A NEW APPROACH FOR MULTIPLE SAMPLING OF CISTERNAL CEREBROSPINAL-FLUIDIN RODENTS WITH MINIMAL TRAUMA AND INFLAMMATION

A new approach was developed to minimize inevitable damage to nervous and meningeal tissue due to implantation of a sampling tube allowing m ultiple withdrawal of cerebrospinal fluid (CSF) from the cisterna magn a in adult rats. A tube was secured on the atlanto-occipital membrane. Thereafter, a hole was cut through the membrane, allowing flow of CSF from the cisterna magna to the tube. CSF could be sampled repeatedly for at least 1 week. There was no blood-brain barrier damage. The pres sure in the cisterna magna remained normal as did the estimated rate o f CSF formation. Very few blood cells contaminated the CSF. There was very little evidence of inflammation. The nervous tissue was undamaged as shown by exclusion of a dye-protein complex. The CSF concentration s of the cytosolic neuronal protein neuron-specific enolase (NSE), and of the astrocyte protein S-100 were very low. The pattern of amino ac ids remained within normal limits. Scanning electron microscopy reveal ed that clot and reactive changes were restricted to the vicinity of t he connecting hole. We conclude that our approach to positioning a tub e on the atlanto-occipital membrane and then connecting it to the cist erna magna reproducibly and reliably enables 'atraumatic' multiple sam pling of CSF.