A method for the continuous, long term superfusion of the cerebral cortex of unanaesthetized, unrestrained rats

The design, construction and testing of a cannula is described. It is made from nontoxic materials, has a very small dead volume and withstands normal intracranial pressure without leaking; it embodies facilities which prevent the tubing leads from twisting whilst allowing the animal to move freely, and which protect the tubing from attack by the animal. Other features include an electrode which allows stimulation of the area being superfused, and a heating block to bring the inflowing liquid to the animal's body temperature.