The Effects of Anesthetic Agent and Carrier Gas on Blood Glucose and Tissue Uptake in Mice Undergoing Dynamic FDG-PET Imaging: Sevoflurane and Isoflurane Compared in Air and in Oxygen

Abstract

We sought to identify an anesthetic regime that, unlike isoflurane in air, would maintain glucose homeostasis in mice undergoing Positron emission tomography (PET) imaging with 2-deoxy-2-[18F]fluoro-D: -glucose (FDG). FDG uptake was also measured in normal and tumor tissues. Athymic and Balb/c nude mice were studied. Blood glucose levels were measured before and after 30 min of FDG PET imaging under isoflurane or sevoflurane carried in air or oxygen. FDG uptake was quantified as a percentage of the injected dose and using Patlak analysis yielding Ki values. Blood glucose levels were more stable under sevoflurane than under isoflurane, especially in the athymic nude mice. Under isoflurane, FDG uptake into myocardium was higher than under sevoflurane and was strongly correlated with the intrascan change in blood glucose. Sevoflurane should be preferred for physiologic imaging in mice, minimizing changes in glucose and, for FDG PET, reducing signal spillover from the myocardium.