title: A simple and rapid method to collect the cerebrospinal fluid of rats and its application for the assessment of drug penetration into the central nervous system.
abstract: Many central nervous system (CNS) drug discovery programs require the successful collection of cerebrospinal fluid (CSF) for assessing CNS penetration and distribution of new chemical entities. The objective of the present investigation was to simplify the technique for collecting maximum CSF from cisterna magna of the rats. Rat was anesthetized with 5% halothane and positioned in a stereotaxic frame. The rat head was flexed downward at approximately 45 degrees , a depressible surface with the appearance of a rhomb between occipital protuberances and the spine of the atlas becomes visible. The 23 G needle was punctured into the cisterna magna for CSF collection without making any incision at this region. The blunt end of the needle was inserted into a 10 in. length of PE-50 tubing and other end of the tubing was connected to a collection syringe. The non-contaminated sample was drawn into the syringe by simple aspiration. This technique is simple and can be performed by one person. The technique has a greater than 95% success rate of CSF collection and it was free of red blood cell contamination. In addition, it yielded 100-120 microL of CSF per rat. This method is simple, effective, and easy to perform and has been successfully applied in preclinical screening of novel chemical entities in neuropharmacotherapy for CNS use. The present method is demonstrated by studying the CSF concentrations of carbamazepine and raclopride.
authors.affiliation: Pharmacokinetics and Drug Metabolism, Discovery Research, Suven Life Sciences Ltd., Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India. ramakrisha.nirogi@yahoo.co.in
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Nirogi
authors.forename: Vishwottam
authors.initials: V
authors.lastname: Kandikere
authors.forename: Koteshwara
authors.initials: K
authors.lastname: Mudigonda
authors.forename: Gopinadh
authors.initials: G
authors.lastname: Bhyrapuneni
authors.forename: Nageswararao
authors.initials: N
authors.lastname: Muddana
authors.forename: Ramanatha
authors.initials: R
authors.lastname: Saralaya
authors.forename: Vijay
authors.initials: V
authors.lastname: Benade
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000134:cerebrospinal fluid; D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects / Q000502:physiology; D002220:Carbamazepine / Q000008:administration & dosage / Q000134:cerebrospinal fluid; D002555:Cerebrospinal Fluid / Q000737:chemistry / Q000502:physiology*; D018492:Dopamine Antagonists / Q000008:administration & dosage / Q000134:cerebrospinal fluid; D008297:Male; D020891:Raclopride / Q000008:administration & dosage / Q000134:cerebrospinal fluid; D051381:Rats; D017208:Rats, Wistar / Q000134:cerebrospinal fluid*; D013048:Specimen Handling / Q000295:instrumentation / Q000379:methods*; D013997:Time Factors
chemical_list: D018712:Analgesics, Non-Narcotic; D018492:Dopamine Antagonists; D002220:Carbamazepine; D020891:Raclopride