Endocrinology, Vol 116, 1379-1382, Copyright © 1985 by Endocrine Society

ARTICLES

Bovine thyrotropin has a specific bioactivity 5- to 10-fold that of previous estimates for highly purified hormone

B Rapoport and P Seto

Bovine TSH (bTSH) was subjected to reverse phase HPLC using a Synchropak RP-P C18 column. Elution was with a linear gradient of 0-50% 1-propranol in 0.1% trifluoroacetic acid. Individual fractions were assayed for TSH bioactivity by the cultured thyroid cell cAMP response assay. Optimum separation of biologically active TSH was obtained at a mobile phase pH of 5. Under these conditions, bTSH purified by conventional chromatographic techniques to 25 U/mg protein was purified further to approximately 200 U/mg protein. These data indicate that bioactivity is only present in a relatively small fraction of the molecules in a highly-purified TSH preparation. The implications of these findings are discussed.

This article has been cited by other articles:

				M. Tonacchera, P. Agretti, A. Pinchera, V. Rosellini, A. Perri, P. Collecchi, P. Vitti, and L. Chiovato Congenital Hypothyroidism with Impaired Thyroid Response to Thyrotropin (TSH) and Absent Circulating Thyroglobulin: Evidence for a New Inactivating Mutation of the TSH Receptor Gene J. Clin. Endocrinol. Metab., March 1, 2000; 85(3): 1001 - 1008. [Abstract] [Full Text]

				M. Tonacchera, L. Chiovato, A. Pinchera, P. Agretti, E. Fiore, F. Cetani, R. Rocchi, P. Viacava, P. Miccoli, and P. Vitti Hyperfunctioning Thyroid Nodules in Toxic Multinodular Goiter Share Activating Thyrotropin Receptor Mutations with Solitary Toxic Adenoma J. Clin. Endocrinol. Metab., February 1, 1998; 83(2): 492 - 498. [Abstract] [Full Text]