Determination of acetylcholinesterase and pseudocholinesterase in gastrointestinal biopsy tissue.

An optimized micromethod for the determination of soluble acetylcholinesterase and pseudocholinesterase in gastrointestinal biopsy tissue is introduced. Enzyme activities were obtained from measurements of total activity and activity in the presence of an inhibitor of pseudocholinesterase. Optimal conditions of measurement were established for enzymes in serum or erythrocytes. In intestinal tissue, measurements were precise and reproducible. Interference by blood contained in the biopsy specimens were found to be neglegible. Also drugs used for premedication had no significant influence. Finally, results from normal stomach, duodenum and colon are presented.