TY - JOUR
T1 - Naloxone Facilitates Extinction but Does Not Affect Acquisition or Expression of Ethanol-Induced Conditioned Place Preference
AU - Cunningham, Christopher L.
AU - Dickinson, Shelly D.
AU - Okorn, Dobrina M.
PY - 1995/11
Y1 - 1995/11
N2 - Mice (DBA/2J) received a Pavlovian procedure in which a distinctive floor stimulus was paired 4 times with ethanol (2 g/kg). A different floor stimulus was paired with saline. Naloxone (0.0, 1.5, or 10.0 mg/kg, intraperitoneal) given before each ethanol trial did not interfere with acquisition of conditioned preference, although naloxone alone produced conditioned aversion. When naloxone (0.0, 0.15, 1.5, 3.0, or 10.0 mg/kg) was given for the first time during testing, mice showed conditioned preference during the first 10 min. However, preference subsequently decreased dose-dependently over time. Control studies eliminated alternative interpretations based on pharmacokinetics or presence of an aversive state. The overall pattern of results suggests that naloxone facilitated extinction of conditioned place preference and supports the hypothesis that ethanol-induced conditioned reinforcement is mediated by the endogenous opioid system.
AB - Mice (DBA/2J) received a Pavlovian procedure in which a distinctive floor stimulus was paired 4 times with ethanol (2 g/kg). A different floor stimulus was paired with saline. Naloxone (0.0, 1.5, or 10.0 mg/kg, intraperitoneal) given before each ethanol trial did not interfere with acquisition of conditioned preference, although naloxone alone produced conditioned aversion. When naloxone (0.0, 0.15, 1.5, 3.0, or 10.0 mg/kg) was given for the first time during testing, mice showed conditioned preference during the first 10 min. However, preference subsequently decreased dose-dependently over time. Control studies eliminated alternative interpretations based on pharmacokinetics or presence of an aversive state. The overall pattern of results suggests that naloxone facilitated extinction of conditioned place preference and supports the hypothesis that ethanol-induced conditioned reinforcement is mediated by the endogenous opioid system.
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U2 - 10.1037/1064-1297.3.4.330
DO - 10.1037/1064-1297.3.4.330
M3 - Article
AN - SCOPUS:0028879203
SN - 1064-1297
VL - 3
SP - 330
EP - 343
JO - Experimental and Clinical Psychopharmacology
JF - Experimental and Clinical Psychopharmacology
IS - 4
ER -