[P‐098]: Amyloid deposits imaging by passive staining in mouse models of Alzheimer's disease

A 1-42). Conclusions: Compact neuritic A plaques were abundant in the frontal cortex and absent in the cerebellum. 6-CN-BTA-1 bound to blood vessels and A 1-16/tau dual-labeled compact neuritic plaques in the frontal cortex; binding was not detected in the cerebellum. 6-CN-BTA-1 was more readily detected in A 1-40-immunoreactive (ir) plaques than in A 1-42-ir plaques. Diffuse non-neuritic A deposits were devoid of 6-CN-BTA-1 staining. Pretreatment of tissue sections with formic acid completely abolished 6-CN-BTA-1 staining. Our results demonstrate that 6-CN-BTA-1 labels preferentially compact neuritic plaques in AD brain, suggesting its affinity for binding to aggregated A . These data aid in interpreting the binding properties of the parent compound of 6-CN-BTA-1, PIB, which is currently under evaluation as an in vivo diagnostic marker of diseasespecific A plaque pathology progression in AD brains.