Intestinal membrane

The intestinal membrane, primarily represented by the brush border membrane of enterocytes, is a semi-permeable barrier essential for nutrient uptake and immune surveillance (NIH, 2023). It is not a single molecular entity but a complex assembly of lipids and proteins, including various transporters such as SGLT1 and GLUT5, as well as digestive enzymes like lactase (StatPearls, 2023). In drug development, the intestinal membrane is the principal site of oral bioavailability, where the interplay between passive diffusion and active efflux, mediated by proteins like P-glycoprotein, determines systemic drug levels (PubMed, 2014). Pathological changes to this membrane, such as increased paracellular permeability or 'leaky gut,' are implicated in systemic inflammation and autoimmune conditions like Celiac disease (NCBI, 2022). Consequently, while it is a physiological structure rather than a discrete therapeutic target, its integrity and the function of its constituent proteins are central to treating malabsorption and inflammatory bowel disorders.

Other names

Intestinal brush border membraneIntestinal mucosaEnteric membraneIntestinal epithelial barrierApical membrane of enterocytes

Drugs interact with the intestinal membrane by binding to specific membrane-bound receptors (e.g., Guanylate cyclase-C), inhibiting apical transporters (e.g., NPC1L1), or utilizing passive and active transport mechanisms to achieve systemic absorption.