Effects of selective dopaminergic compounds on a delay-discounting task.

摘要: Impulsivity and self control are constructs used to describe what is increasingly apparent be more than one class of behaviors. Based on operant neurobiological experiments in humans animals, a growing consensus largely agrees two types impulsive behavior: choice or inter-temporal termed action behavioral disinhibition (Dalley et al., 2008; de Wit, 2009; Evenden, 1999; Perry & Carroll, Winstanley 2006). Impulsive the tendency choose rewards associated with little no delay their delivery, while refers inability withhold inhibit prepotent response. In addition these two, third component impulsivity has been proposed by some. preparation reflection impulsivity, acting before gathering processing all necessary information, argued encompass impulsive-like responding variety cognitive tasks rodent task called uncertain visual discrimination (Evenden, 1999). Impulsive typically modeled using discounting procedures that provide opportunities between smaller amount reinforcer delivered after large same longer (Ainslie, 1975). defined as reinforce over larger, delayed reinforcer, self-control reinforcer. Variants this both extensive evidence links impulse-control disorders such attention deficit hyperactivity disorder (ADHD) (Schweitzer Sulzer-Azaroff, 1995; Solanto 2001; Sonuga-Barke 1992, 1996) substance abuse (Audrain-McGovern, Baker 2003; Bickel Bobova Coffey Dom 2006; Heyman Gibbs, Johnson 2007; Jones Kirby Petry, 2004; Madden 1997, Mitchel, Monterosso Odum 2000, 2002; Petry Casarella, Reynolds, Reynolds Vuchinich Simpson, 1998). Animal research could valuable insight into other disorders. For example, altering expressed drug administrations preclinical pharmacological for possible treatment medications humans. As amphetamine methylphenidate most common pharmaceutical treatments ADHD, it not surprising have extensively studied rodents behaving tasks. Systemic reduces (i.e., animals larger at delays) (e.g., Pitts Febbo, McKinney, 2005; van Gaalen 2006), d-amphetamine shows mixed results. intact shown reduce (Floresco den Bergh Wade 2000; 2005), increase (Evenden Ryan, 1996; Helms significant effect (Stanis Uslaner Robinson, Others explored discrepancies further, noting effects may depend whether there stimulus present during (Cardinal 2000), environmental enrichment (Perry 2008), baseline level (Barbelivien 2008). Compounds selective subset five dopamine receptors administered tasks, but sometimes The nonselective antagonist flupenthixol 2000). This due D1-like antagonism D2-like antagonism, some reports show SCH 23390 increases antagonists haloperidol eticlopride another found an raclopride (Wade To authors’ knowledge, only direct agonist examined D3-preferring 7-OH-DPAT, which increased (van humans, pramipexole known individuals Parkinson’s disease, healthy controls (Hamidovic Voon 2010) As systemic injections receptor agonists unknown, we readily available male Sprague Dawley rats slight variation described Evenden Ryan (1996). drugs listed Table 1, along dose ranges pretreatment durations each. Table 1 Compounds assessed, including mechanism selectivity profile each. Selectivity difference affinity first transporter second.