Evaluation of experimental canine pancreatitis

Abstract

The usefulness of serum amylase determinations in evaluating and quantitating experimental canine pancreatitis is controversial. Serum amylase in the dog is normally 20 to 30 times higher than in man. On the other hand, some authors have stated that amylase is not normally excreted in dog urine. To evaluate the use of amylase determinations in experimentally produced canine pancreatitis, the pancreatic duct was ligated in five dogs, and serum and urine amylase measured daily for 9 days. The amylase methods used in this study had bypassed maltase activity, the cause of canine hyperamylasemia, but elevated serum levels were still found preoperatively. The techniques compared consisted of an automated Somogyi saccharogenic process expressed in maltose units percent, and an amyloclastic (Amylochrome) method; neither measured maltase. These methods correlated well; both serum and urine values had a P value at the 0.001 level. Postoperatively, serum amylase rose 30 to 40 times preoperative levels, and amylase appeared within 3 days after serum elevations in these animals. Possibilities for canine hyperamylasemia include a multienzyme complex producing erroneously high amylase values, increased amylase production, and lack of excretion or degradation of amylase. A fourth possibility, that of a macroamylase molecule in dog serum, was disproved by a rapid detection column method which revealed no abnormal amylase. The measurement of amylase clearance corrected by creatinine clearance was valueless because of decreased urine excretion. Whereas C Am/ C Cr percent in man is normally from 1 to 4%, it was found in this study that the canine preoperative average was 0.066%. These results emphasize again the marked differences in the behavior of the canine and human amylase systems, and for this reason, experimental studies of pancreatitis in the dog should be interpreted with caution.