Publications by authors named "N A Tobey"
Objectives: An early event in the pathogenesis of gastroesophageal reflux disease (GERD) is an acid-induced increase in junctional (paracellular) permeability in esophageal epithelium (EE). The molecular events that account for this change are unknown. E-cadherin is a junctional protein important in barrier function in EE.
View Article and Find Full Text PDFAim: The combination of smoking and drinking alcohol has a high association with diseases of squamous epithelium within the human oral cavity. Therefore, a study was done to assess the impact of these agents alone or in combination on the squamous epithelium using as model the buccal epithelium from rabbit oral cavity.
Methods: Buccal epithelium was mounted in Ussing chambers to monitor electrical parameters during exposure to ethanol (5-40%) or to Ringer extract of cigarette smoke (EOCS) from one to six cigarettes dissolved in 10 ml Ringer either alone or with combination.
Background And Aims: The structures that contribute to shunt resistance (Rs) in esophageal epithelium are incompletely understood, with 35-40% of Rs known to be calcium-dependent, reflecting the role of e-cadherin. Two calcium-independent candidates for the remaining approximately 60% of Rs have been identified: the glycoprotein matrix (GPM) within stratum corneum of esophageal epithelium, and the lateral cell membranes (LCMs) from neighboring cells.
Methods: To determine the contribution of GPM and LCMs to Rs, rabbit esophageal epithelium was mounted in Ussing chambers so that transepithelial resistance (R(T)), a marker of Rs, could be monitored during luminal exposure to either glycosidases for disruption of the GPM or to hypertonic urea for separation of the LCMs.