Thyrotropin induces changes in the morphology and the organization of microfilament structures in cultured thyroid cells

Thyrotropin (TSH) induces morphological changes in cultures of normal rat thyroid cell lines and in primary bovine thyroid cells. It also induces a specific reorganization of the microfilaments of the thyroid cells. Both effects are fully reversible and are mimicked by 8-bromo-cAMP. These results indicate that the trophic response of TSH involves changes in the organization of the actin-containing filaments, probably mediated through cAMP, followed by changes in cell shape.