ABSTRACT
Amyloid fibrils were extracted from 4 µm-thick formalin-fixed, paraffin-embedded kidney sections using 6 M/L guanidine HCl. For sequencing analyses, the amyloid protein extract was dissolved in 0.1% SDS buffer containing 0.1 M/L dithiothreitol and 8 M/L urea and electrophoresed on 10% SDS/PAGE gels. Passage of the reduced and alkylated amyloid extract through a reverse-phase HPLC column yielded 2 major peaks. For tandem mass spectrometric identification of peptides, samples were separated by reverse phase HPLC and the effluent directed into an ion-trap mass spectrometer. The chapter describes the clinical features and postmortem findings in a 16-year-old gelding that succumbed to extensive cardiac amyloidosis, but also had similar deposits in the gastrointestinal tract, spleen, kidney, and liver.
