Diabetes, Vol 30, Issue 12 1058-1061, Copyright © 1981 by American Diabetes Association
Lymphocytic thyroiditis and diabetes in the BB/W rat. A new model of autoimmune endocrinopathy
E Sternthal, AA Like, K Sarantis and LE Braverman
The Bio Breeding/Worcester (BB/W) rat develops spontaneous
insulin-dependent diabetes mellitus secondary to lymphocytic infiltration
and destruction of the pancreatic beta-cells. This destructive process in
the pancreas has been postulated to be based on a thymus-dependent
cell-mediated autoimmune process. In view of the well recognized
association in man of diabetes mellitus and another autoimmune
endocrinopathy, chronic thyroiditis (Hashimoto's thyroiditis), the present
studies were carried out to determine whether lymphocytic thyroiditis
occurred with increased frequency in the diabetic, insulin-treated BB/W
rat. The incidence of lymphocytic thyroiditis was strikingly increased in
8-10-mo-old diabetic rats (59%) as compared with their nondiabetic cohorts
(11%) (P less than 0.001). Relative thyroid weight was significantly
greater in diabetic as compared with nondiabetic rats (P less than 0.01)
and in diabetic rats with thyroiditis than in diabetic rats without
thyroiditis (P less than 0.025). Lymphocytic thyroiditis was not
accompanied by any consistent changes in serum T4, T3, and TSH
concentrations or in the serum TSH response to thyrotropin-releasing
hormone (TRH) suggesting that the thyroiditis was not of sufficient
severity or duration to induce primary thyroid gland failure. The BB/W rat
represents the first animal model of multiple autoimmune endocrinopathies
and provides a unique opportunity to study the pathogenesis of these
disorders.