BACKGROUND Claudins are transmembrane proteins expressed in tight junctions that prevent paracellular transport of extracellular fluid and a variety of other substances. However, the expression profile of Claudin-6 (Cldn6) in the developing lung has not been characterized. METHODS AND RESULTS Cldn6 expression was determined during important periods of lung organogenesis by microarray analysis...

Columnar epithelium-lined oesophagus (CELO) is an acquired disorder associated with a high incidence of cancer. CELO consists of three histological types of epithelium: gastric-fundic, junctional, and specialised columnar, the last resembling intestinal metaplasia of the stomach. In a previous study of CELO an incompletely differentiated variant of intestinal metaplasia secreting sulphomucins (...

The absorption of fluid by epithelial tissues is thought to be due to the existence of hypertonic regions within the epithelium. The magnitude of the required hypertonicity as well as its localization have been the subject of considerable experimental and theoretical effort. Model calculations demonstrated the need for knowledge of the water permeability of the membranes of epithelial cells for...

Urodeles begin gastrulation with much of their presumptive mesoderm in the superficial cell layer, all of which must move into the deep layers during development. We studied the morphogenesis of superficial mesoderm in the urodeles Ambystoma maculatum, Ambystoma mexicanum, and Taricha granulosa. In all three species, somitic, lateral, and ventral mesoderm move into the deep layer during gastrul...

The sense organ for hearing in birds, the basilar papilla, is capable of replacing lost or damaged hair cells and supporting cells through regeneration. Potential candidates for precursor-cell populations include cells within the auditory receptor epithelium and nonsensory cells inferior to the sensory epithelium. Ultrastructural characteristics of hyaline cells, border cells, and vacuole cells...

Wound healing in the inner ear sensory epithelia is performed by the apical domains of supporting cells (SCs). Junctional F-actin belts of SCs are thin during development but become exceptionally thick during maturation. The functional significance of the thick belts is not fully understood. We have studied the role of F-actin belts during wound healing in the developing and adult cochlea of mi...

The mechanisms of apparent streaming potentials elicited across Necturus gallbladder epithelium by addition or removal of sucrose from the apical bathing solution were studied by assessing the time courses of: (a) the change in transepithelial voltage (Vms). (b) the change in osmolality at the cell surface (estimated with a tetrabutylammonium [TBA+]-selective microelectrode, using TBA+ as a tra...

PURPOSE To investigate intercellular communication in the corneal epithelium, changes in the concentration of intracellular Ca(2+) ([Ca(2+)](i) ) induced by adenosine-5'-triphosphate (ATP) were analyzed. METHODS Rabbit corneal epithelia were loaded with Ca(2+) indicators and then stimulated by ATP (10 microM). [Ca(2+)](i) changes were monitored by means of conventional fluorescence and real-t...