Epithelial transport

Greger, R., Kunzelmann, K., Lohrmann, E. and Hansen, C.P. (1991) In Ionic Basis and Energy Metabolism of Epithelial Transport, Hot aspects from exocrine secretion (Murakami, M., Ed.), pp. 167-170, Kebun Printing, Okazaki. 

N. Wills, L. Reuss, and S. Lewis, eds., Epithelial Transport A Guide to Methods and Experimental Analysis, Chapman Hall, Bury St Edmunds, 1996. 

Artursson, R, Epithelial transport of drugs in cell culture. I A model for studying the passive diffusion of drugs over intestinal absorptive (Caco-2) cells, J. Pharm. Sci. 79, 476-482 (1990). 

R Kinne. Epithelial transport The interplay between ion gradients and cell polarity. In F Alvarado, CH van Os, eds. Ion Gradient-Coupled Transport. Inserm Symposium No. 26. New York Elsevier, 1986, pp 255-264. 

Fig. 11.4. Model for cholinergic signalling in the intestinal mucosa, providing a possible rationale for AChE secretion by parasitic nematodes. ACh released from enteric cholinergic motor neurons stimulates chloride secretion, mucus secretion and Paneth cell exocytosis through muscarinic receptors. Secretory responses may be modulated by mast cell mediators, either directly or via the induction of neural reflex programmes. The role of muscarinic receptor-positive cells in the lamina propria of rats infected with N. brasiliensis is undetermined, as are potential mechanisms of trans-epithelial transport of the enzymes. Adapted from Cooke (1984).

The transporter-mediated uptake of drugs into epithelial cells is emerging as a new trend in biopharmaceutics [6]. Utilization of the intestinal epithelial transporters to facilitate the absorption of drugs or prodrugs appears to be an attractive delivery approach. The purpose of this chapter is to describe the pharmaceutical and medicinal relevances of intestinal transporters. This will provide new knowledge for strategies to enhance intestinal absorption of drugs. 

T. Kai, T. Isami, Y. Kurosaki, T. Nakayama, and T. Kimura. Keratinized epithelial transport of beta-blocking agents. II. Evaluation of barrier property of stratum corneum by using model lipid systems. Biol. Pharm. Bull. 16 284—287 (1993). 

There are many immortalized human corneal epithelial cell models that gained high acceptance for various ocular studies (e.g., toxicity testing and corneal epithelial transport Table 12.1). 

Answer Aerosol delivery of the CFTR gene. Both viruses and liposome-DNA complexes are capable of successful CFTR gene transfer to the nasal and airway epithelia of patients with CF. In fact, gene transfer to the airways is one of the few areas where liposome-DNA complexes match the expression obtained using viral vectors without the viruses inflammatory side effects. Current trials are aimed at optimizing gene delivery with reduced toxicity to produce sustained correction of the epithelial transport defect. 

Murer, H. Kinne, R. (1980). The use of isolated membrane vesicles to study epithelial transport processes. J. Memb. Biol. 55, 81-95. 

Agerholm, C., et al. 1994. Epithelial transport and bioavailability of intranasally administered human growth hormone formulated with the absorption enhancers didecanoyl-L-alpha-phospha-tidylcholine and alpha-cyclodextrins in rabbits. J Pharm Sci 83 1706. 

Daum, N., Neumeyer, A., Wahl, B., Bur, M., and Lehr, C.-M. (2008) In vitro systems for studying epithelial transport of macromolecules, in Macromolecular drag delivery (Belting, M., ed.), Humana Press, pp. 151-164. 

In Vitro Systems for Studying Epithelial Transport of Macromolecules... 

Walter E, Kissel T, Reers M et al. (1995) Transepithelial transport properties of peptidomimetic thrombin inhibitors in monolayers of a human intestinal cell fine (CACO-2) and their correlation to in vivo data. Pharm Res 12(3) 360-365 Walter E, Kissel T (1995) Heterogeneity in the human intestinal cell line CACO-2 leads to differences in trans-epithelial transport. Eur J Pharm Sci 3 215-230 Ward JL, Tse CM (1999) Nucleoside transport in human colonic epithelial cell lines evidence for two Na-l—independent transport systems in T84 and CACO-2 cells. Biochim Bio-phys Acta 1419 15-22... 

Hartnup s disease. There is a defect in the epithelial transport of neutral amino acids (e.g., tryptophan) leading to poor absorption and excess excretion of these amino acids. Clinical signs resemble those of niacin deficiency (tryptophan is a precursor of niacin), namely the 3 D s Diarrhea, Dementia, Dermatitis. The condition responds to nicotinamide administration. Fan-coni s syndrome is a more generalized defect in molecular transport, involving a multitude of amino acids, glucose, calcium, phosphate, proteins, and other molecules. There may be decreased growth and rickets. 

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