Serial endoscopic observation of swine gastroesophageal ulceration induced by injection of a histamine-oil-beeswax mixture.

The gastroesophageal (GE) area of swine was endoscopically observed before and after injection of a histamine-oil-beeswax mixture (5 mg of histamine/kg of body weight). The swine were anesthetized with halothane, and a rigid endoscope was inserted through a gastric cannula placed in the proximal greater curvature of the stomach. Observation was simple and the procedure lasted less than 10 minutes, without adverse reactions. In 4 swine with normal GE areas, hemorrhage was found at postmedication hour (PMH) 3 and ulcerative changes were seen at PMH 9 to 12. A more rapid pathologic change of the GE area was found in 2 animals with hyper- or parakeratotic changes before medication. Abnormalities were found up to PMH 9 in the GE area of 2 animals in which the stomach cannula was opened to allow the escape of gastric juice.