Metabolic rate of oxygen in the brown adipose tissue (BAT) using [15O]O2-PET
Model for BAT [15O]O2-PET
Muzik et al. (2012, 2013) have measured oxygen consumption and oxygen extraction rate (OER, or oxygen extraction fraction, OEF) in BAT applying the dynamic method that has been developed and validated for the brain (Mintun et al., 1984; Huang et al., 1986; Hattori et al., 2004). This approach involves three PET studies: a single-inhalation [15O]O2, an intravenous bolus injection of [15O]H2O, and a single-inhalation of [15O]CO, and enables estimation of perfusion, vascular volume fraction in tissue (VB), metabolic rate of oxygen (MRO2), and OER. Arterial input function is required, but in BAT studies it can be measured from the PET image (Muzik et al., 2013). However, at least one arterial blood sample is required in [15O]O2 study to determine the amount of recirculating [15O]H2O (Mintun et al., 1984).
Image analysis
PET/CT scan with [18F]FDG is required to determine whether subject has marked brown adipose tissue (BAT) deposits or not, and to define regions-of-interest (ROIs) for BAT and white adipose tissue (WAT) in the cervical and supraclavicular areas (Muzik et al., 2012 and 2013). CT density and [18F]FDG SUV50-60min were used to draw the ROIs, which were then transferred to 15O images, and regional time-activity curves (TACs) were calculated (Muzik et al., 2012 and 2013).
See also:
Literature
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Updated at: 2013-06-13
Written by: Vesa Oikonen