Carrier-mediated transport oral mucosa

Utoguchi N, Watanabe Y, Suzuki T, Maehara J, Matsumoto Y, Matsumoto M (1997) Carrier-mediated transport of monocarboxylic acids in primary cultured epithelial cells from rabbit oral mucosa. Pharm Res 14 320-324... 

It has also been suggested that the oral mucosa contains active or carrier-mediated systems for small molecules such as mono-saccharides and amino acids. However, these processes have not been fully characterized in terms of location, transport capacity or specificity. 

Dietary riboflavin is present mostly as a phosphate, which is rapidly hydrolyzed before absorption in the duodenum.In humans, the rapid, saturable absorption of riboflavin following an oral dose suggests that it is transported by a carrier-mediated pathway located predominantly in duodenal enterocytes. The process may be sodium-dependent. Bile salts enhance absorption of riboflavin. Fecal riboflavin is derived from the intestinal mucosa and the intestinal flora. This is the predominant excretory route for the vitamin. 

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