Cerebrospinal fluid collection in laboratory mice: Literature review and modified cisternal puncture method

BACKGROUND: The composition of cerebrospinal fluid (CSF) is an invaluable parameter in better understanding of cellular and molecular processes within the mammalian brain. However, the collection of significant volumes of clean CSF can be technically challenging in studies with laboratory mice. Over the past five decades, several approaches have been developed to maximize the quantity and quality of CSF samples, either from live or euthanized animals. Due to the small amounts collected, samples from single mice were often pooled or diluted to meet volume requirements of automated counters and multiple assays. NEW METHOD: This paper reviews previous work on CSF collection in mice, thus providing methodological background for the current post-mortem procedure. This modified cisternal puncture method involves the use of a peristaltic pump for consistent and slow intracardiac perfusion, as well as a loupe headset with a custom-made glass pipette for piercing a single hole in the atlanto-occipital membrane during repeated CSF draws. Sample cleanness is verified by comparing the colour of the glass pipette and the bottom of centrifuged PCR vial against a white background. RESULTS: With three trained experimenters, the entire procedure (including anesthesia) takes ∼11-13 min and often results in the collection of up to 40 μl of clean CSF from males of different murine strains. Properly staggered collections allow processing of relatively large cohorts of mice per day. CONCLUSIONS: This modification of previously employed methods can be used in studies that require tightly-timed collections of larger volumes of undiluted, tissue-free CSF and/or individual data records.