T-2 Mycotoxin Intensifies Iodine Deficiency in Mice Fed Low Iodine Diet*

Mice were depleted of iodine and fed a 125I-labeled low iodine diet. After they developed isotopic equilibrium they were given T-2 mycotoxin, in doses 34% to. 14% of LD50/day for 4 to 12 days. In all cases T-2 toxin caused loss of thyroid iodine from which the animals recovered when the T-2 toxin was stopped. When iodine intake was adequate, the T-2 toxin had no statistically significant effect on the thyroid iodine content. Since T-2 toxin is known to block the initiation of some protein synthesis, it may block thyroglobulin synthesis, and, in stimulated thyroids, limited hydrolysis may continue. Therefore, when the thyroids were stimulated and thyroglobulin was depleted, a blockade of thyroglobulin synthesis may have caused further depletion of thyroidal iodine. (Endocrinology 118: 583–586, 1986)