Research ReportsThe synthetic cathinone 3,4-methylenedioxypyrovalerone increases impulsive action in ratsHyatt, William S.a; Hirsh, Caitlin E.a; Russell, Lauren N.a; Chitre, Neha M.b; Murnane, Kevin S.b; Rice, Kenner C.c; Fantegrossi, William E.a Author Information aDepartment of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas bDepartment of Pharmaceutical Sciences, College of Pharmacy, Mercer University, Atlanta, Georgia cDrug Design and Synthesis Section, Intramural Research Program, National Institute of Drug Abuse, IRP, NIH, Baltimore, Maryland, USA Received 25 June 2019 Accepted as revised 30 December 2019 Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website, www.behaviouralpharm.com. Correspondence to William E. Fantegrossi, Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR 72207, USA, E-mail: [email protected] Behavioural Pharmacology: June 2020 - Volume 31 - Issue 4 - p 309-321 doi: 10.1097/FBP.0000000000000548 Buy SDC Metrics Abstract A previous study from our laboratory has shown that the selective catecholamine reuptake inhibitor 3,4-methylenedioxypyrovalerone (MDPV) persistently alters impulsive choice as measured by delay discounting. To further understand the proimpulsive effects of MDPV, we examined its capacity to modulate a different impulsive measure – impulsive action – using a differential reinforcement of low rates of responding task with an inter-response time of 20 s. Three groups of male, Sprague–Dawley rats (n = 6) were first tested in daily sessions to understand the acute effects of cocaine (1.0–30.0 mg/kg), MDPV (0.1–3.0 mg/kg), or saline (1.0 ml/kg) on impulsive action. Both cocaine and MDPV increased impulsive action, most notably by decreasing timing error responses and response efficiency, but MDPV was more effective than cocaine. Additionally, MDPV suppressed operant responding in two of six animals at the highest dose tested. Next, the same animals received 10 postsession injections, once every other day, of either 30.0 mg/kg cocaine, 3.0 mg/kg MDPV, or 1.0 ml/kg saline based on their treatment group. An acute dose–effect redetermination was completed following the repeated administration studies, and once again MDPV and cocaine demonstrated proimpulsive effects. Interestingly, timing error responses were decreased in both MDPV and cocaine groups after an acute saline injection, potentially indicating persistent impulsive changes following the repeated administration phase of the experiment. These studies indicate that MDPV increases impulsive action acutely and that this increase may be potentiated following a series of repeated administrations. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.