Peptide p5 specifically binds to AA amyloid when injected iv into AA mice as evidenced in micro-autoradiographs. Black deposits indicate the presence of 125I-p5 at sites confirmed to contain amyloid by Congo red staining of consecutive tissue sections. (A) lymph node, (B) adrenal gland, (C) renal cortex, (D) liver, (E) spleen, (F) gastric wall, (G) small intestine, (H) renal papilla, and (I) pancreas.