MORPHOLOGIC ALTERATIONS IN EARLY ACID-INDUCED EPITHELIAL INJURY OF THE RABBIT ESOPHAGUS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 45  (2) , 198-208
Abstract
The pathogenesis of reflux esophagitis was studied. An acute experimental model in the rabbit for studying the early lesion was developed. Acid was perfused in vivo into the lower esophagus while potential difference was intermittently monitored. At varying degrees of potential difference decline, indicating epithelial injury, the esophageal stratified squamous epithelial tissue was removed for morphological studies and in vitro electrophysiologic and transport studies. At 50% reduction in potential difference, there was dilation of intercellular spaces, which when correlated with physiologic results of increased permeability indicates increased intercellular water. At 100% reduction in potential difference, cells in the midepithelium were swollen and ruptured, forming vesicular spaces, midepithelial cleavages and later early ulceration. Results of functional studies at this stage showed inhibition of Na transport. The midepithelial site of disruption corresponds to the site of active Na pumping out of cells in other stratified squamous epithelia. Since Na is transported by esophageal epithelium and this function was inhibited by acid, this early morphologic lesion may be the result of damage to the Na-transporting mechanisms of the epithelium.