J. Kessler et al., Relationship between the histopathology of the endocrine-exocrine pancreasparenchyma and beta-cell function in the Chinese hamster CHIG Han subline, PANCREAS, 19(1), 1999, pp. 89-97
To investigate pancreatic histopathology in relation to islet function in t
ype 2 diabetes, pancreatic tissue was examined at disease onset and after d
eath in the genetically diabetic Chinese hamster CHIG/Han subline. The panc
reatic islets displayed vacuolation, intraislet fibrosis, variable Stages o
f degranulation, and beta-cell necrosis, but no insulitis. These lesions we
re associated with changes in immunostaining of major islet peptides, impai
red glucose-stimulated (10 mM) insulin secretion, reduced islet insulin con
tent, and the severity of hyperglycemia. The exocrine pancreas was characte
rized by peri- and intrapancreatic fat and mononuclear cell infiltration. B
iopsy of the pancreas had a marked effect on plasma glucose such that at 2
weeks after excision, in 9 and 18% of the severely hyperglycemic hamsters,
plasma glucose levels decreased to <7.2 and 15 mM, respectively, and 45% of
the mildly hyperglycemic hamsters became transiently normoglycemic (<7.2 m
M). The results showed that insulitis is not involved in beta-cell failure
of diabetic CHIG/Han hamsters. Vacuolation of islets was the most prominent
lesion associated with a functional islet abnormality and development of h
yperglycemia. Attenuation of hyperglycemia after biopsy suggests that the p
ancreas, in type 2 diabetes, maintains the ability to respond to impairment
with amelioration of the diabetic state.