title: Functional and histochemical analysis on pancreatic islets of APA hamsters with SZ-induced hyperglycemia and hyperlipidemia.
abstract: To clarify how Syrian hamsters of the APA strain (APA hamsters) keep a diabetic condition for a long period, the functional and histochemical changes in the pancreatic islets of diabetic APA hamsters were examined. By glucose tolerance test, no glucose-induced insulin secretion was seen in the diabetic APA hamsters. By immunohistochemistry, it was revealed that at 24 hr after SZ-injection, the number of islets had decreased and that remnant islets had become markedly smaller. The islets had hardly any insulin-immunoreactive cells and consisted of cells stained by anti-glucagon and somatostatin antibodies. One, three and six months after SZ-injection, a small number of cells with vacuolative changes, which were positive for PAS staining, were observed in most islets and the vacuolated cells were stained mainly by anti-insulin antibody. In addition, a number of PCNA-positive cells were observed, especially in the periphery of the vacuolated cells, while TUNEL-positive cells were not detected. This data suggests that beta-cells proliferating as a result of the replication of the resident beta-cells in islets had fallen into degeneration and necrosis by a stress, such as the glycogen deposition in hyperglycemia and hyperlipidemia. Consequently, secretion of insulin was maintained at low levels, which allowed the hamsters to live without insulin therapy in the diabetic condition for over 6 months.
authors.affiliation: Department of Biomedical Science, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takatori
authors.forename: Etsuko
authors.initials: E
authors.lastname: Nishida
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Inenaga
authors.forename: Keiko
authors.initials: K
authors.lastname: Horiuchi
authors.forename: Seiji
authors.initials: S
authors.lastname: Kawamura
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Itagaki
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yoshikawa
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D006224:Cricetinae; D004195:Disease Models, Animal; D005934:Glucagon / Q000032:analysis; D005951:Glucose Tolerance Test; D006943:Hyperglycemia / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D006949:Hyperlipidemias / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007328:Insulin / Q000032:analysis; D007515:Islets of Langerhans / Q000737:chemistry* / Q000473:pathology*; D008297:Male; D008647:Mesocricetus; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D013004:Somatostatin / Q000032:analysis; D013311:Streptozocin / Q000032:analysis*; D014617:Vacuoles / Q000473:pathology
chemical_list: D001786:Blood Glucose; D007328:Insulin; D018809:Proliferating Cell Nuclear Antigen; D013004:Somatostatin; D013311:Streptozocin; D005934:Glucagon