Regulation of GI tract Flashcards
Define endocrine
cellular signal which acts on distant cells to exert effects, usually thanks to transportation through blood
Define paracrine
a cellular signal which acts very locally to exert effects, normally thanks to simple diffusion
Define lumen
the bore of a tubular structure in anatomy, think of the insides of your small intestine
Define secretagogue
luminal contents of GI tract which act to activate reecptor or transporters on enteroendocrine cells
Define epithelium
the continuous cell sheets which cover the outer surface of our bodies and lines the cavities, think the length of GI tract
Role of enteroendocrine system
- stimulate secretion
- stimulate emptying
- stimulate growth
- stimulate motility
- act as endocrine, paracrine, or neurocrine signals
Enteroendocrine hormone families
- gastrin
- secretin
- motilin
Where is gastrin expressed
stomach and duodenum
Where is secretin expressed
duodenum and jejunum
Where is CCK expressed
duodenum, jejunum and illeum
Where is GIP expressed
duodenum and jejunum
Where is GLP-1 expressed
illeum and large intestine
Where is GLP-2 expressed
illeum and large intestine
Where is motilin expressed
duodenum and jejunum
Where is ghrelin-secreting cell expressed
stomach, duodenum, jejunum, illeum, large intestine
