title: Identification of C-cells in normal and goitrous rat thyroid tissues using antiserum to rat thyrocalcitonin and the immunoperoxidase bridge technique.
abstract: Application of the immunoperoxidase bridge technique to the light microscopic localization of C-cells in rat thyroid tissue is described. Guinea pig antisera to rat thyrocalcitonin (TCT) were produced by the injection of highly purified rat TCT (100-300 MRC U/mg) emulsified in complete Freund's adjuvant. A 1:1000 dilution of the antiserum used in this study gave a strong positive reaction with rat C-cells, and 1 ml of undiluted antiserum provided sufficient material for staining approximately 5000 slides. The substitution of nonimmune guinea pig serum for the anti-rat TCT serum or the prior absorption of anti-rat TCT serum with increasing amounts of highly purified rat TCT both eliminated the staining of thyroid C-cells. Likewise, no staining was observed in tissue sections from rat parathyroid, ovary, pituitary gland, and skeletal muscle. Antiserum to synthetic human TCT also could be used to identify rat thyroid C-cells. The method revealed abundant C-cells in goiters from rats fed a low-iodine diet for more than 1 year. This finding was supported by electron microscopic evaluation of goitrous tissue and by the detection, by radioimmunoassay, of TCT in thyroid tissue and in peripheral blood from goitrous rats.
mesh_terms: D000818:Animals; D002116:Calcitonin / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006042:Goiter / Q000378:metabolism* / Q000473:pathology; D007106:Immune Sera; D007120:Immunochemistry; D008297:Male; D008722:Methods; D010544:Peroxidases; D051381:Rats; D013194:Staining and Labeling; D013961:Thyroid Gland / Q000166:cytology*
chemical_list: D007106:Immune Sera; D002116:Calcitonin; D010544:Peroxidases