed at a hospital. During the procedure, a long, thin tube was inserted into Rogers’s mouth and directed into his digestive tract. The end of the tube was equipped with a light source and a small camera which allowed the doctor to observe the interior of Roger’s stomach. The endoscope was also equipped with a small claw-like structure that the doctor could use in order to obtain a small tissue sample from the lining of Roger’s stomach, if needed.

The endoscopy revealed that Roger had a peptic ulcer. Analysis of a tissue sample taken from the site showed that Roger had an infection that was caused by Helicobacter pylori bacteria. Roger was given prescriptions for two different antibiotics and a medication that would decrease the secretion of stomach acid. Roger scheduled a return appointment for another endoscopy procedure in 6 months.