Experimental model of acute appendicitis in the rabbit with determination of leucine amino peptidase (LAP) and acid phosphatase (acid-P) activities in portal blood samples.

The activities of leucine amino peptidase (LAP) and acid phosphatase (Acid-P), conceivable markers of acute appendicitis, were determined in the portal blood of rabbits with acute appendicitis. An experimental model of acute appendicitis was established using No.-O silk ties to block the base of the appendix. The clinical and histopathological picture of acute appendicitis was seen after 12 hr in all the rabbits in the model group (9/9) and in none of the control group. Catheterization of the superior mesenteric vein was performed in rabbits with acute appendicitis, and portal blood samples were taken at 0, 6, and 12 hr for assay of LAP and Acid-P activities. No statistically significant difference between the experimental group and the control group, in the activities of LAP and Acid-P, was found at any time interval. The experimental model of acute appendicitis in the rabbit which is described here is simple and carries a high rate of success. This is probably the first report of using continuous catheterization and repeated sampling of portal blood, for the measurement of enzyme activities, in an experimental model of acute appendicitis. It was concluded that serum LAP and Acid-P activities cannot be used as markers for acute appendicitis.