Establishment and investigation of a surgical model of hypothyroidism in Wistar rats.

BACKGROUND: The purpose of this study was to investigate the surgical model of hypothyroidism in rats and the feasibility and stability of the model. METHODS: Forty-eight adult male Wistar rats were randomly divided into 12 sham-operated rats (control group) and 36 operated rats (18 rats in the group with total thyroidectomy and 18 rats in the group with subtotal thyroidectomy). Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) serum concentrations were measured prior to surgery and on postoperative days 14, 28 and 90; blood calcium (Ca), blood phosphorus (P), and parathyroid hormone (PTH) concentrations were measured on postoperative day 10; and thyroglobulin (Tg) concentrations were measured on postoperative day 60. The postoperative behavioral status of the rats was comprehensively evaluated on the basis of behavioral indicators. RESULTS: There was no significant difference in preoperative TSH, FT4, or FT3 between the control and surgical groups (p > 0.05). On postoperative day 10, there were no significant differences in Ca, P, or PTH levels among the groups (p > 0.05). On postoperative days 14, 28 and 90, the TSH level was greater, whereas the FT4 and FT3 levels were lower in the surgical group (p < 0.05). On the 60th postoperative day, the Tg was significantly lower in the surgical group (p < 0.05). CONCLUSION: Surgical removal of the thyroid gland can be used to successfully establish a hypothyroid rat model that is stable and reliable and can provide a model basis for hypothyroidism-related research.