Describe the hormonal response to a meal.
For a good answer candidates were expected to have an integrated knowledge of
gastrointestinal physiology. Gut function is regulated by the enteric nervous system and by paracrine and endocrine hormones released by hormone secreting cells in the mucosa of the gut (enteroendocrine cells). These cells secrete hormones in response to neural innervation or in response to triggers associated with ingested food. Gut functions influenced include secretion, digestion, absorption and motility. The endocrine system also has an important role in the handling of nutrients following absorption and some mention of insulin was required.
|Cephalic phase: anticipatory neuroendocrine responses|
|Anticipation of food;
thoughts about food;
sensory characteristics of food (taste, smell, mouthfeel, mastication, appearance of food)
|Gastric phase: reactive gastric hormonal and local reflex responses|
Pharyngeal sensation of swallowing;
|Intestinal phase: endocrine modulation of gastric and biliary activity by the duodenum|
|Stimulated by the volume, osmolality and chemical composition of the chyme entering the duodenum||
|Absorptive phase: endocrine response to absorbed nutrients|
|Stimulated by increased blood glucose||
Pandol, Stephen J. "Integrated response to a meal." Journal of Parenteral and Enteral Nutrition 32.5 (2008): 564-566.
Camilleri, Michael. "Integrated upper gastrointestinal response to food intake." Gastroenterology 131.2 (2006): 640-658.
Livovsky, Dan M., Teorora Pribic, and Fernando Azpiroz. "Food, eating, and the gastrointestinal tract." Nutrients 12.4 (2020): 986.
Raybould, H. E., S. J. Pandol, and H. Yee. "The integrated responses of the gastrointestinal tract and liver to a meal." Textbook of Gastroenterology, (2003): 2-12.
Lim, Robert KS, A. C. Ivy, and J. E. McCarthy. "Contributions to the physiology of gastric secretion. I: gastric secretion by local (mechanical and chemical) stimulation." Quarterly Journal of Experimental Physiology: Translation and Integration 15.1 (1925): 13-53.
Power, Michael L., and Jay Schulkin. "Anticipatory physiological regulation in feeding biology: cephalic phase responses." Appetite 50.2-3 (2008): 194-206.