Tissue contents of endothelin vary according to thyroid hormone status in rat.

Endothelin-1 (ET-1) is a 21-residue peptide isolated from the conditioned medium of cultured porcine endothelial cells and is widely distributed throughout the body, with relatively high levels in the kidney and lung. In this study we examined the influence of thyroid hormone status on immunoreactive endothelin (ir-ET) levels in the plasma, lung, and kidney tissues of rats. Three weeks after surgical removal of the thyroid gland from male rats, the ir-ET levels in the lung and kidney were reduced by 39% and 42%, respectively. Similarly, ir-ET levels were decreased by 46% in the lung and 45% in the kidney of rats rendered hypothyroid by treatment with 0.1% (wt/wt) n-propylthiouracil (PTU) in the drinking water for 30 days