Describe the normal pathophysiology of gastric acid stimulation and production. Explain the changes that occur to gastric acid stimulation and production with GERD, PUD, and gastritis disorders.

Parietal cells produce gastric acid in the stomach. They release hydrochloric (HCl) acid and secrete an intrinsic factor that aids vitamin B12 absorption. Positive feedback stimulates the production of HCl when acid conditions are present in stomach. Normal secretion of HCl is controlled by hormones like gastrin, histamine, and somatostatin.

In Gastroesophageal Reflux Disease(GERD), abnormal levels HCl released into the esophagus because of laxity the lower esophageal sphincter muscles. The lining can become inflamed and irritated, leading to heartburn or pain.

Peptic Ulcer Disease is caused by an imbalance of protective and aggressive factors, such as mucus secretion or bicarbonate. These factors can cause ulcers to bleed and abdominal pain.

Gastritis Disorders are characterized by inflammation of the mucosal lining due to infection with Helicobacter Pylori. This leads to a reduction in gastric secretions, including HCl. The result is a decreased ability to digest food, which can lead to malabsorption.