Chronic lumbar intrathecal catheterization in the rat with reduced-length spinal compression.

The present paper describes an original technique, chronic lumbar catheterization of the subarachnoidal space in the rat. Introducing the catheter into the rachis directly at lumbar level reduces the length of the intrathecal catheter and, consequently, the extent of spinal cord compression. The validity of the technique is proved by the dose related effect obtained after morphine injections and the staining of the only spinal part of the central nervous system after blue-dye injections.