title: Neurotensin potentiates the potassium-induced release of endogenous dopamine from rat striatal slices.
abstract: The effects of neurotensin on the release of endogenous dopamine (DA) from rat striatal slices were investigated. DA was extracted by the aluminium adsorption method and assayed electrochemically by high-performance liquid chromatography. Neurotensin (2-100 microM) potentiated the potassium-induced release of striatal endogenous DA in a concentration-dependent manner. This neurotensin-induced release of DA was completely abolished in calcium-free medium containing EGTA 1 mM. The presence of tetrodotoxin 2 microM did not alter the effect of neurotensin 10 microM. On the other hand, neurotensin did not affect the uptake of [3H]DA into the striatal slices. In additional experiments, we confirmed that the KCl-induced release of DA in the nucleus accumbens was also potentiated b neurotensin. These results suggest that neurotensin has a direct effect on the central DA nerve terminals and releases DA in a Ca2+-dependent manner.
mesh_terms: D000818:Animals; D002118:Calcium / Q000502:physiology; D003342:Corpus Striatum / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009496:Neurotensin / Q000502:physiology*; D009638:Norepinephrine / Q000378:metabolism; D011188:Potassium / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors
chemical_list: D009496:Neurotensin; D013779:Tetrodotoxin; D011188:Potassium; D002118:Calcium; D004298:Dopamine; D009638:Norepinephrine