Résumé : The effects of neurotensin in vitro were investigated on the binding characteristics of N-[3H]propylnorapomorphine ([3H]NPA) binding sites in crude membrane preparations from post mortem human caudate-putamen, obtained within 10 h after death from 3 patients without reported neurological or psychiatric diseases. Neurotensin (0.1-30 nM) was found to increase the Kd value of [3H]NPA binding sites with a maximal increase of about 50% (420±45 pM) at 3 nM of neurotensin, without significantly affecting the Bmax value (123±20 pmol/g protein). These results indicate the existence of an intramembrane regulation by neurotensin receptors of D2 receptors in the human caudate-putamen. © 1990.