Effects of neurotensin on midbrain dopamine neuronal activity

The effects of acute intracerebroventricular administration of the tridecapeptide, neurotensin, and a pseudopeptide analog of neurotensin‐(8‐13) were compared to the effects of haloperidol and clozapine on the spontaneous activity of dopamine cells in both the ventral tegmental area (A10) and the substantia nigra compacta (A9). Unlike the typical antipsychotic haloperidol, which causes a non‐selective increase in both A9 and A10 cell activity, both neurotensin and a neurotensin analog, H‐Lys (CH2NH)Lys‐Pro‐Tyr‐lle‐Leu‐OH, in like manner to clozapine, at low doses selectively increase the number of spontaneously active A10 dopamine cells. These data provide the first in vivo evidence that acute administration of neurotensin can produce changes in spontaneous activity of midbrain dopamine cells similar to the atypical antipsychotic, clozapine.