Abstract
A technique for long-term infusion into the inferior mesenteric artery was developed which allows simple and reliable regional infusion into the colorectal segment of unrestrained rats. The cannulation system consists of an injection port 'In Stoppers' as a flow swivel, connected to an injection needle, which is inserted into a polyethylene tube protected by a steel spiral. During infusion the animals are free to move in the cage with access to food and water ad libitum. The method is suitable for regional chemotherapy as well as for studies of colorectal tumours in rats. In this study 73% of the cannulae remained functional for continuous infusion over a 15 day period.