The technique for transposition of infrarenal segments from the abdominal aorta and the caval vein, respectively, was described and morfological changes characterized. The vessel walls in the transposed caval segments became "arterialized" 1 month after the operation due to increased connective tissue in the media. Fibrin depositions were found on the intimal layer. The transposed aortic segments had no morfological changes. The described model was found to be a simple and valuable method for vascular research in small animals.