Secretory transport

Aungst, B. J. Nguyen, N. H. Bulgarelli, J. P. Oates-Lenz, K. The influence of donor and reservoir additives on Caco-2 permeability and secretory transport of HIV protease inhibitors and other lipophilic compounds, Pharm. Res. 17, 1175-1180 (2000). 

Aungst, B. J. and H. Saitoh. Intestinal absorption barriers and transport mechanisms, including secretory transport, for a cyclic peptide, fibrinogen antagonist. Pharm. Res. 1996, 33, 114-119. 

Different food components (e.g., fruit extracts) and commonly used pharmaceutical excipients (e.g., Tween 80) can interfere with secretory transport systems, leading to drug-food interactions [31, 43, 46, 167], As for CYPs, inhibition and induction of efflux transporters have been reported as possible... 

P-gp substrates, it does not quantify the functional activity of P-gp and furthermore cannot be used to understand how P-gp affects absorptive or secretory transport... 

Troutman MD, Thakker DR. Efflux ratio cannot assess P-glycoprotein-mediated attenuation of absorptive transport asymmetric effect of P-glycoprotein on absorptive and secretory transport across Caco-2 cell monolayers. Pharm Res 2003 20(8) 1200-1209. 

The surface of the nasal cavity is approximately 150 cm. Inside the cavity, the mucosa is covered with the ciliary epithelium. The ciliary activity is the driving force of the secretory transport in the nose. Approximately 1 L of mucus is transported from the anterior part to the posterior part of the nose per day. The mucus in the rear of the cavity is removed by swallowing. The function of the ciliary activity is to remove any particles that are trapped on the mucus blanket during inhalation. It takes approximately 20-30 min for the whole mucus layer to be renewed. 

Aungst BJ, Nguyen NH, BulgarelliJP, and Oates-Lenz K. The Influence of Donor and Reservoir Additives on Caco-2 Permeability and Secretory Transport of HIV Protease Inhibitors and Other Lipophilic Compounds. Pharm Res 2000 17 1175-1180. 

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