Morphology of thyroid follicular cells of methimazole-treated rats.
Thyroids of rats treated with methimazole (MMI) were analysed histologically, immunohistochemically and electron microscopically. Thyroids of MMI-treated rats displayed greater hypertrophy and were heavier than those of control rats. Thyroids of MMI-treated rats were composed of variant or small follicles and contained more columnar cells than those of control rats. Strong staining of thyroid granules by azocarmine G was evident in the apical regions of follicular cells from MMI-treated rats. Anti-thyroglobulin positivity was detected in the apical regions of follicular epithelial cells, especially those of MMI-treated rats. After application of a post-embedding method to detect thyroglobulin, colloidal gold particles were often observed in apical vesicles of MMI-treated rats. Our study suggests that apical vesicles may serve as markers of hyperthyroidism. When the functional state of the thyroid gland is known from histological analysis, use of the Azan stain could provide useful additional information.
Tsujio
M
M
Department of Veterinary anatomy, School of Veterinary Medicine and Animal Sciences, Kitasato University, Towada-shi, Aomori, Japan 034-8628.
Watahiki
Y
Y
Yoshioka
K
K
Mutoh
K
K
D000818:Animals; D013956:Antithyroid Agents / Q000494:pharmacology*; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D008713:Methimazole / Q000494:pharmacology*; D008854:Microscopy, Electron / Q000662:veterinary; D051381:Rats; D017208:Rats, Wistar; D013961:Thyroid Gland / Q000166:cytology* / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure
D013956:Antithyroid Agents; D008713:Methimazole