Gastrointestinal (GI) physiology is the study and treatment of the digestive tract, with a focus on its physical functions. This area of medical practice includes evaluating patients with suspected GI tract disorders and providing appropriate treatment for patients with conditions like diverticulitis or Crohn's disease. Practitioners in this area of medicine are usually gastroenterologists, specialists in the care of the stomach and gut.
The gastrointestinal tract utilizes a number of different systems to accomplish the goal of processing food. This includes motility, or the movements of the gut to force foods through, as well as secreting various compounds to assist with digestion and uptake of necessary nutrients. It also includes interactions between the circulatory system and the gut to supply it with oxygen and pick up nutrients as they metabolize in the intestines. Gastrointestinal physiology is a study of the whole system from mouth to anus.
A number of conditions can involve the GI tract. Patients may develop infections and inflammation, ulcerations, tumors, and other types of injuries in response to a variety of environmental pressures. Pharmaceutical companies have to understand how gastrointestinal physiology works in order to develop effective medications. Enteric coatings on medications to slow absorption rely on mechanisms in the gut, as do things like the structure of molecules in medications to make sure they can pass through the intestinal lining to reach the bloodstream.
This system also connects with the circulatory system as well as structures like the liver, pancreas, and gallbladder. Gastrointestinal physiology includes an understanding of these systems and how they interact with the GI tract. It can be necessary to treat disorders like gallstones that lead to digestive disorders, or to determine how toxins reach the liver after traveling through the intestines.
Specialists in gastrointestinal physiology can be involved directly in patient care or may conduct research. Researchers work on the development of new diagnostic tools, medications, and treatment protocols. They can conduct clinical trials to test their medications as well as participate in activities like the study of new microorganisms to determine how best to tackle them when they show up in patients.
Gastrointestinal physiology is also highly variable in different species. Horses and humans, for instance, digest and metabolize their food differently. Specialists may focus on a particular species to provide the best medical care and nutrition. This work can include the study of some rather exotic and unusual approaches to digestion; starfish, for example, eat by regurgitating their stomachs and engulfing their prey.