Cannula Implantation into the Cisterna Magna of Rodents

摘要: Cisterna magna cannulation (CMc) is a straightforward procedure that enables direct access to the cerebrospinal fluid (CSF) without operative damage skull or brain parenchyma. In anesthetized rodents, exposure of dura mater by blunt dissection neck muscles allows insertion cannula into cisterna (CM). The cannula, composed either fine beveled needle borosilicate capillary, attached via polyethylene (PE) tube syringe. Using syringe pump, molecules can then be injected at controlled rates directly CM, which continuous with subarachnoid space. From space, we trace CSF fluxes convective flow perivascular space around penetrating arterioles, where solute exchange interstitial (ISF) occurs. CMc performed for acute injections immediately following surgery, chronic implantation, later injection in awake, freely moving rodents. Quantitation tracer distribution parenchyma epifluorescence, 2-photon microscopy, and magnetic resonance imaging (MRI), depending on physico-chemical properties molecules. Thus, conjunction various techniques offers powerful tool assessment glymphatic system dynamics function. Furthermore, utilized as conduit fast, brain-wide delivery signaling metabolic substrates could not otherwise cross blood barrier (BBB).