A COMPARISON OF CULTURED RAT FRTL-5 AND PORCINE THYROID-CELLS FOR PREDICTING THE THYROID TOXICITY OF XENOBIOTICS

Two commonly used cell culture systems are currently available for testing the effects of xenobiotics on thyroid cell function and growth. These are the rat FRTL-5 thyroid cell line and the primary, cultured porcine thyrocyte. Both systems have inherent advantages and disadvantages. The FRTL-5 line has proved successful for testing growth stimulators, directly acting cytotoxic agents, and compounds directly affecting membrane transport processes (e.g. perchlorate anion: iodide transporter, ouabain: Na+K+-ATPase, amiloride: Na+-H+ antiporter). These cells can be produced in large quantities in monolayers and permit the necessary interlaboratory standardization procedures. However, these cells have a limited ability to iodinate thyroglobulin and synthesize thyroid hormones and thus, for testing for direct inhibitors of the peroxidases (e.g. sulphonylurea-like antithyroid agents), cultured porcine cells can be used. These cells can be 'manipulated' in culture to form 'pseudo-follicular' structures under the correct conditions. © 1990.