Multiple-Radionuclide Autoradiography in Evaluation of Cerebral Function

We have developed the mathematical model and experimental technique for quantitative simultaneous multiple-radionuclide autoradiography. The technique is an extension of previously described dual-tracer methods and offers the advantage of a general approach in which any two or more radionuclides with different half-lives can be used to measure multiple parameters of cerebral function. The model allows the selection of nuclide doses and exposure times to balance cross-contamination of the multiple images with nuclide requirements. The technique was validated with homogeneous tissue sections containing combinations of 123I, 124I, 131I, 18F, 99mTc, 68Ga, and 14C, and then used in qualitative and quantitative investigations of interrelationships of local cerebral blood flow, glucose metabolism, and protein synthesis in normal and several pathological conditions in rats.