title: Sequential morphological changes in pancreatic islets of spontaneously diabetic rats.
abstract: This study describes the sequential morphological changes in pancreatic islets from 1-, 6-, and 18-month-old male eSS rats, as compared to aged-matched control animals. Spontaneous diabetes mellitus was confirmed in 6- and 18-month-old eSS rats after an oral glucose tolerance test. Light microscopic immunocytochemical and morphometric techniques were used to study islet-cell populations. The pancreas was normal, and the morphometric methods did not reveal significant changes in islets from 1-month-old rats. However, 6-month-old eSS animals showed disruption of islet architecture and fibrosis in the stroma. The volume density (Vvi) of endocrine tissue and the Vvi and percentage of B cells were increased, whereas the Vvi of exocrine tissue and the Vvi and percentage of A cells were diminished. Eighteen-month-old eSS rats also exhibited conspicuous islet lesions. Nevertheless, the Vvi of endocrine tissue and the Vvi and percentage of B cells were diminished, while the Vvi of exocrine tissue and the Vvi and percentage of D cells were increased. Our results provide further quantitative evidence for the sequential morphological events occurring in the pancreatic islets of a useful animal model of diabetes mellitus.
authors.affiliation: CENEXA-Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Argentina.
authors.forename: C L
authors.initials: CL
authors.lastname: Gómez Dumm
authors.forename: M C
authors.initials: MC
authors.lastname: Semino
authors.forename: J J
authors.initials: JJ
authors.lastname: Gagliardino
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000473:pathology*; D005934:Glucagon / Q000032:analysis; D005951:Glucose Tolerance Test; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007328:Insulin / Q000032:analysis; D007515:Islets of Langerhans / Q000737:chemistry / Q000473:pathology*; D008297:Male; D010179:Pancreas / Q000473:pathology; D010191:Pancreatic Polypeptide / Q000032:analysis; D051381:Rats; D013004:Somatostatin / Q000032:analysis
chemical_list: D007328:Insulin; D013004:Somatostatin; D010191:Pancreatic Polypeptide; D005934:Glucagon