Differential effects of bupropion on acquisition and performance of an active avoidance task in male mice

Bupropion, Alone and in Combination with Naltrexone, Blunts Binge-Like Ethanol Drinking and Intake Following Chronic Intermittent Access to Ethanol in Male C57BL/6J Mice

BACKGROUND

Regular binge drinking is associated with numerous adverse consequences, yet the U.S. Food and Drug Administration (FDA) has approved only 4 medications for the treatment of alcohol use disorders, and none have been specifically targeted for treating binge drinking. Here, we assessed the effectiveness of the dopamine/norepinephrine re-uptake inhibitor, bupropion (BUP), alone and in combination with naltrexone (NAL), to reduce binge-like and chronic ethanol (EtOH) intake in mice. While BUP is an FDA-approved drug that is currently used to treat depression and nicotine dependence, there has been only limited investigation to assess the ability of BUP to reduce EtOH intake.

METHODS

Male C57BL/6J mice were tested with 20% (v/v) EtOH using "drinking in the dark" (DID) procedures to model binge-like EtOH intake and following intermittent access to EtOH (IAE). In Experiment 1, mice were given intraperitoneal (i.p.) injection of 0, 20, or 40 mg/kg BUP 30 minutes before DID testing; in Experiment 2, mice were given i.p. injection of vehicle, BUP (20 mg/kg), NAL (3 mg/kg), or BUP + NAL (20 and 3 mg/kg, respectively) 30 minutes before DID testing; and in Experiment 3, mice were given i.p. injection of 0, 20, 40, or 60 mg/kg BUP 30 minutes before EtOH access after mice had 16 weeks of IAE.

RESULTS

BUP dose dependently blunted EtOH intake with DID procedures and after 16 weeks of IAE. Administration of subthreshold doses of BUP + NAL also reduced binge-like EtOH intake. Finally, BUP failed to reduce consumption of a 3% (w/v) sucrose solution.

CONCLUSIONS

BUP, alone and in combination with NAL, may represent a novel approach to treating binge EtOH intake. We are currently assessing the efficacy of BUP to curb binge drinking in a phase II clinical trial experiment.

The effect of paroxetine, venlafaxine and bupropion administration alone and combined on spatial and aversive memory performance in rats

BACKGROUND

The use of antidepressants in combination is common practice following non-response to single antidepressant agents. Nevertheless, the scientific literature lacks preclinical studies regarding the combined administration of antidepressants across multiple behavioral measures including, but not limited to, cognition. Hence, we aimed to determine the effects of paroxetine (PAR), venlafaxine (VEN) and bupropion (BUP) alone or combined (PAR+BUP or VEN+BUP) on spatial and affective memory tasks to advance the knowledge about the combined use of antidepressants in cognition.

METHODS

Adult rats received daily injections (15 days) of PAR (20mg/kg, ip), VEN (20mg/kg, ip), BUP (20mg/kg, ip) alone or combined and were submitted to behavioral measures of spatial memory (radial-arm maze - RAM), aversive memory (passive avoidance - PA), open field (OF) and forced swimming (FST) tests.

RESULTS

In the RAM, VEN or VEN+BUP impaired learning, while short-term memory (STM) was impaired by PAR, BUP and their combination. VEN+BUP improved STM as compared to BUP. PAR impaired long-term memory (LTM). VEN or BUP alone impaired STM and long-term fear memory, whilst PAR+BUP or VEN+BUP did not induce significant alterations.

CONCLUSIONS

The effects of VEN, PAR or BUP alone and in combination on measures of memory are variable and vary as a function of the pharmacodynamics profile of each drug as well as the specific memory paradigm.