Minerve

FDG-PET scanning was performed to detect orthotopic tumours. The 18 (link)F-FDG was produced and provided by Skåne University Hospital Cyclotron Unit. For PET-imaging, mice were intravenously injected with approximately 30 MBq of FDG and were imaged 1 h after administration using a preclinical PET/CT-scanner (Bioscan, USA). Mice were anaesthetised using 2–3% isofluorane and were placed in a temperature regulated animal chamber (Minerve, Bioscan, USA) with the temperature set to 37°C (Minerve multistation controller unit) during the scanning. During the acquisitions, respiration was monitored on PC (SA Instruments, Inc, USA) and anaesthesia levels were adjusted accordingly. CT scanning was performed using the X-ray exposure of 600 ms and 177 μA, and the zoom level set to medium zoom. The CT images were scanned with 180 projections/rotation, pitch 1.0 and a binning of 1:4. The CT reconstruction was performed utilizing a Butterworth filter algorithm. The PET acquisition was performed with the coincidence mode set 1-3. The PET data was acquired in list mode for 30 minutes, and reconstructed dynamically using the OSEM option and rebinning SSRB to 2D LOR with the ring difference set to 8. CT and PET images were evaluated and created using the InVivoScope software (InviCRO).

Experiments were conducted in accordance with the recommendations of the European commission (2010/63/EU) and the French national committee for the care and the use of laboratory animals. Experiments were approved by the regional committee on animal ethics (#2758). Rats were housed under constant environmental conditions with 12/12h light-dark cycles (ONCOModels/Centre Universitaire de Ressources Biologiques (CURB), approval n°A14118015) according to ARRIVE guidelines 36 (link) and γ-irradiated chow/water were provided ad libitum. Rats were maintained under isoflurane anesthesia (induction 5%, maintenance 2%, with 70% N₂O/30% O₂; Minerve system, Bioscan) throughout experimentations including imaging procedures. Body temperature was maintained at 37.5 °C by a rectal probe connected to an electric blanket, or using a feedback-controlled system (Minerve, Bioscan) integrated in the animal bed during the imaging sessions.