摘要:
Non-invasive detection for amyloid-beta peptide (A beta) deposition has important significance for the early diagnosis and medical intervention for Alzheimer's disease (AD). In this study, we developed a series of imidazopyridine derivatives as potential imaging agents for single-photon emission computed tomography (SPECT). Two of them, compounds DRK092 and DRM106, showed higher affinity for synthetic human A beta 1-40 fibrils than did the well-known amyloid-imaging agent IMPY. A metabolite analysis revealed brain-permeable radioactive metabolites of I-125-labeled DRK092 and IMPY; no radioactive metabolites from I-125-labeled DRM106 ([I-125]DRM106) were detected. In addition, in vitro autoradiography clearly demonstrated specific binding of [I-125]DRM106 in the hippocampal region of AD enriched with A beta plaques. Thus, our results strongly suggested that compound DRM106 can be used as an imaging agent for SPECT to detect A beta deposition in AD brain. (C) 2014 Elsevier Ltd. All rights reserved.