Barrier Function of Gastric Mucus.

Demonstration of a pH gradient across mucus adherent to rabbit gastric mucosa: evidence for a 'mucus-bicarbonate' barrier.

We examined the ability of the mucus layer adherent to isolated pieces of rabbit gastric mucosa to maintain a pH gradient across it. Using antimony microelectrodes, a stable pH gradient was detected from pH 2.31 +/- 0.04 on the luminal side to pH 7.26 +/- 0.15 (n = 22) on the epithelial side of the mucus layer. The gradient was maintained for at least 60 minutes. A metabolic inhibitor, potassiu...

Protective Effects of Gastric Mucus

The gastric mucosa is continuously exposed to many noxious factors and substances. How the gastric mucosa maintains structural integrity and resists auto-digestion by substances such as acid and pepsin puzzled clinicians and investigators for more than 200 years. The gastric epithelium must also resist damage from extrinsic agents, including Helicobacter pylori (H. pylori) and noxious ingestion...

Mechanisms of gastric mucosal protection: a role for the 'mucus-bicarbonate' barrier.

Mucus barrier-triggered disassembly of siRNA nanocarriers.

The mucus overlying mucosal epithelial surfaces presents not only a biological barrier to the penetration of potential pathogens, but also therapeutic modalities including RNAi-based nanocarriers. Movement of nanomedicines across the mucus barriers of the gastrointestinal mucosa is modulated by interactions of the nanomedicine carriers with mucin glycoproteins inside the mucus, potentiated by t...

Interaction of polyacrylates with porcine pepsin and the gastric mucus barrier: a mechanism for mucosal protection.

1. The mechanism of interaction of the polyacrylates, carbopols with the mucus barrier in vivo has been investigated in vitro. 2. Carbopol caused a dramatic increase in the viscosity of porcine gastric mucin solutions that was up to 19-fold greater than that of the sum of the individual polymers. 3. The mucin-carbopol interaction was stable after an initial 30 min period for up to 36 h at 25 de...