The radioimmunological measurement of thyroglobulin secretion in vitro under the influence of some herbicides.

A radioimmunoassay (RIA) technique of human thyroglobulin (Tgl) was developed using 125I-Tgl and a rabbit anti-Tgl serum at the initial dilution of 1:100,000. The sensitivity of the technique was of 2.5 ng/ml. The RIA of Tgl was applied as a screening test for the in vitro secretory activity of human thyroid cells under the influence of two herbicides of the heterocyclic group (Amitrol and Atrazin). Three levels of concentration of Amitrol and Atrazin were administered to the tissue culture tubes containing in the first series of experiments perinodular tissue (Typ), and in the second one nodular tissue (TyN). The thyroid gland was surgically obtained from a patient with the diagnosis of polynodular goiter. Only the high levels (10 mg and 1.0 mg/tube, respectively) of herbicide concentration inhibited the secretion and release of Tgl, the nodular tissue being more resistant to the toxic. However, parallel studies including the dosage of the active hormones (T3, T4) are necessary in order to appreciate the value of Tgl determination as an indicator of hormogenesis in this type of experiments.