Spiperone

All other screening compounds, except m-CPP (Sigma-Aldrich) were from Tocris Bioscience: Sumanirole (D₂ agonist), Spiperone (5-HT_2A serotonin and selective D₂-like dopamine receptor antagonist), Lisuride (D_2∼4 agonist), Pramipexole (D_2∼4 agonist), BW723C86 (5-HT_2B receptor agonist), m-CPP (Pan-serotonin agonist), Dihydrexidine (full agonist at the dopamine D1 and D5 receptors), Cabergoline (D_2∼4 agonist, possible prolactin inhibitor), DL-TBOA (EAAT blocker)

LENART01 was synthesized as described elsewhere [8 (link)]. In the case of receptor binding assays, the GTP analog GTPγS and GDP were purchased from Sigma-Aldrich (Budapest, Hungary). The highly selective MOR agonist Tyr-D-Ala-Gly-(NMe)Phe-Gly-ol (DAMGO) and the selective MOR agonist dermorphin were both obtained from Bachem Holding AG (Bubendorf, Switzerland). The non-selective opioid receptor antagonist naloxone was kindly provided by the company Endo Laboratories DuPont de Nemours (Wilmington, DE, USA). SCH-23390, a selective dopamine receptor DRD1 antagonist, and the selective DRD2 antagonist, spiperone, were obtained from Tocris Bioscience (Bristol, UK). The radiolabeled [³⁵S]GTPγS with specific 1000 Ci/mmol activity was purchased from Hartmann Analytic (Braunschweig, Germany). Similarly, [³H]DAMGO (38.8 Ci/mmol) was radiolabeled in the Isotope Laboratory of BRC (Szeged, Hungary), while [³H]SCH−23390 (83.2 Ci/mmol) and [³H]spiperone (80.2 Ci/mmol) were obtained commercially from PerkinElmer (Boston, MA, USA).