The basolateral amygdala (BLA), dorsomedial prefrontal cortex (dmPFC) and dorsal hippocampus (DH) are critical elements of the neurocircuitry of drug context-induced reinstatement of cocaine-seeking; however, little is known about functional interactions between these brain regions. The present study tested the hypothesis that serial information processing by the BLA and dmPFC mediates drug context-induced cocaine-seeking, whereas the BLA and DH independently control this behaviour. Rats were trained to self-administer cocaine in a distinct environment (cocaine-paired context) followed by extinction training in a different environment (extinction context). On the test days, rats received unilateral microinfusions of baclofen + muscimol or of vehicle into the BLA and either the contralateral or ipsilateral dmPFC or DH. Cocaine-seeking behaviour (i.e. nonreinforced presses on the cocaine-associated lever) was then assessed in the cocaine-paired and extinction contexts. Following vehicle pretreatment, exposure to the cocaine-paired context reinstated extinguished cocaine-seeking behaviour. BLA-dmPFC asymmetrical inactivation attenuated cocaine-seeking behaviour relative to vehicle treatment; however, this impairment equaled that produced by ipsilateral BLA-dmPFC inactivation. Furthermore, unilateral inactivation of the BLA or dmPFC did not alter this behaviour. BLA-DH asymmetrical inactivation selectively attenuated cocaine-seeking behaviour relative to vehicle treatment whereas ipsilateral or unilateral inactivation of the BLA and DH did not alter this behaviour. These findings indicate that the BLA and DH exhibit sequential information processing within the relapse circuitry. In contrast, interactions between the BLA and dmPFC are more complex and include parallel loops of information processing and/or necessary interhemispheric input from the dmPFC to the BLA, probably in addition to direct intrahemispheric interactions.

Understanding the neurobiological underpinnings of putative memory stabilization processes that maintain context-response-cocaine associations in long-term memory and underlie contextual control over addictive behavior is of great interest from an addiction treatment perspective. Using an instrumental animal model of contextual drug relapse, we show that the protein synthesis inhibitor, anisomycin, administered into the basolateral amygdala (BLA) immediately after limited (15-or 60-min) re-exposure to a previously cocaine-paired context subsequently disrupted the ability of the previously cocaine-paired context to reinstate extinguished cocaine-seeking behavior relative to vehicle. Consistent with a BLA-mediated memory reconsolidation deficit, similar impairment in cocaine-seeking behavior was not observed in "no-reactivation" control groups that received anisomycin into the BLA after (re)exposure to either a novel unpaired or an extinctionpaired context nor in a neuroanatomical control group that received anisomycin into the posterior caudate-putamen, dorsally adjacent to the BLA, after re-exposure to the cocaine-paired context. Furthermore, anisomycin administered into the BLA after brief (5-min) or extensive (120-min) reexposure to the cocaine-paired context (which was sufficient to extinguish cocaine-seeking behavior in a vehicle control group) also failed to alter responding. Together, these findings suggest that re-exposure to a cocaine-paired context in the absence of cocaine reinforcement is sufficient to trigger memory reconsolidation processes that support future drug-seeking behavior. The presence and duration of drug-related memory reactivation critically influences and anisomycin-sensitive mechanisms in the BLA selectively control this phenomenon. These findings support the feasibility of novel pharmacotherapeutic approaches that selectively inhibit the reconsolidation of cocaine-related memories in order to prevent drug relapse.

Objectives This is the first statewide census of the product availability, price promotions, and product messaging of vape shops. Methods A comprehensive list of New Hampshire vape shops was developed through a previously validated online search method. Store audits were conducted in 55 stores between January and February 2016 using the Vape Shop Standardized Tobacco Assessment for Retail Settings (V-STARS). Results Modifiable devices and cig-alikes were sold in 92.6% and 14.6% of stores, respectively. Cross-product promotions with tobacco products were rare, and messaging promoting e-cigarettes as effective cessation devices was found in 27.3% of all stores. Candy/fruit and menthol e-liquids were most commonly found in stores, and sampling of products was available in 83.6% of stores. Ten (18.2%) stores did not have a minimum age sign posted, and self-service sampling displays were available in about one-fifth of stores. Conclusions Using V-STARS to conduct retail assessments of vape shops is feasible and is important for assessing the changing retail environment of vape shops. Vape shops distinguish themselves from traditional tobacco product retailers and offer a variety of products to customize a consumer’s experience. Regulations and effective enforcement ensuring accurate health messages is essential.

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2016-12-23T18:49:38