Autoradiographic visualization of the binding sites for [125I]endothelin in rat and human brain.

Putative receptors for endothelin were localised autoradiographically in frozen sections of rat and human brain using [125I]endothelin as a ligand. In the rat brain the highest densities were in the granular layer of the cerebellum, choroid plexus, hippocampus, and habenular nucleus. Similar brain high densities were found in the human cerebellum and hippocampus. The non-vascular pattern of distribution suggests that endothelin may have a function as a modulator of neuronal function in addition to its possible involvement in the regulation of vascular tone.