Thyrotoxic Pericarditis in a Mouse Model of Graves' Disease

Objectives: To investigate the cardiac pathological changes of hyperthyroid heart disease in mice. Methods: A transient model for human Graves’ disease was successfully established in mice using three immunizations with recombinant adenovirus expressing the extracellular A subunit of the human thyrotropin receptor (Ad-TSHR). We induced the hyperthyroid heart mouse model by prolonging the regular injections of Graves’ disease mouse model to nine months. Heart tissues were weighed and stained with hematoxylin-eosin (HE) and MASSON Trichrome staining to check and define the pathological changes. Results: We observed that mice in the Graves’ disease hyperthyroid heart group (GH) showed enhanced cardiac hypertrophy and fibrosis. The HW/BW (ratio of heart weight to body weight) of GH group (5.528±0.4014, n=6) was significantly higher than control group (4.343±0.03913, n=6) (P<0.05). In GH group, 2 of 6 hearts showed typical cor villosum (Image 1). The MASSON Trichrome staining exhibited aggravated cardiac fibrosis on the surface of the heart in GH group. Conclusions: Pericarditis as a complication of thyrotoxicosis has been reported several times in clinical work. This is the first reported case of pericarditis in the mouse model of Graves’ disease, suggesting a possible link between pericarditis and thyrotoxicosis.