Autoradiographic localization of [125I]-endothelin-1 binding sites in rat brain.

Autoradiograms of [125I]-endothelin (ET) binding in the rat brain demonstrated that the receptors for endothelin are localized mainly in the brainstem, basal ganglia, and cerebellum. Among the many other nuclei in these regions, there also appeared nuclei which are considered to play important roles in the central nervous regulation of the cardiovascular system: they include the nuclei of the anteroventral third ventricle area, the supraoptic nucleus, and the subfornical organ, for example. From these findings, we suggest that ET-1 or its analogous peptide(s) may act as a neuropeptide regulating central nervous functions, including cardiovascular functions.