Gastro Intestinal Diseases
This is probably the most common stress-induced disorder today. Anyone who is prone to tension is a potential patient. This disorder is an excellent example of how Western medicine and yoga can work together. A good deal is known about its mechanisms and management.
Cells in the gastric lining secrete acid. There is a chemical pump mechanism that makes for acid flow. Multiple factors influence this secretion: chemical, neural and mental. Gastrin, present in one of the regulatory peptides, stimulates acid flow. This is also present in the duodenal mucosa. Histamine is a chemical present in the gastric mucosa. This also stimulates acid flow by binding to certain receptors, called H2 receptors. Food in the stomach, principally the protein content, stimulates release of acid. Other substances like alcohol, non-steroidal anti-inflammatory drugs like aspirin, caffeine and oral calcium also stimulate acid flow.
Inhibition of acid flow can occur by other chemicals present in the antral mucosa. Somatostatin is one such chemical. Fat in the duodenum also inhibits acid flow. Stimulation of the vagus nerve is responsible for acid flow.
Pepsinogen is an enzyme in the stomach responsible for the formation of pepsin. Both acid and pepsin can corrode the gastric mucosa. Secretion of mucus is a potent inhibitor of the corrosive effects. Bicarbonate ion secreted from the gastric mucosa is another. Once acid is secreted it cannot flow back into the cells as there is an effective barrier to this back flow. If this barrier is broken, cellular injury may result. Maintenance of normal mucosal blood flow is an important component of mucosal resistance to acid injury.