Abstract The changes in morphology and proliferation kinetics produced by colchicine in the intestinal mucosa are known. Contrarily, the functional changes have yet not been investigated systematically. The aim of this study is to investigate the effects of colchicine treatment on rat intestinal disaccharidase activities. Material and methods: For the experiments male SPF-Wistar rats, body weight 180-200 g-(supplied by Mus-Rattus AG, 8011 Brunnthal, FRG) were used. The animals were kept under constant conditions (6 rats per cage) and fed Altromin® (Altromin GmbH, Lage/Lippe), tap water ad libitum. Per day 6 animals of each test group were scarificed by cervical dislocation at defined time. About 3 cm of the intestine were removed 8-10 cm distally of the pylorus and cut longitudinally. After cautious cleaning the mucosa was detached using a scalpel. The thus obtained specimens of the mucosa were frozen at –20 °C in an air-tight humidity chamber and preserved there until further handling. For histological examination the correspondent parts of the intestine were fixed in 10 % formol. From each specimen 4 different stainings were made (haematoxylin-eosin, Giemsa, PAS and Feulgen stain). Per test series 60–66 rats were used. The following doses of colchicine were applied: 1 × 1.0 mg/kg body weight, 1 × 0.5 mg/kg body weight, 5 × 0.1 mg/kg body weight within 24 hours. The single doses were dissolved in about 0.5 physiological saline and applied intraperitoneally. In each 6 rats per group the activities of the following diasccharidases were measured at 24 hours intervals from the 1st to 10th or 14th day: sucrase, maltase, lactase, and cellobiase. The enzyme activities were determined after the two-step method developed by Dahlqvist (5, 6) which can be used as micromethod. The ascertained enzyme activities were always related to the protein content. Protein determination was done after the method of Folin-Ciocalteu as modified by Lowry et al. (14). The enzyme activities were expressed in international units per g protein (U/g protein). The results obtained were statistically ascertained by the non-parametric test after Kruskal-Wallis, variance analysis with linear contrasts after Scheffe as well as by double variance analyses (26).