IN VIVO imaging of mouse pancreas for experimental oncology and gastroenterology

Purpose. To obtain an image of the pancreas of a laboratory mouse by radiation imaging with different contrast agents. Materials and methods. Contrast-enhanced PET/CT was used to visualize the mouse pancreas. Gold nanoparticles were administered intravenously to C57/Bl6 female mice (22 g) as a contrast agent 48 h before PET/CT scanning. Amylum emulsion with “Ultravist-300” was administered through an oral gavage 1 day, 2 hours and 15 minutes before scanning. Official drug “Ultravist-300” was administered intravenously 10 minutes before scanning.¹⁸F-BPA was injected intravenously immediately before the study, and sequential CT and PET were performed using the MilLabs VECTOR6 trimodal imaging system for small laboratory animals. For image interpretation, reference images of Pirogov’s anatomical preparations of a laboratory mouse and atlases of CT and MRI imaging were used. Results. The pancreas of a laboratory mouse was visualized as a focus of increased¹⁸F-BPA uptake in the abdomen. Using the approach of sequential exclusion of syntopic organs from the analyzed area according to contrast-enhanced CT, it was proved that the observed focus corresponds to the pancreas, and its margins were determined. Conclusion. Using the PET/CT method with various contrast agents, a non-invasive in vivo image of the mouse pancreas was obtained. Its location in the abdominal cavity was precisely characterized, which will allow preclinical studies of new organotropic pharmaceuticals at a higher methodological level.

imaging, pancreas, mice, contrast media, gold nanoparticles

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