A non-invasive method of cerebrospinal fluid collection from rats for assessing the cerebrospinal fluid drug content

The drug discovery and pharmacokinetic studies of drugs of the central nervous system depend on the successful collection of cerebrospinal fluid from lab animal models. Many a time, the treatment regime and management of diseases depends on the penetration and distribution of medicaments across the blood-brain barrier and for which a non-contaminated cerebrospinal fluid sample is essential. The present study was to simplify the cerebrospinal fluid collection from cisterna magna of rat, maximizing the quantity and minimizing the contamination. The rat is anaesthetized with Xylazine Ketamine combination intravenously and was kept on an inverted polypropylene tray with its head down at 45° angle. A depressible surface which look like a rhomb between occipital protuberances and the spine of the atlas becomes noticeable. A butterfly needle attached to a syringe was introduced into the cisterna magna, and cerebrospinal fluid is aspirated. The method is non-invasive and doesn’t require any sophisticated equipment and lessens the chance of contamination of the sample with blood. The technique is also less time consuming and easy to perform.