Parkinson's disease: depletion of substantia nigra neurotensin receptors.

Neurotensin receptor autoradiography reveals dense binding in normal human substantia nigra. In nigra from patients with Parkinson's disease, nigral receptor binding is only about one-third of control values. 'Saturation' analysis suggests that these changes result from receptor loss. These results support a neurotensin-dopamine interaction in human nigro-striatal circuits.