Search results for "Nutrient absorption"
showing 2 items of 2 documents
Villification: How the Gut Gets Its Villi
2013
Intestinal Villus Formation The intestinal villi are essential elaborations of the lining of the gut that increase the epithelial surface area for nutrient absorption. Shyer et al. (p. 212 , published online 29 August; see the Perspective by Simons ) show that in both the developing human and chick gut, the villi are formed in a step-wise progression, involving the sequential folding of the endoderm into longitudinal ridges, via a zigzag pattern, to finally form individual villi. These changes are established through the differentiation of the smooth muscle layers of the gut, restricting the expansion of the adjacent proliferating and growing endoderm and mesenchyme, generating compressive …
The renin–angiotensin system in gastrointestinal functions
2023
In this chapter, we describe the role played by classical and alternative renin–angiotensin system (RAS) in the physiological regulation of gastrointestinal functions. RAS modulates gut motility and mucosal functions, including secretion, fluid, and nutrient absorption. We focus mainly on the activation of angiotensin II type 1 and 2 receptors located on the smooth muscle and epithelial cells or on the enteric neurons. Few studies indicate that alternative RAS may counteract classical RAS functions. Although data on the enteric RAS system are still scarce, they encourage further investigations in consideration also of a potential involvement in gastrointestinal disorders.