Ferret islet amyloid polypeptide (IAPP): characterization of in vitro and in vivo amyloidogenicity.
ABSTRACT Diabetes in the domestic ferret (Mustela putorius furo) has previously been described and the purpose of this study was to evaluate if the ferret could serve as a model for the study of β-cell degeneration associated with formation of islet amyloid. The nucleotide and amino acid sequence of ferret islet amyloid polypeptide (IAPP) 1-37 was identified and the synthesized peptide was studied with regards to in vitro amyloidogenicity and potential cellular toxicity in a comparative approach to human, cat and the nonamyloidogenic rat IAPP. Ferret IAPP forms amyloid-like fibrils, but with a longer lag phase than human and cat IAPP and the aggregation process was shown to reduce cell viability of cultured β-cells, but with less potency than these two amyloidogenic counterparts. Immunohistochemistry of ferret pancreas confirmed IAPP expression in the islets of Langerhans, but no islet amyloid was found in a very limited sample size of one diabetic and five healthy ferrets. Islet amyloid has never been described in ferrets, and it is not possible to determine if it is due to lack of studies/material or to the fact that the ferret's life span is too short to present with such pathology.
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ABSTRACT: Diabetes mellitus was tentatively diagnosed in a black-footed ferret with polyuria, polydipsia, polyphagia, dehydration, and weight loss. Laboratory findings (marked hyperglycemia (724 mg/100 ml), glycosuria, and ketonuria) and the subsequent favorable response to insulin therapy confirmed the diagnosis. Although lesions were not observed in the pancreas, gross and histologic findings concomitant with diabetes mellitus included arteriosclerosis, with calcification of the aorta and other major vessels; mild necrotizing hepatitis; and mild proliferative glomerulonephritis. A perineal adenocarcinoma, with metastasis to an internal iliac lymph node, was an incidental finding. Special stains demonstrated adequate numbers of beta cell granules in the islets of Langerhans. Thus, the diabetes was apparently due to a lack of release of the synthesized insulin or to diminished effectiveness of the secreted insulin.Journal of the American Veterinary Medical Association 12/1977; 171(9):890-3. · 1.72 Impact Factor
- Upsala Journal of Medical Sciences 02/1972; 77(2):91-4. · 1.42 Impact Factor