Human Recombinant Interleukin-1 beta Decreases Plasma Thyroid Hormone and TSH Levels in the Rat

While physiopathological studies with human recombinant interleukin 1 (hrlL-1) have focused mainly on its role as a mediator between macrophages and monocytes and the immune system, effects on endorine functions have also been seen. The first reports concerned the cytotoxic effects of hrIL-1 on islet beta cell function [1], Shortly there-after studies in thyroid cell cultures were reported [2]. These studies both found that very low doses of hrIL-1 (10-14–10-16 M) stimulated the secretion of insulin and potentiate the effect of TSH on the secretion of thyroid hormones. Many other metabolic effects have now also been reported. hrIL-1 affects the regulation of glucocorticoids as it increases ACTH in stress, yet a direct effect on adrenal function remains to be established [3]. Fluid balance is also affected as hrIL-1 decreases renal sodium absorption [4].