General Anesthesia Inhibits the Activity of the "Glymphatic System"

INTRODUCTION: According to the "glymphatic system" hypothesis, brain waste clearance is mediated by a continuous replacement of the interstitial milieu by a bulk flow of cerebrospinal fluid (CSF). Previous reports suggested that this cerebral CSF circulation is only active during general anesthesia or sleep, an effect mediated by the dilatation of the extracellular space. Given the controversies regarding the plausibility of this phenomenon and the limitations of currently available methods to image the glymphatic system, we developed original whole-brain in vivo imaging methods to investigate the effects of general anesthesia on the brain CSF circulation. METHODS: We used magnetic resonance imaging (MRI) and near-infrared fluorescence imaging (NIRF) after injection of a paramagnetic contrast agent or a fluorescent dye in the cisterna magna, in order to investigate the impact of general anesthesia (isoflurane, ketamine or ketamine/xylazine) on the intracranial CSF circulation in mice. RESULTS:In vivo imaging allowed us to image CSF flow in awake and anesthetized mice and confirmed the existence of a brain-wide CSF circulation. Contrary to what was initially thought, we demonstrated that the parenchymal CSF circulation is mainly active during wakefulness and significantly impaired during general anesthesia. This effect was especially significant when high doses of anesthetic agent were used (3% isoflurane). These results were consistent across the different anesthesia regimens and imaging modalities. Moreover, we failed to detect a significant change in the brain extracellular water volume using diffusion weighted imaging in awake and anesthetized mice. CONCLUSION: The parenchymal diffusion of small molecular weight compounds from the CSF is active during wakefulness. General anesthesia has a negative impact on the intracranial CSF circulation, especially when using a high dose of anesthetic agent.

Medienart:

E-Artikel

Erscheinungsjahr:

2018

Erschienen:

2018

Enthalten in:

Zur Gesamtaufnahme - volume:8

Enthalten in:

Theranostics - 8(2018), 3 vom: 15., Seite 710-722

Sprache:

Englisch

Beteiligte Personen:

Gakuba, Clement [VerfasserIn]
Gaberel, Thomas [VerfasserIn]
Goursaud, Suzanne [VerfasserIn]
Bourges, Jennifer [VerfasserIn]
Di Palma, Camille [VerfasserIn]
Quenault, Aurélien [VerfasserIn]
Martinez de Lizarrondo, Sara [VerfasserIn]
Vivien, Denis [VerfasserIn]
Gauberti, Maxime [VerfasserIn]

Links:

Volltext

Themen:

Alzheimer
Anesthesia
Anesthetics, Inhalation
Choroid plexus.
Contrast Media
Fluorescent Dyes
Glymphatic system
Journal Article
Magnetic resonance imaging
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 11.12.2018

Date Revised 11.12.2018

published: Electronic-eCollection

Citation Status MEDLINE

doi:

10.7150/thno.19154

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM280062168