Figure 1.
Gadolinium-enhanced magnetic resonance imaging of the brain after intracisternal injection of DOTA-Gd followed by wakefulness or isoflurane general anesthesia. (A) Schematic representation of the experimental design of the Magnetic Resonance Imaging (MRI) experiments. (B) Representative high-resolution T1-weighted images 60 min after intracisternal injection of DOTA-Gd (1 µL) in awake (top) and anesthetized mice (isoflurane 2-2.5%, bottom). Whereas DOTA-Gd (materialized by an increased signal intensity) was present mainly in the cerebrospinal fluid (CSF) of anesthetized mice, it was found in the whole brain of awake animals. (C) Representative high-resolution T1-weighted images before and 60 min after intracisternal injection of DOTA-Gd (1 µL) in awake (top) and anesthetized mice (bottom). (D) Corresponding quantification of the signal intensity in four different regions of interest (Cerebellum, Olfactory Bulbs (OB), Motor Cortex and Hippocampus). The signal intensity ratio is significantly more important in the awake group, supporting an increased activity of the CSF circulation during wakefulness when compared to anesthetized animals (n=5 mice per group). Scale bar: 2 mm.