Activated brown fat (aBAT) is known to affect the evaluation of 18F-FDG PET scans, especially in young patients. The aim of this study was to determine factors influencing the occurrence of aBAT, and to investigate the effectiveness of the two preventive measures, warming and beta-blocker (propranolol) administration. Five-hundred-twenty-eight 18F-FDG-PET scans of 241 EuroNet-PHL-C2 trial patients from 41 nuclear medicine departments in Germany and Czech Republic were screened for aBAT. The occurrence of aBAT was analyzed with patient characteristics (age, sex, body mass index, predisposition to aBAT), weather data at the day of 18F-FDG PET scanning as well as the preventive measures taken. Potentially important factors from univariate analyses were included into a logistic regression model. Warming as a preventive measure was used in 243 18F-FDG-PET scans, propranolol was administered in 36, warming and propranolol were combined in 84, and no preventive measures were taken in 165 scans. Whereas age, sex and body mass index had no clear impact, there was an individual predisposition to aBAT. Logistic regression model revealed that the frequency of aBAT mainly depends on the outside temperature (p = 0.005) and can be effectively reduced by warming (p = 0.004), the administration of unselective beta-blocker or the combination of both. Warming is a simple, cheap and non-invasive method to reduce the frequency of aBAT. However, the effect of warming decreases with increasing outside temperatures. Administration of propranolol seems to be equally effective and provides advantages whenever the positive effect of warming is compromised. The combination of both preventive measures could have an additive effect.

• MeSH
• beta blokátory farmakologie   MeSH
• fluorodeoxyglukosa F18 * farmakologie   MeSH
• hnědá tuková tkáň diagnostické zobrazování   MeSH
• lidé MeSH
• lymfom * MeSH
• pozitronová emisní tomografie metody   MeSH
• propranolol farmakologie   MeSH
• radiofarmaka farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky MeSH
• Názvy látek
• beta blokátory MeSH
• fluorodeoxyglukosa F18 * MeSH
• propranolol MeSH
• radiofarmaka MeSH

We performed micro-CT imaging of the vascular blood supply in the interscapular area of the brown adipose tissue in three mice with the use of intravascular contrast agent Aurovist™. Resulting 3D data rendering was then adapted into 2D resolution with visualization using false color system and grayscale images. These were then studied for the automatic quantification of the blood vessel density within this area. We found the highest most occurring density within arterioles or venules representing smaller blood vessels whereas with the increase of the vessel diameters a lower percentage rate of their presence was observed in the sample. Our study shows that micro-CT scanning in combination with Aurovist™ contrast is suitable for anatomical studies of interscapular area of brown adipose tissue blood vessel supply.

• MeSH
• cévy anatomie a histologie   diagnostické zobrazování   MeSH
• hnědá tuková tkáň anatomie a histologie   krevní zásobení   diagnostické zobrazování   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• rentgenová mikrotomografie MeSH
• venuly anatomie a histologie   diagnostické zobrazování   MeSH
• zobrazování trojrozměrné MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Brown adipose tissue (BAT) physiology and imaging have recently attracted considerable attention. BAT is characterized both by enhanced perfusion and increased mitochondrial activity. (99m)Tc-sestamibi is a lipophilic cationic tracer that concentrates in mitochondria. Data on the accumulation of (99m)Tc-sestamibi in BAT are currently lacking. This study investigates the in vivo (99m)Tc-sestamibi uptake in rat BAT. (99m)Tc-sestamibi was administered in male Wistar rats of various age and body size. (99m)Tc-sestamibi uptake was measured in vitro in BAT and white fat (WF) together with cytochrome c oxidase activity. Both (99m)Tc-sestamibi uptake and cytochrome c oxidase activity were higher in BAT than in WF (P<0.05). (99m)Tc-Sestamibi uptake in both BAT and WF was negatively related to body weight (r = -0.96 and -0.89, respectively) as was the BAT/WF uptake ratio (r = -0.85). These data show a higher (99m)Tc-sestamibi uptake in BAT compared to WF, in agreement with the high mitochondrial content and respiratory activity of the former. The strong negative correlation between (99m)Tc-sestamibi uptake in BAT and body weight (negative allometry), is in accordance to increased needs of thermogenesis in smaller animals. Implications of increased (99m)Tc-sestamibi uptake in BAT in radionuclide imaging are also discussed.

• MeSH
• bílá tuková tkáň metabolismus   MeSH
• hnědá tuková tkáň diagnostické zobrazování   metabolismus   fyziologie   MeSH
• krysa rodu Rattus MeSH
• mitochondrie diagnostické zobrazování   metabolismus   fyziologie   MeSH
• potkani Wistar MeSH
• radiofarmaka metabolismus   MeSH
• radioisotopová scintigrafie MeSH
• respirační komplex IV metabolismus   MeSH
• stárnutí metabolismus   MeSH
• technecium 99mTc sestamibi metabolismus   MeSH
• tělesná hmotnost MeSH
• termogeneze * MeSH
• věkové faktory MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• radiofarmaka MeSH
• respirační komplex IV MeSH
• technecium 99mTc sestamibi MeSH