[Prolactin level in thyroid diseases and its reaction to thyroliberin]

Prolactin content was determined before and after thyroliberin (TRH) injection in 15 healthy subjects and 136 patients. Basal levels of prolactin were increased in initial hypothyrosis, decreased in nodular euthyroid goitre, thyroid cancer and close to normal in thyrotoxicosis. TRH assay is more informative than the study of prolactin basal level. Prolactin hypophyseal content is decreased in diffuse toxic goitre, nodular euthyroid goitre, particularly, in cancer, being within normal in toxic adenoma and sharply increased in initial hypothyrosis. Hypothyrosis treatment produces a decrease in prolactin basal and stimulated levels down to normal. The treatment of diffuse toxic goitre leads to a slight rise only in the stimulated level of prolactin. Indices of TRH assays remained unchanged after surgical treatment of toxic adenoma.