Imaging modalities are used to noninvasively study disease pathophysiology in the brain. Different modalities are used to assess gross anatomical structures, as well as changes in cellular and molecular structure and function. Advances in imaging techniques have allowed improved sensitivity and specificity for clinical and biomarker endpoints, consequently supporting early diagnosis and more efficient disease monitoring. MRI, PET, and SPECT are translational methodologies that serve as a bridge between preclinical studies and clinical endpoints.
Imaging has the potential to dramatically increase the efficiency of lead candidate selection by providing earlier and more highly predictive data, compared with traditional methods. Imaging is also well suited for facilitating translation between preclinical testing and clinical evaluation of drugs. Furthermore, imaging methods are more easily applied than traditional methods in the newer, more predictive models of human disease that are becoming increasingly prevalent.
Charles River’s preclinical neurological imaging capabilities include high-field MRI, PET/CT, and SPECT/CT scanners for radionuclide-based applications. These platforms are applicable for longitudinal studies with multiple imaging endpoints to study phenotype progression and treatment efficacy, as well as biodistribution or tissue activity changes. Currently, the imaging hardware for MRI studies on rodents include a 7.0T MRI scanner and 11.7T MRI scanner that are manned by 6 full time technicians and 2 scientists.
After a single administration, radiolabeled compounds can be used to follow pharmacokinetics and biodistribution profile for several days in the same animal with SPECT/CT. In addition to SPECT/CT, tissue gamma counter analysis can be added in all studies for a more complete biodistribution profile.
Radiolabeled molecules used for PK/biodistribution studies and autoradiography in mice and rats include commercial pre-labeled (3H,14C) and in-house labeled (125I, 123I, 99Tc, 111In) molecules, particles or cells.