L 733 060 hydrochloride

To determine if the effects of SP injection on ethanol drinking reflect endogenous SP activity, the ethanol-drinking rats from Experiment 1 which had cannulas in the aPVT or pPVT (n = 10/area), were tested one week after surgery by being injected with the NK1R antagonist, L-733,060 hydrochloride (0.5, 5.0 nmol; Tocris Bioscience, Minneapolis, MN, USA), counterbalanced against saline vehicle (0.3 μl; Hospira Inc.) in a within-subject Latin square design across three ethanol days. These antagonist doses were selected based on prior studies showing their central injection to antagonize the effects of SP and to alter pain processing (Chai et al., 2012 (link); Hamity et al., 2010 (link)). Then, two weeks after recovery from SP injections (see Experiment 1), they were injected with the specific NK1R antagonist RP 67580 (0.5, 5.0 nmol; Tocris) counterbalanced against dimethyl sulfoxide vehicle (0.3 μl; Sigma-Aldrich, St. Louis, MO, USA) in a within-subject Latin square design across three ethanol days. Following injections, intake of ethanol, food, and water was measured at 0.5 h, 1 h, 2 h, and 4 h.

To determine if the integrity of the SP system is necessary for OX to affect ethanol drinking, rats were trained to drink 20% ethanol and then cannulated in the aPVT or pPVT (N = 20). After recovery, they were injected with: 1) the NK1R antagonist L-733,060 hydrochloride (0.5 nmol; Tocris) followed 15 minutes later by OX-B (1 nmol; American Peptide); 2) saline (0.3 μl; Hospira Inc.) followed by OX-B (1 nmol); or 3) saline followed by saline, in a within-subject Latin square design across three ethanol days. Following injections, intake of ethanol, food, and water was measured at 0.5 h, 1 h, 2 h, and 4 h.