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Sample records for intravenous cocaine self-administration

  1. Influence of cue-conditioning on acquisition, maintenance and relapse of cocaine intravenous self-administration.

    Science.gov (United States)

    Deroche-Gamonet, Véronique; Piat, Frédéric; Le Moal, Michel; Piazza, Pier Vincenzo

    2002-04-01

    Conditioning theories propose that, through a Pavlovian associative process, discrete stimuli acquire the ability to elicit neural states involved in the maintenance and relapse of a drug-taking behaviour. Experimental evidence indicates that drug-related cues play a role in relapse, however, their influence on the development and maintenance of drug self-administration has been poorly investigated. In this report, we analysed the effects of a drug-associated cue light on acquisition, maintenance and reinstatement of intravenous cocaine self-administration. The results show that a cocaine-associated cue light can act as an incentive in absence of the drug, but does not directly modify drug-reinforcing effects. Contingent and non-contingent presentations of a cocaine-associated cue light reinstated an extinguished self-administration behaviour. However, regardless of whether or not a cue light was associated with cocaine infusions, rats acquire cocaine intravenous self-administration reaching the same levels of intake. Furthermore, after self-administration has been acquired in presence of the cue light, the omission of the cue light or its non-contingent presentation did not modify rat behaviour. In conclusion, our work shows that cocaine-associated explicit cues do not directly interfere with the reinforcing effects of the drug.

  2. Cocaine self-administration punished by intravenous histamine in adolescent and adult rats.

    Science.gov (United States)

    Holtz, Nathan A; Carroll, Marilyn E

    2015-06-01

    Adolescence is a transitional phase marked by a heightened vulnerability to substances of abuse. It has been hypothesized that both increased sensitivity to reward and decreased sensitivity to aversive events may drive drug-use liability during this phase. To investigate possible age-related differences in sensitivity to the aversive consequences of drug use, adolescent and adult rats were compared on self-administration of cocaine before, during, and after a 10-day period in which an aversive agent, histamine, was added to the cocaine solution. Adult and adolescent female rats were trained to self-administer intravenous cocaine (0.4 mg/kg/infusion) over 10 sessions (2 h/session; 2 sessions/day). Histamine (4 mg/kg/infusion) was then added directly into the cocaine solution for the next 10 sessions. Finally, the cocaine/histamine solution was replaced with a cocaine-only solution, and rats continued to self-administer cocaine (0.4 mg/kg) for 20 sessions. Compared with adolescent rats, adult rats showed a greater decrease in cocaine self-administration when it was punished with intravenous histamine compared with their baseline cocaine self-administration rates. These results suggest that differences in the sensitivity to negative consequences of drug use may partially explain developmental differences in drug use vulnerability.

  3. Stimulus control of cocaine self-administration

    National Research Council Canada - National Science Library

    Weiss, Stanley J; Kearns, David N; Cohn, Scott I; Schindler, Charles W; Panlilio, Leigh V

    2003-01-01

    .... Stimulus control of cocaine self-administration was generated here for the first time using multiple and chained schedules with short, frequently-alternating components--like those typically used...

  4. Diazepam alters cocaine self-administration, but not cocaine-stimulated locomotion or nucleus accumbens dopamine

    OpenAIRE

    2008-01-01

    Cocaine is known to enhance nucleus accumbens dopamine (NAcc DA), serve as a positive reinforcer and produce negative effects, such as anxiety. The influence of diazepam on cocaine intake, cocaine-stimulated behavioral activity and NAcc DA was investigated using self-administration and experimenter-administered intravenous (i.v.) cocaine. In Experiment 1, rats were pretreated with diazepam (0.25 mg/kg) or saline (0.1 ml) 30 minutes prior to 20 daily 1-hr cocaine (0.75 mg/kg/inj) self-administ...

  5. Comparison of self-administration behavior and responsiveness to drug-paired cues in rats running an alley for intravenous heroin and cocaine

    OpenAIRE

    Su, Zu-In; Wenzel, Jennifer; Baird, Rebeccah; Ettenberg, Aaron

    2010-01-01

    Rationale Evidence suggests that responsiveness to a drug-paired cue is predicted by the reinforcing magnitude of the drug during prior self-administration. It remains unclear, however, if this principle holds true when comparisons are made across drug reinforcers. Objective The current study was therefore devised to test the hypothesis that differences in the animals’ responsiveness to a cocaine- or heroin-paired cue presented during extinction would reflect differences in the patterns of pr...

  6. Cocaine self-administration increases the incentive motivational properties of the drug in rats.

    Science.gov (United States)

    Deroche, V; Le Moal, M; Piazza, P V

    1999-08-01

    A progressive increase in the frequency and intensity of drug use is one of the major behavioural phenomena characterizing the development of addiction. The nature of the drug-induced adaptations involved in this escalating drug intake remains unknown. Some theories propose that this escalation is due to a progressive decrease (tolerance) in the reinforcing or incentive effects of the drug. Alternative views posit that with chronic use the reinforcing or incentive effects of drugs increase, by a sensitization or a learning mechanism. In this report, we address the question of whether escalating cocaine intake is paralleled by an increase or a decrease in the reinforcing and incentive effects of the drug. Using the experimental model of intravenous drug self-administration with a within-session dose-response paradigm, we first studied the course of cocaine intake over 14 sessions in rats. After acquisition of cocaine self-administration, cocaine intake progressively increased at each dose tested. Then rats, previously allowed to self-administer cocaine during either six or 29 sessions, were compared in three different tests of the incentive and reinforcing effects of cocaine: cocaine-induced reinstatement of self-administration, cocaine-induced runway and cocaine-induced place conditioning. As compared with rats briefly exposed to cocaine self-administration (six sessions), rats with the longer experience (29 sessions) exhibited a higher intake of cocaine paralleled by a higher responsiveness in the cocaine-induced reinstatement and runway tests. Both groups of rats were similarly sensitive to the rewarding effects of the drug as evaluated by the threshold dose of cocaine inducing place conditioning. Our results demonstrate that escalating cocaine intake is paralleled by an increase in the motivational properties of the drug in the absence of apparent signs of tolerance to the reinforcing or incentive effects of cocaine.

  7. History of cocaine self-administration alters morphine reinforcement in the rat.

    Science.gov (United States)

    Mierzejewski, Pawel; Stefanski, Roman; Bienkowski, Przemyslaw; Kostowski, Wojciech

    2007-05-07

    It has been shown repeatedly that cocaine pre-exposure may sensitise neurochemical and behavioural responses to opioid drugs. The aim of the present study was to investigate effects of a prior history of cocaine self-administration on morphine reinforcement in the rat. Male Sprague-Dawley rats were allowed to acquire intravenous cocaine self-administration (0.3 mg/kg/infusion) for 20 days. When operant responding for cocaine had stabilised, morphine was introduced instead of cocaine in the next self-administration session. One group of cocaine-exposed rats was allowed to respond for 0.56 mg/kg/infusion of morphine (i.e. the dose which was willingly self-administered by drug-naive controls). The second group was allowed to respond for 0.056 mg/kg/infusion of morphine (i.e. the dose which did not maintain self-administration behaviour in the drug-naive rats). The subjects with the history of cocaine self-administration, in contrast to the drug-naive group, did not maintain operant responding for 0.56 mg/kg/infusion of morphine. These rats easily self-administered the ten times lower dose of the opioid (0.056 mg/kg/infusion). An opioid receptor antagonist, naltrexone (1 mg/kg i.p.) restored the positive reinforcing properties of the higher dose of morphine in the cocaine-exposed rats. Concluding, the present results suggest that prior history of cocaine self-administration sensitises rats to the positive reinforcing properties of morphine.

  8. Runway self-administration of intracerebroventricular cocaine: evidence of mixed positive and negative drug actions.

    Science.gov (United States)

    Guzman, Daniel; Ettenberg, Aaron

    2007-02-01

    In previous work from our laboratory, animals running for intravenous cocaine developed a unique approach-avoidance 'retreat behavior' that was hypothesized to result from cocaine's well documented reinforcing (positive) and anxiogenic (negative) properties. To assess the role of central mechanisms in producing cocaine's positive and negative effects, we assessed whether or not animals running a straight alley for intracerebroventricular applications of cocaine would produce a similar behavioral profile to that previously observed with intravenous applications. Retreat frequency and location were measured in male Sprague-Dawley rats trained to run an alley for one of four doses of intracerebroventricular-administered cocaine (0, 25, 50 or 100 microg cocaine/infusion). Testing involved a single trial per day over 14 consecutive days with a single infusion of cocaine delivered upon goal box entry. The 100 and 50 microg intracerebroventricular cocaine groups exhibited significantly higher retreat frequencies than the 25 and 0 microg groups and the nature and magnitude of the behavior was comparable to that previously observed with intravenous cocaine. These results suggest that the intracerebroventricular self-administration of cocaine results in mixed positive and negative consequences and therefore likely stem from the drug's actions within the central nervous system.

  9. Peer influences on drug self-administration: social facilitation and social inhibition of cocaine intake in male rats.

    Science.gov (United States)

    Smith, Mark A

    2012-11-01

    One problem facing animal models of intravenous drug self-administration, particularly those examining social manipulations, is that subjects must be removed from the home environment and separated from cagemates during testing. This represents a limitation of animal models because it fails to capture the complex social environments in which drug use often occur. The aim of this study was to examine intravenous cocaine self-administration in isolated and socially housed rats, with the caveat that the socially housed subjects lived together 24 h/day, including during daily self-administration sessions. As a secondary aim, the study examined the impact of a companion that also self-administered cocaine versus a companion without access to cocaine. Male rats were obtained at weaning and reared in isolated or pair-housed conditions for 6 weeks. Rats were then implanted with intravenous catheters and transferred to custom-built operant conditioning chambers that served as home cages for the remainder of the study. For some socially housed subjects, both rats had simultaneous access to cocaine; for others, only one rat of the pair had access to cocaine. Cocaine self-administration was facilitated in socially housed rats if both members of the pair had access to cocaine; however, cocaine self-administration was inhibited if only one rat of the pair had access to cocaine. These data indicate that the self-administration behavior of a peer, not merely the presence of a peer, determines whether cocaine self-administration is facilitated or inhibited by social contact.

  10. Varenicline effects on cocaine self administration and reinstatement behavior.

    Science.gov (United States)

    Guillem, Karine; Peoples, Laura L

    2010-03-01

    This study tested the effects of the nicotine addiction treatment varenicline on cocaine self administration (SA) and reinstatement. In one SA experiment, rats were trained to self-administer cocaine (0.75 mg/kg/infusion). Thereafter, daily SA sessions continued as before except that every fourth session was preceded by a presession injection of varenicline (0.0, 0.3, 1.0 and 2.0 mg/kg, SC, 50-min presession). In three reinstatement experiments, animals were exposed sequentially to SA training, extinction training, and several reinstatement test sessions. In two of the reinstatement experiments, cocaine-seeking was reinstated by presentation of cocaine-predictive cues at the onset of the test session (cue reinstatement). In a third reinstatement experiment, cocaine-seeking was reinstated by a presession injection of cocaine (drug reinstatement). Each reinstatement session was preceded by an injection of either vehicle or varenicline (dose range of 0.1-2.0 mg/kg). The SA and reinstatement experiments showed that low-dose varenicline decreases reinstatement behavior, without significantly affecting cocaine SA. In contrast, high-dose varenicline increases reinstatement of cocaine-directed behavior and decreases cocaine SA. A control study showed that sucrose-directed behavior is unaltered by varenicline. On the basis of these findings, low-varenicline doses might decrease relapse in cocaine-addicted individuals, but high doses of varenicline might have the opposite effect.

  11. Adolescent risk taking, cocaine self-administration, and striatal dopamine signaling

    National Research Council Canada - National Science Library

    Mitchell, Marci R; Weiss, Virginia G; Beas, B Sofia; Morgan, Drake; Bizon, Jennifer L; Setlow, Barry

    2014-01-01

    ... (the Risky Decision-making Task; RDT) was used to determine whether individual differences in risk taking during adolescence predict later propensity for cocaine self-administration and/or whether cocaine self-administration causes...

  12. Cocaine self-administration disrupts mesolimbic dopamine circuit function and attenuates dopaminergic responsiveness to cocaine.

    Science.gov (United States)

    Siciliano, Cody A; Ferris, Mark J; Jones, Sara R

    2015-08-01

    Dopaminergic projections from the ventral midbrain to the nucleus accumbens (NAc) have long been implicated in encoding associations between reward availability and environmental stimuli. As such, this circuit is instrumental in guiding behaviors towards obtaining maximal rewards based on previous experience. Cocaine acts on the dopamine system to exert its reinforcing effects and it is thought that cocaine-induced dysregulation of dopamine neurotransmission contributes to the difficulty that cocaine addicts exhibit in selecting environmentally appropriate behaviors. Here we used cocaine self-administration combined with in vivo fast scan cyclic voltammetry in anesthetised rats to examine the function of the ventral tegmental area to NAc projection neurons. Over 5 days of cocaine self-administration (fixed-ratio 1; 1.5 mg/kg/injection; 40 injections/day), animals increased their rate of intake. Following cocaine self-administration, there was a marked reduction in ventral tegmental area-stimulated NAc dopamine release. Additionally, there was a decreased augmentation of stimulated dopamine overflow in response to a cocaine challenge. These findings demonstrate that cocaine induces a hypodopaminergic state, which may contribute to the inflexible drug-taking and drug-seeking behaviors observed in cocaine abusers. Additionally, tolerance to the ability of cocaine to elevate dopamine may lead to increased cocaine intake in order to overcome decreased effects, another hallmark of cocaine abuse. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  13. Single prolonged stress effects on sensitization to cocaine and cocaine self-administration in rats

    Science.gov (United States)

    Eagle, Andrew L.; Singh, Robby; Kohler, Robert J.; Friedman, Amy L.; Liebowitz, Chelsea P.; Galloway, Matthew P.; Enman, Nicole M.; Jutkiewicz, Emily M.; Perrine, Shane A.

    2017-01-01

    Posttraumatic stress disorder (PTSD) is often comorbid with substance use disorders (SUD). Single prolonged stress (SPS) is a well-validated rat model of PTSD that provides a framework to investigate drug-induced behaviors as a preclinical model of the comorbidity. We hypothesized that cocaine sensitization and self-administration would be increased following exposure to SPS. Male Sprague–Dawley rats were exposed to SPS or control treatment. After SPS, cocaine (0,10 or 20mg/kg, i.p.) was administered for 5 consecutive days and locomotor activity was measured. Another cohort was assessed for cocaine self-administration (0.1 or 0.32 mg/kg/i.v.) after SPS. Rats were tested for acquisition, extinction and cue-induced reinstatement behaviors. Control animals showed a dose-dependent increase in cocaine-induced locomotor activity after acute cocaine whereas SPS rats did not. Using a sub-threshold sensitization paradigm, control rats did not exhibit enhanced locomotor activity at Day 5 and therefore did not develop behavioral sensitization, asexpected. However, compared to control ratson Day 5 the locomotor response to 20mg/kg repeated cocaine was greatly enhanced in SPS-treated rats, which exhibited enhanced cocaine locomotor sensitization. The effect of SPS on locomotor activity was unique in that SPS did not modify cocaine self-administration behaviors under a simple schedule of reinforcement. These data show that SPS differentially affects cocaine-mediated behaviors causing no effect to cocaine self-administration, under a simple schedule of reinforcement, but significantly augmenting cocaine locomotor sensitization. These results suggest that SPS shares common neurocircuitry with stimulant-induced plasticity, but dissociable from that underlying psychostimulant-induced reinforcement. PMID:25712697

  14. Behavioral momentum of cocaine self-administration: effects of frequency of reinforcement on resistance to extinction.

    Science.gov (United States)

    Quick, Stacey L; Shahan, Timothy A

    2009-07-01

    Persistent drug seeking is a defining property of substance abuse and is generally thought to depend, in part, on exposure to drug-associated contexts. Behavioral momentum theory provides a set of methods and a theoretical framework for understanding how stimulus contexts contribute to the persistence of operant behavior. Earlier research has extended behavioral momentum theory to alcohol self-administration, but not to intravenous drug self-administration. This experiment extended behavioral momentum theory to cocaine self-administration by examining the effects of frequency of cocaine reinforcement in a context on resistance to extinction. Rats self-administered 0.32 mg/kg infusions of cocaine in a multiple schedule of reinforcement arranging two distinct contexts. Responding in a Rich context was reinforced by cocaine infusions at a higher frequency (i.e. variable interval 120 s) and in a Lean context at a lower frequency (variable interval 360 s). After establishment of responding in the two contexts, resistance to extinction was examined. Preextinction response rates for cocaine were similar in the Rich and Lean contexts. Nonetheless, relative resistance to extinction was greater in the Rich context than in the Lean context. The difference in resistance to extinction in the two contexts was well described by a quantitative model of behavioral momentum. These results suggest that the frequency of drug reinforcement in a context contributes to the persistence of drug seeking in that context, and that behavioral momentum theory might be useful for understanding how drug-associated contexts contribute to the persistence of drug seeking.

  15. The Infralimbic Cortex Regulates the Consolidation of Extinction after Cocaine Self-Administration

    Science.gov (United States)

    LaLumiere, Ryan T.; Niehoff, Kate E.; Kalivas, Peter W.

    2010-01-01

    The infralimbic cortex (IL) regulates the consolidation of extinction learning for fear conditioning. Whether the IL influences the consolidation of extinction learning for cocaine self-administration is unknown. To address this issue, male Sprague-Dawley rats underwent 2 wk of cocaine self-administration followed by extinction training. On the…

  16. Glutamatergic Mechanisms of Comorbidity Between Acute Stress and Cocaine Self-administration

    Science.gov (United States)

    Garcia-Keller, Constanza; Kupchik, Yonatan; Gipson, Cassandra D; Brown, Robyn M; Spencer, Sade; Bollati, Flavia; Esparza, Maria A; Roberts-Wolfe, Doug; Heinsbroek, Jasper; Bobadilla, Ana-Clara; Cancela, Liliana M; Kalivas, Peter W

    2015-01-01

    There is substantial comorbidity between stress disorders and substance use disorders (SUDs), and acute stress augments the locomotor stimulant effect of cocaine in animal models. Here we endeavor to understand the neural underpinnings of comorbid stress disorders and drug use by determining if the glutamatergic neuroadaptations that characterize cocaine self-administration are induced by acute stress. Rats were exposed to acute (2 h) immobilization stress and 3 weeks later the nucleus accumbens core was examined for changes in glutamate transport, glutamate mediated synaptic currents, and dendritic spine morphology. We also determined if acute stress potentiated the acquisition of cocaine self-administration. Acute stress produced an enduring reduction in glutamate transport, and potentiated excitatory synapses on medium spiny neurons. Acute stress also augmented the acquisition of cocaine self-administration. Importantly, by restoring glutamate transport in the accumbens core with ceftriaxone the capacity of acute stress to augment the acquisition of cocaine self-administration was abolished. Similarly, ceftriaxone treatment prevented stress-induced potentiation of cocaine-induced locomotor activity. However, ceftriaxone did not reverse stress-induced synaptic potentiation, indicating that this effect of stress exposure did not underpin the increased acquisition of cocaine self-administration. Reversing acute stress-induced vulnerability to self-administer cocaine by normalizing glutamate transport poses a novel treatment possibility for reducing comorbid SUDs in stress disorders. PMID:26821978

  17. N-Acetylcysteine reduces cocaine-cue attentional bias and differentially alters cocaine self-administration based on dosing order.

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    Levi Bolin, B; Alcorn, Joseph L; Lile, Joshua A; Rush, Craig R; Rayapati, Abner O; Hays, Lon R; Stoops, William W

    2017-09-01

    Disrupted glutamate homeostasis is thought to contribute to cocaine-use disorder, in particular, by enhancing the incentive salience of cocaine stimuli. n-Acetylcysteine might be useful in cocaine-use disorder by normalizing glutamate function. In prior studies, n-acetylcysteine blocked the reinstatement of cocaine seeking in laboratory animals and reduced the salience of cocaine stimuli and delayed relapse in humans. The present study determined the ability of maintenance on n-acetylcysteine (0 or 2400mg/day, counterbalanced) to reduce the incentive salience of cocaine stimuli, as measured by an attentional bias task, and attenuate intranasal cocaine self-administration (0, 30, and 60mg). Fourteen individuals (N=14) who met criteria for cocaine abuse or dependence completed this within-subjects, double-blind, crossover-design study. Cocaine-cue attentional bias was greatest following administration of 0mg cocaine during placebo maintenance, and was attenuated by n-acetylcysteine. Cocaine maintained responding during placebo and n-acetylcysteine maintenance, but the reinforcing effects of cocaine were significantly attenuated across both maintenance conditions in participants maintained on n-acetylcysteine first compared to participants maintained on placebo first. These results collectively suggest that a reduction in the incentive salience of cocaine-related stimuli during n-acetylcysteine maintenance may be accompanied by reductions in cocaine self-administration. These results are in agreement with, and link, prior preclinical and clinical trial results suggesting that n-acetylcysteine might be useful for preventing cocaine relapse by attenuating the incentive salience of cocaine cues. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Neural Changes Developed during the Extinction of Cocaine Self-Administration Behavior

    Directory of Open Access Journals (Sweden)

    Nuria del Olmo

    2011-10-01

    Full Text Available The high rate of recidivism in cocaine addiction after prolonged periods of abstinence poses a significant problem for the effective treatment of this condition. Moreover, the neurobiological basis of this relapse phenomenon remains poorly understood. In this review, we will discuss the evidence currently available regarding the neurobiological changes during the extinction of cocaine self-administration. Specifically, we will focus on alterations in the dopaminergic, opioidergic, glutamatergic, cholinergic, serotoninergic and CRF systems described in self-administration experiments and extinction studies after chronic cocaine administration. We will also discuss the differences related to contingent versus non-contingent cocaine administration, which highlights the importance of environmental cues on drug effects and extinction. The findings discussed in this review may aid the development of more effective therapeutic approaches to treat cocaine relapse.

  19. Neural Changes Developed during the Extinction of Cocaine Self-Administration Behavior

    Science.gov (United States)

    Higuera-Matas, Alejandro; Miguens, Miguel; del Olmo, Nuria; García-Lecumberri, Carmen; Ambrosio, Emilio

    2011-01-01

    The high rate of recidivism in cocaine addiction after prolonged periods of abstinence poses a significant problem for the effective treatment of this condition. Moreover, the neurobiological basis of this relapse phenomenon remains poorly understood. In this review, we will discuss the evidence currently available regarding the neurobiological changes during the extinction of cocaine self-administration. Specifically, we will focus on alterations in the dopaminergic, opioidergic, glutamatergic, cholinergic, serotoninergic and CRF systems described in self-administration experiments and extinction studies after chronic cocaine administration. We will also discuss the differences related to contingent versus non-contingent cocaine administration, which highlights the importance of environmental cues on drug effects and extinction. The findings discussed in this review may aid the development of more effective therapeutic approaches to treat cocaine relapse. PMID:26791639

  20. Transforming growth factor beta receptor 1 is increased following abstinence from cocaine self-administration, but not cocaine sensitization.

    Directory of Open Access Journals (Sweden)

    Amy M Gancarz-Kausch

    Full Text Available The addicted phenotype is characterized as a long-lasting, chronically relapsing disorder that persists following long periods of abstinence, suggesting that the underlying molecular changes are stable and endure for long periods even in the absence of drug. Here, we investigated Transforming Growth Factor-Beta Type I receptor (TGF-β R1 expression in the nucleus accumbens (NAc following periods of withdrawal from cocaine self-administration (SA and a sensitizing regimen of non-contingent cocaine. Rats were exposed to either (i repeated systemic injections (cocaine or saline, or (ii self-administration (cocaine or saline and underwent a period of forced abstinence (either 1 or 7 days of drug cessation. Withdrawal from cocaine self-administration resulted in an increase in TGF-β R1 protein expression in the NAc compared to saline controls. This increase was specific for volitional cocaine intake as no change in expression was observed following a sensitizing regimen of experimenter-administered cocaine. These findings implicate TGF-β signaling as a novel potential therapeutic target for treating drug addiction.

  1. Social Status in Monkeys: Effects of Social Confrontation on Brain Function and Cocaine Self-Administration.

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    Gould, Robert W; Czoty, Paul W; Porrino, Linda J; Nader, Michael A

    2017-04-01

    Individual differences in response to social stress and environmental enrichment may contribute to variability in response to behavioral and pharmacological treatments for drug addiction. In monkeys, social status influences the reinforcing effects of cocaine and the effects of some drugs on cocaine self-administration. In this study, we used male cynomolgus macaques (n=15) living in established social groups to examine the effects of social confrontation on the reinforcing effects of cocaine using a food-drug choice procedure. On the test day, a dominant or subordinate monkey was removed from his homecage and placed into another social pen; 30 min later he was studied in a cocaine-food choice paradigm. For the group, following social confrontation, sensitivity to cocaine reinforcement was significantly greater in subordinate monkeys compared with dominant animals. Examining individual-subject data revealed that for the majority of monkeys (9/15), serving as an intruder in another social group affected cocaine self-administration and these effects were dependent on the social rank of the monkey. For subordinate monkeys, sensitivity to the reinforcing effects of cocaine increased while sensitivity decreased in dominant monkeys. To investigate potential mechanisms mediating these effects, brain glucose metabolism was studied in a subset of monkeys (n=8) using [(18)F]fluorodeoxyglucose ([(18)F]FDG) with positron emission tomography. Dominant and subordinate monkeys displayed distinctly different patterns of brain glucose metabolism in their homecage, including areas associated with vigilance and stress/anxiety, respectively, and during social confrontation. These data demonstrate that, depending on an individual's social status, the same social experience can have divergent effects on brain function and cocaine self-administration. These phenotypic differences in response to social conditions support a personalized treatment approach to cocaine addiction.

  2. Cocaine Self-Administration Produces Long-Lasting Alterations in Dopamine Transporter Responses to Cocaine

    OpenAIRE

    Siciliano, Cody A.; Fordahl, Steve C.; Jones, Sara R.

    2016-01-01

    Cocaine addiction is a debilitating neuropsychiatric disorder characterized by uncontrolled cocaine intake, which is thought to be driven, at least in part, by cocaine-induced deficits in dopamine system function. A decreased ability of cocaine to elevate dopamine levels has been repeatedly observed as a consequence of cocaine use in humans, and preclinical work has highlighted tolerance to cocaine's effects as a primary determinant in the development of aberrant cocaine taking behaviors. Her...

  3. Effects of baclofen and raclopride on reinstatement of cocaine self-administration in the rat.

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    Froger-Colléaux, Christelle; Castagné, Vincent

    2016-04-15

    At present there is no satisfactory treatment against relapse of drug-seeking behavior. Relapse can be modeled in laboratory animals using reinstatement procedures, whereby previously extinguished self-administration for a drug is reinstated by different factors, such as exposure to cues or drug priming. It is thought that activation of gamma-aminobutyric acid (GABA) B receptor complexes could represent a promising approach to pharmacotherapy for diminishing relapse potential with drugs possessing reinforcing properties. The effects of baclofen (a prototypic GABAB receptor agonist) on cue-induced cocaine reinstatement were evaluated in the rat with or without a priming injection of cocaine. The effects of raclopride (an antagonist of dopamine D2 receptors) were also evaluated. Cue-induced reinstatement under vehicle resulted in a significant increase in the number of presses on the active lever, as compared with extinction lever responding. This effect was accentuated in rats receiving a priming injection of cocaine (cocaine-plus-cue-induced reinstatement). Baclofen, at doses without effects on food-motivated operant behavior (2.5 and 5mg/kg i.p.), dose-dependently decreased the number of active lever presses during cue-induced reinstatement. Baclofen had slightly weaker effects on cocaine-plus-cue-induced reinstatement. Raclopride (0.08 and 0.15 mg/kg s.c.) had similar effects against cue-induced reinstatement although it failed to inhibit cocaine-plus-cue-induced reinstatement at the lower dose. Baclofen dose-dependently and selectively decreased reinstatement of cocaine self-administration. The data obtained provide support for the potential anti-craving efficacy of baclofen in the treatment of cocaine drug-seeking.

  4. Effects of chronic methylphenidate on cocaine self-administration under a progressive-ratio schedule of reinforcement in rhesus monkeys.

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    Czoty, Paul W; Martelle, Susan E; Gould, Robert W; Nader, Michael A

    2013-06-01

    It has been hypothesized that drugs that serve as substrates for dopamine (DA) and norepinephrine (NE) transporters may be more suitable medications for cocaine dependence than drugs that inhibit DA and NE uptake by binding to transporters. Previous studies have shown that the DA/NE releaser d-amphetamine can decrease cocaine self-administration in preclinical and clinical studies. The present study examined the effects of methylphenidate (MPD), a DA uptake inhibitor, for its ability to decrease cocaine self-administration under conditions designed to reflect clinically relevant regimens of cocaine exposure and pharmacotherapy. Each morning, rhesus monkeys pressed a lever to receive food pellets under a fixed-ratio 50 schedule of reinforcement; cocaine was self-administered under a progressive-ratio schedule of reinforcement in the evening. After cocaine (0.003-0.56 mg/kg per injection, i.v.) dose-response curves were determined, self-administration sessions were suspended and MPD (0.003-0.0056 mg/kg per hour, i.v.; or 1.0-9.0 mg/kg p.o., b.i.d.) was administered for several weeks. A cocaine self-administration session was conducted every 7 days. When a MPD dose was reached that either persistently decreased cocaine self-administration or produced disruptive effects, the cocaine dose-effect curve was re-determined. In most cases, MPD treatment either produced behaviorally disruptive effects or increased cocaine self-administration; it took several weeks for these effects to dissipate. These data are consistent with the largely negative results of clinical trials with MPD. In contrast to the positive effects with the monoamine releaser d-amphetamine under identical conditions, these results do not support use of monoamine uptake inhibitors like MPD as a medication for cocaine dependence.

  5. METHYLPHENIDATE ENHANCES THE ABUSE-RELATED BEHAVIORAL EFFECTS OF NICOTINE IN RATS: INTRAVENOUS SELF-ADMINISTRATION, DRUG DISCRIMINATION AND LOCOMOTOR CROSS-SENSITIZATION

    OpenAIRE

    Wooters, Thomas E.; Neugebauer, Nichole M.; Rush, Craig R.; Bardo, Michael T.

    2007-01-01

    Stimulant drugs, including d-amphetamine, cocaine and methylphenidate, increase cigarette smoking in controlled human laboratory experiments. Although the mechanism(s) underlying this effect are unknown, it is possible that stimulants may enhance directly the abuse-related effects of nicotine. In the present study, we characterized the behavioral pharmacological interactions between methylphenidate and nicotine in the intravenous self-administration, drug discrimination and locomotor cross-se...

  6. Novelty seeking, incentive salience and acquisition of cocaine self-administration in the rat.

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    Beckmann, Joshua S; Marusich, Julie A; Gipson, Cassandra D; Bardo, Michael T

    2011-01-01

    It has been suggested that incentive salience plays a major role in drug abuse and the development of addiction. Additionally, novelty seeking has been identified as a significant risk factor for drug abuse. However, how differences in the readiness to attribute incentive salience relate to novelty seeking and drug abuse vulnerability has not been explored. The present experiments examined how individual differences in incentive salience attribution relate to novelty seeking and acquisition of cocaine self-administration in a preclinical model. Rats were first assessed in an inescapable novelty task and a novelty place preference task (measures of novelty seeking), followed by a Pavlovian conditioned approach task for food (a measure of incentive salience attribution). Rats then were trained to self-administer cocaine (0.3 or 1.0 mg/kg/infusion) using an autoshaping procedure. The results demonstrate that animals that attributed incentive salience to a food-associated cue were higher novelty seekers and acquired cocaine self-administration more quickly at the lower dose. The results suggest that novelty-seeking behavior may be a mediator of incentive salience attribution and that incentive salience magnitude may be an indicator of drug reward.

  7. Differential Control of Cocaine Self-Administration by GABAergic and Glutamatergic CB1 Cannabinoid Receptors.

    Science.gov (United States)

    Martín-García, Elena; Bourgoin, Lucie; Cathala, Adeline; Kasanetz, Fernando; Mondesir, Miguel; Gutiérrez-Rodriguez, Ana; Reguero, Leire; Fiancette, Jean-François; Grandes, Pedro; Spampinato, Umberto; Maldonado, Rafael; Piazza, Pier Vincenzo; Marsicano, Giovanni; Deroche-Gamonet, Véronique

    2016-08-01

    The type 1 cannabinoid receptor (CB1) modulates numerous neurobehavioral processes and is therefore explored as a target for the treatment of several mental and neurological diseases. However, previous studies have investigated CB1 by targeting it globally, regardless of its two main neuronal localizations on glutamatergic and GABAergic neurons. In the context of cocaine addiction this lack of selectivity is critical since glutamatergic and GABAergic neuronal transmission is involved in different aspects of the disease. To determine whether CB1 exerts different control on cocaine seeking according to its two main neuronal localizations, we used mutant mice with deleted CB1 in cortical glutamatergic neurons (Glu-CB1) or in forebrain GABAergic neurons (GABA-CB1). In Glu-CB1, gene deletion concerns the dorsal telencephalon, including neocortex, paleocortex, archicortex, hippocampal formation and the cortical portions of the amygdala. In GABA-CB1, it concerns several cortical and non-cortical areas including the dorsal striatum, nucleus accumbens, thalamic, and hypothalamic nuclei. We tested complementary components of cocaine self-administration, separating the influence of primary and conditioned effects. Mechanisms underlying each phenotype were explored using in vivo microdialysis and ex vivo electrophysiology. We show that CB1 expression in forebrain GABAergic neurons controls mouse sensitivity to cocaine, while CB1 expression in cortical glutamatergic neurons controls associative learning processes. In accordance, in the nucleus accumbens, GABA-CB1 receptors control cocaine-induced dopamine release and Glu-CB1 receptors control AMPAR/NMDAR ratio; a marker of synaptic plasticity. Our findings demonstrate a critical distinction of the altered balance of Glu-CB1 and GABA-CB1 activity that could participate in the vulnerability to cocaine abuse and addiction. Moreover, these novel insights advance our understanding of CB1 neuropathophysiology.

  8. The glucagon-like peptide 1 (GLP-1) receptor agonist exendin-4 reduces cocaine self-administration in mice.

    Science.gov (United States)

    Sørensen, Gunnar; Reddy, India A; Weikop, Pia; Graham, Devon L; Stanwood, Gregg D; Wortwein, Gitta; Galli, Aurelio; Fink-Jensen, Anders

    2015-10-01

    Glucagon-like peptide 1 (GLP-1) analogues are used for the treatment of type 2 diabetes. The ability of the GLP-1 system to decrease food intake in rodents has been well described and parallels results from clinical trials. GLP-1 receptors are expressed in the brain, including within the ventral tegmental area (VTA) and the nucleus accumbens (NAc). Dopaminergic neurons in the VTA project to the NAc, and these neurons play a pivotal role in the rewarding effects of drugs of abuse. Based on the anatomical distribution of GLP-1 receptors in the brain and the well-established effects of GLP-1 on food reward, we decided to investigate the effect of the GLP-1 analogue exendin-4 on cocaine- and dopamine D1-receptor agonist-induced hyperlocomotion, on acute and chronic cocaine self-administration, on cocaine-induced striatal dopamine release in mice and on cocaine-induced c-fos activation. Here, we report that GLP-1 receptor stimulation reduces acute and chronic cocaine self-administration and attenuates cocaine-induced hyperlocomotion. In addition, we show that peripheral administration of exendin-4 reduces cocaine-induced elevation of striatal dopamine levels and striatal c-fos expression implicating central GLP-1 receptors in these responses. The present results demonstrate that the GLP-1 system modulates cocaine's effects on behavior and dopamine homeostasis, indicating that the GLP-1 receptor may be a novel target for the pharmacological treatment of drug addiction.

  9. Cocaine self-administration in mice with forebrain knock-down of trpc5 ion channels [v1; ref status: indexed, http://f1000r.es/pb

    Directory of Open Access Journals (Sweden)

    Matthew B Pomrenze

    2013-02-01

    Full Text Available Canonical transient receptor potential (TRPC channels are a family of non-selective cation channels that play a crucial role in modulating neuronal excitability due to their involvement in intracellular Ca2+ regulation and dendritic growth. TRPC5 channels a are one of the two most prevalent TRPC channels in the adult rodent brain; b are densely expressed in deep layer pyramidal neurons of the prefrontal cortex (PFC; and c modulate neuronal persistent activity necessary for working memory and attention. In order to evaluate the causal role of TRPC5 in motivation/reward-related behaviors, conditional forebrain TRPC5 knock-down (trpc5-KD mice were generated and trained to nose-poke for intravenous cocaine. Here we present a data set containing the first 6 days of saline or cocaine self-administration in wild type (WT and trpc5-KD mice. In addition, we also present a data set showing the dose-response to cocaine after both groups had achieved similar levels of cocaine self-administration. Compared to WT mice, trpc5-KD mice exhibited an apparent increase in self-administration on the first day of cocaine testing without prior operant training. There were no apparent differences between WT and trpc5-KD mice for saline responding on the first day of training. Both groups showed similar dose-response sensitivity to cocaine after several days of achieving similar levels of cocaine intake.

  10. Inactivation of the central nucleus of the amygdala reduces the effect of punishment on cocaine self-administration in rats.

    Science.gov (United States)

    Xue, YueQiang; Steketee, Jeffery D; Sun, WenLin

    2012-03-01

    Continued cocaine use despite the negative consequences is a hallmark of cocaine addiction. One such consequence is punishment, which is often used by society to curb cocaine use. Unfortunately, we know little about the mechanism involved in regulation by punishment of cocaine use. The fact that cocaine addicts continue to use cocaine despite potentially severe punishment suggests that the mechanism may be impaired. Such impairment is expected to critically contribute to compulsive cocaine use. This study was aimed at testing the hypothesis that the central nucleus of the amygdala (CeN) plays a critical role in such regulation. To this end, rats were trained to press a lever to self-administer cocaine under a chained schedule: a response on one lever (cocaine-seeking lever) led to access to the other lever (cocaine-taking lever), on which a response was reinforced by cocaine and cues. Thereafter, responses on the seeking lever were punished by footshock with a probability of 0.5. Cocaine self-administration (SA) was significantly suppressed by punishment in an intensity-dependent manner. Interestingly, rats trained with daily 6-h (extended access) but not 2-h (limited access) sessions showed resistance to the lower intensity of punishment. Inactivation of the CeN induced a robust anti-punishment effect in both groups. These data provided evidence that the CeN is a critical neural substrate involved in regulation by punishment of cocaine SA. Rats with a history of extended cocaine SA appeared to be less sensitive to punishment. The decreased sensitivity could result from the neuroplastic changes induced by extended cocaine SA in the CeN.

  11. Extinction of cocaine self-administration reveals functionally and temporally distinct dopaminergic signals in the nucleus accumbens.

    Science.gov (United States)

    Stuber, Garret D; Wightman, R Mark; Carelli, Regina M

    2005-05-19

    While Pavlovian and operant conditioning influence drug-seeking behavior, the role of rapid dopamine signaling in modulating these processes is unknown. During self-administration of cocaine, two dopaminergic signals, measured with 100 ms resolution, occurred immediately before and after the lever press (termed pre- and post-response dopamine transients). Extinction of self-administration revealed that these two signals were functionally distinct. Pre-response transients, which could reflect the motivation to obtain the drug, did not decline during extinction. Remarkably, post-response dopamine transients attenuated as extinction progressed, suggesting that they encode the learned association between environmental cues and cocaine. A third type of dopamine transient, not time locked to overt stimuli, decreased in frequency during extinction and correlated with calculated cocaine concentrations. These results show that dopamine release transients involved in different aspects of cocaine self-administration are highly plastic--differentially governed by motivation, learned associations linked with environmental stimuli, and the pharmacological actions of cocaine.

  12. Effects of active anti-methamphetamine vaccination on intravenous self-administration in rats.

    Science.gov (United States)

    Miller, M L; Aarde, S M; Moreno, A Y; Creehan, K M; Janda, K D; Taffe, M A

    2015-08-01

    d-Methamphetamine (METH) addiction is a serious public health concern for which successful treatment remains elusive. Immunopharmacotherapy has been shown to attenuate locomotor and thermoregulatory effects of METH. The current study investigated whether active vaccination against METH could alter intravenous METH self-administration in rats. Male Sprague-Dawley rats (Experiment 1: N=24; Experiment 2: N=18) were vaccinated with either a control keyhole-limpet hemocyanin conjugate vaccine (KLH) or a candidate anti-METH vaccine (MH6-KLH) or. Effects of vaccination on the acquisition of METH self-administration under two dose conditions (0.05, 0.1mg/kg/inf) and post-acquisition dose-substitution (0, 0.01, 0.05, 0.20mg/kg/inf, Experiment 1; 0.01, 0.05, 0.10, 0.15mg/kg/inf, Experiment 2) during steady-state responding were investigated. Plasma METH concentrations were determined 30min after an acute challenge dose of 3.2mg/kg METH. Active vaccination inhibited the acquisition of METH self-administration under the 0.1mg/kg/inf dose condition, with 66% of the MH6-KLH-vaccinated rats compared to 100% of the controls reaching criteria, and produced transient and dose-dependent effects on self-administration during the maintenance phase. Under the 0.05mg/kg/inf dose condition, MH6-KLH-vaccinated rats initially self-administered more METH than controls, but then self-administration decreased across the acquisition phase relative to controls; a subsequent dose-response assessment confirmed that MH6-KLH-vaccinated rats failed to acquire METH self-administration. Finally, plasma METH concentrations were higher in MH6-KLH-vaccinated rats compared to controls after an acute METH challenge, and these were positively correlated with antibody titers. These data demonstrate that active immunopharmacotherapy for METH attenuates the acquisition of METH self-administration. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Gene expression changes in the medial prefrontal cortex and nucleus accumbens following abstinence from cocaine self-administration

    Directory of Open Access Journals (Sweden)

    Morgan Drake

    2010-02-01

    Full Text Available Abstract Background Many studies of cocaine-responsive gene expression have focused on changes occurring during cocaine exposure, but few studies have examined the persistence of these changes with cocaine abstinence. Persistent changes in gene expression, as well as alterations induced during abstinence may underlie long-lasting drug craving and relapse liability. Results Whole-genome expression analysis was conducted on a rat cocaine binge-abstinence model that has previously been demonstrated to engender increased drug seeking and taking with abstinence. Gene expression changes in two mesolimbic terminal fields (mPFC and NAc were identified in a comparison of cocaine-naïve rats with rats after 10 days of cocaine self-administration followed by 1, 10, or 100 days of enforced abstinence (n = 6-11 per group. A total of 1,461 genes in the mPFC and 414 genes in the NAc were altered between at least two time points (ANOVA, p Conclusions Together, these changes help to illuminate processes and networks involved in abstinence-induced behaviors, including synaptic plasticity, MAPK signaling, and TNF signaling.

  14. Reduction of Cocaine Self-Administration and D3 Receptor-Mediated Behavior by Two Novel Dopamine D3 Receptor-Selective Partial Agonists, OS-3-106 and WW-III-55

    Science.gov (United States)

    Cheung, Timothy H. C.; Loriaux, Amy L.; Weber, Suzanne M.; Chandler, Kayla N.; Lenz, Jeffrey D.; Schaan, Romina F.; Mach, Robert H.; Luedtke, Robert R.

    2013-01-01

    Dopamine D3 receptor (D3R)-selective compounds may be useful medications for cocaine dependence. In this study, we identified two novel arylamide phenylpiperazines, OS-3-106 and WW-III-55, as partial agonists at the D3R in the adenylyl cyclase inhibition assay. OS-3-106 and WW-III-55 have 115- and 862-fold D3R:D2 receptor (D2R) binding selectivity, respectively. We investigated their effects (0, 3, 5.6, or 10 mg/kg) on operant responding by using a multiple variable-interval (VI) 60-second schedule that alternated components with sucrose reinforcement and components with intravenous cocaine reinforcement (0.375 mg/kg). Additionally, we evaluated the effect of OS-3-106 (10 mg/kg) on the dose-response function of cocaine self-administration and the effect of WW-III-55 (0–5.6 mg/kg) on a progressive ratio schedule with either cocaine or sucrose reinforcement. Both compounds were also examined for effects on locomotion and yawning induced by a D3R agonist. OS-3-106 decreased cocaine and sucrose reinforcement rates, increased latency to first response for cocaine but not sucrose, and downshifted the cocaine self-administration dose-response function. WW-III-55 did not affect cocaine self-administration on the multiple-variable interval schedule, but it reduced cocaine and sucrose intake on the progressive ratio schedule. Both compounds reduced locomotion at doses that reduced responding, and both compounds attenuated yawning induced by low doses of 7-OH-DPAT (a D3R-mediated behavior), but neither affected yawning on the descending limb of the 7-OH-DPAT dose-response function (a D2R-mediated behavior). Therefore, both compounds blocked a D3R-mediated behavior. However, OS-3-106 was more effective in reducing cocaine self-administration. These findings support D3Rs, and possibly D2Rs, as targets for medications aimed at reducing the motivation to seek cocaine. PMID:24018640

  15. Anisomycin in the medial prefrontal cortex reduces reconsolidation of cocaine-associated memories in the rat self-administration model.

    Science.gov (United States)

    Sorg, Barbara A; Todd, Ryan P; Slaker, Megan; Churchill, Lynn

    2015-05-01

    We tested the hypothesis that infusion of anisomycin into the medial prefrontal cortex (mPFC) disrupts the reconsolidation of a cocaine-associated memory in the rat cocaine self-administration model. Male Sprague-Dawley rats were trained to lever press for cocaine self-administration (0.5 mg/kg/infusion) along with a cue light presentation on an FR1 followed by an FR3 schedule of reinforcement for 2 h/day. Rats were then given extinction sessions or an equivalent forced abstinence period followed by a 5 min memory reactivation session during which time they received an ip cocaine injection (10 mg/kg, ip) and were allowed to press for contingent cue light presentation. Immediately after reactivation, they were administered an intra-mPFC infusion of vehicle or anisomycin. Two additional control groups received extinction and either no memory reactivation and intra-mPFC infusions as above or intra-mPFC infusions 6 h after memory reactivation. A fourth group received forced abstinence and intra-mPFC infusions immediately after memory reactivation. Combined cocaine + cue-induced reinstatement was given 2-3 days (early) and 8-12 days (late) later. Rats given anisomycin in the Extinction + Reactivation demonstrated decreased reinstatement, while anisomycin treatment did not alter behavior in any of the other three groups. These results suggest that extinction training may recruit the mPFC such that it renders the memory susceptible to disruption by anisomycin. These findings have implications for using extinction training prior to or in conjunction with other therapies, including reconsolidation disruption, to enhance prefrontal control over drug-seeking behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Changes in endocannabinoid and N-acylethanolamine levels in rat brain structures following cocaine self-administration and extinction training.

    Science.gov (United States)

    Bystrowska, Beata; Smaga, Irena; Frankowska, Małgorzata; Filip, Małgorzata

    2014-04-03

    Preclinical investigations have demonstrated that drugs of abuse alter the levels of lipid-based signalling molecules, including endocannabinoids (eCBs) and N-acylethanolamines (NAEs), in the rodent brain. In addition, several drugs targeting eCBs and/or NAEs are implicated in reward and/or seeking behaviours related to the stimulation of dopamine systems in the brain. In our study, the brain levels of eCBs (anandamide (AEA) and 2-arachidonoylglycerol (2-AG)) and NAEs (oleoylethanolamide (OEA) and palmitoylethanolamide (PEA)) were analyzed via an LC-MS/MS method in selected brain structures of rats during cocaine self-administration and after extinction training according to the "yoked" control procedure. Repeated (14days) cocaine (0.5mg/kg/infusion) self-administration and yoked drug delivery resulted in a significant decrease (ca. 52%) in AEA levels in the cerebellum, whereas levels of 2-AG increased in the frontal cortex, the hippocampus and the cerebellum and decreased in the hippocampus and the dorsal striatum. In addition, we detected increases (>150%) in the levels of OEA and PEA in the limbic areas in both cocaine treated groups, as well as an increase in the tissue levels of OEA in the dorsal striatum in only the yoked cocaine group and increases in the tissue levels of PEA in the dorsal striatum (both cocaine groups) and the nucleus accumbens (yoked cocaine group only). Compared to the yoked saline control group, extinction training (10days) resulted in a potent reduction in AEA levels in the frontal cortex, the hippocampus and the nucleus accumbens and in 2-AG levels in the hippocampus, the dorsal striatum and the cerebellum. The decreases in the limbic and subcortical areas were more apparent for rats that self-administered cocaine. Following extinction, there was a region-specific change in the levels of NAEs in rats previously injected with cocaine; a potent increase (ca. 100%) in the levels of OEA and PEA was detected in the prefrontal cortex and the

  17. Intravenous self-administration of mephedrone, methylone and MDMA in female rats.

    Science.gov (United States)

    Creehan, Kevin M; Vandewater, Sophia A; Taffe, Michael A

    2015-05-01

    Male rats will intravenously self-administer (IVSA) the substituted cathinone stimulants ("bath salts") mephedrone (4-methylmethcathione) and methylone (3,4-methylenedioxymethcathinone) robustly, whereas the IVSA of 3,4-methylenedioxymethamphetamine (MDMA) is inconsistent in many rat models. There are no data available on the self-administration of these drugs in female rats, thus a study was undertaken to contrast them directly. Groups of female Wistar rats were trained to self-administer mephedrone, methylone or MDMA (0.5 mg/kg/inf) under a Fixed-Ratio (FR) 1 schedule of reinforcement for 14 sessions. Following the acquisition interval, animals were evaluated in FR (0.0, 0.125, 0.25, 0.5, 1.0, 2.5 mg/kg/inf) and PR (0.125, 1.0 mg/kg/inf) dose-substitution procedures. The results show that female rats acquired the self-administration of all three compounds with intakes in mephedrone-trained rats that were significantly higher than that of methylone-trained or MDMA-trained rats. In dose-substitution under either FR or PR contingencies, however, the potencies of all three drugs were similar within the original training groups. The mephedrone-trained animals exhibited higher intakes of all drugs during dose-substitution, indicating lasting consequences of the training drug. Abuse liability of these three compounds is therefore predicted to be similar in established stimulant users but may differ in liability if they are primary drugs of initiation.

  18. Methylphenidate treatment beyond adolescence maintains increased cocaine self-administration in the Spontaneously Hypertensive Rat model of Attention Deficit/Hyperactivity Disorder

    OpenAIRE

    Baskin, Britahny M.; Linda P. Dwoskin; Kantak, Kathleen M.

    2015-01-01

    Past research with the Spontaneously Hypertensive Rat (SHR) model of Attention Deficit/Hyperactivity Disorder showed that adolescent methylphenidate treatment enhanced cocaine abuse risk in SHR during adulthood. Acquisition of cocaine self-administration was faster, and cocaine dose-response functions were shifted upward under fixed-ratio and progressive ratio schedules compared to adult SHR that received adolescent vehicle treatment or to control strains that received adolescent methylphenid...

  19. Prior Cocaine Self-Administration Increases Response-Outcome Encoding That Is Divorced from Actions Selected in Dorsal Lateral Striatum.

    Science.gov (United States)

    Burton, Amanda C; Bissonette, Gregory B; Zhao, Adam C; Patel, Pooja K; Roesch, Matthew R

    2017-08-09

    Dorsal lateral striatum (DLS) is a highly associative structure that encodes relationships among environmental stimuli, behavioral responses, and predicted outcomes. DLS is known to be disrupted after chronic drug abuse; however, it remains unclear what neural signals in DLS are altered. Current theory suggests that drug use enhances stimulus-response processing at the expense of response-outcome encoding, but this has mostly been tested in simple behavioral tasks. Here, we investigated what neural correlates in DLS are affected by previous cocaine exposure as rats performed a complex reward-guided decision-making task in which predicted reward value was independently manipulated by changing the delay to or size of reward associated with a response direction across a series of trial blocks. After cocaine self-administration, rats exhibited stronger biases toward higher-value reward and firing in DLS more strongly represented action-outcome contingencies independent from actions subsequently taken rather than outcomes predicted by selected actions (chosen-outcome contingencies) and associations between stimuli and actions (stimulus-response contingencies). These results suggest that cocaine self-administration strengthens action-outcome encoding in rats (as opposed to chosen-outcome or stimulus-response encoding), which abnormally biases behavior toward valued reward when there is a choice between two options during reward-guided decision-making.SIGNIFICANCE STATEMENT Current theories suggest that the impaired decision-making observed in individuals who chronically abuse drugs reflects a decrease in goal-directed behaviors and an increase in habitual behaviors governed by neural representations of response-outcome (R-O) and stimulus-response associations, respectively. We examined the impact that prior cocaine self-administration had on firing in dorsal lateral striatum (DLS), a brain area known to be involved in habit formation and affected by drugs of abuse

  20. Methylphenidate enhances the abuse-related behavioral effects of nicotine in rats: intravenous self-administration, drug discrimination, and locomotor cross-sensitization.

    Science.gov (United States)

    Wooters, Thomas E; Neugebauer, Nichole M; Rush, Craig R; Bardo, Michael T

    2008-04-01

    Stimulant drugs, including D-amphetamine, cocaine, and methylphenidate, increase cigarette smoking in controlled human laboratory experiments. Although the mechanism(s) underlying this effect are unknown, it is possible that stimulants may enhance directly the abuse-related effects of nicotine. In the present study, we characterized the behavioral pharmacological interactions between methylphenidate and nicotine in the intravenous self-administration, drug discrimination, and locomotor cross-sensitization procedures. Adult male Sprague-Dawley rats were trained to respond for intravenous nicotine (0.01 or 0.03 mg/kg/infusion) or sucrose, and the acute effects of methylphenidate (1.25-10 mg/kg) were determined; in addition, separate groups of rats were treated with methylphenidate (2.5 mg/kg) or saline before 12 consecutive nicotine (0.03 mg/kg/infusion) self-administration sessions. Next, the discriminative stimulus effects of nicotine (0.03-0.3 mg/kg) and methylphenidate (1.25-10 mg/kg), alone and in combination with a low nicotine dose (0.056 mg/kg), were tested in nicotine-trained rats. Finally, the locomotor effect of repeated methylphenidate (2.5 mg/kg) was tested in rats previously treated with nicotine (0.2-0.8 mg/kg). Results indicated that acute methylphenidate increased the rate of nicotine self-administration at doses that reduced sucrose-maintained responding; furthermore, tolerance to this effect was not apparent following repeated methylphenidate. Methylphenidate, while not substituting for nicotine alone, dose-dependently enhanced the discriminative stimulus effect of a low nicotine dose. In addition, repeated nicotine exposure promoted the development of locomotor sensitization to methylphenidate. Taken together with recent clinical findings, these results suggest that methylphenidate may enhance the abuse-related behavioral effects of nicotine, perhaps increasing vulnerability to tobacco dependence.

  1. Effects of social reorganization on dopamine D2/D3 receptor availability and cocaine self-administration in male cynomolgus monkeys.

    Science.gov (United States)

    Czoty, P W; Gould, R W; Gage, H D; Nader, M A

    2017-06-12

    Studies have demonstrated that brain dopamine D2/D3 receptors (D2/D3R) and the reinforcing effects of cocaine can be influenced by a monkey's position in the social dominance hierarchy. In this study, we manipulated the social ranks of monkeys by reorganizing social groups and assessed effects on D2/D3R availability and cocaine self-administration. Male cynomolgus monkeys (N = 12) had been trained to self-administer cocaine under a concurrent cocaine-food reinforcement schedule. Previously, PET measures of D2/D3R availability in the caudate nucleus and putamen had been obtained with [(18)F]fluoroclebopride during cocaine abstinence, while monkeys lived in stable social groups of four monkeys/pen. For this study, monkeys were reorganized into groups that consisted of (1) four previously dominant, (2) four previously subordinate, and (3) a mix of previously dominant and subordinate monkeys. After 3 months, D2/D3R availability was redetermined and cocaine self-administration was reexamined. D2/D3R availability significantly increased after reorganization in monkeys who were formerly subordinate, with the greatest increases observed in those that became dominant. No consistent changes in D2/D3R availability were observed in formerly dominant monkeys. Cocaine self-administration did not vary according to rank after reorganization of social groups. However, when compared to their previous cocaine self-administration data, the potency of cocaine as a reinforcer decreased in 9 of 11 monkeys. These results indicate that changing the social conditions can alter D2/D3R availability in subordinate monkeys in a manner suggestive of environmental enrichment. In most monkeys, social reorganization shifted the cocaine dose-response curve to the right, also consistent with environmental enrichment.

  2. Continuous intracerebroventricular infusion of the competitive NMDA receptor antagonist, LY235959, facilitates escalation of cocaine self-administration and increases break point for cocaine in Sprague-Dawley rats.

    Science.gov (United States)

    Allen, Richard M; Uban, Kristina A; Atwood, Elizabeth M; Albeck, David S; Yamamoto, Dorothy J

    2007-11-01

    Although escalation of consumption is an important characteristic of cocaine dependence, the neurobiological mechanisms that mediate this phenomenon have not been fully described. In this study, we used male, Sprague-Dawley rats to measure the effects of acute and continuous intracerebroventricular (ICV) administration of the competitive NMDA receptor antagonist, LY235959, on cocaine self-administration behavior under various schedules of reinforcement and access conditions. Single ICV infusions of LY235959 (0.03-0.3 microg/5 microl) produced dose-dependent and statistically significant decreases in the number of cocaine infusions earned under a progressive ratio schedule of reinforcement. In a second experiment, vehicle or LY235959 (0.2-0.3 microg/day) was continuously administered ICV to rats via surgically-implanted subcutaneous osmotic minipump/intracranial cannula assemblies. Both vehicle- and LY235959-treated rats significantly escalated cocaine self-administration over the 10 long access sessions; however, rats treated with LY235959 escalated cocaine self-administration faster and to a greater degree than vehicle-treated rats. There was a statistically significant increase in cocaine infusions earned under the PR schedule in LY235959-treated rats, but not vehicle-treated rats, after 10 long access cocaine self-administration sessions. These data support the hypothesis that escalation of cocaine consumption is mediated by hypo-glutamatergic tone in the central nervous system and this facilitation of escalation is associated with an increase in motivation to respond for cocaine.

  3. A Single Amphetamine Infusion Reverses Deficits in Dopamine Nerve-Terminal Function Caused by a History of Cocaine Self-Administration.

    Science.gov (United States)

    Ferris, Mark J; Calipari, Erin S; Rose, Jamie H; Siciliano, Cody A; Sun, Haiguo; Chen, Rong; Jones, Sara R

    2015-07-01

    There are ∼ 1.6 million people who meet the criteria for cocaine addiction in the United States, and there are currently no FDA-approved pharmacotherapies. Amphetamine-based dopamine-releasing drugs have shown efficacy in reducing the motivation to self-administer cocaine and reducing intake in animals and humans. It is hypothesized that amphetamine acts as a replacement therapy for cocaine through elevation of extracellular dopamine levels. Using voltammetry in brain slices, we tested the ability of a single amphetamine infusion in vivo to modulate dopamine release, uptake kinetics, and cocaine potency in cocaine-naive animals and after a history of cocaine self-administration (1.5 mg/kg/infusion, fixed-ratio 1, 40 injections/day × 5 days). Dopamine kinetics were measured 1 and 24 h after amphetamine infusion (0.56 mg/kg, i.v.). Following cocaine self-administration, dopamine release, maximal rate of uptake (Vmax), and membrane-associated dopamine transporter (DAT) levels were reduced, and the DAT was less sensitive to cocaine. A single amphetamine infusion reduced Vmax and membrane DAT levels in cocaine-naive animals, but fully restored all aspects of dopamine terminal function in cocaine self-administering animals. Here, for the first time, we demonstrate pharmacologically induced, immediate rescue of deficits in dopamine nerve-terminal function in animals with a history of high-dose cocaine self-administration. This observation supports the notion that the DAT expression and function can be modulated on a rapid timescale and also suggests that the pharmacotherapeutic actions of amphetamine for cocaine addiction go beyond that of replacement therapy.

  4. Cocaine Self-Administration Alters the Relative Effectiveness of Multiple Memory Systems during Extinction

    Science.gov (United States)

    Gabriele, Amanda; Setlow, Barry; Packard, Mark G.

    2009-01-01

    Rats were trained to run a straight-alley maze for an oral cocaine or sucrose vehicle solution reward, followed by either response or latent extinction training procedures that engage neuroanatomically dissociable "habit" and "cognitive" memory systems, respectively. In the response extinction condition, rats performed a runway approach response…

  5. Aripiprazole blocks acute self-administration of cocaine and is not self-administered in mice

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Sager, Thomas N; Petersen, Jørgen H

    2008-01-01

    doses (0.03, 0.1, and 0.3 mg/kg/infusion) even caused significant decreases in nose-poking activity, possibly due to extrapyramidal side effects. CONCLUSIONS: These data are consistent with a potential role for aripiprazole in treatment of cocaine addiction without abuse potential per se....

  6. Increased cocaine self-administration in M4 muscarinic acetylcholine receptor knockout mice

    DEFF Research Database (Denmark)

    Schmidt, Lene Sørensen; Thomsen, Morgane; Weikop, Pia

    2011-01-01

    Rationale The reinforcing effects of cocaine are mediated by the mesolimbic dopamine system. Behavioral and neurochemical studies have shown that the cholinergic muscarinic M4 receptor subtype plays an important role in regulation of dopaminergic neurotransmission. Objectives Here we investigated...... of drug addiction...

  7. Self-administration of ethanol, cocaine, or nicotine does not decrease the soma size of ventral tegmental area dopamine neurons.

    Directory of Open Access Journals (Sweden)

    Michelle S Mazei-Robison

    Full Text Available Our previous observations show that chronic opiate administration, including self-administration, decrease the soma size of dopamine (DA neurons in the ventral tegmental area (VTA of rodents and humans, a morphological change correlated with increased firing rate and reward tolerance. Given that a general hallmark of drugs of abuse is to increase activity of the mesolimbic DA circuit, we sought to determine whether additional drug classes produced a similar morphological change. Sections containing VTA were obtained from rats that self-administered cocaine or ethanol and from mice that consumed nicotine. In contrast to opiates, we found no change in VTA DA soma size induced by any of these other drugs. These data suggest that VTA morphological changes are induced in a drug-specific manner and reinforce recent findings that some changes in mesolimbic signaling and neuroplasticity are drug-class dependent.

  8. Cocaine self-administration alters the relative effectiveness of multiple memory systems during extinction

    OpenAIRE

    Gabriele, Amanda; Setlow, Barry; Packard, Mark G.

    2009-01-01

    Rats were trained to run a straight-alley maze for an oral cocaine or sucrose vehicle solution reward, followed by either response or latent extinction training procedures that engage neuroanatomically dissociable “habit” and “cognitive” memory systems, respectively. In the response extinction condition, rats performed a runway approach response to an empty fluid well. In the latent extinction condition, rats were placed at the empty fluid well without performing a runway approach response. R...

  9. Synapse density and dendritic complexity are reduced in the prefrontal cortex following seven days of forced abstinence from cocaine self-administration.

    Science.gov (United States)

    Rasakham, Khampaseuth; Schmidt, Heath D; Kay, Kevin; Huizenga, Megan N; Calcagno, Narghes; Pierce, R Christopher; Spires-Jones, Tara L; Sadri-Vakili, Ghazaleh

    2014-01-01

    Chronic cocaine exposure in both human addicts and in rodent models of addiction reduces prefrontal cortical activity, which subsequently dysregulates reward processing and higher order executive function. The net effect of this impaired gating of behavior is enhanced vulnerability to relapse. Previously we have shown that cocaine-induced increases in brain-derived neurotrophic factor (BDNF) expression in the medial prefrontal cortex (PFC) is a neuroadaptive mechanism that blunts the reinforcing efficacy of cocaine. As BDNF is known to affect neuronal survival and synaptic plasticity, we tested the hypothesis that abstinence from cocaine self-administration would lead to alterations in neuronal morphology and synaptic density in the PFC. Using a novel technique, array tomography and Golgi staining, morphological changes in the rat PFC were analyzed following 14 days of cocaine self-administration and 7 days of forced abstinence. Our results indicate that overall dendritic branching and total synaptic density are significantly reduced in the rat PFC. In contrast, the density of thin dendritic spines are significantly increased on layer V pyramidal neurons of the PFC. These findings indicate that dynamic structural changes occur during cocaine abstinence that may contribute to the observed hypo-activity of the PFC in cocaine-addicted individuals.

  10. Synapse density and dendritic complexity are reduced in the prefrontal cortex following seven days of forced abstinence from cocaine self-administration.

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    Khampaseuth Rasakham

    Full Text Available Chronic cocaine exposure in both human addicts and in rodent models of addiction reduces prefrontal cortical activity, which subsequently dysregulates reward processing and higher order executive function. The net effect of this impaired gating of behavior is enhanced vulnerability to relapse. Previously we have shown that cocaine-induced increases in brain-derived neurotrophic factor (BDNF expression in the medial prefrontal cortex (PFC is a neuroadaptive mechanism that blunts the reinforcing efficacy of cocaine. As BDNF is known to affect neuronal survival and synaptic plasticity, we tested the hypothesis that abstinence from cocaine self-administration would lead to alterations in neuronal morphology and synaptic density in the PFC. Using a novel technique, array tomography and Golgi staining, morphological changes in the rat PFC were analyzed following 14 days of cocaine self-administration and 7 days of forced abstinence. Our results indicate that overall dendritic branching and total synaptic density are significantly reduced in the rat PFC. In contrast, the density of thin dendritic spines are significantly increased on layer V pyramidal neurons of the PFC. These findings indicate that dynamic structural changes occur during cocaine abstinence that may contribute to the observed hypo-activity of the PFC in cocaine-addicted individuals.

  11. Inactivation of the central nucleus of the amygdala reduces the effect of punishment on cocaine self-administration in rats

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    Xue, YueQiang; Steketee, Jeffery D.; Sun, Wenlin

    2012-01-01

    Continued cocaine use despite the negative consequences is a hallmark of cocaine addiction. One such consequence is punishment that is often used by society to curb cocaine use. Unfortunately, we know little about the mechanism involved in regulation by punishment of cocaine use. The fact that cocaine addicts continue cocaine use despite potential severe punishment suggests that the mechanism may be impaired. Such impairment is expected to critically contribute to compulsive cocaine use. This...

  12. Associations of OPRM1 A118G and alcohol sensitivity with intravenous alcohol self-administration in young adults.

    Science.gov (United States)

    Hendershot, Christian S; Claus, Eric D; Ramchandani, Vijay A

    2016-01-01

    Human laboratory and animal models implicate variation in the μ-opioid receptor gene (OPRM1) as relevant for alcohol-related reward. OPRM1 is associated with alcohol self-administration in non-human primate studies, but the relevance of this finding to human models is unclear. This study used computer-assisted self-infusion of ethanol (CASE) to examine associations among OPRM1 A118G genotype, subjective responses to alcohol and intravenous alcohol self-administration in young heavy drinkers (n = 40, mean age = 19.95 years, SD = 0.82). Participants completed a 2-hour CASE session comprising a priming phase followed by ad libitum self-administration in a free-access paradigm. Participants achieved a mean peak breath alcohol concentration (BrAC) of 81.18 mg% (SD = 24.96). Those with the OPRM1 118G variant (GA or GG genotypes) achieved significantly higher peak BrAC (M = 94.90 mg%, SD = 16.56) than those with the AA genotype (M = 74.46 mg%, SD = 25.36), reflecting a significantly greater number of alcohol requests among GA/GG participants. Eighty percent of GA/GG participants surpassed a threshold defining a laboratory analog of heavy alcohol exposure (80 mg%) compared with 46 percent of AA participants. Results indicated significant associations between subjective measures of alcohol sensitivity and CASE outcomes, although the pattern of findings differed across self-report measures. Subjective responses did not differ by OPRM1 status. These results offer further support for the feasibility of the CASE paradigm and provide initial evidence for an association of OPRM1 with alcohol self-administration in a human laboratory context. © 2014 Society for the Study of Addiction.

  13. Effects of oral and intravenous administration of buspirone on food-cocaine choice in socially housed male cynomolgus monkeys.

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    Czoty, Paul W; Nader, Michael A

    2015-03-13

    Drugs acting at D3 dopamine receptors have been suggested as medications for cocaine dependence. These experiments examined the effects of intravenously and orally administered buspirone, a D2-like receptor antagonist with high affinity for D3 and D4 receptors, on the relative reinforcing strength of cocaine in group-housed male cynomolgus monkeys. Use of socially housed monkeys permitted the assessment of whether social status, known to influence D2-like receptor availability, modulates the behavioral effects of buspirone. Buspirone was administered acutely to monkeys self-administering cocaine under a food-drug choice procedure in which a cocaine self-administration dose-effect curve was determined daily. When administered by either route, buspirone significantly decreased cocaine choice in dominant-ranked monkeys. In subordinate monkeys, however, i.v. buspirone was ineffective on average, and oral buspirone increased choice of lower cocaine doses. The effects of buspirone only differed according to route of administration in subordinate monkeys. Moreover, it is noteworthy that the effects of buspirone were similar to those of the D3 receptor-selective antagonist PG01037 and qualitatively different than those of less selective drugs that act at D2-like or serotonin (5-HT)1A receptors, suggesting a D3 and possibly D4 receptor mechanism of action for buspirone. Taken together, the data support the utility of drugs targeting D3/D4 receptors as potential treatments for cocaine addiction, particularly in combination with enriching environmental manipulations.

  14. Methylphenidate treatment beyond adolescence maintains increased cocaine self-administration in the spontaneously hypertensive rat model of attention deficit/hyperactivity disorder.

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    Baskin, Britahny M; Dwoskin, Linda P; Kantak, Kathleen M

    2015-04-01

    Past research with the spontaneously hypertensive rat (SHR) model of attention deficit/hyperactivity disorder showed that adolescent methylphenidate treatment enhanced cocaine abuse risk in SHR during adulthood. The acquisition of cocaine self-administration was faster, and cocaine dose-response functions were shifted upward under fixed-ratio and progressive ratio schedules compared to adult SHR that received adolescent vehicle treatment or to control strains that received adolescent methylphenidate treatment. The current study determined if extending treatment beyond adolescence would ameliorate long-term consequences of adolescent methylphenidate treatment on cocaine abuse risk in adult SHR. Treatments (vehicle or 1.5mg/kg/day oral methylphenidate) began on postnatal day 28. Groups of male SHR were treated with vehicle during adolescence and adulthood, with methylphenidate during adolescence and vehicle during adulthood, or with methylphenidate during adolescence and adulthood. The group receiving adolescent-only methylphenidate was switched to vehicle on P56. Cocaine self-administration began on postnatal day 77, and groups receiving methylphenidate during adolescence and adulthood were treated either 1-h before or 1-h after daily sessions. At baseline under a fixed-ratio 1 schedule, cocaine self-administration (2h sessions; 0.3mg/kg unit dose) did not differ among the four treatment groups. Under a progressive ratio schedule (4.5h maximum session length; 0.01-1.0mg/kg unit doses), breakpoints for self-administered cocaine in SHR receiving the adult methylphenidate treatment 1-h pre-session were not different from the vehicle control group. However, compared to the vehicle control group, breakpoints for self-administered cocaine at the 0.3 and 1.0mg/kg unit doses were greater in adult SHR that received adolescent-only methylphenidate or received methylphenidate that was continued into adulthood and administered 1-h post-session. These findings suggest that

  15. Forced abstinence from cocaine self-administration is associated with DNA methylation changes in myelin genes in the corpus callosum: a preliminary study

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    David Andrew Nielsen

    2012-06-01

    Full Text Available Background: Human cocaine abuse is associated with alterations in white matter integrity revealed upon brain imaging, an observation that is recapitulated in an animal model of continuous cocaine exposure. The mechanism through which cocaine may affect white matter is unknown and the present study tested the hypothesis that cocaine self-administration results in changes in DNA methylation that could result in altered expression of several myelin genes that could contribute to the effects of cocaine on white matter integrity.Methods: In the present study, we examined the impact of forced abstinence from cocaine self-administration on chromatin-associated changes in white matter. To this end, rats were trained to self-administer cocaine (0.75 mg/kg/0.1 ml infusion for 14 days followed by forced abstinence for 1 day (N = 6 or 30 days (N = 6 before sacrifice. Drug-free, sham surgery controls (n = 7 were paired with the experimental groups. Global DNA methylation and DNA methylation at specific CpG sites in the promoter regions of myelin basic protein (Mbp, proteolipid protein-1 (Plp1, and SRY-related HMG-box-10 (Sox10 genes were analyzed in DNA extracted from corpus callosum.Results: Significant differences in the overall methylation patterns of the Sox10 promoter region were observed in the corpus callosum of rats at 30 days of forced abstinence from cocaine self-administration relative to sham controls; the -189, -142, -93 and -62 CpG sites were significantly hypomethylated point-wise at this time point. After correction for multiple comparisons, no differences in global methylation or the methylation patterns of Mbp or Plp1 were found.Conclusions: Forced abstinence from cocaine self-administration was associated with differences in DNA methylation at specific CpG sites in the promoter region of the Sox10 gene in corpus callosum. These changes may be related to reductions in normal age related changes in DNA methylation and could be a factor in

  16. Lesions of cholinergic pedunculopontine tegmental nucleus neurons fail to affect cocaine or heroin self-administration or conditioned place preference in rats.

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    Stephan Steidl

    Full Text Available Cholinergic input to the ventral tegmental area (VTA is known to contribute to reward. Although it is known that the pedunculopontine tegmental nucleus (PPTg provides an important source of excitatory input to the dopamine system, the specific role of PPTg cholinergic input to the VTA in cocaine reward has not been previously determined. We used a diphtheria toxin conjugated to urotensin-II (Dtx::UII, the endogenous ligand for urotensin-II receptors expressed by PPTg cholinergic but not glutamatergic or GABAergic cells, to lesion cholinergic PPTg neurons. Dtx::UII toxin infusion resulted in the loss of 95.78 (±0.65% of PPTg cholinergic cells but did not significantly alter either cocaine or heroin self-administration or the development of cocaine or heroin conditioned place preferences. Thus, cholinergic cells originating in PPTg do not appear to be critical for the rewarding effects of cocaine or of heroin.

  17. Repeated intravenous administrations of teneurin-C terminal associated peptide (TCAP)-1 attenuates reinstatement of cocaine seeking by corticotropin-releasing factor (CRF) in rats.

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    Erb, Suzanne; McPhee, Matthew; Brown, Zenya J; Kupferschmidt, David A; Song, Lifang; Lovejoy, David A

    2014-08-01

    The teneurin c-terminal associated peptides (TCAP) have been implicated in the regulation of the stress response, possibly via a corticotropin-releasing factor (CRF)-related mechanism. We have previously shown that repeated intracerebroventricular (ICV) injections of TCAP-1 attenuate the reinstatement of cocaine seeking by CRF in rats. Here, we determined whether intravenous (IV) administrations of TCAP-1 would likewise attenuate CRF-induced reinstatement, and whether this effect would vary depending on the rat's history of cocaine self administration. Rats were trained to self-administer cocaine for 10 days, during once daily sessions that were either 3h ("short access"; ShA) or 6h ("long access"; LgA). Rats were then given five daily injections of TCAP-1 (0, 300, or 3,000 pmol, IV) in their home cage. Subsequently, they were returned to the self-administration chambers where extinction of cocaine seeking and testing for CRF-induced reinstatement of cocaine seeking was carried out. Repeated IV administrations of TCAP-1 were efficacious in attenuating CRF-induced reinstatement of cocaine seeking, but at different doses in ShA and LgA rats. Taken together, the findings extend previous work showing a consistent effect of repeated ICV TCAP-1 on CRF-induced reinstatement of cocaine seeking, and point to a potential therapeutic benefit of TCAP-1 in attenuating cocaine seeking behaviors.

  18. Menthol facilitates the intravenous self-administration of nicotine in rats

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    Tengfei eWang

    2014-12-01

    Full Text Available Menthol is preferred by approximately 25% of smokers and is the most common flavoring additive in tobacco and electronic cigarettes. Although some clinical studies have suggested that menthol facilitates the initiation of smoking and enhances the dependence on nicotine, many controversies remain. Using licking as the operant behavior, we found that adolescent rats self-administering nicotine (30 μg/kg/infusion, free base, i.v. with contingent oral menthol (60 μl, 0.01% w/v obtained significantly more infusions than rats receiving a vehicle cue or rats self-administering i.v. saline with a menthol cue. Rats yoked to their menthol-nicotine masters emitted significantly fewer licks on the active spouts, indicating that contingent pairing between nicotine and menthol is required for sustained nicotine intake. Rats that self-administered nicotine with a menthol cue also exhibited a long-lasting extinction burst and robust reinstatement behavior, neither of which were observed in rats that self-administered saline with a menthol cue. The cooling sensation of menthol is induced by activating the transient receptor potential M8 (TRPM8 channel. When WS-23, an odorless agonist of the TRPM8 channel, was used as a contingent cue for nicotine, the rats obtained a similar number of nicotine infusions as the rats that were provided a menthol cue and exhibited a strong preference for the active spout. In contrast, highly appetitive taste and odor cues failed to support nicotine self-administration. These data indicated that menthol, likely by inducing a cooling sensation, becomes a potent conditioned reinforcer when it is contingently delivered with nicotine. Together, these results provide a key behavioral mechanism by which menthol promotes the use of tobacco products or electronic cigarettes.

  19. The brain-specific neural zinc finger transcription factor 2b (NZF-2b/7ZFMyt1 suppresses cocaine self-administration in rats

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    Vijay Chandrasekar

    2010-04-01

    Full Text Available Brain-specific neural-zinc-finger transcription factor-2b (NZF2b/7ZFMyt1 is induced in the mesolimbic dopaminergic region after chronic cocaine exposure and lentiviral-mediated expression of NZF2b/7ZFMyt1 in the nucleus accumbens results in decreased locomotor activity (Chandrasekar and Dreyer, 2009. In this study the role of NZF2b/7ZFMyt1 in active cocaine seeking and of its interaction with histone deacetylase on the altered behavior has been observed. Localized expression of NZF2b/7ZFMyt1 in the nucleus accumbens resulted in attenuated cocaine self-administration, whereas silencing this transcription factor with lentiviruses expressing siRNAs increased the animal′s motivation to self-infuse cocaine. Low doses of sodium butyrate, a potent inhibitor of histone deacetylase, were sufficient to reverse the NZF2b/7ZFMyt1-mediated decrease in cocaine self-administration. NZF2b/7ZFMyt1 expression resulted in strong induction of transcription factors REST1 and NAC1 and of the dopamine D2 receptor, with concomitant inhibition of BDNF and its receptor TrkB. We show that NZF2b/7ZFMyt1 colocalizes with histone deacetylase-2 (HDAC2, probably overcoming the suppression of transcriptional activity caused by Lingo1. These findings show that molecular adaptations mediated by NZF2b/7ZFMyt1 expression possibly lead to decreased responsiveness to the reinforcing properties of cocaine and play a prominent role in affecting the behavioral changes induced by the drug.

  20. Estradiol as a mechanism for sex differences in the development of an addicted phenotype following extended access cocaine self-administration.

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    Ramôa, Carolina P; Doyle, Susan E; Naim, Diana W; Lynch, Wendy J

    2013-08-01

    Women progress more rapidly after initial cocaine use to addiction as compared with men. Similarly, female rats appear to require less cocaine exposure before developing an addicted phenotype with evidence implicating estradiol as a potential mechanism. The goals of this study were to determine whether there are sex differences in the magnitude of the addicted phenotype under optimized conditions that induce its development in both males and females and to determine the role of estradiol in this effect. Following acquisition, intact male and intact and ovariectomized (OVX) female rats with and without estradiol replacement were given access to cocaine (1.5 mg/kg per infusion) under either extended access (ExA; discrete trial procedure, 4 trials/h, 24 h/day, 10 days) or short access (ShA) conditions (20 infusions maximum/day, 3 days). Motivation to obtain cocaine (0.5 mg/kg/infusion), as assessed under a progressive-ratio schedule, was then examined following a 2-week abstinence period. Results showed that following ExA self-administration, both males and females developed an addicted phenotype, with 9 of 11 males and 8 of 10 females showing a greater than 15% increase in levels of motivation to obtain cocaine as compared with ShA controls. In contrast, within the OVX groups, responding was enhanced from control levels after ExA self-administration in estradiol-replaced rats only. These results suggest that while females may have an enhanced vulnerability to developing an addicted phenotype, they may be similar to males once addiction has developed. These results also suggest that estradiol is critically involved in the development of an addicted phenotype in females.

  1. Asymmetric generalization and interaction profiles in rhesus monkeys discriminating intravenous cocaine or intravenous heroin from vehicle.

    Science.gov (United States)

    Platt, Donna M; Rowlett, James K; Spealman, Roger D

    2010-03-01

    Many polydrug abusers combine cocaine with heroin in the form of a "speedball." This study investigated the discriminative stimulus (DS) effects of speedballs in rhesus monkeys trained to discriminate either intravenous cocaine or intravenous heroin from vehicle. Initial substitution tests revealed an asymmetry in the generalization profile of dopamine and opioid agonists such that mu agonists partially substituted for cocaine, but direct and indirect dopamine agonists did not substitute for heroin. Subsequent speedball tests in which drug mixtures were administered by coinjecting the component drugs while keeping the dose-ratio constant revealed an additional asymmetry. In cocaine-trained monkeys, coadministration of cocaine and heroin produced leftward shifts in the cocaine dose-response function. Heroin's cocaine-enhancing effects were mimicked by the mu agonists fentanyl and methadone and less consistently by the delta agonist (+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC 80) and reversed by the mu antagonist naltrexone and the delta antagonist naltrindole. In heroin-trained monkeys, coadministration of cocaine and heroin attenuated the DS effects of heroin. Cocaine's heroin-attenuating effects were mimicked by the D1-like agonist 6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine (SKF 81297) and the D2-like agonist R-(-)-propylnorapomorphine and reversed by the D1-like antagonist (6aS-trans)-11-chloro-6,6a,7,8,9,13b-hexahydro-7-methyl-5H- benzo[d] aphtha[2,1-b]azepin-12-ol hydrobromide (SCH 39166) and the D2-like antagonist raclopride. Attenuation of the effects of heroin was accompanied by decreases in response rate. These results suggest that heroin enhances the DS effects of cocaine via mu, and to a lesser extent delta, receptor mechanisms; whereas cocaine-induced inhibition of the DS effects of heroin probably was due at least in part to masking of the heroin DS presumably

  2. Roux-en-Y gastric bypass increases intravenous ethanol self-administration in dietary obese rats.

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    James E Polston

    Full Text Available Roux-en-Y gastric bypass surgery (RYGB is an effective treatment for severe obesity. Clinical studies however have reported susceptibility to increased alcohol use after RYGB, and preclinical studies have shown increased alcohol intake in obese rats after RYGB. This could reflect a direct enhancement of alcohol's rewarding effects in the brain or an indirect effect due to increased alcohol absorption after RGYB. To rule out the contribution that changes in alcohol absorption have on its rewarding effects, here we assessed the effects of RYGB on intravenously (IV administered ethanol (1%. For this purpose, high fat (60% kcal from fat diet-induced obese male Sprague Dawley rats were tested ~2 months after RYGB or sham surgery (SHAM using both fixed and progressive ratio schedules of reinforcement to evaluate if RGYB modified the reinforcing effects of IV ethanol. Compared to SHAM, RYGB rats made significantly more active spout responses to earn IV ethanol during the fixed ratio schedule, and achieved higher breakpoints during the progressive ratio schedule. Although additional studies are needed, our results provide preliminary evidence that RYGB increases the rewarding effects of alcohol independent of its effects on alcohol absorption.

  3. Using the self-administration of apomorphine and cocaine to measure the pharmacodynamic potencies and pharmacokinetics of competitive dopamine receptor antagonists.

    Science.gov (United States)

    Norman, Andrew B; Tabet, Michael R; Norman, Mantana K; Tsibulsky, Vladimir L

    2011-01-15

    Competitive dopamine receptor antagonists accelerate psychomotor stimulant self-administration. According to pharmacological theory of competitive antagonism antagonists raise the equiactive agonist concentration. In the self-administration paradigm this is assumed to be the satiety threshold or C(min). The magnitude of the proportional increase in satiety threshold (agonist concentration ratio) as a function of antagonist dose should reflect the antagonist pharmacodynamic potency. The time course of this effect should reflect the rate of change of antagonist occupancy of receptors and, therefore, antagonist concentration, i.e. pharmacokinetics. Rats self-administered apomorphine or cocaine at a stable rate and were then injected i.v. with one of four competitive D₁-like or D₂-like dopamine receptor antagonists and the session continued. The agonist concentrations at the time of each self-administration (satiety thresholds) were calculated during the session. The antagonists accelerated self-administration of both agonists with a concomitant increase in the calculated satiety thresholds. The maximum agonist concentration ratio was proportional to the dose of antagonist. The time courses of the changes in agonist concentration ratio were independent of the agonist and of the dose of antagonist. Schild analysis of the maximum agonist concentration ratio as a function of the antagonist dose allowed apparent pA₂ (or K(dose)) to be measured. Antagonist K(dose) values should provide a quantitative basis for receptor identification in behavioral pharmacology. The assay system may also measure the pharmacokinetics of antagonist elimination from the brain. Agonist self-administration represents a sensitive in vivo pharmacological assay system that provides information useful for pharmacokinetic/pharmacodynamic modeling of antagonist effects.

  4. Effects of imipramine or GABA(B) receptor ligands on the immobility, swimming and climbing in the forced swim test in rats following discontinuation of cocaine self-administration.

    Science.gov (United States)

    Frankowska, Małgorzata; Gołda, Anna; Wydra, Karolina; Gruca, Piotr; Papp, Mariusz; Filip, Małgorzata

    2010-02-10

    We tested if discontinuation of cocaine self-administration can lead to the development of depressive-like symptoms in the forced swim test expressed as changes in immobility, swimming and climbing behaviors in rats. A "yoked" procedure in which rats were run simultaneously in groups of three, with two rats received the passive injection of cocaine or saline, was employed. Later, we examined whether acute treatment with the classical antidepressant imipramine or GABA(B) receptor ligands could alter the increases in immobility recorded after discontinuation of self-administered cocaine. We found a significant increase (44%) in the immobility time 3 days following discontinuation of cocaine (0.5mg/kg/infusion/2h daily) self-administration for 14 days; such enhancement resembled that observed in rats following the chronic mild stress. Acute administration with imipramine (15 or 30 mg/kg), the GABA(B) receptor agonists baclofen (0.125 mg/kg) and SKF 97541 (0.005 mg/kg), the positive allosteric modulator CGP 7930 (0.3mg/kg) or the antagonist SCH 50911 (0.3mg/kg) counteracted the cocaine discontinuation-induced enhancement in the immobility time. The enhanced immobility time in rats that self-administered cocaine (but not given cocaine passively) may reflect the motivated or cognitive processes of reinforced responding of cocaine and could be a potential driver of the addiction process per se. Moreover, either blockade or stimulation of GABA(B) receptors by their ligands in very low doses attenuated the enhanced immobility time in rats after discontinuation of cocaine self-administration and these findings extend preclinical studies demonstrating the potential involvement of GABA(B) receptor ligands to reduce cocaine craving.

  5. Withdrawal from Cocaine Self-Administration Produces Long-Lasting Deficits in Orbitofrontal-Dependent Reversal Learning in Rats

    Science.gov (United States)

    Calu, Donna J.; Stalnaker, Thomas A.; Franz, Theresa M.; Singh, Teghpal; Shaham, Yavin; Schoenbaum, Geoffrey

    2007-01-01

    Drug addicts make poor decisions. These decision-making deficits have been modeled in addicts and laboratory animals using reversal-learning tasks. However, persistent reversal-learning impairments have been shown in rats and monkeys only after noncontingent cocaine injections. Current thinking holds that to represent the human condition…

  6. High anxiety is a predisposing endophenotype for loss of control over cocaine, but not heroin, self-administration in rats

    DEFF Research Database (Denmark)

    Dilleen, Ruth; Pelloux, Yann; Mar, Adam C

    2012-01-01

    RATIONALE: Although high anxiety is commonly associated with drug addiction, its causal role in this disorder is unclear. OBJECTIVES: In light of strong evidence for dissociable neural mechanisms underlying heroin and cocaine addiction, the present study investigated whether high anxiety predicts...

  7. The glucagon-like peptide 1 (GLP-1) receptor agonist exendin-4 reduces cocaine self-administration in mice

    DEFF Research Database (Denmark)

    Sorensen, Gunnar; Reddy, India A.; Weikop, Pia

    2015-01-01

    implicating central GLP-1 receptors in these responses. The present results demonstrate that the GLP-1 system modulates cocaine's effects on behavior and dopamine homeostasis, indicating that the GLP-1 receptor may be a novel target for the pharmacological treatment of drug addiction....

  8. Acute brain metabolic effects of cocaine in rhesus monkeys with a history of cocaine use.

    Science.gov (United States)

    Henry, Porche' Kirkland; Murnane, Kevin S; Votaw, John R; Howell, Leonard L

    2010-12-01

    Cocaine addiction involves an escalation in drug intake which alters many brain functions. The present study documented cocaine-induced changes in brain metabolic activity as a function of cocaine self-administration history. Experimentally naive rhesus monkeys (N = 6) were given increasing access to cocaine under a fixed-ratio schedule of intravenous (i.v.) drug self-administration. PET imaging with F-18 labeled fluorodeoxyglucose (FDG) was used to measure acute intramuscular (i.m.) cocaine-induced changes in brain metabolism in the cocaine-naïve state, following 60 sessions under limited-access conditions (1 h/day), following 60 sessions under extended-access conditions (4 h/day), and following 4 weeks of drug withdrawal. In the cocaine-naïve state, cocaine-induced increases in brain metabolism were restricted to the prefrontal cortex. As cocaine exposure increased from limited to extended access, metabolic effects expanded throughout the frontal cortex and were induced within the striatum. Conversely, cocaine-induced activation was far less robust following withdrawal. The results highlight a progressive expansion of the metabolic effects of cocaine to include previously unaffected dopamine innervated brain regions as a consequence of cocaine self-administration history. The identification of brain regions progressively influenced by drug exposure may be highly relevant toward efforts to develop treatments for cocaine addiction.

  9. Central and peripheral contributions to dynamic changes in nucleus accumbens glucose induced by intravenous cocaine

    Science.gov (United States)

    Wakabayashi, Ken T.; Kiyatkin, Eugene A.

    2015-01-01

    The pattern of neural, physiological and behavioral effects induced by cocaine is consistent with metabolic neural activation, yet direct attempts to evaluate central metabolic effects of this drug have produced controversial results. Here, we used enzyme-based glucose sensors coupled with high-speed amperometry in freely moving rats to examine how intravenous cocaine at a behaviorally active dose affects extracellular glucose levels in the nucleus accumbens (NAc), a critical structure within the motivation-reinforcement circuit. In drug-naive rats, cocaine induced a bimodal increase in glucose, with the first, ultra-fast phasic rise appearing during the injection (latency 6–8 s; ~50 μM or ~5% of baseline) followed by a larger, more prolonged tonic elevation (~100 μM or 10% of baseline, peak ~15 min). While the rapid, phasic component of the glucose response remained stable following subsequent cocaine injections, the tonic component progressively decreased. Cocaine-methiodide, cocaine's peripherally acting analog, induced an equally rapid and strong initial glucose rise, indicating cocaine's action on peripheral neural substrates as its cause. However, this analog did not induce increases in either locomotion or tonic glucose, suggesting direct central mediation of these cocaine effects. Under systemic pharmacological blockade of dopamine transmission, both phasic and tonic components of the cocaine-induced glucose response were only slightly reduced, suggesting a significant role of non-dopamine mechanisms in cocaine-induced accumbal glucose influx. Hence, intravenous cocaine induces rapid, strong inflow of glucose into NAc extracellular space by involving both peripheral and central, non-dopamine drug actions, thus preventing a possible deficit resulting from enhanced glucose use by brain cells. PMID:25729349

  10. NMDA receptors regulate nicotine-enhanced brain reward function and intravenous nicotine self-administration: role of the ventral tegmental area and central nucleus of the amygdala.

    Science.gov (United States)

    Kenny, Paul J; Chartoff, Elena; Roberto, Marisa; Carlezon, William A; Markou, Athina

    2009-01-01

    Nicotine is considered an important component of tobacco responsible for the smoking habit in humans. Nicotine increases glutamate-mediated transmission throughout brain reward circuitries. This action of nicotine could potentially contribute to its intrinsic rewarding and reward-enhancing properties, which motivate consumption of the drug. Here we show that the competitive N-methyl-D-aspartate (NMDA) receptor antagonist LY235959 (0.5-2.5 mg per kg) abolished nicotine-enhanced brain reward function, reflected in blockade of the lowering of intracranial self-stimulation (ICSS) thresholds usually observed after experimenter-administered (0.25 mg per kg) or intravenously self-administered (0.03 mg per kg per infusion) nicotine injections. The highest LY235959 dose (5 mg per kg) tested reversed the hedonic valence of nicotine from positive to negative, reflected in nicotine-induced elevations of ICSS thresholds. LY235959 doses that reversed nicotine-induced lowering of ICSS thresholds also markedly decreased nicotine self-administration without altering responding for food reinforcement, whereas the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor antagonist NBQX had no effects on nicotine intake. In addition, nicotine self-administration upregulated NMDA receptor subunit expression in the central nucleus of the amygdala (CeA) and ventral tegmental area (VTA), suggesting important interactions between nicotine and the NMDA receptor. Furthermore, nicotine (1 microM) increased NMDA receptor-mediated excitatory postsynaptic currents in rat CeA slices, similar to its previously described effects in the VTA. Finally, infusion of LY235959 (0.1-10 ng per side) into the CeA or VTA decreased nicotine self-administration. Taken together, these data suggest that NMDA receptors, including those in the CeA and VTA, gate the magnitude and valence of the effects of nicotine on brain reward systems, thereby regulating motivation to consume the drug.

  11. Central and peripheral contributions to dynamic changes in nucleus accumbens glucose induced by intravenous cocaine

    Directory of Open Access Journals (Sweden)

    Ken Taro Wakabayashi

    2015-02-01

    Full Text Available The pattern of neural, physiological and behavioral effects induced by cocaine is consistent with metabolic neural activation, yet direct attempts to evaluate central metabolic effects of this drug have produced controversial results. Here, we used enzyme-based glucose sensors coupled with high-speed amperometry in freely moving rats to examine how intravenous cocaine at a behaviorally active dose affects extracellular glucose levels in the nucleus accumbens (NAc, a critical structure within the motivation-reinforcement circuit. In drug-naive rats, cocaine induced a bimodal increase in glucose, with the first, ultra-fast phasic rise appearing during the injection (latency 6-8 s; ~50 µM or ~5% of baseline followed by a larger, more prolonged tonic elevation (~100 µM or 10% of baseline, peak ~15 min. While the rapid, phasic component of the glucose response remained stable following subsequent cocaine injections, the tonic component progressively decreased. Cocaine-methiodide, cocaine’s peripherally acting analog, induced an equally rapid and strong initial glucose rise, indicating cocaine’s action on peripheral neural substrates as its cause. However, this analog did not induce increases in either locomotion or tonic glucose, suggesting direct central mediation of these cocaine effects. Under systemic pharmacological blockade of dopamine transmission, both phasic and tonic components of the cocaine-induced glucose response were only slightly reduced, suggesting a significant role of non-dopamine mechanisms in cocaine-induced accumbal glucose influx. Hence, intravenous cocaine induces rapid, strong inflow of glucose into NAc extracellular space by involving both peripheral and central, non-dopamine drug actions, thus preventing a possible deficit resulting from enhanced glucose use by brain cells.

  12. Baclofen has opposite effects on escalation of cocaine self-administration: increased intake in rats selectively bred for high (HiS) saccharin intake and decreased intake in those selected for low (LoS) saccharin intake.

    Science.gov (United States)

    Holtz, Nathan A; Carroll, Marilyn E

    2011-12-01

    Rats selectively bred for high saccharin intake (HiS) self-administer more cocaine, escalate their cocaine intake during long access, and reinstate cocaine seeking at higher levels than those bred for low saccharin intake (LoS). The present study was conducted to determine if baclofen, an agonist at the GABA(b) receptor, has differential effects on the escalation of i.v. cocaine intake and reinstatement of cocaine-seeking in HiS and LoS rats. HiS and LoS rats self-administered cocaine during a 2-h daily short-access (ShA) phase for 3 days and then long-access (LgA) sessions for 21 days followed by a second ShA phase. One group of HiS and LoS rats received i.p. injections of 2.5 mg/kg baclofen (HiS+B and LoS+B, respectively), and other groups of HiS and LoS rats received saline (HiS+Sal and LoS+Sal) before each daily session. In a second experiment, HiS and LoS rats self-administered i.v. cocaine during 2-h sessions for 14 days followed by a 21-day extinction period. Baclofen (2.5 mg/kg, i.p.) or saline was administered before saline- or cocaine-primed reinstatement sessions. The HiS+B group escalated their cocaine self-administration and had increased cocaine infusions in the post-LgA ShA phase. The LoS+B group self-administered less cocaine throughout the entire LgA period compared to the LoS+Sal or HiS groups. Baclofen attenuated reinstatement of cocaine seeking in both the HiS and LoS rats with no phenotype differences. Thus, baclofen had opposite effects on cocaine intake in HiS and LoS rats during escalation; but similar effects during reinstatement. These results suggest that treatment effects might vary with individual differences (HiS vs. LoS) and the phase of drug-motivated behavior that is modeled. Published by Elsevier Inc.

  13. Intravenous lipid emulsion in wide complex arrhythmia with alternating bundle branch block pattern from cocaine overdose.

    Science.gov (United States)

    Kundu, Ria; Almasri, Hamzeh; Moza, Ankush; Ghose, Abhimanyu; Assaly, Ragheb

    2013-01-01

    We describe the management of a young patient who had experienced a cocaine overdose. The patient presented with altered mental status and seizures and subsequently developed a wide complex arrhythmia with a rare alternating bundle branch block pattern. Intravenous lipid emulsion was administered following initial resuscitation and endotracheal intubation, because conservative methods of treating the persistent cardiac arrhythmias failed.

  14. Effects of buspirone and the dopamine D3 receptor compound PG619 on cocaine and methamphetamine self-administration in rhesus monkeys using a food-drug choice paradigm.

    Science.gov (United States)

    John, William S; Banala, Ashwini K; Newman, Amy H; Nader, Michael A

    2015-04-01

    The dopamine (DA) D2 and D3 receptors have been associated with cocaine abuse. A recent study with the D3 receptor (D3R) partial agonist PG619 found that it attenuated cocaine-induced reinstatement and the D2-like receptor antagonist buspirone has shown positive outcomes in two studies of cocaine abuse in monkeys. However, a recent clinical trial indicated that buspirone did not improve abstinence in treatment-seeking cocaine abusers. The objective of the study was to examine PG619 and buspirone under a food-drug choice paradigm in order to better model the clinical findings. In addition, we extended the characterization of both compounds to include methamphetamine (MA) self-administration (SA). Six adult male rhesus monkeys were trained to respond under a concurrent food (1.0-g pellets) and drug (0.01-0.3 mg/kg/injection cocaine or MA) choice paradigm in which complete SA dose-response curves were determined each session (N = 3/group). Monkeys received 5 days of treatment with either PG619 (0.1-3.0 mg/kg, i.v.) or buspirone (0.01-1.0 mg/kg, i.m.). In a follow-up study, the SA doses were reduced (0.003-0.1 mg/kg/injection) to increase reinforcement frequency and buspirone was retested. PG619 did not affect cocaine or MA choice, while buspirone increased low-dose cocaine choice. Changing the SA doses increased the number of reinforcers received each session, but buspirone did not decrease drug choice. Consistent with clinical findings, these results do not support the use of buspirone for psychostimulant abuse and suggest that food-drug choice paradigms may have greater predictive validity than the use of other schedules of reinforcement.

  15. Self-Administered Cocaine Causes Long-Lasting Increases in Impulsive Choice in a Delay Discounting Task

    OpenAIRE

    Mendez, Ian A.; Nicholas W Simon; Hart, Nigel; Mitchell, Marci R.; Nation, Jack R.; Wellman, Paul J.; Setlow, Barry

    2010-01-01

    Cocaine use is associated with high levels of impulsive choice (preference for immediate over delayed rewards), but it is not clear whether cocaine use causes elevated impulsive choice, or whether elevated impulsive choice is solely a predisposing factor for cocaine use. This study examined the effects of prior cocaine self-administration on rats performing a delay discounting task commonly used to measure impulsive choice. Male Long-Evans rats were implanted with intravenous catheters, and f...

  16. Pattern of intake and drug craving predict the development of cocaine addiction-like behavior in rats.

    Science.gov (United States)

    Belin, David; Balado, Eric; Piazza, Pier Vincenzo; Deroche-Gamonet, Véronique

    2009-05-15

    Clinical observations suggest that cocaine addiction often emerges with new patterns of use. Whether these changes are a cause of addiction or its consequence is unknown. We investigated whether the development of an addiction-like behavior in the rat is associated with the pattern of cocaine intake and with cocaine craving, a major feature of cocaine addiction. To determine whether changes in the pattern of cocaine use and enhanced craving precede or parallel the onset of addiction, we used a rat addiction model that incorporates core features of human addiction. For this purpose, the pattern of inter-infusion intervals (a measure of pattern of cocaine intake), sensitivity to cocaine-induced reinstatement (a measure of cocaine craving), and addiction-like behaviour were assessed over several months of intravenous cocaine self-administration. We found that, even at early stages of cocaine self-administration, both the pattern of cocaine intake and the intensity of drug-induced reinstatement predict the severity of cocaine use, measured after 75 days of self-administration. Our results identify key predictors of cocaine addiction-intensified pattern of drug use and high drug-induced craving-that may help in the identification of subjects at risk for subsequent development of severe cocaine addiction.

  17. A touch screen based Stop Signal Response Task in rhesus monkeys for studying impulsivity associated with chronic cocaine self-administration.

    Science.gov (United States)

    Liu, Shijing; Heitz, Richard P; Bradberry, Charles W

    2009-02-15

    Among a range of cognitive deficits, human cocaine addicts display increased impulsivity and decreased performance monitoring. In order to establish an animal model that can be used to study the underlying neurobiology of these deficits associated with addiction, we have developed a touch screen based Stop Signal Response Task for rhesus monkeys. This task is essentially identical to the clinically used Stop Signal Task employed for diagnostic and research purposes. In this task, impulsivity is reflected in the amount of time needed to inhibit a response after it has been initiated, the Stop Signal Response Time (SSRT). Performance monitoring is reflected by the slowing of response times following Stop trials (Post-Stop Slowing, PSS). Herein we report on the task structure, the staged methods for training animals to perform the task, and a comparison of performance values for control and cocaine experienced animals. Relative to controls, monkeys that had self-administered cocaine, followed by 18 months abstinence, displayed increased impulsivity (increased SSRT values), and decreased performance monitoring (decreased PSS values). Our results are consistent with human data, and thereby establish an ideal animal model for studying the etiology and underlying neurobiology of cocaine-induced impulse control and performance monitoring deficits.

  18. Influence of experimental history on nicotine self-administration in squirrel monkeys.

    Science.gov (United States)

    Desai, Rajeev I; Sullivan, Katherine A; Kohut, Stephen J; Bergman, Jack

    2016-06-01

    Methods for establishing robust long-term self-administration of intravenous (i.v.) nicotine, the primary psychoactive agent in tobacco, are not well-established in laboratory animals. Here, we examine the use of a fading procedure to establish robust and consistent i.v. nicotine self-administration under second-order schedule conditions in squirrel monkeys. First, self-administration behavior was developed in two groups of male squirrel monkeys using a second-order fixed-interval 5-min schedule with fixed-ratio 5 units (FI 5-min (FR5: S)). Comparable performances were maintained by i.v. cocaine (0.032 mg/kg/injection (inj); group A, n = 3) and the combination of food delivery (20-30 % condensed milk) and 0.01 mg/kg/inj i.v. nicotine (group B, n = 3). Subsequently, the concentration of condensed milk was gradually reduced to zero in the second group and self-administration behavior was maintained by i.v. nicotine alone. Next, self-administration of a range of doses of i.v. nicotine (0.001-0.032 mg/kg/inj) and, in additional experiments, the minor tobacco alkaloid anatabine (0.01-0.18 mg/kg/inj) was studied in both groups. Results show that nicotine and anatabine had reinforcing effects in both groups. However, optimal doses of nicotine and anatabine maintained significantly higher rates of i.v. self-administration behavior in subjects trained with the fading procedure than in subjects provided with a history of cocaine-maintained responding. These results illustrate conditions under which robust i.v. nicotine self-administration can be established in squirrel monkeys and the influence of prior experimental history in the expression of reinforcing effects of nicotine and anatabine.

  19. Reinforcement-related regulation of AMPA glutamate receptor subunits in the ventral tegmental area enhances motivation for cocaine.

    Science.gov (United States)

    Choi, Kwang Ho; Edwards, Scott; Graham, Danielle L; Larson, Erin B; Whisler, Kimberly N; Simmons, Diana; Friedman, Allyson K; Walsh, Jessica J; Rahman, Zia; Monteggia, Lisa M; Eisch, Amelia J; Neve, Rachael L; Nestler, Eric J; Han, Ming-Hu; Self, David W

    2011-05-25

    Chronic cocaine use produces numerous biological changes in brain, but relatively few are functionally associated with cocaine reinforcement. Here we show that daily intravenous cocaine self-administration, but not passive cocaine administration, induces dynamic upregulation of the AMPA glutamate receptor subunits GluR1 and GluR2 in the ventral tegmental area (VTA) of rats. Increases in GluR1 protein and GluR1(S845) phosphorylation are associated with increased GluR1 mRNA in self-administering animals, whereas increased GluR2 protein levels occurred despite substantial decreases in GluR2 mRNA. We investigated the functional significance of GluR1 upregulation in the VTA on cocaine self-administration using localized viral-mediated gene transfer. Overexpression of GluR1(WT) in rat VTA primarily infected dopamine neurons (75%) and increased AMPA receptor-mediated membrane rectification in these neurons with AMPA application. Similar GluR1(WT) overexpression potentiated locomotor responses to intra-VTA AMPA, but not NMDA, infusions. In cocaine self-administering animals, overexpression of GluR1(WT) in the VTA markedly increased the motivation for cocaine injections on a progressive ratio schedule of cocaine reinforcement. In contrast, overexpression of protein kinase A-resistant GluR1(S845A) in the VTA reduced peak rates of cocaine self-administration on a fixed ratio reinforcement schedule. Neither viral vector altered sucrose self-administration, and overexpression of GluR1(WT) or GluR1(S845A) in the adjacent substantia nigra had no effect on cocaine self-administration. Together, these results suggest that dynamic regulation of AMPA receptors in the VTA during cocaine self-administration contributes to cocaine addiction by acting to facilitate subsequent cocaine use.

  20. Peer influences on drug self-administration: an econometric analysis in socially housed rats.

    Science.gov (United States)

    Peitz, Geoffrey W; Strickland, Justin C; Pitts, Elizabeth G; Foley, Mark; Tonidandel, Scott; Smith, Mark A

    2013-04-01

    Social-learning theories of substance use propose that members of peer groups influence the drug use of other members by selectively modeling, reinforcing, and punishing either abstinence-related or drug-related behaviors. The objective of the present study was to examine the social influences on cocaine self-administration in isolated and socially housed rats, under conditions where the socially housed rats were tested simultaneously with their partner in the same chamber. To this end, male rats were obtained at weaning and housed in isolated or pair-housed conditions for 6 weeks. Rats were then implanted with intravenous catheters and cocaine self-administration was examined in custom-built operant conditioning chambers that allowed two rats to be tested simultaneously. For some socially housed subjects, both rats had simultaneous access to cocaine; for others, only one rat of the pair had access to cocaine. An econometric analysis was applied to the data, and the reinforcing strength of cocaine was measured by examining consumption (i.e. quantity demanded) and elasticity of demand as a function of price, which was manipulated by varying the dose and ratio requirements on a fixed ratio schedule of reinforcement. Cocaine consumption decreased as a function of price in all groups. Elasticity of demand did not vary across groups, but consumption was significantly lower in socially housed rats paired with a rat without access to cocaine. These data suggest that the presence of an abstaining peer decreases the reinforcing strength of cocaine, thus supporting the development of social interventions in drug abuse prevention and treatment programs.

  1. Effects of L-methamphetamine treatment on cocaine- and food-maintained behavior in rhesus monkeys.

    Science.gov (United States)

    Kohut, Stephen J; Bergman, Jack; Blough, Bruce E

    2016-03-01

    Monoamine releasers with prominent dopaminergic actions, e.g., D-methamphetamine (D-MA), significantly reduce cocaine use and craving in clinical and preclinical laboratory studies. However, D-MA and related drugs also display high abuse potential, which limits their acceptability as agonist replacement medications for the management of Cocaine Use Disorder. The L-isomer of methamphetamine (L-MA), unlike D-MA, has preferential noradrenergic actions and is used medicinally with low, if any, abuse liability. The present study was conducted to determine whether L-MA could serve as an agonist replacement medication by both mimicking interoceptive effects of cocaine and decreasing intravenous (IV) cocaine self-administration. Separate groups (N = 4-5) of rhesus monkeys were studied to determine whether L-MA could (1) substitute for cocaine in subjects that discriminated intramuscular (IM) cocaine (0.4 mg/kg) from saline and (2) decrease IV cocaine self-administration under a second-order FR2(VR16:S) schedule of reinforcement. L-MA, like D-MA but with approximately 5-fold lesser potency, substituted for cocaine in drug discrimination experiments in a dose-dependent manner. In IV self-administration studies, 5-10-day treatments with continuously infused L-MA (0.032-0.32 mg/kg/h, IV) dose-dependently decreased cocaine-maintained responding; the highest dosage reduced cocaine intake to levels of saline self-administration without appreciable effects on food-maintained responding. These results indicate that L-MA both shares discriminative stimulus effects with cocaine and reduces cocaine self-administration in a behaviorally selective manner. L-MA and other compounds with a similar pharmacological profile deserve further evaluation for the management of Cocaine Use Disorder.

  2. Cocaine

    Science.gov (United States)

    Cocaine is a white powder. It can be snorted up the nose or mixed with water and injected with a needle. Cocaine can also be made into small white rocks, ... Crack is smoked in a small glass pipe. Cocaine speeds up your whole body. You may feel ...

  3. Cocaine

    Science.gov (United States)

    ... nerves, including seizures and strokes. How can a cocaine overdose be treated? Because cocaine overdose often leads to a heart attack, stroke, or ... severe paranoia with auditory hallucinations A person can overdose on cocaine, which can lead to death. Behavioral therapy may ...

  4. Multifocal multi-organ ischaemia and infarction in a preterm baby due to maternal intravenous cocaine use: a case report

    Directory of Open Access Journals (Sweden)

    Reynolds Ben C

    2009-09-01

    Full Text Available Abstract Introduction Although the adverse effects of cocaine use in pregnancy are well recognised, we believe this case highlights the importance of considering the route of administration, and suggests the possibility of multifocal damage relating to intravenous use. Case presentation A Caucasian female baby of 29-weeks' gestation was spontaneously delivered and subsequently developed multi-organ failure considered unrelated to simple prematurity. Intensive care was re-orientated following the development of massive intraventricular haemorrhage. Conclusion This case illustrates the need for regular cranial ultrasound in babies of pregnancies at risk due to intravenous cocaine use and also the necessity of counselling women who misuse cocaine in the antenatal period. As such, this article will be of most interest to paediatric and obstetric staff.

  5. Effects of acute and chronic aripiprazole treatment on choice between cocaine self-administration and food under a concurrent schedule of reinforcement in rats

    DEFF Research Database (Denmark)

    Thomsen, Morgane; Fink-Jensen, Anders; Woldbye, David

    2008-01-01

    RATIONALE: Dopamine D2-like partial agonists such as aripiprazole have received some attention as potential pharmacotherapies for the treatment of psychostimulant addiction. However, the preclinical evaluations so far have focused on acute effects of aripiprazole. OBJECTIVES: We tested the hypoth......RATIONALE: Dopamine D2-like partial agonists such as aripiprazole have received some attention as potential pharmacotherapies for the treatment of psychostimulant addiction. However, the preclinical evaluations so far have focused on acute effects of aripiprazole. OBJECTIVES: We tested......, chronic treatment with aripiprazole does not show much promise as a potential pharmacotherapy for cocaine addiction. Both acute and chronic treatment data are in agreement with published clinical findings, suggesting that the concurrent choice procedure in rats has predictive validity of efficacy...

  6. HIV Risk in Intravenous Drug Users and Crack Cocaine Smokers: Predicting Stage of Change for Condom Use.

    Science.gov (United States)

    Bowen, Anne M.; Trotter, Robert, II

    1995-01-01

    Expanded the applicability of stage models to the reduction of HIV-risk behaviors. Distributed not-in-treatment crack cocaine smokers and intravenous drug users across three levels of intention to change, which revealed that benefits of change and condom assertiveness varied across the stages of change. Discusses other findings. (RJM)

  7. Hypocretin-1 receptors regulate the reinforcing and reward-enhancing effects of cocaine: Pharmacological and behavioral genetics evidence

    Directory of Open Access Journals (Sweden)

    Jonathan eHollander

    2012-07-01

    Full Text Available Considerable evidence suggests that transmission at hypocretin-1 (orexin-1 receptors (Hcrt-R1 plays an important role in the reinstatement of extinguished cocaine-seeking behaviors in rodents. However, far less is known about the role for hypocretin transmission in regulating ongoing cocaine-taking behavior. Here, we investigated the effects of the selective Hcrt-R1 antagonist SB-334867 on cocaine intake, as measured by intravenous (IV cocaine self-administration in rats. The stimulatory effects of cocaine on brain reward systems contribute to the establishment and maintenance of cocaine-taking behaviors. Therefore, we also assessed the effects of SB-334867 on the reward-enhancing properties of cocaine, as measured by cocaine-induced lowering of intracranial self-stimulation (ICSS thresholds. Finally, to definitively establish a role for Hcrt-R1 in regulating cocaine intake, we assessed IV cocaine self-administration in Hcrt-R1 knockout mice. We found that SB-334867 (1-4 mg/kg dose-dependently decreased cocaine (0.5 mg/kg/infusion self-administration in rats but did not alter responding for food rewards under the same schedule of reinforcement. This suggests that SB-334867 decreased cocaine reinforcement without negatively impacting operant performance. SB-334867 (1-4 mg/kg also dose-dependently attenuated the stimulatory effects of cocaine (10 mg/kg on brain reward systems, as measured by reversal of cocaine-induced lowering of ICSS thresholds in rats. Finally, we found that Hcrt-R1 knockout mice self-administered far less cocaine than wildtype mice across the entire dose-response function. These data demonstrate that Hcrt-R1 play an important role in regulating the reinforcing and reward-enhancing properties of cocaine, and suggest that hypocretin transmission is likely essential for establishing and maintaining the cocaine habit in human addicts.

  8. Usefulness of intravenous lipid emulsion for cardiac toxicity from cocaine overdose.

    Science.gov (United States)

    Arora, Natasha Purai; Berk, William Allen; Aaron, Cynthia Kurke; Williams, Kim Allan

    2013-02-01

    The investigators describe the clinical course of a 26-year-old-man who was brought to the emergency department in a comatose state with status epilepticus after smoking a large amount of crack cocaine. In the emergency department, he was intubated because of depressed mental status and respiratory acidosis. His troponin I remained negative, and electrocardiography showed wide-complex tachycardia with a prolonged corrected QT interval. Because of the corrected QT interval prolongation and wide-complex tachycardia, the patient was started on intravenous magnesium sulfate and sodium bicarbonate. Despite these interventions, no improvement in cardiac rhythm was observed, and electrocardiography continued to show wide-complex tachycardia. The patient became more unstable from a cardiovascular standpoint, with a decrease in blood pressure to 85/60 mm Hg. He was then given 100 ml of 20% lipid emulsion (Intralipid). Within 10 minutes of starting the infusion of 20% lipid emulsion, wide-complex tachycardia disappeared, with an improvement in systemic blood pressure to 120/70 mm Hg. Repeat electrocardiography after the infusion of intravenous lipid emulsion showed regular sinus rhythm with normal QRS and corrected QT intervals. The patient was successfully extubated on day 8 of hospitalization and discharged home on day 10. His cardiac rhythm and blood pressure remained stable throughout his further stay in the hospital. Copyright © 2013. Published by Elsevier Inc.

  9. PRESYNAPTIC DOPAMINE MODULATION BY STIMULANT SELF ADMINISTRATION

    Science.gov (United States)

    España, Rodrigo A.; Jones, Sara R.

    2013-01-01

    The mesolimbic dopamine system is an essential participant in the initiation and modulation of various forms of goal-directed behavior, including drug reinforcement and addiction processes. Dopamine neurotransmission is increased by acute administration of all drugs of abuse, including the stimulants cocaine and amphetamine. Chronic exposure to these drugs via voluntary self-administration provides a model of stimulant abuse that is useful in evaluating potential behavioral and neurochemical adaptations that occur during addiction. This review describes commonly used methodologies to measure dopamine and baseline parameters of presynaptic dopamine regulation, including exocytotic release and reuptake through the dopamine transporter in the nucleus accumbens core, as well as dramatic adaptations in dopamine neurotransmission and drug sensitivity that occur with acute non-contingent and chronic, contingent self-administration of cocaine and amphetamine. PMID:23277050

  10. Dopamine D4 receptor (D4R) deletion in mice does not affect operant responding for food or cocaine

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, P.K.

    2009-10-22

    In this study we examined the genetic contribution of the D4R in food and cocaine self-administration using D4R mice. Mice were examined for operant responding to food pellets or intravenous cocaine. Compared to wild-type mice (D4R{sup +/+}), both heterozygous (D4R{sup +/-}) and knockout (D4R{sup -/-}) mice showed no difference in responding for food or cocaine. Our findings suggest that the D4R is not directly involved in mediating operant response behaviors for food or cocaine.

  11. Acetylcholine release in the mesocorticolimbic dopamine system during cocaine seeking: conditioned and unconditioned contributions to reward and motivation.

    Science.gov (United States)

    You, Zhi-Bing; Wang, Bin; Zitzman, Dawnya; Wise, Roy A

    2008-09-03

    Microdialysis was used to assess the contribution to cocaine seeking of cholinergic input to the mesocorticolimbic dopamine system in ventral tegmental area (VTA). VTA acetylcholine (ACh) was elevated in animals lever pressing for intravenous cocaine and in cocaine-experienced and cocaine-naive animals passively receiving similar "yoked" injections. In cocaine-trained animals, the elevations comprised an initial (first hour) peak to approximately 160% of baseline and a subsequent plateau of 140% of baseline for the rest of the cocaine intake period. In cocaine-naive animals, yoked cocaine injections raised ACh levels to the 140% plateau but did not cause the initial 160% peak. In cocaine-trained animals that received unexpected saline (extinction conditions) rather than the expected cocaine, the initial peak was seen but the subsequent plateau was absent. VTA ACh levels played a causal role and were not just a correlate of cocaine seeking. Blocking muscarinic input to the VTA increased cocaine intake; the increase in intake offset the decrease in cholinergic input, resulting in the same VTA dopamine levels as were seen in the absence of the ACh antagonists. Increased VTA ACh levels (resulting from 10 microM VTA neostigmine infusion) increased VTA dopamine levels and reinstated cocaine seeking in cocaine-trained animals that had undergone extinction; these effects were strongly attenuated by local infusion of a muscarinic antagonist and weakly attenuated by a nicotinic antagonist. These findings identify two cholinergic responses to cocaine self-administration, an unconditioned response to cocaine itself and a conditioned response triggered by cocaine-predictive cues, and confirm that these cholinergic responses contribute to the control of cocaine seeking.

  12. A Thermally Stable Form of Bacterial Cocaine Esterase: A Potential Therapeutic Agent for Treatment of Cocaine Abuse

    Energy Technology Data Exchange (ETDEWEB)

    Brim, Remy L.; Nance, Mark R.; Youngstrom, Daniel W.; Narasimhan, Diwahar; Zhan, Chang-Guo; Tesmer, John J.G.; Sunahara, Roger K.; Woods, James H. (Michigan); (Michigan-Med); (Kentucky)

    2010-09-03

    Rhodococcal cocaine esterase (CocE) is an attractive potential treatment for both cocaine overdose and cocaine addiction. CocE directly degrades cocaine into inactive products, whereas traditional small-molecule approaches require blockade of the inhibitory action of cocaine on a diverse array of monoamine transporters and ion channels. The usefulness of wild-type (wt) cocaine esterase is hampered by its inactivation at 37 C. Herein, we characterize the most thermostable form of this enzyme to date, CocE-L169K/G173Q. In vitro kinetic analyses reveal that CocE-L169K/G173Q displays a half-life of 2.9 days at 37 C, which represents a 340-fold improvement over wt and is 15-fold greater than previously reported mutants. Crystallographic analyses of CocE-L169K/G173Q, determined at 1.6-{angstrom} resolution, suggest that stabilization involves enhanced domain-domain interactions involving van der Waals interactions and hydrogen bonding. In vivo rodent studies reveal that intravenous pretreatment with CocE-L169K/G173Q in mice provides protection from cocaine-induced lethality for longer time periods before cocaine administration than wt CocE. Furthermore, intravenous administration (pretreatment) of CocE-L169K/G173Q prevents self-administration of cocaine in a time-dependent manner. Termination of the in vivo effects of CoCE seems to be dependent on, but not proportional to, its clearance from plasma as its half-life is approximately 2.3 h and similar to that of wt CocE (2.2 h). Taken together these data suggest that CocE-L169K/G173Q possesses many of the properties of a biological therapeutic for treating cocaine abuse but requires additional development to improve its serum half-life.

  13. Optogenetic Central Amygdala Stimulation Intensifies and Narrows Motivation for Cocaine.

    Science.gov (United States)

    Warlow, Shelley M; Robinson, Mike J F; Berridge, Kent C

    2017-08-30

    Addiction is often characterized by intense motivation for a drug, which may be narrowly focused at the expense of other rewards. Here, we examined the role of amygdala-related circuitry in the amplification and narrowing of motivation focus for intravenous cocaine. We paired optogenetic channelrhodopsin (ChR2) stimulation in either central nucleus of amygdala (CeA) or basolateral amygdala (BLA) of female rats with one particular nose-poke porthole option for earning cocaine infusions (0.3 mg/kg, i.v.). A second alternative porthole earned identical cocaine but without ChR2 stimulation. Consequently, CeA rats quickly came to pursue their CeA ChR2-paired cocaine option intensely and exclusively, elevating cocaine intake while ignoring their alternative cocaine alone option. By comparison, BLA ChR2 pairing failed to enhance cocaine motivation. CeA rats also emitted consummatory bites toward their laser-paired porthole, suggesting that higher incentive salience made that cue more attractive. A separate progressive ratio test of incentive motivation confirmed that CeA ChR2 amplified rats' motivation, raising their breakpoint effort price for cocaine by 10-fold. However, CeA ChR2 laser on its own lacked any reinforcement value: laser by itself was never self-stimulated, not even by the same rats in which it amplified motivation for cocaine. Conversely, CeA inhibition by muscimol/baclofen microinjections prevented acquisition of cocaine self-administration and laser preference, whereas CeA inhibition by optogenetic halorhodopsin suppressed cocaine intake, indicating that CeA circuitry is needed for ordinary cocaine motivation. We conclude that CeA ChR2 excitation paired with a cocaine option specifically focuses and amplifies motivation to produce intense pursuit and consumption focused on that single target.SIGNIFICANCE STATEMENT In addiction, intense incentive motivation often becomes narrowly focused on a particular drug of abuse. Here we show that pairing central

  14. Persistent palatable food preference in rats with a history of limited and extended access to methamphetamine self-administration.

    Science.gov (United States)

    Caprioli, Daniele; Zeric, Tamara; Thorndike, Eric B; Venniro, Marco

    2015-09-01

    Recent studies have shown that when given a mutually exclusive choice between cocaine and palatable foods, most rats prefer the non-drug rewards over cocaine. Here, we used a discrete choice procedure to assess whether palatable food preference generalizes to rats with a history of limited (3 hours/day) or extended (6 or 9 hours/day) access to methamphetamine self-administration. On different daily sessions, we trained rats to lever-press for either methamphetamine (0.1-0.2 mg/kg/infusion) or palatable food (five pellets per reward delivery) for several weeks; regular food was freely available. We then assessed food-methamphetamine preference either during training, after priming methamphetamine injections (0.5-1.0 mg/kg), following a satiety manipulation (palatable food exposure in the home cage) or after 21 days of withdrawal from methamphetamine. We also assessed progressive ratio responding for palatable food and methamphetamine. We found that independent of the daily drug access conditions and the withdrawal period, the rats strongly preferred the palatable food over methamphetamine, even when they were given free access to the palatable food in the home cage. Intake of methamphetamine and progressive ratio responding for the drug, both of which increased or escalated over time, did not predict preference in the discrete choice test. Results demonstrate that most rats strongly prefer palatable food pellets over intravenous methamphetamine, confirming previous studies using discrete choice procedures with intravenous cocaine. Results also demonstrate that escalation of drug self-administration, a popular model of compulsive drug use, is not associated with a cardinal feature of human addiction of reduced behavioral responding for non-drug rewards.

  15. Differential characteristics of ketamine self-administration in the olfactory bulbectomy model of depression in male rats.

    Science.gov (United States)

    Babinska, Zuzana; Ruda-Kucerova, Jana

    2017-04-01

    Ketamine has been extensively studied for its antidepressant potential, with promising results in both preclinical and clinical studies. However, concerns regarding its abuse liabilities greatly limit its potential to become an approved treatment for depression. Therefore, a better understanding the risks and benefits of ketamine use in depression is needed. This study aimed to assess the characteristics of operant intravenous (IV) ketamine self-administration and relapse-like behavior in the olfactory bulbectomy (OBX) model of depression in male rats. Twenty-five male Wistar rats were divided randomly into 2 groups; in 1 group the bilateral olfactory bulbectomy was performed, whereas the other group was sham-operated. Intravenous self-administration of ketamine (.5 mg/kg/infusion) was conducted under a fixed ratio 1 schedule of reinforcement. After reaching stable drug intakes, rats then underwent a 14-day period of forced abstinence followed by a drug-free relapse-like session. The forced swim test was conducted before the commencement of the self-administration protocol and on the 1st day of abstinence. Consistent with findings in previous studies on other substances, OBX animals showed increased operant IV ketamine self-administration. In contrast, ketamine-seeking behavior in the OBX group did not differ from sham-operated animals during the relapse-like session, whereas previous studies on other psychostimulants like methamphetamine and cocaine reported increases. Our findings suggest substantially different underlying neuroadaptations between chronic ketamine and psychostimulant exposure. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. The effects of cannabinoid CB1, CB2 and vanilloid TRPV1 receptor antagonists on cocaine addictive behavior in rats.

    Science.gov (United States)

    Adamczyk, Przemysław; Miszkiel, Joanna; McCreary, Andrew C; Filip, Małgorzata; Papp, Mariusz; Przegaliński, Edmund

    2012-03-20

    There is evidence that indicates that tonic activation of cannabinoid CB1 receptors plays a role in extinction/reinstatement of cocaine seeking-behavior but is not involved in the maintenance of cocaine self-administration. To further explore the importance of other endocannabinoid-related receptors in an animal model of cocaine addiction, the present paper examines cannabinoid CB2 receptor antagonist N-((1S)-endo-1,3,3-trimethylbicyclo(2.2.1)heptan-2-yl)-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528) and the transient receptor potential vanilloid type-1 (TRPV1) receptor antagonist N-(3-methoxyphenyl)-4-chlorocinnamide (SB366791) on intravenous (i.v.) cocaine self-administration and extinction/reinstatement of cocaine-seeking behavior in rats. For comparison and reference purposes, the effect of the cannabinoid CB1 receptor antagonist N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251) was also examined. Moreover, for comparison effects of those drugs on operant lever responding for artificial (cocaine) vs. natural (food) reward, food self-administration was also evaluated. Our findings show that AM251 (1-3mg/kg), SR144528 (0.1-1mg/kg) and SB366791 (0.3-1mg/kg) did not affect cocaine self-administration. However, AM251 (0.1-1mg/kg), SR144528 (0.1-1mg/kg) and SB366791 (0.1-1mg/kg) decreased cocaine-induced reinstatement of cocaine-seeking behavior, and AM251 (0.3-1mg/kg) decreased cue-induced reinstatement. Moreover, AM251 (3mg/kg), SR144528 (0.1-1mg/kg) and SB366791 (0.1-1mg/kg) slightly decreased food self-administration behavior, but only AM251 (3mg/kg) reduced food reward. In conclusion, our results indicate for the first time, that tonic activation of CB2 or TRPV1 receptors is involved in cocaine-induced reinstatement of cocaine-seeking behavior, but their activity is not necessary for the rewarding effect of this psychostimulant. In contrast to CB1 receptors, neither CB2 nor

  17. Role for the mesocortical dopamine system in the motivating effects of cocaine.

    Science.gov (United States)

    Koob, G F; Caine, B; Markou, A; Pulvirenti, L; Weiss, F

    1994-01-01

    The search for a neurobiological substrate for the stimulant and reinforcing properties of cocaine has focused for some time on a particular part of the forebrain, the mesocorticolimbic dopamine (DA) system. This mesocorticolimbic DA system innervates the region of the nucleus accumbens (NACC) (ventral striatum) in the anterior part of the basal forebrain and appears to play a critical role in mediating the acute reinforcing effects of cocaine and amphetamine. This chapter reviews the role of mesocorticolimbic DA in the reinforcing properties of psychomotor stimulants as measured by intravenous (IV) drug self-administration in rats. In addition, the primary neuropharmacological mechanism for cocaine reinforcement provides a rich substrate for studying nondopaminergic modulation of the reinforcing actions of cocaine.

  18. Rats markedly escalate their intake and show a persistent susceptibility to reinstatement only when cocaine is injected rapidly.

    Science.gov (United States)

    Wakabayashi, Ken T; Weiss, Mark J; Pickup, Kristen N; Robinson, Terry E

    2010-08-25

    When drugs enter the brain rapidly, liability for addiction is increased, but why this is the case is not well understood. Here we examined the influence of varying the speed of intravenous cocaine delivery on self-administration behavior in rats given limited or extended opportunity to take drug. The speed of cocaine delivery had no effect on self-administration behavior when rats were given only 1 h each day to take cocaine. When given sixfold more time to take cocaine, rats that received cocaine rapidly (5-45 s) increased their total intake eightfold. However, rats that received cocaine more slowly (>90 s) did not avail themselves of the opportunity to take much more drug: they increased their intake only twofold. Furthermore, when tested 45 d after the last self-administration session, a drug-priming injection reinstated drug-seeking behavior only in rats that in the past had cocaine injected rapidly (5 s), and this was associated with a persistent suppression in the ability of cocaine to induce immediate early gene expression. Cocaine may be potentially more addictive when it reaches the brain rapidly because (1) this promotes a marked escalation in intake and (2) it renders individuals more susceptible to relapse long after the discontinuation of drug use. This is presumably because the rapid uptake of drug to the brain preferentially promotes persistent changes in brain systems that regulate motivation for drug, and continuing exposure to large amounts of drug produces a vicious cycle of additional maladaptive changes in brain and behavior.

  19. Attenuated behavioural responses to acute and chronic cocaine in GASP-1-deficient mice.

    Science.gov (United States)

    Boeuf, Julien; Trigo, José Manuel; Moreau, Pierre-Henri; Lecourtier, Lucas; Vogel, Elise; Cassel, Jean-Cristophe; Mathis, Chantal; Klosen, Paul; Maldonado, Rafael; Simonin, Frédéric

    2009-09-01

    G protein-coupled receptor (GPCR) associated sorting protein 1 (GASP-1) interacts with GPCRs and is implicated in their postendocytic sorting. Recently, GASP-1 has been shown to regulate dopamine (D(2)) and cannabinoid (CB1) receptor signalling, suggesting that preventing GASP-1 interaction with GPCRs might provide a means to limit the decrease in receptor signalling upon sustained agonist treatment. In order to test this hypothesis, we have generated and behaviourally characterized GASP-1 knockout (KO) mice and have examined the consequences of the absence of GASP-1 on chronic cocaine treatments. GASP-1 KO and wild-type (WT) mice were tested for sensitization to the locomotor effects of cocaine. Additional mice were trained to acquire intravenous self-administration of cocaine on a fixed ratio 1 schedule of reinforcement, and the motivational value of cocaine was then assessed using a progressive ratio schedule of reinforcement. The dopamine and muscarinic receptor densities were quantitatively evaluated in the striatum of WT and KO mice tested for sensitization and self-administration. Acute and sensitized cocaine-locomotor effects were attenuated in KO mice. A decrease in the percentage of animals that acquired cocaine self-administration was also observed in GASP-1-deficient mice, which was associated with pronounced down-regulation of dopamine and muscarinic receptors in the striatum. These data indicate that GASP-1 participates in acute and chronic behavioural responses induced by cocaine and are in agreement with a role of GASP-1 in postendocytic sorting of GPCRs. However, in contrast to previous studies, our data suggest that upon sustained receptor stimulation GASP-1 stimulates recycling rather than receptor degradation.

  20. The behavioral economics of drug self-administration: A review and new analytical approach for within-session procedures

    Science.gov (United States)

    Bentzley, Brandon S.; Fender, Kimberly M.; Aston-Jones, Gary

    2012-01-01

    Rationale Behavioral-economic demand curve analysis offers several useful measures of drug self-administration. Although generation of demand curves previously required multiple days, recent within-session procedures allow curve construction from a single 110-min cocaine self-administration session, making behavioral-economic analyses available to a broad range of self-administration experiments. However, a mathematical approach of curve fitting has not been reported for the within-session threshold procedure. Objectives We review demand curve analysis in drug self-administration experiments and provide a quantitative method for fitting curves to single-session data that incorporates relative stability of brain drug concentration. Methods Sprague-Dawley rats were trained to self-administer cocaine, and then tested with the threshold procedure in which the cocaine dose was sequentially decreased on a fixed ratio-1 schedule. Price points (responses/mg cocaine) outside of relatively stable brain cocaine concentrations were removed before curves were fit. Curve-fit accuracy was determined by the degree of correlation between graphical and calculated parameters for cocaine consumption at low price (Q0) and the price at which maximal responding occurred (Pmax). Results Removing price points that occurred at relatively unstable brain cocaine concentrations generated precise estimates of Q0 and resulted in Pmax values with significantly closer agreement with graphical Pmax than conventional methods. Conclusion The exponential demand equation can be fit to single-session data using the threshold procedure for cocaine self-administration. Removing data points that occur during relatively unstable brain cocaine concentrations resulted in more accurate estimates of demand curve slope than graphical methods, permitting a more comprehensive analysis of drug self-administration via a behavioral-economic framework. PMID:23086021

  1. Dopamine decreases NMDA currents in the oval bed nucleus of the stria terminalis of cocaine self-administering rats.

    Science.gov (United States)

    Krawczyk, Michal; deBacker, Julian; Mason, Xenos; Jones, Andrea A; Dumont, Eric C

    2014-06-03

    Dopamine (DA) and N-methyl-D-aspartate receptors (NMDARs) contribute in the neural processes underlying drug-driven behaviors. DA is a potent modulator of NMDAR, but few studies have investigated the functional interaction between DA and NMDAR in the context of substance abuse. We combined the rat model of cocaine self-administration with brain slice electrophysiology to study DA modulation of NMDA currents in the oval bed nucleus of the stria terminalis (ovBNST), a dense DA terminal field involved in maintenance of cocaine self-administration amongst other drug related behaviors. Long-Evans rats self-administered intravenous cocaine (0.75 mg/kg/injection) on a progressive ratio (PR) schedule of reinforcement for 15 days and whole-cell patch-clamp recordings were done on the 16th day. DA reduced NMDA currents in brain-slices from cocaine self-administering rats, but not in those of drug-naïve and sucrose self-administering, or when cocaine exposure was passive (yoked), revealing a mechanism unique to voluntary cocaine intake. DA reduced NMDA currents by activating G-protein-coupled D1- and D2-like receptors that converged on phospholipase C and protein phosphatases. Accordingly, our study reveals a mechanism that may contribute to dysfunctional synaptic plasticity associated with drug-driven behaviors during acute withdrawal.

  2. Metabotropic glutamate receptor 7 modulates the rewarding effects of cocaine in rats: involvement of a ventral pallidal GABAergic mechanism.

    Science.gov (United States)

    Li, Xia; Li, Jie; Peng, Xiao-Qing; Spiller, Krista; Gardner, Eliot L; Xi, Zheng-Xiong

    2009-06-01

    The metabotropic glutamate receptor 7 (mGluR7) has received much attention as a potential target for the treatment of epilepsy, major depression, and anxiety. In this study, we investigated the possible involvement of mGluR7 in cocaine reward in animal models of drug addiction. Pretreatment with the selective mGluR7 allosteric agonist N,N'-dibenzyhydryl-ethane-1,2-diamine dihydrochloride (AMN082; 1-20 mg/kg, i.p.) dose-dependently inhibited cocaine-induced enhancement of electrical brain-stimulation reward and intravenous cocaine self-administration under both fixed-ratio and progressive-ratio reinforcement conditions, but failed to alter either basal or cocaine-enhanced locomotion or oral sucrose self-administration, suggesting a specific inhibition of cocaine reward. Microinjections of AMN082 (1-5 microg/microl per side) into the nucleus accumbens (NAc) or ventral pallidum (VP), but not dorsal striatum, also inhibited cocaine self-administration in a dose-dependent manner. Intra-NAc or intra-VP co-administration of 6-(4-methoxyphenyl)-5-methyl-3-pyridin-4-ylisoxazolo[4,5-c]pyridin-4(5H)-one (MMPIP, 5 microg/microl per side), a selective mGluR7 allosteric antagonist, significantly blocked AMN082's action, suggesting an effect mediated by mGluR7 in these brain regions. In vivo microdialysis demonstrated that cocaine (10 mg/kg, i.p.) priming significantly elevated extracellular DA in the NAc or VP, while decreasing extracellular GABA in VP (but not in NAc). AMN082 pretreatment selectively blocked cocaine-induced changes in extracellular GABA, but not in DA, in both naive rats and cocaine self-administration rats. These data suggest: (1) mGluR7 is critically involved in cocaine's acute reinforcement; (2) GABA-, but not DA-, dependent mechanisms in the ventral striatopallidal pathway appear to underlie AMN082's actions; and (3) AMN082 or other mGluR7-selective agonists may be useful in the treatment of cocaine addiction.

  3. Acute and chronic effects of the M1/M4-preferring muscarinic agonist xanomeline on cocaine vs. food choice in rats.

    Science.gov (United States)

    Thomsen, Morgane; Fulton, Brian S; Caine, S Barak

    2014-02-01

    We previously showed that the M1/M4-preferring muscarinic agonist xanomeline can acutely attenuate or eliminate cocaine self-administration in mice. Medications used to treat addictions will arguably be administered in (sub)chronic or repeated regimens. Tests of acute effects often fail to predict chronic effects, highlighting the need for chronic testing of candidate medications. Rats were trained to lever press under a concurrent FR5 FR5 schedule of intravenous cocaine and food reinforcement. Once baseline behavior stabilized, the effects of 7 days once-daily injections of xanomeline were evaluated. Xanomeline pretreatment dose-dependently (1.8-10 mg/kg/day) shifted the dose-effect curve for cocaine rightward (up to 5.6-fold increase in A 50), with reallocation of behavior to the food-reinforced lever. There was no indication of tolerance, rather effects grew over days. The suppression of cocaine choice appeared surmountable at high cocaine doses, and xanomeline treatment did not significantly decrease total-session cocaine or food intake. In terms of xanomeline's potential for promoting abstinence from cocaine in humans, the findings were mixed. Xanomeline did produce reallocation of behavior from cocaine to food with a robust increase in food reinforcers earned at some cocaine/xanomeline dose combinations. However, effects appeared surmountable, and food-maintained behavior was also decreased at some xanomeline/cocaine dose combinations, suggesting clinical usefulness may be limited. These data nevertheless support the notion that chronic muscarinic receptor stimulation can reduce cocaine self-administration. Future studies should show whether ligands with higher selectivity for M1 or M1/M4 subtypes would be less limited by undesired effects and can achieve higher efficacy.

  4. Cues paired with either rapid or slower self-administered cocaine injections acquire similar conditioned rewarding properties.

    Directory of Open Access Journals (Sweden)

    Anne-Noël Samaha

    Full Text Available The faster drugs of abuse reach the brain, the more addictive they can be. It is not known why this is. Environmental stimuli associated with drugs can promote the development and persistence of addiction by invigorating and precipitating drug-seeking behaviour. We determined, therefore, whether cues associated with the self-administration of rapidly delivered cocaine (injected intravenously over 5 versus 90 seconds would acquire greater conditioned rewarding properties, as assessed by the performance of an operant response reinforced solely by the cues. Rats nose-poked for intravenous cocaine infusions delivered either over 5 or 90 seconds. Discrete visual cues accompanied each infusion. The rats could then press a lever to obtain the cues--now a conditioned reward--or an inactive lever. Rats in both the 5- and 90-second groups pressed more on the active versus inactive lever following extensive (24 sessions but not following limited (3 sessions self-administration training. There were no group differences in this behaviour. Following withdrawal from cocaine self-administration, lever discrimination progressively abated in both groups and was lost by withdrawal day 30. However, the rewarding properties of the cues were not "forgotten" because on withdrawal days 32-33, amphetamine selectively enhanced active-lever pressing, and did so to a similar extent in both groups. Thus, cues paired with rapid or slower cocaine delivery acquire similar conditioned rewarding properties. We conclude, therefore, that the rapid delivery of cocaine to the brain promotes addiction by mechanisms that might not involve a greater ability of drug cues to control behaviour.

  5. Noribogaine reduces nicotine self-administration in rats.

    Science.gov (United States)

    Chang, Qing; Hanania, Taleen; Mash, Deborah C; Maillet, Emeline L

    2015-06-01

    Noribogaine, a polypharmacological drug with activities at opioid receptors, ionotropic nicotinic receptors, and serotonin reuptake transporters, has been investigated for treatment of substance abuse-related disorders. Smoking cessation has major benefits for both individuals and society, therefore the aim of this study was to evaluate the potential of noribogaine for use as a treatment for nicotine dependence. Adult male Sprague-Dawley rats were trained to self-administer nicotine intravenous. After initial food pellet training, followed by 26 sessions of nicotine self-administration training, the rats were administered noribogaine (12.5, 25 or 50 mg/kg orally), noribogaine vehicle, varenicline or saline using a within-subject design with a Latin square test schedule. Noribogaine dose-dependently decreased nicotine self-administration by up to 64% of saline-treated rats' levels and was equi-effective to 1.7 mg/kg intraperitoneal varenicline. Noribogaine was less efficient at reducing food pellets self-administration than at nicotine self-administration, inhibiting the nondrug reinforcing effects of palatable pellets by 23% at the highest dose. These results suggest that noribogaine dose-dependently attenuates drug-taking behavior for nicotine, attenuates the reinforcing effects of nicotine and is comparable to varenicline power in that regard. The findings from the present study hold promise for a new therapy to aid smoking cessation.

  6. MDMA reinstates cocaine-seeking behaviour in mice.

    Science.gov (United States)

    Trigo, José Manuel; Orejarena, Maria Juliana; Maldonado, Rafael; Robledo, Patricia

    2009-06-01

    MDMA effects are mediated by monoaminergic systems, which seem to play a central role in cocaine craving and relapse. CD1 mice trained to self-administer cocaine (1 mg/kg/infusion) underwent an extinction procedure in which the cues contingent with drug self-administration remained present. Mice achieving extinction were injected with MDMA (10 mg/kg), d-amphetamine (1 and 2 mg/kg) or saline and tested for reinstatement. Acute MDMA, but not d-amphetamine or saline reinstated cocaine-seeking behaviour in mice in which cocaine self-administration and contingent cues were previously extinguished. Acute MDMA can reinstate cocaine-seeking behaviour in mice.

  7. Comparison of the effects of methamphetamine, bupropion, and methylphenidate on the self-administration of methamphetamine by rhesus monkeys.

    Science.gov (United States)

    Schindler, Charles W; Gilman, Joanne P; Panlilio, Leigh V; McCann, David J; Goldberg, Steven R

    2011-02-01

    The effectiveness of methadone as a treatment for opioid abuse and nicotine preparations as treatments for tobacco smoking has led to an interest in developing a similar strategy for treating psychostimulant abuse. The current study investigated the effects of three such potential therapies on intravenous methamphetamine self-administration (1 - 30 μg/kg/injection) in rhesus monkeys. When given as a presession intramuscular injection, a high dose of methamphetamine (1.0 mg/kg) decreased intravenous methamphetamine self-administration but did not affect responding for a food reinforcer during the same sessions. However, the dose of intramuscular methamphetamine required to reduce intravenous methamphetamine self-administration exceeded the cumulative amount taken during a typical self-administration session, and pretreatment with a low dose of methamphetamine (0.3 mg/kg) actually increased self-administration in some monkeys at the lower self-administration dose. Like pretreatment with methamphetamine, pretreatment with bupropion (3.2 mg/kg) decreased methamphetamine self-administration but did not affect responding for food. Pretreatment with methylphenidate (0.56 mg/kg) did not significantly alter methamphetamine self-administration. These results suggest that some agonist-like agents can decrease methamphetamine self-administration. Although the most robust effects occurred with a high dose of methamphetamine, safety and abuse liability considerations suggest that bupropion should also be considered for further evaluation as a methamphetamine addiction treatment.

  8. Sensitized nucleus accumbens dopamine terminal responses to methylphenidate and dopamine transporter releasers after intermittent-access self-administration.

    Science.gov (United States)

    Calipari, Erin S; Jones, Sara R

    2014-07-01

    Long-access methylphenidate (MPH) self-administration has been shown to produce enhanced amphetamine potency at the dopamine transporter and concomitant changes in reinforcing efficacy, suggesting that MPH abuse may change the dopamine system in a way that promotes future drug abuse. While long-access self-administration paradigms have translational validity for cocaine, it may not be as relevant a model of MPH abuse, as it has been suggested that people often take MPH intermittently. Although previous work outlined the neurochemical and behavioral consequences of long-access MPH self-administration, it was not clear whether intermittent access (6 h session; 5 min access/30 min) would result in similar changes. For cocaine, long-access self-administration resulted in tolerance to cocaine's effects on dopamine and behavior while intermittent-access resulted in sensitization. Here we assessed the neurochemical consequences of intermittent-access MPH self-administration on dopamine terminal function. We found increased maximal rates of uptake, increased stimulated release, and subsensitive D2-like autoreceptors. Consistent with previous work using extended-access MPH paradigms, the potencies of amphetamine and MPH, but not cocaine, were increased, demonstrating that unlike cocaine, MPH effects were not altered by the pattern of intake. Although the potency results suggest that MPH may share properties with releasers, dopamine release was increased following acute application of MPH, similar to cocaine, and in contrast to the release decreasing effects of amphetamine. Taken together, these data demonstrate that MPH exhibits properties of both blockers and releasers, and that the compensatory changes produced by MPH self-administration may increase the abuse liability of amphetamines, independent of the pattern of administration.

  9. Low startle magnitude may be a behavioral marker of vulnerability to cocaine addiction.

    Science.gov (United States)

    Wheeler, Marina G; Duncan, Erica; Davis, Michael

    2017-01-01

    Cocaine addicted men have low startle magnitude persisting during prolonged abstinence. Low startle rats show greater cocaine self-administration than high startle rats. Low startle may be a marker of a vulnerability to heightened cocaine-related behaviors in rats and similarly may be a marker of vulnerability to cocaine addiction in humans.

  10. Inhibition of NAALADase by 2-PMPA attenuates cocaine-induced relapse in rats: a NAAG-mGluR2/3-mediated mechanism.

    Science.gov (United States)

    Xi, Zheng-Xiong; Li, Xia; Peng, Xiao-Qing; Li, Jie; Chun, Lauren; Gardner, Eliot L; Thomas, Ajit G; Slusher, Barbara S; Ashby, Charles R

    2010-01-01

    Pharmacological activation of group II metabotropic glutamate receptors (mGluR2/3) inhibits cocaine self-administration and reinstatement of drug-seeking behavior, suggesting a possible use of mGluR2/3 agonists in the treatment of cocaine dependence. In this study, we investigated whether elevation of the endogenous mGluR2/3 ligand N-acetyl-aspartatylglutamate (NAAG) levels by the N-acetylated-alpha-linked-acidic dipeptidase inhibitor 2-(phosphonomethyl)pentanedioic acid (2-PMPA) attenuates cocaine self-administration and cocaine-induced reinstatement of drug seeking. N-acetylated-alpha-linked-acidic dipeptidase is a NAAG degradation enzyme that hydrolyzes NAAG to N-acetylaspartate and glutamate. Systemic administration of 2-PMPA (10-100 mg/kg, i.p.) inhibited intravenous self-administration maintained by low unit doses of cocaine and cocaine (but not sucrose)-induced reinstatement of drug-seeking behavior. Microinjections of 2-PMPA (3-5 microg/side) or NAAG (3-5 microg/side) into the nucleus accumbens (NAc), but not into the dorsal striatum, also inhibited cocaine-induced reinstatement, an effect that was blocked by intra-NAc injection of LY341495, a selective mGluR2/3 antagonist. In vivo microdialysis demonstrated that 2-PMPA (10-100 mg/kg, i.p.) produced a dose-dependent reduction in both extracellular dopamine (DA) and glutamate, an effect that was also blocked by LY341495. Finally, pre-treatment with 2-PMPA partially attenuated cocaine-enhanced extracellular NAc DA, while completely blocking cocaine-enhanced extracellular NAc glutamate in rats during reinstatement testing. Intra-NAc perfusion of LY341495 blocked 2-PMPA-induced reductions in cocaine-enhanced extracellular NAc glutamate, but not DA. These findings suggest that 2-PMPA is effective in attenuating cocaine-induced reinstatement of drug-seeking behavior, likely by attenuating cocaine-induced increases in NAc DA and glutamate via pre-synaptic mGluR2/3s.

  11. Distinct contributions of dopamine in the dorsolateral striatum and nucleus accumbens shell to the reinforcing properties of cocaine

    National Research Council Canada - National Science Library

    Veeneman - Rijkens, M.M.J; Broekhoven, M.H; Damsteegt, R; Vanderschuren, L.J.M.J

    .... Therefore, we systematically investigated the involvement of dopamine in dorsal and ventral striatal regions in cocaine self-administration, using various schedules of reinforcement in animals...

  12. Rapid fluctuations in extracellular brain glucose levels induced by natural arousing stimuli and intravenous cocaine: fueling the brain during neural activation

    Science.gov (United States)

    Lenoir, Magalie

    2012-01-01

    Glucose, a primary energetic substrate for neural activity, is continuously influenced by two opposing forces that tend to either decrease its extracellular levels due to enhanced utilization in neural cells or increase its levels due to entry from peripheral circulation via enhanced cerebral blood flow. How this balance is maintained under physiological conditions and changed during neural activation remains unclear. To clarify this issue, enzyme-based glucose sensors coupled with high-speed amperometry were used in freely moving rats to evaluate fluctuations in extracellular glucose levels induced by brief audio stimulus, tail pinch (TP), social interaction with another rat (SI), and intravenous cocaine (1 mg/kg). Measurements were performed in nucleus accumbens (NAcc) and substantia nigra pars reticulata (SNr), which drastically differ in neuronal activity. In NAcc, where most cells are powerfully excited after salient stimulation, glucose levels rapidly (latency 2–6 s) increased (30–70 μM or 6–14% over baseline) by all stimuli; the increase differed in magnitude and duration for each stimulus. In SNr, where most cells are transiently inhibited by salient stimuli, TP, SI, and cocaine induced a biphasic glucose response, with the initial decrease (−20–40 μM or 5–10% below baseline) followed by a reboundlike increase. The critical role of neuronal activity in mediating the initial glucose response was confirmed by monitoring glucose currents after local microinjections of glutamate (GLU) or procaine (PRO). While intra-NAcc injection of GLU transiently increased glucose levels in this structure, intra-SNr PRO injection resulted in rapid, transient decreases in SNr glucose. Therefore, extracellular glucose levels in the brain change very rapidly after physiological and pharmacological stimulation, the response is structure specific, and the pattern of neuronal activity appears to be a critical factor determining direction and magnitude of physiological

  13. Examination of cocaine dose in a preclinical model of natural reward devaluation by cocaine.

    Science.gov (United States)

    Green, Jennifer L; Dykstra, Linda A; Carelli, Regina M

    2015-06-01

    In a preclinical model of natural reward devaluation by cocaine, taste cues elicit aversive taste reactivity when they predict impending but delayed cocaine self-administration. Here, we investigated this negative affective state as a function of cocaine dose. Male, Sprague-Dawley rats were given 45 brief intraoral infusions of a 0.15% saccharin solution before 2 h cocaine self-administration for 14 days. Rats were video recorded; taste reactivity and patterns of self-administration were quantified on the first and last days. On day 14, a significant decrease in appetitive taste reactivity and increase in aversive taste reactivity was observed (compared with day 1) that did not vary as a function of cocaine dose. In contrast, patterns of cocaine self-administration (i.e. the total number of lever presses and load-up behavior) varied as a function of dose across days. Further, load-up behavior was positively correlated with aversive taste reactivity (i.e. gapes) on day 14 across all doses tested. Collectively, these findings indicate that the emergence of negative affect in this preclinical model is not dependent on cocaine dose.

  14. Prenatal and postnatal cocaine exposure predict teen cocaine use.

    Science.gov (United States)

    Delaney-Black, Virginia; Chiodo, Lisa M; Hannigan, John H; Greenwald, Mark K; Janisse, James; Patterson, Grace; Huestis, Marilyn A; Partridge, Robert T; Ager, Joel; Sokol, Robert J

    2011-01-01

    Preclinical studies have identified alterations in cocaine and alcohol self-administration and behavioral responses to pharmacological challenges in adolescent offspring following prenatal exposure. To date, no published human studies have evaluated the relation between prenatal cocaine exposure and postnatal adolescent cocaine use. Human studies of prenatal cocaine-exposed children have also noted an increase in behaviors previously associated with substance use/abuse in teens and young adults, specifically childhood and teen externalizing behaviors, impulsivity, and attention problems. Despite these findings, human research has not addressed prior prenatal exposure as a potential predictor of teen drug use behavior. The purpose of this study was to evaluate the relations between prenatal cocaine exposure and teen cocaine use in a prospective longitudinal cohort (n=316) that permitted extensive control for child, parent and community risk factors. Logistic regression analyses and Structural Equation Modeling revealed that both prenatal exposure and postnatal parent/caregiver cocaine use were uniquely related to teen use of cocaine at age 14 years. Teen cocaine use was also directly predicted by teen community violence exposure and caregiver negativity, and was indirectly related to teen community drug exposure. These data provide further evidence of the importance of prenatal exposure, family and community factors in the intergenerational transmission of teen/young adult substance abuse/use. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. A Double-blind, Placebo-controlled Assessment of the Safety of Potential Interactions Between Intravenous Cocaine, Ethanol, and Oral Disulfiram

    Science.gov (United States)

    Roache, John D.; Kahn, Roberta; Newton, Thomas F.; Wallace, Christopher L.; Murff, William L.; De La Garza, Richard; Rivera, Oscar; Anderson, Ann; Mojsiak, Jurij; Elkashef, Ahmed

    2011-01-01

    BACKGROUND A majority of cocaine addicts have a comorbid alcohol use disorder. Previous studies demonstrated efficacy of disulfiram in the treatment of cocaine dependence among patients with comorbid alcohol use disorder or opioid dependence. However, the cardiac risks of a disulfiram-ethanol reaction (DER) in individuals who drink, when coupled with the cardiac effects of cocaine, could result in significant toxicity or lethality due to the 3-way drug interaction. AIMS This study examined the safety of combining cocaine (30 mg i.v.) and ethanol (0.4 g/kg i.v.) in disulfiram-treated (0, 250, and 500 mg/d, p.o.) cocaine-dependent research volunteers. RESULTS The results showed that disulfiram did not enhance the cardiovascular effects of cocaine and may have reduced the subjective high from cocaine. In contrast, ethanol produced adverse ECG changes including QTc prolongation and a DER consisting of hypotension, tachycardia, nausea, and flushing in disulfiram-treated subjects. The severity of the DER was related to disulfiram dose and the trial with 500 mg/d was stopped prematurely due to safety concerns. The DER-related hypotension and tachycardia seen with ethanol infusion alone in disulfiram-treated subjects, was not exacerbated when combined with cocaine. In fact, cocaine tended to counteract the ethanol-related hypotension though it did exacerbate the tachycardia in two of seven subjects. CONCLUSIONS Though conclusions are limited by the moderate doses of cocaine, ethanol, and disulfiram tested, the data do suggest that the risks of the moderate use of cocaine and ethanol in individuals treated with moderate doses of disulfiram (≤250 mg/d) may not be as problematic as some may assume. PMID:21696894

  16. Clavulanic acid enhances glutamate transporter subtype I (GLT-1) expression and decreases reinforcing efficacy of cocaine in mice.

    Science.gov (United States)

    Kim, Jae; John, Joel; Langford, Dianne; Walker, Ellen; Ward, Sara; Rawls, Scott M

    2016-03-01

    The β-lactam antibiotic ceftriaxone (CTX) reduces cocaine reinforcement and relapse in preclinical assays through a mechanism involving activation of glutamate transporter subtype 1 (GLT-1). However, its poor brain penetrability and intravenous administration route may limit its therapeutic utility for indications related to CNS diseases. An alternative is clavulanic acid (CA), a structural analog of CTX that retains the β-lactam core required for GLT-1 activity but displays enhanced brain penetrability and oral activity relative to CTX. Here, we tested the hypothesis that CA (1, 10 mg/kg ip) would enhance GLT-1 expression and decrease cocaine self-administration (SA) in mice, but at lower doses than CTX. Experiments revealed that GLT-1 transporter expression in the nucleus accumbens of mice treated with repeated CA (1, 10 mg/kg) was enhanced relative to saline-treated mice. Repeated CA treatment (1 mg/kg) reduced the reinforcing efficacy of cocaine (0.56 mg/kg/inf) in mice maintained on a progressive-ratio (PR) schedule of reinforcement but did not affect acquisition of cocaine SA under fixed-ratio responding or acquisition or retention of learning. These findings suggest that the β-lactamase inhibitor CA can activate the cellular glutamate reuptake system in the brain reward circuit and reduce cocaine's reinforcing efficacy at 100-fold lower doses than CTX.

  17. [Cocaine - Characteristics and addiction].

    Science.gov (United States)

    Girczys-Połedniok, Katarzyna; Pudlo, Robert; Jarząb, Magdalena; Szymlak, Agnieszka

    Cocaine use leads to health, social and legal problems. The aim of this paper is to discuss cocaine action, addicts characteristics, use patterns and consequences, as well as addiction treatment methods. A literature review was based on the Medline, PubMed, Polish Medical Bibliography databases and the Silesian Library resources. The Police and Central Statistical Office statistics, as well as the World Health Organization, the European Monitoring Centre for Drugs and Drug Addiction and the National Office for Combating Drug Addiction reports were used. Cocaine leads to mood improvement, appetite decrease, physical and intellectual activity enhancement, euphoria, inflated self-esteem, social networking ease and increased sexual desire. Cocaine hydrochloride is mainly used intranasaly, but also as intravenous and subcutaneous injections. Cocaine use and first addiction treatment fall in later age compared to other psychoactive substances. There is a high men to women ratio among addicts. There is a relationship between cocaine addiction, the presence of other disorders and genetic predisposition to addiction development. Polish reports indicate higher popularity of cocaine among people with a high economic and social status. Although Poland is a country with the low percentage of cocaine use, its popularity is growing. The consequences of cocaine use concern somatic and mental health problems, socioeconomic and legal conditions. The drug plays a role in crimes and traffic accidents. Because of the risks associated with cocaine use, it has been listed in a register of drugs attached to the Act on Counteracting Drug Addiction. Addiction treatment includes psychological, pharmacological and harm reduction strategies. Med Pr 2016;67(4):537-544.

  18. Maternal environment influences cocaine intake in adulthood in a genotype-dependent manner.

    Directory of Open Access Journals (Sweden)

    Rixt van der Veen

    Full Text Available BACKGROUND: Accumulating epidemiological evidence points to the role of genetic background as a modulator of the capacity of adverse early experiences to give rise to mental illness. However, direct evidence of such gene-environment interaction in the context of substance abuse is scarce. In the present study we investigated whether the impact of early life experiences on cocaine intake in adulthood depends on genetic background. In addition, we studied other behavioral dimensions associated with drug abuse, i.e. anxiety- and depression-related behaviors. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, we manipulated the maternal environment of two inbred mouse strains, the C57BL/6J and DBA/2J by fostering them with non-related mothers, i.e. the C3H/HeN and AKR strains. These mother strains show respectively high and low pup-oriented behavior. As adults, C57BL/6J and DBA/2J were tested either for cocaine intravenous self-administration or in the elevated plus-maze and forced swim test (FST. We found that the impact of maternal environment on cocaine use and a depression-related behavior depends upon genotype, as cocaine self-administration and behavior in the FST were influenced by maternal environment in DBA/2J, but not in C57BL/6J mice. Anxiety was not influenced by maternal environment in either strain. CONCLUSIONS/SIGNIFICANCE: Our experimental approach could contribute to the identification of the psychobiological factors determining the susceptibility or the resilience of certain individuals to develop psychopathologies.

  19. Reinstatement in a Cocaine vs. Food Choice Situation: Reversal of Preference between Drug and Non-Drug Rewards

    OpenAIRE

    Brendan J. Tunstall; Kearns, David N.

    2013-01-01

    Recent studies (for review see Ahmed, 2010; 2012) show that when given a mutually exclusive choice between cocaine and food, rats almost exclusively choose food. The present experiment investigated potential shifts in preference between levers associated with either food or cocaine which might occur during extinction (food and cocaine no longer available) and during footshock-induced, cocaine-primed, and food-primed reinstatement. During self-administration sessions where food and cocaine wer...

  20. The role of endocannabinoid transmission in cocaine addiction.

    Science.gov (United States)

    Arnold, Jonathon C

    2005-06-01

    Research is beginning to outline a role for the endocannabinoid system in cocaine addiction. Human and animal studies indicate that exogenous cannabinoids modulate the acute rewarding effects of cocaine. These studies, however, cannot directly investigate the necessity of endocannabinoid transmission in cocaine addiction. Studies that do offer a direct assessment show that neither pharmacological antagonism nor deletion of the CB1 receptor alters the acute rewarding effects of cocaine. In contrast, CB1 receptors appear to be involved in the association of cocaine reward with environmental cues and reinstatement of cocaine self-administration. Together, these results point to CB1 receptor antagonists as potential anti-craving compounds in the treatment of cocaine addiction. Given the limitations of human population studies, animal research may be useful in discerning causal inferences between cannabis and cocaine use. While animal research suggests cannabis use may precipitate cocaine relapse, cross-sensitization between cannabinoids and cocaine has not been demonstrated and CB1 receptors do not mediate behavioral sensitization to cocaine. The effect of acute or chronic cocaine on endocannabinoid transmission in reward-related areas of the brain is relatively under-researched. Acute cocaine administration increases anandamide levels in the striatum, an effect that is mediated by dopamine D2-like receptors. Conversely, chronic cocaine exposure has no effect on anandamide, but decreases 2-arachidonylglycerol levels in the limbic forebrain. This review highlights research indicating that the endocannabinoid system may subserve certain aspects of cocaine addiction and suggests avenues for future investigation.

  1. A Role for Sigma Receptors in Stimulant Self Administration and Addiction

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    Shang-Yi Tsai

    2011-06-01

    Full Text Available Sigma1 receptors (σ1Rs represent a structurally unique class of intracellular proteins that function as chaperones. σ1Rs translocate from the mitochondria-associated membrane to the cell nucleus or cell membrane, and through protein-protein interactions influence several targets, including ion channels, G-protein-coupled receptors, lipids, and other signaling proteins. Several studies have demonstrated that σR antagonists block stimulant-induced behavioral effects, including ambulatory activity, sensitization, and acute toxicities. Curiously, the effects of stimulants have been blocked by σR antagonists tested under place-conditioning but not self-administration procedures, indicating fundamental differences in the mechanisms underlying these two effects. The self administration of σR agonists has been found in subjects previously trained to self administer cocaine. The reinforcing effects of the σR agonists were blocked by σR antagonists. Additionally, σR agonists were found to increase dopamine concentrations in the nucleus accumbens shell, a brain region considered important for the reinforcing effects of abused drugs. Although the effects of the σR agonist, DTG, on dopamine were obtained at doses that approximated those that maintained self administration behavior those of another agonist, PRE-084 required higher doses. The effects of DTG were antagonized by non-selective or a preferential σ2R antagonist but not by a preferential σ1R antagonist. The effects of PRE-084 on dopamine were insensitive to σR antagonists. The data suggest that the self administration of σR agonists is independent of dopamine and the findings are discussed in light of a hypothesis that cocaine has both intracellular actions mediated by σRs, as well as extracellular actions mediated through conventionally studied mechanisms. The co-activation and potential interactions among these mechanisms, in particular those involving the intracellular chaperone

  2. Overexpression of CREB in the nucleus accumbens shell increases cocaine reinforcement in self-administering rats.

    Science.gov (United States)

    Larson, Erin B; Graham, Danielle L; Arzaga, Rose R; Buzin, Nicole; Webb, Joseph; Green, Thomas A; Bass, Caroline E; Neve, Rachael L; Terwilliger, Ernest F; Nestler, Eric J; Self, David W

    2011-11-09

    Chronic exposure to addictive drugs enhances cAMP response element binding protein (CREB)-regulated gene expression in nucleus accumbens (NAc), and these effects are thought to reduce the positive hedonic effects of passive cocaine administration. Here, we used viral-mediated gene transfer to produce short- and long-term regulation of CREB activity in NAc shell of rats engaging in volitional cocaine self-administration. Increasing CREB expression in NAc shell markedly enhanced cocaine reinforcement of self-administration behavior, as indicated by leftward (long-term) and upward (short-term) shifts in fixed ratio dose-response curves. CREB also increased the effort exerted by rats to obtain cocaine on more demanding progressive ratio schedules, an effect highly correlated with viral-induced modulation of BDNF protein in the NAc shell. CREB enhanced cocaine reinforcement when expressed either throughout acquisition of self-administration or when expression was limited to postacquisition tests, indicating a direct effect of CREB independent of reinforcement-related learning. Downregulating endogenous CREB in NAc shell by expressing a short hairpin RNA reduced cocaine reinforcement in similar tests, while overexpression of a dominant-negative CREB(S133A) mutant had no significant effect on cocaine self-administration. Finally, increasing CREB expression after withdrawal from self-administration enhanced cocaine-primed relapse, while reducing CREB levels facilitated extinction of cocaine seeking, but neither altered relapse induced by cocaine cues or footshock stress. Together, these findings indicate that CREB activity in NAc shell increases the motivation for cocaine during active self-administration or after withdrawal from cocaine. Our results also highlight that volitional and passive drug administration can lead to substantially different behavioral outcomes.

  3. Activin receptor signaling regulates cocaine-primed behavioral and morphological plasticity.

    Science.gov (United States)

    Gancarz, Amy M; Wang, Zi-Jun; Schroeder, Gabrielle L; Damez-Werno, Diane; Braunscheidel, Kevin M; Mueller, Lauren E; Humby, Monica S; Caccamise, Aaron; Martin, Jennifer A; Dietz, Karen C; Neve, Rachael L; Dietz, David M

    2015-07-01

    Activin receptor signaling, including the transcription factor Smad3, was upregulated in the rat nucleus accumbens (NAc) shell following withdrawal from cocaine. Direct genetic and pharmacological manipulations of this pathway bidirectionally altered cocaine seeking while governing morphological plasticity in NAc neurons. Thus, Activin/Smad3 signaling is induced following withdrawal from cocaine, and such regulation may be a key molecular mechanism underlying behavioral and cellular plasticity in the brain following cocaine self-administration.

  4. An overview of cocaethylene, an alcohol-derived, psychoactive, cocaine metabolite.

    Science.gov (United States)

    Landry, M J

    1992-01-01

    Cocaethylene is a psychoactive ethyl homologue of cocaine, and is formed exclusively during the coadministration of cocaine and alcohol. Not a natural alkaloid of the coca leaf, cocaethylene can be identified in the urine, blood, hair, and neurological and liver tissue samples of individuals who have consumed both cocaine and alcohol. With a pharmacologic profile similar to cocaine, it can block the dopamine transporter on dopaminergic presynaptic nerve terminals in the brain. It increases dopamine synaptic content, provoking enhanced postsynaptic receptor stimulation, resulting in euphoria, reinforcement, and self-administration. Equipotent to cocaine with regard to dopamine transporter affinity, cocaethylene appears to be far less potent than cocaine with regard to serotonin transporter binding. Lacking the serotonergic-related inhibitory mechanism, cocaethylene appears to be more euphorigenic and rewarding than cocaine. Synthesized and administered cocaethylene has a behavioral stimulation profile similar to cocaine. Cocaethylene has been shown to be less potent and equipotent to cocaine, and alcohol plus cocaine produces more stimulatory locomotor behavior in mice than either drug alone. Equipotent to cocaine with regard to primate reinforcement and self-administration, cocaethylene can substitute for cocaine in drug discrimination studies, and can produce stimulation of operant conditioning in rats. With regard to lethality, cocaethylene has been shown to be more potent than cocaine in mice and rats. The combination of cocaine and alcohol appears to exert more cardiovascular toxicity than either drug alone in humans. Alcohol appears to potentiate cocaine hepatotoxicity in both humans and mice.

  5. Behavioral Determinants of Cannabinoid Self-Administration in Old World Monkeys.

    Science.gov (United States)

    John, William S; Martin, Thomas J; Nader, Michael A

    2017-02-01

    Reinforcing effects of Δ(9)-tetrahydrocannabinol (THC), the primary active ingredient in marijuana, as assessed with self-administration (SA), has only been established in New World primates (squirrel monkeys). The objective of this study was to investigate some experimental factors that may enhance intravenous SA of THC and the cannabinoid receptor (CBR) agonist CP 55 940 in Old World monkeys (rhesus and cynomolgus), a species that has been used extensively in biomedical research. In one experiment, male rhesus monkeys (N=9) were trained to respond under a fixed-ratio 10 schedule of food presentation. The effects of CP 55 940 (1.0-10 μg/kg, i.v.) and THC (3.0-300 μg/kg, i.v.) on food-maintained responding and body temperature were determined in these subjects prior to giving them access to self-administer each drug. Both drugs dose-dependently decreased food-maintained responding. CP 55 940 (0.001-3.0 μg/kg) functioned as a reinforcer in three monkeys, whereas THC (0.01-10 μg/kg) did not have reinforcing effects in any subject. CP 55 940 was least potent to decrease food-maintained responding in the monkeys in which CP 55 940 functioned as a reinforcer. Next, THC was administered daily to monkeys until tolerance developed to rate-decreasing effects. When THC SA was reexamined, it functioned as a reinforcer in three monkeys. In a group of cocaine-experienced male cynomolgus monkeys (N=4), THC SA was examined under a second-order schedule of reinforcement; THC functioned as reinforcer in two monkeys. These data suggest that SA of CBR agonists may be relatively independent of their rate-decreasing effects in Old World monkeys. Understanding individual differences in vulnerability to THC SA may lead to novel treatment strategies for marijuana abuse.Neuropsychopharmacology advance online publication, 1 February 2017; doi:10.1038/npp.2017.2.

  6. Multiple Gastrointestinal Complications of Crack Cocaine Abuse

    Directory of Open Access Journals (Sweden)

    Neal Carlin

    2014-01-01

    Full Text Available Cocaine and its alkaloid free base “crack-cocaine” have long since been substances of abuse. Drug abuse of cocaine via oral, inhalation, intravenous, and intranasal intake has famously been associated with a number of medical complications. Intestinal ischemia and perforation remain the most common manifestations of cocaine associated gastrointestinal disease and have historically been associated with oral intake of cocaine. Here we find a rare case of two relatively uncommon gastrointestinal complications of hemorrhage and pancreatitis presenting within a single admission in a chronic crack cocaine abuser.

  7. A critical role for beta-endorphin in cocaine-seeking behavior.

    Science.gov (United States)

    Roth-Deri, I; Schindler, C J; Yadid, G

    2004-03-01

    Endogenous beta-endorphin levels in the brain are elevated in response to cocaine and are downstream of the mesolimbic dopaminergic system. However, beta-endorphin's direct involvement in cocaine reinforcement has not been demonstrated. In the present study, a single bilateral microinjection of anti-beta-endorphin antibodies (4 microg) to the nucleus accumbens during the maintenance phase of cocaine self-administration (1 mg/kg/infusion) significantly increased the number of active and inactive lever responses. The increase in lever responses is reminiscent of rat behavior during extinction of cocaine self-administration. Further, a cocaine dose-response demonstrates that the increased lever presses in anti-beta-endorphin antibody-injected rats was still present after substitution with a lower dose of cocaine. These findings support a critical role for beta-endorphin in the cocaine brain reward system. Copyright 2004 Lippincott Williams & Wilkins

  8. Role of GABA-active neurosteroids in the efficacy of metyrapone against cocaine addiction.

    Science.gov (United States)

    Schmoutz, Christopher D; Guerin, Glenn F; Goeders, Nicholas E

    2014-09-01

    Previous research has demonstrated a complicated role for stress and HPA axis activation in potentiating various cocaine-related behaviors in preclinical models of drug dependence. However, the investigation of several antiglucocorticoid therapies has yielded equivocal results in reducing cocaine-related behaviors, possibly because of varying mechanisms of actions. Specifically, research suggests that metyrapone (a corticosterone synthesis inhibitor) may reduce cocaine self-administration in rats via a nongenomic, extra-adrenal mechanism without altering plasma corticosterone. In the current experiments, male rats were trained to self-administer cocaine infusions and food pellets in a multiple, alternating schedule of reinforcement. Metyrapone pretreatment dose-dependently decreased cocaine self-administration as demonstrated previously. Pharmacological inhibition of neurosteroid production by finasteride had significant effects on cocaine self-administration, regardless of metyrapone pretreatment. However, metyrapone's effects on cocaine self-administration were significantly attenuated with bicuculline pretreatment, suggesting a role for GABA-active neurosteroids in cocaine-reinforced behaviors. In vitro binding data also confirmed that metyrapone does not selectively bind to GABA-related proteins. The results of these experiments support the hypothesis that metyrapone may increase neurosteroidogenesis to produce effects on cocaine-related behaviors.

  9. An antidote for acute cocaine toxicity.

    Science.gov (United States)

    Treweek, Jennifer B; Janda, Kim D

    2012-04-02

    Not only has immunopharmacotherapy grown into a field that addresses the abuse of numerous illicit substances, but also the treatment methodologies within immunopharmacotherapy have expanded from traditional active vaccination to passive immunization with anti-drug monoclonal antibodies, optimized mAb formats, and catalytic drug-degrading antibodies. Many laboratories have focused on transitioning distinct immunopharmacotherapeutics to clinical evaluation, but with respect to the indication of cocaine abuse, only the active vaccine TA-CD, which is modeled after our original cocaine hapten GNC, has been carried through to human clinical trials. The successful application of murine mAb GNC92H2 to the reversal of cocaine overdose in a mouse model prompted investigations of human immunoglobulins with the clinical potential to serve as cocaine antidotes. We now report the therapeutic utility of a superior clone, human mAb GNCgzk (K(d) = 0.18 nM), which offers a 10-fold improvement in cocaine binding affinity. The GNCgzk manifold was engineered for rapid cocaine clearance, and administration of the F(ab')₂ and Fab formats even after the appearance of acute behavioral signs of cocaine toxicity granted nearly complete prevention of lethality. Thus, contrary to the immunopharmacotherapeutic treatment of drug self-administration, minimal antibody doses were shown to counteract the lethality of a molar excess of circulating cocaine. Passive vaccination with drug-specific antibodies represents a viable treatment strategy for the human condition of cocaine overdose.

  10. Susceptibility to traumatic stress sensitizes the dopaminergic response to cocaine and increases motivation for cocaine.

    Science.gov (United States)

    Brodnik, Zachary D; Black, Emily M; Clark, Meagan J; Kornsey, Kristen N; Snyder, Nathaniel W; España, Rodrigo A

    2017-10-01

    Patients with post-traumatic stress disorder have a heightened vulnerability to developing substance use disorders; however, the biological underpinnings of this vulnerability remain unresolved. We used the predator odor stress model of post-traumatic stress disorder with segregation of subjects as susceptible or resilient based on elevated plus maze behavior and context avoidance. We then determined behavioral and neurochemical differences across susceptible, resilient, and control populations using a panel of behavioral and neurochemical assays. Susceptible subjects showed a significant increase in the motoric and dopaminergic effects of cocaine, and this corresponded with heightened motivation to self-administer cocaine. Resilient subjects did not show differences in the motoric effects of cocaine, in dopamine signaling in vivo, or in any measure of cocaine self-administration. Nonetheless, we found that these animals displayed elevations in both the dopamine release-promoting effects of cocaine and dopamine autoreceptor sensitivity ex vivo. Our results suggest that the experience of traumatic stress may produce alterations in dopamine systems that drive elevations in cocaine self-administration behavior in susceptible subjects, but may also produce both active and passive forms of resilience that function to prevent gross changes in cocaine's reinforcing efficacy in resilient subjects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Stimulation of 5-HT(1B) receptors enhances cocaine reinforcement yet reduces cocaine-seeking behavior.

    Science.gov (United States)

    Pentkowski, Nathan S; Acosta, Jazmin I; Browning, Jenny R; Hamilton, Elizabeth C; Neisewander, Janet L

    2009-09-01

    Paradoxically, stimulation of 5-HT(1B) receptors (5-HT(1B)Rs) enhances sensitivity to the reinforcing effects of cocaine but attenuates incentive motivation for cocaine as measured using the extinction/reinstatement model. We revisited this issue by examining the effects of a 5-HT(1B)R agonist, CP94253, on cocaine reinforcement and cocaine-primed reinstatement, predicting that CP94253 would enhance cocaine-seeking behavior reinstated by a low priming dose, similar to its effect on cocaine reinforcement. Rats were trained to self-administer cocaine (0.75 mg/kg, i.v.) paired with light and tone cues. For reinstatement experiments, they then underwent daily extinction training to reduce cocaine-seeking behavior (operant responses without cocaine reinforcement). Next, they were pre-treated with CP94253 (3-10 mg/kg, s.c.) and either tested for cocaine-primed (10 or 2.5 mg/kg, i.p.) or cue-elicited reinstatement of extinguished cocaine-seeking behavior. For reinforcement, effects of CP94253 (5.6 mg/kg) across a range of self-administered cocaine doses (0-1.5 mg/kg, i.v.) were examined. Cocaine dose-dependently reinstated cocaine-seeking behavior, but contrary to our prediction, CP94253 reduced reinstatement with both priming doses. Similarly, CP94253 reduced cue-elicited reinstatement. In contrast, CP94253 shifted the self-administration dose-effect curve leftward, consistent with enhanced cocaine reinforcement. When saline was substituted for cocaine, CP94253 reduced response rates (i.e. cocaine-seeking behavior). In subsequent control experiments, CP94253 decreased open-arm exploration in an elevated plus-maze suggesting an anxiogenic effect, but had no effect on locomotion or sucrose reinforcement. These results provide strong evidence that stimulation of 5-HT(1B)Rs produces opposite effects on cocaine reinforcement and cocaine-seeking behavior, and further suggest that 5-HT(1B)Rs may be a novel target for developing medications for cocaine dependence.

  12. Cocaine – Characteristics and addiction

    Directory of Open Access Journals (Sweden)

    Katarzyna Girczys-Połedniok

    2016-08-01

    Full Text Available Cocaine use leads to health, social and legal problems. The aim of this paper is to discuss cocaine action, addicts characteristics, use patterns and consequences, as well as addiction treatment methods. A literature review was based on the Medline, PubMed, Polish Medical Bibliography databases and the Silesian Library resources. The Police and Central Statistical Office statistics, as well as the World Health Organization, the European Monitoring Centre for Drugs and Drug Addiction and the National Office for Combating Drug Addiction reports were used. Cocaine leads to mood improvement, appetite decrease, physical and intellectual activity enhancement, euphoria, inflated self-esteem, social networking ease and increased sexual desire. Cocaine hydrochloride is mainly used intranasaly, but also as intravenous and subcutaneous injections. Cocaine use and first addiction treatment fall in later age compared to other psychoactive substances. There is a high men to women ratio among addicts. There is a relationship between cocaine addiction, the presence of other disorders and genetic predisposition to addiction development. Polish reports indicate higher popularity of cocaine among people with a high economic and social status. Although Poland is a country with the low percentage of cocaine use, its popularity is growing. The consequences of cocaine use concern somatic and mental health problems, socioeconomic and legal conditions. The drug plays a role in crimes and traffic accidents. Because of the risks associated with cocaine use, it has been listed in a register of drugs attached to the Act on Counteracting Drug Addiction. Addiction treatment includes psychological, pharmacological and harm reduction strategies. Med Pr 2016;67(4:537–544

  13. Enhancing glutamatergic transmission during adolescence reverses early-life stress-induced deficits in the rewarding effects of cocaine in rats.

    Science.gov (United States)

    O'Connor, Richard M; Moloney, Rachel D; Glennon, Jeffrey; Vlachou, Styliani; Cryan, John F

    2015-12-01

    Adolescence marks a critical time when the brain is highly susceptible to pathological insult yet also uniquely amenable to therapeutic intervention. It is during adolescence that the onset of the majority of psychiatric disorders, including substance use disorder (SUDs), occurs. It has been well established that stress, particularly during early development, can contribute to the pathological changes which contribute to the development of SUDs. Glutamate as the main excitatory neurotransmitter in the mammalian CNS plays a key role in various physiological processes, including reward function, and in mediating the effects of psychological stress. We hypothesised impairing glutamatergic signalling during the key adolescent period would attenuate early-life stress induced impaired reward function. To test this, we induced early-life stress in male rats using the maternal-separation procedure. During the critical adolescent period (PND25-46) animals were treated with the glutamate transporter activator, riluzole, or the NMDA receptor antagonist, memantine. Adult reward function was assessed using voluntary cocaine intake measured via intravenous self-administration. We found that early-life stress in the form of maternal-separation impaired reward function, reducing the number of successful cocaine-infusions achieved during the intravenous self-administration procedure as well impairing drug-induced reinstatement of cocaine-taking behaviour. Interestingly, riluzole and memantine treatment reversed this stress-induced impairment. These data suggest that reducing glutamatergic signalling may be a viable therapeutic strategy for treating vulnerable individuals at risk of developing SUDs including certain adolescent populations, particularly those which may have experienced trauma during early-life.

  14. Effects of phendimetrazine treatment on cocaine vs food choice and extended-access cocaine consumption in rhesus monkeys.

    Science.gov (United States)

    Banks, Matthew L; Blough, Bruce E; Fennell, Timothy R; Snyder, Rodney W; Negus, S Stevens

    2013-12-01

    There is currently no Food and Drug Administration-approved pharmacotherapy for cocaine addiction. Monoamine releasers such as d-amphetamine constitute one class of candidate medications, but clinical use and acceptance are hindered by their own high-abuse liability. Phendimetrazine (PDM) is a schedule III anorectic agent that functions as both a low-potency monoamine-uptake inhibitor and as a prodrug for the monoamine-releaser phenmetrazine (PM), and it may serve as a clinically available, effective, and safer alternative to d-amphetamine. This study determined efficacy of chronic PDM to reduce cocaine self-administration by rhesus monkeys (N=4) using a novel procedure that featured both daily assessments of cocaine vs food choice (to assess medication efficacy to reallocate behavior away from cocaine choice and toward choice of an alternative reinforcer) and 20 h/day cocaine access (to allow high-cocaine intake). Continuous 21-day treatment with ramping PDM doses (days 1-7: 0.32 mg/kg/h; days 8-21: 1.0 mg/kg/h) reduced cocaine choices, increased food choices, and nearly eliminated extended-access cocaine self-administration without affecting body weight. There was a trend for plasma PDM and PM levels to correlate with efficacy to decrease cocaine choice such that the monkey with the highest plasma PDM and PM levels also demonstrated the greatest reductions in cocaine choice. These results support further consideration of PDM as a candidate anti-cocaine addiction pharmacotherapy. Moreover, PDM may represent a novel pharmacotherapeutic approach for cocaine addiction because it may simultaneously function as both a monoamine-uptake inhibitor (via the parent drug PDM) and as a monoamine releaser (via the active metabolite PM).

  15. Effects of Acute and Chronic Treatments with Dopamine D2 and D3 Receptor Ligands on Cocaine versus Food Choice in Rats.

    Science.gov (United States)

    Thomsen, Morgane; Barrett, Andrew C; Butler, Paul; Negus, S Stevens; Caine, S Barak

    2017-07-01

    Dopamine D3 receptor ligands are potential medications for psychostimulant addiction. Medication assessment may benefit from preclinical studies that evaluate chronic medication effects on choice between an abused drug and an alternative, nondrug reinforcer. This study compared acute and chronic effects of dopamine D2- and D3-preferring ligands on choice between intravenous cocaine and palatable food in rats. Under baseline conditions, cocaine maintained dose-dependent increases in cocaine choice and reciprocal decreases in food choice. Acutely, the D2 agonist R-(-)-norpropylapomorphine (NPA) and antagonist L-741,626 [3-[[4-(4-chlorophenyl)-4-hydroxypiperidin-l-yl]methyl-1H-indole] produced leftward and rightward shifts in cocaine dose-effect curves, respectively, whereas the partial agonist terguride had no effect. All three drugs dose-dependently decreased food-maintained responding. Chronically, the effects of R-(-)-norpropylapomorphine and L-741,626 on cocaine self-administration showed marked tolerance, whereas suppression of food-reinforced behavior persisted. Acute effects of the D3 ligands were less systematic and most consistent with nonselective decreases in cocaine- and food-maintained responding. Chronically, the D3 agonist PF-592,379 [5-[(2R,5S)-5-methyl-4-propylmorpholin-2-yl]pyridin-2-amine] increased cocaine choice, whereas an intermediate dose of the D3 antagonist PG01037 [N-[(E)-4-[4-(2,3-dichlorophenyl)piperazin-1-yl]but-2-enyl]-4-pyridin-2-ylbenzamide] produced a therapeutically desirable decrease in cocaine choice early in treatment; however, tolerance to this effect developed, and lower and higher doses were ineffective. D3 ligands failed to significantly modify total cocaine intake but caused persistent decreases in food intake. Thus, D2-and D3-preferring ligands showed distinct profiles, consistent with different pharmacological actions. In addition, these results highlight the role of acute versus chronic treatment as a determinant of test

  16. AAVrh.10-Mediated Expression of an Anti-Cocaine Antibody Mediates Persistent Passive Immunization That Suppresses Cocaine-Induced Behavior

    Science.gov (United States)

    Rosenberg, Jonathan B.; Hicks, Martin J.; De, Bishnu P.; Pagovich, Odelya; Frenk, Esther; Janda, Kim D.; Wee, Sunmee; Koob, George F.; Hackett, Neil R.; Kaminsky, Stephen M.; Worgall, Stefan; Tignor, Nicole; Mezey, Jason G.

    2012-01-01

    Abstract Cocaine addiction is a major problem affecting all societal and economic classes for which there is no effective therapy. We hypothesized an effective anti-cocaine vaccine could be developed by using an adeno-associated virus (AAV) gene transfer vector as the delivery vehicle to persistently express an anti-cocaine monoclonal antibody in vivo, which would sequester cocaine in the blood, preventing access to cognate receptors in the brain. To accomplish this, we constructed AAVrh.10antiCoc.Mab, an AAVrh.10 gene transfer vector expressing the heavy and light chains of the high affinity anti-cocaine monoclonal antibody GNC92H2. Intravenous administration of AAVrh.10antiCoc.Mab to mice mediated high, persistent serum levels of high-affinity, cocaine-specific antibodies that sequestered intravenously administered cocaine in the blood. With repeated intravenous cocaine challenge, naive mice exhibited hyperactivity, while the AAVrh.10antiCoc.Mab-vaccinated mice were completely resistant to the cocaine. These observations demonstrate a novel strategy for cocaine addiction by requiring only a single administration of an AAV vector mediating persistent, systemic anti-cocaine passive immunity. PMID:22486244

  17. Electrical stimulation of the lateral habenula produces enduring inhibitory effect on cocaine seeking behavior.

    Science.gov (United States)

    Friedman, Alexander; Lax, Elad; Dikshtein, Yahav; Abraham, Lital; Flaumenhaft, Yakov; Sudai, Einav; Ben-Tzion, Moshe; Ami-Ad, Lavi; Yaka, Rami; Yadid, Gal

    2010-11-01

    The lateral habenula (LHb) is critical for modulation of negative reinforcement, punishment and aversive responses. In light of the success of deep-brain-stimulation (DBS) in the treatment of neurological disorders, we explored the use of LHb DBS as a method of intervention in cocaine self-administration, extinction, and reinstatement in rats. An electrode was implanted into the LHb and rats were trained to self-administer cocaine (21 days; 0.25-1 mg/kg) until they achieved at least three days of stable performance (as measured by daily recordings of active lever presses in self-administration cages). Thereafter, rats received DBS in the presence or absence of cocaine. DBS reduced cocaine seeking behavior during both self-administration and extinction training. DBS also attenuated the rats' lever presses following cocaine reinstatement (5-20 mg/kg) in comparison to sham-operated rats. These results were also controlled by the assessment of physical performance as measured by water self-administration and an open field test, and by evaluation of depressive-like manifestations as measured by the swim and two-bottles-choice tests. In contrast, LHb lesioned rats demonstrated increased cocaine seeking behavior as demonstrated by a delayed extinction response. In the ventral tegmental area, cocaine self-administration elevated glutamatergic receptor subunits NR1 and GluR1 and scaffolding protein PSD95, but not GABA(A)β, protein levels. Following DBS treatment, levels of these subunits returned to control values. We postulate that the effect of both LHb modulation and LHb DBS on cocaine reinforcement may be via attenuation of the cocaine-induced increase in glutaminergic input to the VTA.

  18. The Contingency of Cocaine Administration Accounts for Structural and Functional Medial Prefrontal Deficits and Increased Adrenocortical Activation

    Science.gov (United States)

    Anderson, Rachel M.; Cosme, Caitlin V.; Glanz, Ryan M.; Miller, Mary C.; Romig-Martin, Sara A.; LaLumiere, Ryan T.

    2015-01-01

    The prelimbic region (PL) of the medial prefrontal cortex (mPFC) is implicated in the relapse of drug-seeking behavior. Optimal mPFC functioning relies on synaptic connections involving dendritic spines in pyramidal neurons, whereas prefrontal dysfunction resulting from elevated glucocorticoids, stress, aging, and mental illness are each linked to decreased apical dendritic branching and spine density in pyramidal neurons in these cortical fields. The fact that cocaine use induces activation of the stress-responsive hypothalamo-pituitary-adrenal axis raises the possibility that cocaine-related impairments in mPFC functioning may be manifested by similar changes in neuronal architecture in mPFC. Nevertheless, previous studies have generally identified increases, rather than decreases, in structural plasticity in mPFC after cocaine self-administration. Here, we use 3D imaging and analysis of dendritic spine morphometry to show that chronic cocaine self-administration leads to mild decreases of apical dendritic branching, prominent dendritic spine attrition in PL pyramidal neurons, and working memory deficits. Importantly, these impairments were largely accounted for in groups of rats that self-administered cocaine compared with yoked-cocaine- and saline-matched counterparts. Follow-up experiments failed to demonstrate any effects of either experimenter-administered cocaine or food self-administration on structural alterations in PL neurons. Finally, we verified that the cocaine self-administration group was distinguished by more protracted increases in adrenocortical activity compared with yoked-cocaine- and saline-matched controls. These studies suggest a mechanism whereby increased adrenocortical activity resulting from chronic cocaine self-administration may contribute to regressive prefrontal structural and functional plasticity. SIGNIFICANCE STATEMENT Stress, aging, and mental illness are each linked to decreased prefrontal plasticity. Here, we show that chronic

  19. Cocaine withdrawal

    Science.gov (United States)

    ... feeling of discomfort Increased appetite Vivid and unpleasant dreams Slowing of activity The craving and depression can ... powerful. Exams and Tests A physical examination and history of cocaine use are often all that is ...

  20. Cocaine intoxication

    Science.gov (United States)

    ... with other substances, which can cause additional symptoms. Exams and Tests Tests may include: Blood chemistries and ... ECG) References Perrone J, Hoffman RS. Cocaine, amphetamines, caffeine, and nicotine. In: Tintinalli JE, Kelen GD, Stapczynski ...

  1. Reinforcing Effects Of Compounds Lacking Intrinsic Efficacy At α1 Subunit-Containing GABAA Receptor Subtypes in Midazolam- But Not Cocaine-Experienced Rhesus Monkeys

    Science.gov (United States)

    Shinday, Nina M; Sawyer, Eileen K; Fischer, Bradford D; Platt, Donna M; Licata, Stephanie C; Atack, John R; Dawson, Gerard R; Reynolds, David S; Rowlett, James K

    2013-01-01

    Benzodiazepines are prescribed widely but their utility is limited by unwanted side effects, including abuse potential. The mechanisms underlying the abuse-related effects of benzodiazepines are not well understood, although α1 subunit-containing GABAA receptors have been proposed to have a critical role. Here, we examine the reinforcing effects of several compounds that vary with respect to intrinsic efficacy at α2, α3, and α5 subunit-containing GABAA receptors but lack efficacy at α1 subunit-containing GABAA receptors (‘α1-sparing compounds'): MRK-623 (functional selectivity for α2/α3 subunit-containing receptors), TPA023B (functional selectivity for α2/α3/α5 subunit-containing receptors), and TP003 (functional selectivity for α3 subunit-containing receptors). The reinforcing effects of the α1-sparing compounds were compared with those of the non-selective benzodiazepine receptor partial agonist MRK-696, and non-selective benzodiazepine receptor full agonists, midazolam and lorazepam, in rhesus monkeys trained to self-administer midazolam or cocaine, under a progressive-ratio schedule of intravenous (i.v.) drug injection. The α1-sparing compounds were self-administered significantly above vehicle levels in monkeys maintained under a midazolam baseline, but not under a cocaine baseline over the dose ranges tested. Importantly, TP003 had significant reinforcing effects, albeit at lower levels of self-administration than non-selective benzodiazepine receptor agonists. Together, these results suggest that α1 subunit-containing GABAA receptors may have a role in the reinforcing effects of benzodiazepine-type compounds in monkeys with a history of stimulant self-administration, whereas α3 subunit-containing GABAA receptors may be important mediators of the reinforcing effects of benzodiazepine-type compounds in animals with a history of sedative-anxiolytic/benzodiazepine self-administration. PMID:23303046

  2. Animal models of social contact and drug self-administration.

    Science.gov (United States)

    Strickland, Justin C; Smith, Mark A

    2015-09-01

    Social learning theories of drug abuse propose that individuals imitate drug use behaviors modeled by social peers, and that these behaviors are selectively reinforced and/or punished depending on group norms. Historically, animal models of social influence have focused on distal factors (i.e., those factors outside the drug-taking context) in drug self-administration studies. Recently, several investigators have developed novel models, or significantly modified existing models, to examine the role of proximal factors (i.e., those factors that are immediately present at the time of drug taking) on measures of drug self-administration. Studies using these newer models have revealed several important conclusions regarding the effects of social learning on drug abuse: 1) the presence of a social partner influences drug self-administration, 2) the behavior of a social partner determines whether social contact will increase or decrease drug intake, and 3) social partners can model and imitate specific patterns of drug self-administration. These findings are congruent with those obtained in the human laboratory, providing support for the cross-species generality and validity of these preclinical models. This mini-review describes in detail some of the preclinical animal models used to study social contact and drug self-administration to guide future research on social learning and drug abuse.

  3. Effects of caffeine on alcohol consumption and nicotine self-administration in rats.

    Science.gov (United States)

    Rezvani, Amir H; Sexton, Hannah G; Johnson, Joshua; Wells, Cori; Gordon, Karen; Levin, Edward D

    2013-09-01

    Caffeine, alcohol, and nicotine are 3 of the most widespread self-administered psychoactive substances, which are known to be extensively co-administered. However, little is known about the degree to which they may mutually potentiate each other's consumption. In the current set of studies, we examined in rats the effect of caffeine administration on alcohol drinking and intravenous (i.v.) self-administration of nicotine. In male alcohol-preferring (P) rats, caffeine (5, 10, and 20 mg/kg) or the saline vehicle was administered acutely either by subcutaneous (S.C.) injection or orally (PO) by gavage. In a chronic study, the effect of PO caffeine (5 and 20 mg/kg) on alcohol intake over a 10-day period was tested. In another experiment, the effect of acute PO administration of caffeine (20 mg/kg) or saline on saccharin intake (0.2% solution) was determined in P rats. Effects of 20 mg/kg caffeine on motor activity were also determined in P rats. Finally, the effects of acute PO caffeine administration on nicotine self-administration in Sprague-Dawley rats were also determined. Both routes of administration of caffeine, S.C. and PO, caused a significant dose-related decrease in alcohol intake and preference during free access to alcohol and after 4-day deprivation of alcohol. However, the low dose of 5 mg/kg caffeine increased alcohol intake. Acute PO caffeine also reduced saccharin intake. Acute systemic administration of 20 mg/kg caffeine did not exert a significant effect on motor activity. In Sprague-Dawley rats trained to self-administer i.v. nicotine, acute PO administration of caffeine significantly increased self-administration of nicotine in a dose-related manner. These results suggest that adenosine receptor systems may play a role in both alcohol and nicotine intake and deserve further study regarding these addictions. Copyright © 2013 by the Research Society on Alcoholism.

  4. Beer self-administration provokes lateralized nucleus accumbens dopamine release in male heavy drinkers.

    Science.gov (United States)

    Oberlin, Brandon G; Dzemidzic, Mario; Tran, Stella M; Soeurt, Christina M; O'Connor, Sean J; Yoder, Karmen K; Kareken, David A

    2015-03-01

    Although striatal dopamine (DA) is important in alcohol abuse, the nature of DA release during actual alcohol drinking is unclear, since drinking includes self-administration of both conditioned flavor stimuli (CS) of the alcoholic beverage and subsequent intoxication, the unconditioned stimulus (US). Here, we used a novel self-administration analog to distinguish nucleus accumbens (NAcc) DA responses specific to the CS and US. Right-handed male heavy drinkers (n = 26) received three positron emission tomography (PET) scans with the D2/D3 radioligand [(11)C]raclopride (RAC) and performed a pseudo self-administration task that separately administered a flavor CS of either a habitually consumed beer or the appetitive control Gatorade®, concomitant with the US of ethanol intoxication (0.06 g/dL intravenous (IV) administration) or IV saline. Scan conditions were Gatorade flavor + saline (Gat&Sal), Gatorade flavor + ethanol (Gat&Eth), and beer flavor + ethanol (Beer&Eth). Ethanol (US) reduced RAC binding (inferring DA release) in the left (L) NAcc [Gat&Sal > Gat&Eth]. Beer flavor (CS) increased DA in the right (R) NAcc [Gat&Eth > Beer&Eth]. The combination of beer flavor and ethanol (CS + US), [Gat&Sal > Beer&Eth], induced DA release in bilateral NAcc. Self-reported intoxication during scanning correlated with L NAcc DA release. Relative to saline, infusion of ethanol increased alcoholic drink wanting. Our findings suggest lateralized DA function in the NAcc, with L NAcc DA release most reflecting intoxication, R NAcc DA release most reflecting the flavor CS, and the conjoint CS + US producing a bilateral NAcc response.

  5. Effects of Caffeine on Alcohol Consumption and Nicotine Self-Administration in Rats

    Science.gov (United States)

    Rezvani, Amir H.; Sexton, Hannah G.; Johnson, Joshua; Wells, Cori; Gordon, Karen; Levin, Edward D.

    2013-01-01

    Background Caffeine, alcohol and nicotine are three of the most widespread self-administered psychoactive substances, which are known to be extensively co-administered. However, little is known about the degree to which they may mutually potentiate each other’s consumption. Methods In the current set of studies, we examined in rats the effect of caffeine administration on alcohol drinking and intravenous (i.v.) self-administration of nicotine. In male alcohol-preferring P rats, caffeine (5, 10 and 20 mg/kg) or the saline vehicle was administered acutely either by subcutaneous (S.C.) injection or orally (PO) by gavage. In a chronic study, the effect of oral caffeine (5 and 20 mg/kg) on alcohol intake over a 10-day period was tested. In another experiment, the effect of acute oral administration of caffeine (20 mg/kg) or saline on saccharin intake (0.2% solution) was determined in P rats. Effects of 20 mg/kg caffeine on motor activity were also determined in P rats. Finally, the effects of acute oral caffeine administration on nicotine self-administration in Sprague-Dawley rats were also determined. Results Both routes of administration of caffeine, S.C. and PO, caused a significant dose-related decrease in alcohol intake and preference during free access to alcohol and after 4-day deprivation of alcohol. However, the low dose of 5 mg/kg caffeine increased alcohol intake. Acute oral caffeine also reduced saccharin intake. Acute systemic administration of 20 mg/kg caffeine did not exert a significant effect on motor activity. In Sprague-Dawley rats trained to self-administer i.v. nicotine, acute oral administration of caffeine significantly increased self-administration of nicotine in a dose-related manner. Conclusions These results suggest that adenosine receptor systems may play a role in both alcohol and nicotine intake and deserve further study regarding these addictions. PMID:23895206

  6. Varenicline impairs extinction and enhances reinstatement across repeated cycles of nicotine self-administration in rats.

    Science.gov (United States)

    Macnamara, Claire L; Holmes, Nathan M; Westbrook, R Fred; Clemens, Kelly J

    2016-06-01

    Varenicline is a partial nicotine receptor agonist widely prescribed as a smoking cessation medication. Repeated (or long-term) use of varenicline has been proposed as a treatment option for tobacco addiction. However the effect of repeated varenicline use on motivation for nicotine is unknown. Here the intravenous nicotine self-administration paradigm in rats was used to model the consequences of varenicline treatment across repeated cycles of administration, extinction and reinstatement. Rats acquired nicotine self-administration across 20 days before undergoing 6 days of extinction, where each extinction session was preceded by a single injection of varenicline or saline. This was followed by a single varenicline-free nicotine-primed reinstatement test. All rats then reacquired nicotine self-administration for 10 days followed by a second cycle of extinction. Across this period, rats either received a second cycle of varenicline (VAR-VAR) or saline (SAL-SAL), or the alternative treatment (SAL-VAR, VAR-SAL), followed by a final reinstatement test. Treatment with varenicline increased responding across the first cycle of extinction, but did not affect responding in the reinstatement test. Across the second cycle, varenicline again increased responding across extinction, and critically, rats treated with varenicline across cycle 1 and saline across cycle 2 (Group VAR-SAL) exhibited more reinstatement than rats in any other group. The effect of VAR on nicotine seeking was not due to its effects on locomotor activity. Instead, the results suggest that a history of VAR can increase vulnerability to reinstatement/relapse when its treatment is discontinued. The possible mechanisms of this increased vulnerability are discussed.

  7. Carbon disulfide mediates socially-acquired nicotine self-administration.

    Directory of Open Access Journals (Sweden)

    Tengfei Wang

    Full Text Available The social environment plays a critical role in smoking initiation as well as relapse. We previously reported that rats acquired nicotine self-administration with an olfactogustatory cue only when another rat consuming the same cue was present during self-administration. Because carbon disulfide (CS2 mediates social learning of food preference in rodents, we hypothesized that socially acquired nicotine self-administration is also mediated by CS2. We tested this hypothesis by placing female adolescent Sprague-Dawley rats in operant chambers equipped with two lickometers. Licking on the active spout meeting a fixed-ratio 10 schedule triggered the concurrent delivery of an i.v. infusion (saline, or 30 µg/kg nicotine, free base and an appetitive olfactogustatory cue containing CS2 (0-500 ppm. Rats that self-administered nicotine with the olfactogustatory cue alone licked less on the active spout than on the inactive spout. Adding CS2 to the olfactogustatory cue reversed the preference for the spouts. The group that received 500 ppm CS2 and the olfactogustatory cue obtained a significantly greater number of nicotine infusions than other groups. After extinction training, the original self-administration context reinstated nicotine-seeking behavior in all nicotine groups. In addition, in rats that received the olfactogustatory cue and 500 ppm CS2 during SA, a social environment where the nicotine-associated olfactory cue is present, induced much stronger drug-seeking behavior compared to a social environment lacking the olfactogustatory cue. These data established that CS2 is a critical signal that mediates social learning of nicotine self-administration with olfactogustatory cues in rodents. Additionally, these data showed that the social context can further enhance the drug-seeking behavior induced by the drug-taking environment.

  8. Evaluation of WIN 55,212-2 self-administration in rats as a potential cannabinoid abuse liability model

    Science.gov (United States)

    Lefever, Timothy W.; Marusich, Julie A.; Antonazzo, Kateland R.; Wiley, Jenny L.

    2014-01-01

    Because Δ9-tetrahydrocannabinol (THC) has been a false negative in rat intravenous self-administration procedures, evaluation of the abuse potential of candidate cannabinoid medications has proved difficult. One lab group has successfully trained self-administration of the aminoalkylindole WIN55,212-2 in rats; however, their results have not been independently replicated. The purpose of this study was to extend their model by using a within-subjects design, with the goal of establishing a robust method suitable for substitution testing of other cannabinoids. Male Long-Evans rats were trained to self-administer WIN55,212-2 (0.01 mg/kg/infusion) on a fixed ratio 3 schedule. Dose-effect curves for WIN55,212-2 were determined, followed by vehicle substitution and a dose-effect curve with THC. WIN55,212-2 self-administration was acquired; however, substitution with THC did not maintain responding above vehicle levels. Dose-dependent attenuation by rimonabant confirmed CB1 receptor mediation of WIN55,212-2’s reinforcing effects. Vehicle substitution resulted in a session-dependent decrease in responding (i.e., extinction). While this study provides systematic replication of previous studies, lack of substitution with THC is problematic and suggests that WIN55,212-2 self-administration may be of limited usefulness as a screening tool for detection of the reinforcing effects of potential cannabinoid medications. Clarification of underlying factors responsible for failure of THC to maintain self-administration in cannabinoid-trained rats is needed. PMID:24412835

  9. Dopamine transporter-dependent and -independent striatal binding of the benztropine analog JHW 007, a cocaine antagonist with low abuse liability

    Science.gov (United States)

    The benztropine analog JHW 007 displays high affinity for the dopamine transporter (DAT), but unlike typical DAT ligands, has relatively low abuse liability and blocks effects of cocaine,including its self-administration. To determine sites responsible for the cocaine-antagonist effects of JHW 007, ...

  10. Mind Over Matter: Cocaine

    Science.gov (United States)

    ... Term(s): Teachers / NIDA Teaching Guide / Mind Over Matter Teaching Guide and Series / Cocaine Print Mind Over Matter: Cocaine Order Free Publication in: English Spanish Download PDF 806.08 KB Cocaine is ...

  11. Neuropeptide Y Y5 receptor antagonism attenuates cocaine-induced effects in mice

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Jensen, Morten; Weikop, Pia

    2012-01-01

    Rationale Several studies suggest a role for neuropeptide Y (NPY) in addiction to drugs of abuse, including cocaine. However, the NPY receptors mediating addiction-related effects remain to be determined. Objectives To explore the potential role of Y5 NPY receptors in cocaine-induced behavioural...... effects. Methods The Y5 antagonist L-152,804 and Y5-knockout (Y5-KO) mice were tested in two models of cocaine addiction-related behaviour: acute self-administration and cocaine-induced hyperactivity. We also studied effects of Y5 receptor antagonism on cocaine-induced c-fos expression and extracellular...... effects, suggesting that Y5 receptors could be a potential therapeutic target in cocaine addiction....

  12. Elevated dopamine in the medial prefrontal cortex suppresses cocaine seeking via D1 receptor overstimulation.

    Science.gov (United States)

    Devoto, Paola; Fattore, Liana; Antinori, Silvia; Saba, Pierluigi; Frau, Roberto; Fratta, Walter; Gessa, Gian Luigi

    2016-01-01

    Previous investigations indicate that the dopamine-β-hydroxylase (DBH) inhibitors disulfiram and nepicastat suppress cocaine-primed reinstatement of cocaine self-administration behaviour. Moreover, both inhibitors increase dopamine release in the rat medial prefrontal cortex (mPFC) and markedly potentiate cocaine-induced dopamine release in this region. This study was aimed to clarify if the suppressant effect of DBH inhibitors on cocaine reinstatement was mediated by the high extracellular dopamine in the rat mPFC leading to a supra-maximal stimulation of D1 receptors in the dorsal division of mPFC, an area critical for reinstatement of cocaine-seeking behaviour. In line with previous microdialysis studies in drug-naïve animals, both DBH inhibitors potentiated cocaine-induced dopamine release in the mPFC, in the same animals in which they also suppressed reinstatement of cocaine seeking. Similar to the DBH inhibitors, L-DOPA potentiated cocaine-induced dopamine release in the mPFC and suppressed cocaine-induced reinstatement of cocaine-seeking behaviour. The bilateral microinfusion of the D1 receptor antagonist SCH 23390 into the dorsal mPFC not only prevented cocaine-induced reinstatement of cocaine seeking but also reverted both disulfiram- and L-DOPA-induced suppression of reinstatement. Moreover, the bilateral microinfusion of the D1 receptor agonist chloro-APB (SKF 82958) into the dorsal mPFC markedly attenuated cocaine-induced reinstatement of cocaine seeking. These results suggest that stimulation of D1 receptors in the dorsal mPFC plays a crucial role in cocaine-induced reinstatement of cocaine seeking, whereas the suppressant effect of DBH inhibitors and L-DOPA on drug-induced reinstatement is mediated by a supra-maximal stimulation of D1 receptors leading to their inactivation.

  13. Cocaine, Marijuana, Hypertension and Cardiovascular Effects

    Directory of Open Access Journals (Sweden)

    Mohammad Hassan Ghadiani

    2015-07-01

    Full Text Available Cocaine is used by more than 14 million people worldwide, about 0.3 percent of the global population age is 15 to 64 years. After alcohol, cocaine is the most common cause of acute drug-related emergency department visits in the United States. Cocaine consumption is more frequently associated with acute cardiovascular illness.  Cocaine stimulates α1, α2, β1 and β2 adrenergic receptors through increased levels of norepinephrine and a lesser extent epinephrine. The cardiovascular effects of cocaine are thought to be similar and regardless to the route of consumption. An acute coronary syndrome is the most common cardiac problem including myocardial ischemia and infarction even in young persons without atherosclerosis, aortic dissection and rupture, arrhythmias, ventricular tachycardia and fibrillation, asystole and finally sudden death. Other cardiovascular effects that caused by cocaine include coronary artery aneurysm, palpitation, sinus tachycardia, increased systemic vascular resistance and hypertension crisis, left ventricular hypertrophy, myocarditis, cardiomyopathy, myocardial fibrosis, bundle branch block, heart block, supraventricular arrhythmia, accelerated atherosclerosis, hypotension, bradycardia and infective endocarditis  among intravenous users.Cocaine by three mechanisms cause ischemia: 1. increased myocardial oxygen demand, 2. decreased coronary blood flow due to coronary artery vasoconstriction and spasm and 3. Coronary artery thrombosis via activation of platelets, stimulation of platelet aggregation and potentiation of thromboxane production.

  14. Nicotine self-administration induces CB1-dependent LTP in the bed nucleus of the stria terminalis.

    Science.gov (United States)

    Reisiger, Anne-Ruth; Kaufling, Jennifer; Manzoni, Olivier; Cador, Martine; Georges, François; Caillé, Stephanie

    2014-03-19

    Nicotine addiction is characterized by repetitive drug taking and drug seeking, both tightly controlled by cannabinoid CB1 receptors. The responsiveness of neurons of the bed nucleus of the stria terminalis (BNST) to infralimbic cortex (ILCx) excitatory inputs is increased in rats with active, but not passive, nicotine taking. Therefore, we hypothesize that acquisition of the learned association between nicotine infusion and a paired cue light permits the strengthening of the ILCx-BNST synapses after ILCx tetanic stimulation. We exposed rats to intravenous nicotine self-administration for 2 months. Using a combination of in vivo protocols (electrical stimulations, extracellular recordings, and pharmacological manipulations), we characterized the effects of 10 Hz stimulation of the ILCx on BNST excitatory responses, under different conditions of exposure to nicotine. In addition, we tested whether the effects of the stimulation were CB1 receptor-dependent. The results show that nicotine self-administration supports the induction of evoked spike potentiation in the BNST in response to 10 Hz stimulation of ILCx afferents. Although not altered by nicotine abstinence, this cellular adaptation was blocked by CB1 receptor antagonism. Moreover, blockade of BNST CB1 receptors prevented increases in time-out responding subsequent to ILCx stimulation and decreased cue-induced reinstatement. Thus, the synaptic potentiation within the BNST in response to ILCx stimulation seems to contribute to the cue-elicited responding associated with nicotine self-administration and is tightly controlled by CB1 receptors.

  15. The dopamine β-hydroxylase inhibitor, nepicastat, suppresses chocolate self-administration and reinstatement of chocolate seeking in rats.

    Science.gov (United States)

    Zaru, Alessandro; Maccioni, Paola; Colombo, Giancarlo; Gessa, Gian Luigi

    2013-10-01

    Craving for chocolate is a common phenomenon, which may evolve to an addictive-like behaviour and contribute to obesity. Nepicastat is a selective dopamine β-hydroxylase (DBH) inhibitor that suppresses cocaine-primed reinstatement of cocaine seeking in rats. We verified whether nepicastat was able to modify the reinforcing and motivational properties of a chocolate solution and to prevent the reinstatement of chocolate seeking in rats. Nepicastat (25, 50 and 100 mg/kg, intraperitoneal) produced a dose-related inhibition of operant self-administration of the chocolate solution in rats under fixed-ratio 10 (FR10) and progressive-ratio schedules of reinforcement, measures of the reinforcing and motivational properties of the chocolate solution, respectively. The effect of nepicastat on the reinstatement of chocolate seeking was studied in rats in which lever-responding had been extinguished by removing the chocolate solution for approximately 8 d. Nepicastat dose-dependently suppressed the reinstatement of lever-responding triggered by a 'priming' of the chocolate solution together with cues previously associated with the availability of the reward. In a separate group of food-restricted rats trained to lever-respond for regular food pellets, nepicastat reduced FR10 lever-responding with the same potency as for the chocolate solution. Spontaneous locomotor activity was not modified by nepicastat doses that reduced self-administration of the chocolate solution and regular food pellets and suppressed the reinstatement of chocolate seeking. The results indicate that nepicastat reduces motivation to food consumption sustained by appetite or palatability. Moreover, the results suggest that DBH inhibitors may be a new class of pharmacological agents potentially useful in the prevention of relapse to food seeking in human dieters.

  16. Role for M5 muscarinic acetylcholine receptors in cocaine addiction.

    Science.gov (United States)

    Fink-Jensen, Anders; Fedorova, Irina; Wörtwein, Gitta; Woldbye, David P D; Rasmussen, Thøger; Thomsen, Morgane; Bolwig, Tom G; Knitowski, Karen M; McKinzie, David L; Yamada, Masahisa; Wess, Jürgen; Basile, Anthony

    2003-10-01

    Muscarinic cholinergic receptors of the M5 subtype are expressed by dopamine-containing neurons of the ventral tegmentum. These M5 receptors modulate the activity of midbrain dopaminergic neurons, which play an important role in mediating reinforcing properties of abused psychostimulants like cocaine. The potential role of M5 receptors in the reinforcing effects of cocaine was investigated using M5 receptor-deficient mice in a model of acute cocaine self-administration. The M5-deficient mice self-administered cocaine at a significantly lower rate than wild-type controls. In the conditioned place preference procedure, a classic test for evaluating the rewarding properties of drugs, M5-deficient mice spent significantly less time in the cocaine-paired compartment than control mice. Moreover, the severity of the cocaine withdrawal syndrome (withdrawal-associated anxiety measured in the elevated plus-maze) was significantly attenuated in mice lacking the M5 receptor. These results demonstrate that M5 receptors play an important role in mediating both cocaine-associated reinforcement and withdrawal.

  17. Laboratory alcohol self-administration experiments do not increase subsequent real-life drinking in young adult social drinkers.

    Science.gov (United States)

    Sommer, Christian; Seipt, Christian; Spreer, Maik; Blümke, Toni; Markovic, Alexandra; Jünger, Elisabeth; Plawecki, Martin H; Zimmermann, Ulrich S

    2015-06-01

    While the utility of experimental free-access alcohol self-administration paradigms is well established, little data exist addressing the question of whether study participation influences subsequent natural alcohol consumption. We here present drinking reports of young adults before and after participation in intravenous alcohol self-administration studies. Timeline Follow-back drinking reports for the 6 weeks immediately preceding the first, and the 6 weeks after the last experimental alcohol challenge were examined from subjects completing 1 of 2 similar alcohol self-administration paradigms. In study 1, 18 social drinkers (9 females, mean age 24.1 years) participated in 3 alcohol self-infusion sessions up to a maximum blood alcohol concentration (BAC) of 160 mg%. Study 2 involved 60 participants (30 females, mean age 18.3 years) of the Dresden Longitudinal Study on Alcohol Use in Young Adults (D-LAYA), who participated in 2 sessions of alcohol self-infusion up to a maximum BAC of 120 mg%, and a nonexposed age-matched control group of 42 (28 females, mean age 18.4 years) subjects. In study 1, participants reported (3.7%) fewer heavy drinking days as well as a decrease of 2.5 drinks per drinking day after study participation compared to prestudy levels (p alcohol-exposed participants reported 7.1% and non-alcohol-exposed controls 6.5% fewer drinking days at poststudy measurement (p alcohol self-administration experiments does not increase subsequent real-life drinking of young adults. Copyright © 2015 by the Research Society on Alcoholism.

  18. Cocaine. Specialized Information Service.

    Science.gov (United States)

    Do It Now Foundation, Phoenix, AZ.

    This compilation of journal articles on cocaine includes a report describing cocaine as the recreational drug of the middle class, statistics from the United States Department of Health on health consequences of cocaine use, an article on "speedballing" (use of cocaine and heroin in combination), and a discussion of the various ways…

  19. Improvements in self-administration studies based on changes in skin button type and surgical technique.

    Science.gov (United States)

    Gilbert, Lindsey M; Sgro, Mario P; Modlin, Deah L; Wheat, Nathaniel J; Kallman, Mary J

    2015-01-01

    These studies, ranging in duration from 3 to 8months, evaluated the patency and longevity of the intravenous (IV) self-administration surgical model in male Sprague Dawley rats. Surgeries were categorized and assessed based on the number of catheter and/or skin button repairs required per animal across four separate self-administration studies. Design improvements in skin button types and changes in surgical procedures were chronologically tracked and assessed. Animals were evaluated under a self-administration paradigm in which they were trained to respond for a food reward under a fixed ratio schedule (FR5 or FR10). Animals were then surgically prepared with a femoral catheter and skin button port. Following recovery, animals were returned to food-maintained responding for at least 5 sessions and subsequently trained to respond for injections of a reinforcing drug. Once drug training criteria was established, the effects of vehicle or varying doses of test articles were evaluated. Animals were tested in operant chambers one hour each day 5days a week and the length of each study was recorded. Differences in the number of repairs per study as well as the total number of repairs were tabulated. Study length was directly correlated to the mean number of repairs occurring per study, with study length increasing as the total number of repairs increased. The majority of repairs were skin button-related issues. Multiple combinations of skin button types and surgical techniques were implemented across time to evaluate model efficiency and decrease overall cycle time per study. Initial combinations produced a greater number of repairs on a per study basis. However, the skin button type and surgical technique combination that resulted in the fewest number of total repairs used a lateral incision with a dorsal biopsy punch. The combination of improvements in skin button type and surgical techniques drastically decreased the number of surgical repairs required per study

  20. Mapping cocaine binding sites in human and baboon brain in vivo.

    Science.gov (United States)

    Fowler, J S; Volkow, N D; Wolf, A P; Dewey, S L; Schlyer, D J; Macgregor, R R; Hitzemann, R; Logan, J; Bendriem, B; Gatley, S J

    1989-01-01

    The first direct measurements of cocaine binding in the brain of normal human volunteers and baboons have been made by using positron emission tomography (PET) and tracer doses of [N-11C-methyl]-(-)-cocaine ([11C]cocaine). Cocaine's binding and release from brain are rapid with the highest regional uptake of carbon-11 occurring in the corpus striatum at 4-10 minutes after intravenous injection of labeled cocaine. This was followed by a clearance to half the peak value at about 25 minutes with the overall time course paralleling the previously documented time course of the euphoria experienced after intravenous cocaine administration. Blockade of the dopamine reuptake sites with nomifensine reduced the striatal but not the cerebellar uptake of [11C]cocaine in baboons indicating that cocaine binding is associated with the dopamine reuptake site in the corpus striatum. A comparison of labeled metabolites of cocaine in human and baboon plasma showed that while cocaine is rapidly metabolized in both species, the profile of labeled metabolites is different, with baboon plasma containing significant amounts of labeled carbon dioxide, and human plasma containing no significant labeled carbon dioxide. These studies demonstrate the feasibility of using [11C]cocaine and PET to map binding sites for cocaine in human brain, to monitor its kinetics, and to characterize its binding mechanism by using appropriate pharmacological challenges.

  1. Cocaine serves as a peripheral interoceptive conditioned stimulus for central glutamate and dopamine release.

    Directory of Open Access Journals (Sweden)

    Roy A Wise

    Full Text Available Intravenous injections of cocaine HCl are habit-forming because, among their many actions, they elevate extracellular dopamine levels in the terminal fields of the mesocorticolimbic dopamine system. This action, thought to be very important for cocaine's strong addiction liability, is believed to have very short latency and is assumed to reflect rapid brain entry and pharmacokinetics of the drug. However, while intravenous cocaine HCl has almost immediate effects on behavior and extracellular dopamine levels, recent evidence suggests that its central pharmacological effects are not evident until 10 or more seconds after IV injection. Thus the immediate effects of a given intravenous cocaine injection on extracellular dopamine concentration and behavior appear to occur before there is sufficient time for cocaine to act centrally as a dopamine uptake inhibitor. To explore the contribution of peripheral effects of cocaine to the early activation of the dopamine system, we used brain microdialysis to measure the effects of cocaine methiodide (MI--a cocaine analogue that does not cross the blood brain barrier--on glutamate (excitatory input to the dopamine cells. IP injections of cocaine MI were ineffective in cocaine-naïve animals but stimulated ventral tegmental glutamate release in rats previously trained to lever-press for cocaine HCl. This peripherally triggered glutamate input was sufficient to reinstate cocaine-seeking in previously trained animals that had undergone extinction of the habit. These findings offer an explanation for short-latency behavioral responses and immediate dopamine elevations seen following cocaine injections in cocaine-experienced but not cocaine-naïve animals.

  2. Reinstatement in a Cocaine vs. Food Choice Situation: Reversal of Preference between Drug and Non-Drug Rewards

    Science.gov (United States)

    Tunstall, Brendan J.; Kearns, David N.

    2013-01-01

    Recent studies (for review see Ahmed, 2010; 2012) show that when given a mutually exclusive choice between cocaine and food, rats almost exclusively choose food. The present experiment investigated potential shifts in preference between levers associated with either food or cocaine which might occur during extinction (food and cocaine no longer available) and during footshock-induced, cocaine-primed, and food-primed reinstatement. During self-administration sessions where food and cocaine were simultaneously available, rats demonstrated a stable food preference, choosing food over cocaine on 83% of trials. During extinction when neither reinforcer was available, no preference between levers was evident and responding decreased until rats responded on the previously food- and cocaine-associated levers at equally low rates. Footshock resulted in a non-specific reinstatement of responding upon both levers, while cocaine priming resulted in a significant preference for cocaine seeking over food seeking. This suggests that the mechanism underlying footshock-induced reinstatement is distinct from that of cocaine-primed reinstatement. Food priming engendered a mild, non-specific increase in responding on both levers. Although rats generally prefer food over cocaine when presented with a choice between these primary reinforcers, the present results suggest that in certain situations cocaine-seeking behavior prevails over food-seeking behavior. PMID:23551949

  3. Reinstatement in a cocaine versus food choice situation: reversal of preference between drug and non-drug rewards.

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    Tunstall, Brendan J; Kearns, David N

    2014-09-01

    Recent studies show that when given a mutually exclusive choice between cocaine and food, rats almost exclusively choose food. The present experiment investigated potential shifts in preference between levers associated with either food or cocaine that might occur during extinction (food and cocaine no longer available) and during footshock-induced, cocaine-primed and food-primed reinstatement. During self-administration sessions where food and cocaine were simultaneously available, rats demonstrated a stable food preference, choosing food over cocaine on 83% of trials. During extinction when neither reinforcer was available, no preference between levers was evident and responding decreased until rats responded on the previously food- and cocaine-associated levers at equally low rates. Footshock resulted in a non-specific reinstatement of responding upon both levers, while cocaine priming resulted in a significant preference for cocaine seeking over food seeking. This suggests that the mechanism underlying footshock-induced reinstatement is distinct from that of cocaine-primed reinstatement. Food priming engendered a mild, non-specific increase in responding on both levers. Although rats generally prefer food over cocaine when presented with a choice between these primary reinforcers, the present results suggest that in certain situations, cocaine-seeking behavior prevails over food-seeking behavior. © 2013 Society for the Study of Addiction.

  4. Cocaine-seeking behavior in a genetic model of attention-deficit/hyperactivity disorder following adolescent methylphenidate or atomoxetine treatments.

    Science.gov (United States)

    Jordan, Chloe J; Harvey, Roxann C; Baskin, Britahny B; Dwoskin, Linda P; Kantak, Kathleen M

    2014-07-01

    Attention-deficit/hyperactivity disorder (ADHD) is often comorbid with cocaine abuse. Controversy exists regarding long-term consequences of ADHD medications on cocaine abuse liability. Whereas childhood methylphenidate treatment may be preventative, methylphenidate in teens appears to further increase later cocaine abuse risk. In rodents, adolescent methylphenidate treatment further increases adult cocaine self-administration in the Spontaneously Hypertensive Rat (SHR) model of ADHD, whereas adolescent atomoxetine treatment does not. Effects of ADHD medications on cocaine cue reactivity, a critical component of addiction, are unknown. To investigate this, SHR, Wistar-Kyoto (inbred control) and Wistar (outbred control) rats received therapeutically relevant doses of methylphenidate (1.5 mg/kg, oral) and atomoxetine (0.3 mg/kg, intraperitoneal), or respective vehicles from post-natal day 28-55. Cocaine seeking, reflecting cue reactivity, was measured in adulthood during self-administration maintenance and cue-induced reinstatement tests conducted under a second-order schedule. Compared to control strains, SHR earned more cocaine infusions, emitted more cocaine-seeking responses during maintenance and reinstatement testing, and required more sessions to reach the extinction criterion. Compared to vehicle, adolescent methylphenidate, but not atomoxetine, further increased cocaine intake during maintenance testing in SHR. Adolescent atomoxetine, but not methylphenidate, decreased cocaine seeking during reinstatement testing in SHR. Neither medication had effects on cocaine intake or cue reactivity in control strains. The SHR successfully model ADHD and cocaine abuse comorbidity and show differential effects of adolescent ADHD medications on cocaine intake and cue reactivity during adulthood. Thus, SHR have heuristic value for assessing neurobiology underlying the ADHD phenotype and for evaluating pharmacotherapeutics for ADHD. Copyright © 2014 Elsevier Ireland Ltd

  5. Cocaine-seeking behavior in a genetic model of attention-deficit/hyperactivity disorder following adolescent methylphenidate or atomoxetine treatments*

    Science.gov (United States)

    Jordan, Chloe J.; Harvey, Roxann C.; Baskin, Britahny B.; Dwoskin, Linda P.; Kantak, Kathleen M.

    2014-01-01

    Background Attention-deficit/hyperactivity disorder (ADHD) is often comorbid with cocaine abuse. Controversy exists regarding long-term consequences of ADHD medications on cocaine abuse liability. Whereas childhood methylphenidate treatment may be preventative, methylphenidate in teens appears to further increase later cocaine abuse risk. In rodents, adolescent methylphenidate treatment further increases adult cocaine self-administration in the Spontaneously Hypertensive Rat (SHR) model of ADHD, whereas adolescent atomoxetine treatment does not. Effects of ADHD medications on cocaine cue reactivity, a critical component of addiction, are unknown. Methods To investigate this, SHR, Wistar-Kyoto (inbred control) and Wistar (outbred control) rats received therapeutically relevant doses of methylphenidate (1.5 mg/kg, oral) and atomoxetine (0.3 mg/kg, intraperitoneal), or respective vehicles from post-natal day 28–55. Cocaine seeking, reflecting cue reactivity, was measured in adulthood during self-administration maintenance and cue-induced reinstatement tests conducted under a second-order schedule. Results Compared to control strains, SHR earned more cocaine infusions, emitted more cocaine-seeking responses during maintenance and reinstatement testing, and required more sessions to reach the extinction criterion. Compared to vehicle, adolescent methylphenidate, but not atomoxetine, further increased cocaine intake during maintenance testing in SHR. Adolescent atomoxetine, but not methylphenidate, decreased cocaine seeking during reinstatement testing in SHR. Neither medication had effects on cocaine intake or cue reactivity in control strains. Conclusions The SHR successfully model ADHD and cocaine abuse comorbidity and show differential effects of adolescent ADHD medications on cocaine intake and cue reactivity during adulthood. Thus, SHR have heuristic value for assessing neurobiology underlying the ADHD phenotype and for evaluating pharmacotherapeutics for ADHD

  6. Selegiline modifies the extinction of responding following morphine self-administration, but does not alter cue-induced reinstatement, reacquisition of morphine reinforcement, or precipitated withdrawal.

    Science.gov (United States)

    Grasing, Kenneth; He, Shaunteng; Li, Ning

    2005-01-01

    Selegiline is an irreversible inhibitor of monoamine oxidase (MAO) with psychostimulant and neuroprotective effects which can prevent decreases in dopamine efflux that follow opiate withdrawal. The present study evaluated effects of selegiline treatment on morphine-seeking behavior and morphine reinforcement in Wistar rats (n = 26). In additional animals (n = 30), the ability of single doses of selegiline to modify naloxone-precipitated withdrawal was determined. After pretreatment with noncontingent morphine to establish opiate dependence, rats acquired self-administration of intravenous morphine. Daily intravenous treatment with saline or 2.0mg kg(-1) doses of selegiline was then initiated and continued over 14 days during extinction, reinstatement, and reacquisition of morphine self-administration. To reduce the potential for psychostimulant effects, selegiline was administered approximately 1h following self-administration, extinction, or reinstatement sessions. In some animals (n = 23), effects of saline or selegiline administration on locomotor activity were determined following extinction sessions. Daily selegiline treatment decreased the number of ratios completed and increased response latency during extinction, without modifying these measures during reinstatement or reacquisition of morphine self-administration. Chronic selegiline treatment increased locomotor activity recorded between 4 and 7h after selegiline administration on day 7 of extinction, but otherwise did not alter locomotor activity. Pretreatment with single, 2.0mg kg(-1) doses of selegiline did not modify naloxone-precipitated withdrawal. In conclusion, pretreatment with selegiline produced only a small decrease in responding during extinction of morphine self-administration and did not modify cue-induced reinstatement of morphine-seeking behavior, reacquisition or morphine reinforcement, or precipitated withdrawal.

  7. Preclinical Assessment of Lisdexamfetamine as an Agonist Medication Candidate for Cocaine Addiction: Effects in Rhesus Monkeys Trained to Discriminate Cocaine or to Self-Administer Cocaine in a Cocaine Versus Food Choice Procedure.

    Science.gov (United States)

    Banks, Matthew L; Hutsell, Blake A; Blough, Bruce E; Poklis, Justin L; Negus, S Stevens

    2015-01-24

    Chronic amphetamine treatment decreases cocaine consumption in preclinical and human laboratory studies and in clinical trials. Lisdexamfetamine is an amphetamine prodrug in which L-lysine is conjugated to the terminal nitrogen of d-amphetamine. Prodrugs may be advantageous relative to their active metabolites due to slower onsets and longer durations of action; however, lisdexamfetamine treatment's efficacy in decreasing cocaine consumption is unknown. This study compared lisdexamfetamine and d-amphetamine effects in rhesus monkeys using two behavioral procedures: (1) a cocaine discrimination procedure (training dose = 0.32mg/kg cocaine, i.m.); and (2) a cocaine-versus-food choice self-administration procedure. In the cocaine-discrimination procedure, lisdexamfetamine (0.32-3.2mg/kg, i.m.) substituted for cocaine with lower potency, slower onset, and longer duration of action than d-amphetamine (0.032-0.32mg/kg, i.m.). Consistent with the function of lisdexamfetamine as an inactive prodrug for amphetamine, the time course of lisdexamfetamine effects was related to d-amphetamine plasma levels by a counter-clockwise hysteresis loop. In the choice procedure, cocaine (0-0.1mg/kg/injection, i.v.) and food (1g banana-flavored pellets) were concurrently available, and cocaine maintained a dose-dependent increase in cocaine choice under baseline conditions. Treatment for 7 consecutive days with lisdexamfetamine (0.32-3.2mg/kg/day, i.m.) or d-amphetamine (0.032-0.1mg/kg/h, i.v.) produced similar dose-dependent rightward shifts in cocaine dose-effect curves and decreases in preference for 0.032mg/kg/injection cocaine. Lisdexamfetamine has a slower onset and longer duration of action than amphetamine but retains amphetamine's efficacy to reduce the choice of cocaine in rhesus monkeys. These results support further consideration of lisdexamfetamine as an agonist-based medication candidate for cocaine addiction. © The Author 2015. Published by Oxford University Press on

  8. Lesions of the oral mucosa in cocaine users who apply the drug topically.

    Science.gov (United States)

    Gandara-Rey, J M; Diniz-Freitas, M; Gandara-Vila, P; Blanco-Carrion, A; Garcia-Garcia, A

    2002-01-01

    The use and abuse of cocaine is increasingly frequent in many countries, and the associated problems are increasingly evident. The effects of cocaine in the oral cavity vary depending on the form used and the route of self-administration. In the present study we describe the lesions observed in four patients with a history of topical self-application of cocaine to the oral and/or nasal mucosa, with the aim of relieving pain produced by cocaine-induced cluster headache. In three of the four patients this practice has led to erythematous lesions, while the remaining patient showed gingival recession and bone sequestration. These lesions can probably be attributed to the vasoconstrictor activity of cocaine, and to its caustic effects on the mucosa.

  9. Comparing rewarding and reinforcing properties between 'bath salt' 3,4-methylenedioxypyrovalerone (MDPV) and cocaine using ultrasonic vocalizations in rats.

    Science.gov (United States)

    Simmons, Steven J; Gregg, Ryan A; Tran, Fionya H; Mo, Lili; von Weltin, Eva; Barker, David J; Gentile, Taylor A; Watterson, Lucas R; Rawls, Scott M; Muschamp, John W

    2016-12-01

    Abuse of synthetic psychostimulants like synthetic cathinones has risen in recent years. 3,4-Methylenedioxypyrovalerone (MDPV) is one such synthetic cathinone that demonstrates a mechanism of action similar to cocaine. Compared to cocaine, MDPV is more potent at blocking dopamine and norepinephrine reuptake and is readily self-administered by rodents. The present study compared the rewarding and reinforcing properties of MDPV and cocaine using systemic injection dose-response and self-administration models. Fifty kilohertz ultrasonic vocalizations (USVs) were recorded as an index of positive affect throughout experiments. In Experiment 1, MDPV and cocaine dose-dependently elicited 50-kHz USVs upon systemic injection, but MDPV increased USVs at greater rates and with greater persistence relative to cocaine. In Experiment 2, latency to begin MDPV self-administration was shorter than latency to begin cocaine self-administration, and self-administered MDPV elicited greater and more persistent rates of 50-kHz USVs versus cocaine. MDPV-elicited 50-kHz USVs were sustained over the course of drug load-up whereas cocaine-elicited USVs waned following initial infusions. Notably, we observed a robust presence of context-elicited 50-kHz USVs from both MDPV and cocaine self-administering rats. Collectively, these data suggest that MDPV has powerfully rewarding and reinforcing effects relative to cocaine at one-tenth doses. Consistent with prior work, we additionally interpret these data in supporting that MDPV has significant abuse risk based on its potency and subjectively positive effects. Future studies will be needed to better refine therapeutic strategies targeted at reducing the rewarding effects of cathinone analogs in efforts to ultimately reduce abuse liability. © 2016 Society for the Study of Addiction.

  10. Effects of contingent and non-contingent cocaine on drug-seeking behavior measured using a second-order schedule of cocaine reinforcement in rats.

    Science.gov (United States)

    Markou, A; Arroyo, M; Everitt, B J

    1999-06-01

    Rats were trained to respond with intravenous cocaine as the reinforcer under a fixed interval 15-min schedule, during which conditioned stimuli paired with cocaine were presented contingent on completion of a fixed ratio of 10 responses (i.e., second-order schedule of reinforcement). The effects of contingent and noncontingent cocaine were investigated. The results show that pretreatment with noncontingent (i.e., experimenter-administered) cocaine led to a satiation-like effect that was reflected in decreased numbers of responses and a tendency for an increased latency to initiate responding when the doses of cocaine administered were similar to or higher than the training/maintenance dose of cocaine. By contrast, noncontingent administration of cocaine doses lower than the training/maintenance dose, and response-contingent cocaine administration, led to increased drug-seeking behavior, as reflected in increased numbers of responses. The present data indicate that at least two factors determine whether administration of cocaine would lead to drug-seeking behavior: whether the cocaine administration is contingent or noncontingent, and the relative magnitude of the cocaine dose administered in relation to the training/maintenance dose of cocaine.

  11. Cocaine-induced psychotic disorders: presentation, mechanism, and management.

    Science.gov (United States)

    Tang, Yilang; Martin, Nancy L; Cotes, Robert O

    2014-01-01

    Cocaine, the third mostly commonly used illicit drug in the United States, has a wide range of neuropsychiatric effects, including transient psychotic symptoms. When psychotic symptoms occur within a month of cocaine intoxication or withdrawal, the diagnosis is cocaine-induced psychotic disorder (CIPD). Current evidence suggests those with CIPD are likely to be male, have longer severity and duration of cocaine use, use intravenous cocaine, and have a lower body mass index. Differentiating CIPD from a primary psychotic disorder requires a detailed history of psychotic symptoms in relation to substance use and often a longitudinal assessment. Treatment includes providing a safe environment, managing agitation and psychosis, and addressing the underlying substance use disorder. This review begins with a clinical case and summarizes the literature on CIPD, including clinical presentation, differential diagnosis, mechanism and predictors of illness, and treatment.

  12. Diazepam promotes choice of abstinence in cocaine self-administering rats.

    Science.gov (United States)

    Augier, Eric; Vouillac, Caroline; Ahmed, Serge H

    2012-03-01

    When facing a choice between cocaine and a potent, albeit inessential, non-drug alternative (i.e. water sweetened with saccharin), most cocaine self-administering rats abstain from cocaine in favor of the non-drug pursuit, regardless of the dose available and even after extended drug use. Only a minority continues to take the drug despite the opportunity of making a different choice and increasing stakes. This pattern of individual variation could suggest that the majority of rats are resilient to addiction, taking cocaine by default of other options. Only a minority would be vulnerable to addiction. This study tested the hypothesis that rats choose to refrain from cocaine self-administration because cocaine would be conflictual, having both rewarding and anxiogenic properties. Contrary to this hypothesis, however, we report here that diazepam-a broad-spectrum benzodiazepine anxiolytic-did not decrease, but instead, further increased cocaine abstinence. Interestingly, although diazepam decreased locomotion, rats adapted to this effect by spending more time near the lever associated with the preferred reward, a behavior that minimized the need for locomotion at the moment of choice. When responding for cocaine or saccharin was analyzed separately, we found that diazepam decreased responding for cocaine without affecting responding for saccharin. Finally, the abstinence-promoting effects of diazepam were also induced in cocaine-preferring rats treated chronically with diazepam. Overall, this study demonstrates that abstinence from cocaine cannot be explained away by the anxiogenic effects of cocaine, thereby reinforcing the notion of resilience to addiction. It also supports the use of benzodiazepines in the treatment of cocaine addiction.

  13. Effects of monoamine releasers with varying selectivity for releasing dopamine/norepinephrine versus serotonin on choice between cocaine and food in rhesus monkeys.

    Science.gov (United States)

    Banks, Matthew L; Blough, Bruce E; Negus, S Stevens

    2011-12-01

    Monoamine releasers constitute one class of candidate medications for the treatment of cocaine abuse, and concurrent cocaine-versus-food choice procedures are potentially valuable as experimental tools to evaluate the efficacy and safety of candidate medications. This study assessed the choice between cocaine and food by rhesus monkeys during treatment with five monoamine releasers that varied in selectivity to promote the release of dopamine and norepinephrine versus serotonin (5HT) [m-fluoroamphetamine, (+)-phenmetrazine, (+)-methamphetamine, napthylisopropylamine and (±)-fenfluramine]. Rhesus monkeys (n=8) responded under a concurrent-choice schedule of food delivery (1-g pellets, fixed ratio 100 schedule) and cocaine injections (0-0.1 mg/kg/injection, fixed ratio 10 schedule). Cocaine choice dose-effect curves were determined daily during continuous 7-day treatment with saline or with each test compound dose. During saline treatment, cocaine maintained a dose-dependent increase in cocaine choice, and the highest cocaine doses (0.032-0.1 mg/kg/injection) maintained almost exclusive cocaine choice. Efficacy of monoamine releasers to decrease cocaine choice corresponded to their pharmacological selectivity to release dopamine and norepinephrine versus 5HT. None of the releasers reduced cocaine choice or promoted reallocation of responding to food choice to the same extent as when saline was substituted for cocaine. These results extend the range of conditions across which dopamine and norepinephrine-selective releasers have been shown to reduce cocaine self-administration.

  14. Inhibition of histone deacetylases facilitates extinction and attenuates reinstatement of nicotine self-administration in rats.

    Directory of Open Access Journals (Sweden)

    Matthew R Castino

    Full Text Available Chromatin remodelling is integral to the formation of long-term memories. Recent evidence suggests that histone modification may play a role in the persistence of memories associated with drug use. The present series of experiments aimed to examine the effect of histone deacetylase (HDAC inhibition on the extinction and reinstatement of nicotine self-administration. Rats were trained to intravenously self-administer nicotine for 12 days on a fixed-ratio 1 schedule. In Experiment 1, responding was then extinguished through removal of nicotine and response-contingent cues. After each extinction session, the HDAC inhibitor, sodium butyrate (NaB, was administered immediately, or six hours after each session. In Experiment 2, response-contingent cues remained available across extinction to increase rates of responding during this phase, and NaB was administered immediately after the session. Finally, in Experiment 3, the effect of NaB treatment on extinction of responding for sucrose pellets was assessed. Across all experiments reinstatement to the cue and/or the reward itself was then tested. In the first experiment, treatment with NaB significantly attenuated nicotine and nicotine + cue reinstatement when administered immediately, but not six hours after each extinction session. When administered after cue-extinction (Expt. 2, NaB treatment specifically facilitated the rate of extinction across sessions, indicating that HDAC inhibition enhanced consolidation of the extinction memory. In contrast, there was no effect of NaB on the extinction and reinstatement of sucrose-seeking (Expt. 3, indicating that the observed effects are specific to a drug context. These results provide the first demonstration that HDAC inhibition facilitates the extinction of responding for an intravenously self-administered drug of abuse and further highlight the potential of HDAC inhibitors in the treatment of drug addiction.

  15. The effects of varenicline on methamphetamine self-administration and drug-primed reinstatement in female rats

    Science.gov (United States)

    Pittenger, Steven T.; Barrett, Scott T.; Chou, Shinnyi; Bevins, Rick A.

    2015-01-01

    While research has revealed heightened vulnerability to meth addiction in women, preclinical models rarely use female subjects when investigating meth seeking and relapse. The goal of the present study was to examine the effects of varenicline (Chantix®), a partial α4β2 and full α7 nicotinic acetylcholine receptor agonist, on meth self-administration and reinstatement in female rats. Sprague-Dawley rats were surgically implanted with an indwelling jugular catheter. Half of the rats were then trained to self-administer meth (0.056 mg/kg/infusion) on a variable ratio 3 schedule of reinforcement; the other half earned intravenous saline during daily, 2 hour sessions. When responding stabilized, varenicline (0.0, 0.3, 1.0, 3.0 mg/kg) was tested to determine how it altered meth taking. Varenicline was probed on 4 test days; each test separated by 2 standard self-administration sessions to assure responding remained stable. Following this testing was 15 extinction sessions. Twenty-four hours after the last extinction session were four consecutive days of meth-primed reinstatement. The same 4 doses of varenicline were examined to determine how it altered reinstatement triggered by 0.3 mg/kg meth (IP). Rats readily self-administered meth. The higher doses of varenicline did not affect meth-taking in a specific fashion as active lever pressing wasalso slightly reduced in rats that has access to saline in the self-administration phase. Female rats displayed robust meth-primed reinstatement. Notably, the lower doses of varenicline increased meth-primed reinstatement. This amplified susceptibility to reinstatement (i.e., relapse) may be an impediment for the use of varenicline as a therapeutic to treat meth use disorder. PMID:26638833

  16. Effect of Electro-acupuncture on Relapse to Heroin-Seeking in the Heroin Self-administrating Rats

    Institute of Scientific and Technical Information of China (English)

    ZHU Zhong-chun; HU Jun; XU Ping

    2007-01-01

    To observe the effect of electro-acupuncture on the relapse to heroin-seeking induced by heroin-related cues after withdrawal from heroin self-administration in rats.Methods:Sixty male Wistar rats were randomized into physiological saline group,withdrawal group A,withdrawal group B,electro-acupuncture(EA)treatment group A and EA treatment group B,with 12 rats in each group.The rats were trained by nose-poke response to self administer heroin (50 μg/kg/per infusion) or saline with one daily 4-h session for 14 consecutive days,the session ended after 25 infusions were eamed or 4 hours had passed,the reinforcement schedule was a progressive ratio.Then rats in withdrawal group A and withdrawal group B were withdrawn from heroin for 1 week and 2 weeks respectively,and then they were reintroduced to their training chambers for 4-h relapse testing which was induced by heroin-related environmental cues;And rats in EA treatment group A and EA treatment group B were also withdrawn from heroin for 1 week and 2 weeks respectively,during which they were given EA treatment for 20 min daily,then they received relapse testing;In the meantime,rats in saline group were trained with saline instead of heroin for 14 days as control.after 7 days of withdrawal from saline,they received relapse testing.Results:Following 7-8 days of drug training,the rats began to establish the stable intravenous heroin self-administration behavior;For the stable heroin self-administrating rats that received EA treatment,when they were reintroduced to their training chambers,their heroin-seeking behaviors were obviously inhibited,and this inhibitory effect related to the cumulativeness of EA stimulation.Conclusion:The results suggested that EA could prevent relapse to heroin-seeking to a certain extent.

  17. The anabolic steroid nandrolone alters cannabinoid self-administration and brain CB1 receptor density and function.

    Science.gov (United States)

    Struik, Dicky; Fadda, Paola; Zara, Tamara; Zamberletti, Erica; Rubino, Tiziana; Parolaro, Daniela; Fratta, Walter; Fattore, Liana

    2017-01-01

    Clinical and pre-clinical observations indicate that anabolic-androgenic steroids can induce neurobiological changes that alter the rewarding effects of drugs of abuse. In this study, we investigated the effect of the anabolic steroid nandrolone on the rewarding properties of the cannabinoid CB1 receptor agonist WIN55,212-2 (WIN) in rats. Lister Hooded male rats were treated intramuscularly with nandrolone (15mg/kg) or vehicle for 14 consecutive days, and then allowed to self-administer WIN (12.5μg/kg/infusion) intravenously. After reaching stable drug intake, self-administration behavior was extinguished to examine drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Other behavioral parameters presumed to influence drug-taking and drug-seeking behaviors were examined to gain more insight into the behavioral specificity of nandrolone treatment. Finally, animals were sacrificed for analysis of CB1 receptor density and function in selected brain areas. We found that nandrolone-treated rats self-administered up to 2 times more cannabinoid than vehicle-treated rats, but behaved similarly to control rats when tested for drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Enhanced cannabinoid intake by nandrolone-treated rats was not accompanied by changes in locomotor activity, sensorimotor gating, or memory function. However, our molecular data show that after chronic WIN self-administration nandrolone-treated rats display altered CB1 receptor density and function in selected brain areas. We hypothesize that increased cannabinoid self-administration in nandrolone-treated rats results from a nandrolone-induced decrease in reward function, which rats seem to compensate by voluntarily increasing their cannabinoid intake. Altogether, our findings corroborate the hypothesis that chronic exposure to anabolic-androgenic steroids induces dysfunction of the reward pathway in rats and might represent a potential risk factor for abuse of

  18. Intense sweetness surpasses cocaine reward.

    Directory of Open Access Journals (Sweden)

    Magalie Lenoir

    Full Text Available BACKGROUND: Refined sugars (e.g., sucrose, fructose were absent in the diet of most people until very recently in human history. Today overconsumption of diets rich in sugars contributes together with other factors to drive the current obesity epidemic. Overconsumption of sugar-dense foods or beverages is initially motivated by the pleasure of sweet taste and is often compared to drug addiction. Though there are many biological commonalities between sweetened diets and drugs of abuse, the addictive potential of the former relative to the latter is currently unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that when rats were allowed to choose mutually-exclusively between water sweetened with saccharin-an intense calorie-free sweetener-and intravenous cocaine-a highly addictive and harmful substance-the large majority of animals (94% preferred the sweet taste of saccharin. The preference for saccharin was not attributable to its unnatural ability to induce sweetness without calories because the same preference was also observed with sucrose, a natural sugar. Finally, the preference for saccharin was not surmountable by increasing doses of cocaine and was observed despite either cocaine intoxication, sensitization or intake escalation-the latter being a hallmark of drug addiction. CONCLUSIONS: Our findings clearly demonstrate that intense sweetness can surpass cocaine reward, even in drug-sensitized and -addicted individuals. We speculate that the addictive potential of intense sweetness results from an inborn hypersensitivity to sweet tastants. In most mammals, including rats and humans, sweet receptors evolved in ancestral environments poor in sugars and are thus not adapted to high concentrations of sweet tastants. The supranormal stimulation of these receptors by sugar-rich diets, such as those now widely available in modern societies, would generate a supranormal reward signal in the brain, with the potential to override self

  19. Effects of an oxycodone conjugate vaccine on oxycodone self-administration and oxycodone-induced brain gene expression in rats.

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    Marco Pravetoni

    Full Text Available Prescription opioid abuse is an increasing public health concern in the USA. A vaccine comprising a hapten (OXY conjugated to the carrier protein keyhole limpet hemocyanin (OXY-KLH has been shown to attenuate the antinociceptive effects of oxycodone. Here, the vaccine's ability to prevent acquisition of intravenous (i.v. oxycodone self-administration was studied in rats. Effects of vaccination on oxycodone-induced changes in the expression of several genes within the mesolimbic system, which are regulated by chronic opiate use, were also examined. Vaccination with OXY-KLH reduced the proportion of rats acquiring i.v. self-administration of oxycodone under a fixed ratio (FR 3 schedule of reinforcement compared to control rats immunized with the unconjugated KLH carrier protein. Vaccination significantly reduced the mean number of infusions at FR3, total number of infusions, and total oxycodone intake during the entire protocol. Compared to oxycodone self-administering control rats immunized with the carrier alone, rats vaccinated with the OXY-KLH immunogen showed increased levels of adenylate cyclase 5 (Adcy5 and decreased levels of early growth response protein 2 (Egr2 and the early immediate gene c-Fos in the striatum. These data suggest that vaccination with OXY-KLH can attenuate the reinforcing effects of oxycodone at a clinically-relevant exposure level. Analysis of mRNA expression identified some addiction-relevant markers that may be of interest in understanding oxycodone effects or the protection provided by vaccination.

  20. Methylphenidate and cocaine have a similar in vivo potency to block dopamine transporters in the human brain

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D. [Brookhaven National Lab., Upton, NY (United States)]|[State Univ. of New York, Stony Brook, NY (United States). Dept. of Psychiatry; Wang, G.J.; Fowler, J.S. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1999-05-28

    The reinforcing effects of cocaine and methylphenidate have been linked to their ability to block dopamine transporters (DAT). Though cocaine and methylphenidate have similar in vitro affinities for DAT the abuse of methylphenidate in humans is substantially lower than of cocaine. To test if differences in in vivo potency at the DAT between these two drugs could account for the differences in their abuse liability the authors compared the levels of DAT occupancies that they had previously reported separately for intravenous methylphenidate in controls and for intravenous cocaine in cocaine abusers. DAT occupancies were measured with Positron Emission Tomography using [{sup 11}C]cocaine, as a DAT ligand, in 8 normal controls for the methylphenidate study and in 17 active cocaine abusers for the cocaine study. The ratio of the distribution volume of [{sup 11}C]cocaine in striatum to that in cerebellum, which corresponds to Bmax/Kd+1, was used as measure of DAT availability. Parallel measures were obtained to assess the cardiovascular effects of these two drugs. Methylphenidate and cocaine produced comparable dose-dependent blockage of DAT with an estimated ED{sub 50} for methylphenidate of 0.07 mg/kg and for cocaine of 0.13 mg/kg. Both drugs induced similar increases in heart rate and blood pressure but the duration of the effects were significantly longer for methylphenidate than for cocaine.

  1. A Multilevel Structural Equation Model of Within- and Between-Person Associations among Subjective Responses to Alcohol, Craving, and Laboratory Alcohol Self-Administration

    Science.gov (United States)

    Wardell, Jeffrey D.; Ramchandani, Vijay A.; Hendershot, Christian S.

    2017-01-01

    Subjective responses to alcohol are important determinants of drinking behavior and have been linked with risk for alcohol use disorders. However, few attempts have been made to examine proximal within-person associations among state changes in subjective responses and ongoing alcohol self-administration in the laboratory. This study disaggregated within- and between-person associations among subjective responses and alcohol self-administration, while also examining the mediating role of craving and the moderating role of trait impaired control over alcohol. Sixty young heavy drinkers (mean age=19.90, SD=0.86) completed self-report measures including the Impaired Control Scale, then participated in a 2-hour intravenous alcohol self-administration session using the Computer-Assisted Self-infusion of Ethanol (CASE) paradigm. Repeated assessments of subjective stimulation, subjective sedation, and craving were examined in relation to ongoing in-session self-administration, as indexed by breath alcohol concentration (BrAC) assessed 15 minutes later. Multilevel structural equation modeling was used to disentangle within-person and between-person associations. The results showed few significant associations at the between-person level, except for a direct negative association between sedation and BrAC. At the within-person level, state fluctuations in stimulation were positively associated with both craving and subsequent BrAC, whereas state changes in sedation were negatively associated with craving and positively associated with BrAC. Within-person indirect associations from subjective stimulation and sedation to subsequent BrAC mediated via craving were statistically significant. Also, participants higher on impaired control showed stronger within-person associations between craving and greater subsequent BrAC. The results suggest that subjective responses to alcohol and craving have proximal associations with self-administration behavior, the strength of which is

  2. Dorsal medial prefrontal cortex (MPFC) circuitry in rodent models of cocaine use: implications for drug addiction therapies.

    Science.gov (United States)

    Jasinska, Agnes J; Chen, Billy T; Bonci, Antonello; Stein, Elliot A

    2015-03-01

    Although the importance of the medial prefrontal cortex (MPFC) in cocaine addiction is well established, its precise contribution to cocaine seeking, taking and relapse remains incompletely understood. In particular, across two different models of cocaine self-administration, pharmacological or optogenetic activation of the dorsal MPFC has been reported to sometimes promote and sometimes inhibit cocaine seeking. We highlight important methodological differences between the two experimental paradigms and propose a framework to potentially reconcile the apparent discrepancy. We also draw parallels between these pre-clinical models of cocaine self-administration and human neuro-imaging studies in cocaine users, and argue that both lines of evidence point to dynamic interactions between cue-reactivity processes and control processes within the dorsal MPFC circuitry. From a translational perspective, these findings underscore the importance of interventions and therapeutics targeting not just a brain region, but a specific computational process within that brain region, and may have implications for the design and implementation of more effective treatments for human cocaine addiction. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  3. Cocaine addiction as a homeostatic reinforcement learning disorder.

    Science.gov (United States)

    Keramati, Mehdi; Durand, Audrey; Girardeau, Paul; Gutkin, Boris; Ahmed, Serge H

    2017-03-01

    Drug addiction implicates both reward learning and homeostatic regulation mechanisms of the brain. This has stimulated 2 partially successful theoretical perspectives on addiction. Many important aspects of addiction, however, remain to be explained within a single, unified framework that integrates the 2 mechanisms. Building upon a recently developed homeostatic reinforcement learning theory, the authors focus on a key transition stage of addiction that is well modeled in animals, escalation of drug use, and propose a computational theory of cocaine addiction where cocaine reinforces behavior due to its rapid homeostatic corrective effect, whereas its chronic use induces slow and long-lasting changes in homeostatic setpoint. Simulations show that our new theory accounts for key behavioral and neurobiological features of addiction, most notably, escalation of cocaine use, drug-primed craving and relapse, individual differences underlying dose-response curves, and dopamine D2-receptor downregulation in addicts. The theory also generates unique predictions about cocaine self-administration behavior in rats that are confirmed by new experimental results. Viewing addiction as a homeostatic reinforcement learning disorder coherently explains many behavioral and neurobiological aspects of the transition to cocaine addiction, and suggests a new perspective toward understanding addiction. (PsycINFO Database Record

  4. Amphetamine self-administration attenuates dopamine D2 autoreceptor function.

    Science.gov (United States)

    Calipari, Erin S; Sun, Haiguo; Eldeeb, Khalil; Luessen, Deborah J; Feng, Xin; Howlett, Allyn C; Jones, Sara R; Chen, Rong

    2014-07-01

    Dopamine D2 autoreceptors located on the midbrain dopaminergic neurons modulate dopamine (DA) neuron firing, DA release, and DA synthesis through a negative-feedback mechanism. Dysfunctional D2 autoreceptors following repeated drug exposure could lead to aberrant DA activity in the ventral tegmental area (VTA) and projection areas such as nucleus accumbens (NAcc), promoting drug-seeking and -taking behavior. Therefore, it is important to understand molecular mechanisms underlying drug-induced changes in D2 autoreceptors. Here, we reported that 5 days of amphetamine (AMPH) self-administration reduced the ability of D2 autoreceptors to inhibit DA release in the NAcc as determined by voltammetry. Using the antibody-capture [(35)S]GTPγS scintillation proximity assay, we demonstrated for the first time that midbrain D2/D3 receptors were preferentially coupled to Gαi2, whereas striatal D2/D3 receptors were coupled equally to Gαi2 and Gαo for signaling. Importantly, AMPH abolished the interaction between Gαi2 and D2/D3 receptors in the midbrain while leaving striatal D2/D3 receptors unchanged. The disruption of the coupling between D2/D3 receptors and Gαi2 by AMPH is at least partially explained by the enhanced RGS2 (regulator of G-protein signaling 2) activity resulting from an increased RGS2 trafficking to the membrane. AMPH had no effects on the midbrain expression and trafficking of other RGS proteins such as RGS4 and RGS8. Our data suggest that midbrain D2/D3 receptors are more susceptible to AMPH-induced alterations. Reduced D2 autoreceptor function could lead to enhanced DA signaling and ultimately addiction-related behavior. RGS2 may be a potential non-dopaminergic target for pharmacological intervention of dysfunctional DA transmission and drug addiction.

  5. Amphetamine Self-Administration Attenuates Dopamine D2 Autoreceptor Function

    Science.gov (United States)

    Calipari, Erin S; Sun, Haiguo; Eldeeb, Khalil; Luessen, Deborah J; Feng, Xin; Howlett, Allyn C; Jones, Sara R; Chen, Rong

    2014-01-01

    Dopamine D2 autoreceptors located on the midbrain dopaminergic neurons modulate dopamine (DA) neuron firing, DA release, and DA synthesis through a negative-feedback mechanism. Dysfunctional D2 autoreceptors following repeated drug exposure could lead to aberrant DA activity in the ventral tegmental area (VTA) and projection areas such as nucleus accumbens (NAcc), promoting drug-seeking and -taking behavior. Therefore, it is important to understand molecular mechanisms underlying drug-induced changes in D2 autoreceptors. Here, we reported that 5 days of amphetamine (AMPH) self-administration reduced the ability of D2 autoreceptors to inhibit DA release in the NAcc as determined by voltammetry. Using the antibody-capture [35S]GTPγS scintillation proximity assay, we demonstrated for the first time that midbrain D2/D3 receptors were preferentially coupled to Gαi2, whereas striatal D2/D3 receptors were coupled equally to Gαi2 and Gαo for signaling. Importantly, AMPH abolished the interaction between Gαi2 and D2/D3 receptors in the midbrain while leaving striatal D2/D3 receptors unchanged. The disruption of the coupling between D2/D3 receptors and Gαi2 by AMPH is at least partially explained by the enhanced RGS2 (regulator of G-protein signaling 2) activity resulting from an increased RGS2 trafficking to the membrane. AMPH had no effects on the midbrain expression and trafficking of other RGS proteins such as RGS4 and RGS8. Our data suggest that midbrain D2/D3 receptors are more susceptible to AMPH-induced alterations. Reduced D2 autoreceptor function could lead to enhanced DA signaling and ultimately addiction-related behavior. RGS2 may be a potential non-dopaminergic target for pharmacological intervention of dysfunctional DA transmission and drug addiction. PMID:24513972

  6. Methylphenidate Treatment in Adolescent Rats with an Attention Deficit/Hyperactivity Disorder Phenotype: Cocaine Addiction Vulnerability and Dopamine Transporter Function

    Science.gov (United States)

    Harvey, Roxann C; Sen, Sucharita; Deaciuc, Agripina; Dwoskin, Linda P; Kantak, Kathleen M

    2011-01-01

    Appropriate animal models of attention deficit/hyperactivity disorder (ADHD) and drug reinforcement allow investigation of possible underlying biological bases of ADHD and its comorbidity with cocaine addiction. Toward this end, spontaneously hypertensive rats (SHRs) exhibiting an ADHD phenotype were compared with Wistar-Kyoto (WKY) and Wistar (WIS) rats. Initially, 1.5 mg/kg oral methylphenidate or vehicle was administered between postnatal days 28 and 55, and acquisition of visual discrimination learning was examined. After discontinuing adolescent treatments, adult rats were evaluated for cocaine self-administration and dopamine transporter (DAT) function in the prefrontal cortex (PFC) and striatum. During adolescence, SHRs showed deficits in visual discrimination relative to WKY and WIS rats when non-medicated. Methylphenidate improved visual discrimination only in SHRs. Compared with WKY and WIS rats, SHRs with previous methylphenidate treatment acquired cocaine self-administration faster, identified cocaine as a highly efficacious reinforcer by displaying an upward shift in the cocaine dose–response function, and showed the greatest motivation to self-administer cocaine by exhibiting the highest progressive ratio breakpoints. In the PFC, the maximal dopamine uptake (Vmax) at DAT was decreased in SHRs and increased in WKY and WIS rats by previous methylphenidate treatment. The affinity (Km) for dopamine at DAT in the PFC was not different between strains, nor was Vmax or Km altered in the striatum by previous methylphenidate treatment in any strain. Methylphenidate-induced decreases in dopamine clearance by DAT in the PFC may underlie increased cocaine self-administration in SHRs. These preclinical findings suggest that caution should be exercised when methylphenidate is prescribed for first-time treatment of ADHD in adolescent patients, as cocaine addiction vulnerability may be augmented. PMID:21150910

  7. Dopamine D3 receptor-preferring agonist enhances the subjective effects of cocaine in humans.

    Science.gov (United States)

    Newton, Thomas F; Haile, Colin N; Mahoney, James J; Shah, Ravi; Verrico, Christopher D; De La Garza, Richard; Kosten, Thomas R

    2015-11-30

    Pramipexole is a D3 dopamine receptor-preferring agonist indicated for the treatment of Parkinson disease. Studies associate pramipexole with pathological gambling and impulse control disorders suggesting a role for D3 receptors in reinforcement processes. Clinical studies showed pramipexole decreased cocaine craving and reversed central deficits in individuals with cocaine use disorder. Preclinical studies have shown acute administration of pramipexole increases cocaine's reinforcing effects whereas other reports suggest chronic pramipexole produces tolerance to cocaine. In a randomized, double-blind, placebo-controlled study we examined the impact of pramipexole treatment on the subjective effects produced by cocaine in volunteers with cocaine use disorder. Volunteers received pramipexole titrated up to 3.0mg/d or placebo over 15 days. Participants then received intravenous cocaine (0, 20 and 40mg) on day 15. Cardiovascular and subjective effects were obtained with visual analog scales at time points across the session. Pramipexole alone increased peak heart rate following saline and diastolic blood pressure following cocaine. Pramipexole produced upwards of two-fold increases in positive subjective effects ratings following cocaine. These results indicate that chronic D3 receptor activation increases the subjective effects of cocaine in humans. Caution should be used when prescribing pramipexole to patients that may also use cocaine.

  8. Intracerebroventricular Oxytocin Self-Administration in Female Rats.

    Science.gov (United States)

    Donhoffner, M E; Goings, S P; Atabaki, K; Wood, R I

    2016-10-01

    Oxytocin (OT) is a neuromodulator that facilitates pair-bonding, maternal care and social approach. OT is considered to promote these social behaviours by enhancing the salience and reinforcing effects of relevant social stimuli. There is the additional possibility that OT per se may be rewarding. To test this, we investigated whether female rats would voluntarily self-administer OT. Female Long-Evans rats were ovariectomised and then received an oestrogen implant and an i.c.v. cannula. Rats were tested in an operant chamber with active and inactive levers. They were initially tested for 4 h/day on a fixed-ratio 5 schedule for self-administration of artificial cerebral spinal fluid (aCSF) for 5 days, followed by aCSF, or OT, at 1 or 10 ng/μl for another 5 days. Rats self-administering aCSF made 36.2 ± 6.2 active lever responses/4 h versus 14.9 ± 3.4 inactive responses. Responses for 1 ng/μl OT were similar. However, rats self-administering 10 ng/μl OT made significantly more active lever responses (67.8 ± 12.0 per 4 h), and received 121.4 ± 21.0 ng OT/4 h. To determine whether reduced anxiety contributes to the reinforcing effects of OT, rats received an infusion of aCSF or OT at 0.3 or 3.0 μg immediately before testing on the elevated plus maze. There was no effect of OT on anxiety as reflected by percentage time spent on the open arms, as well as no effect of OT on locomotion as measured either by the number of closed arm entries or the number of total arm entries. These results suggest that OT may be rewarding, and that this is not a result of the anxiolytic effects of OT.

  9. The Effects of Excitatory and Inhibitory Social Cues on Cocaine-Seeking Behavior

    Directory of Open Access Journals (Sweden)

    Mark Andrew Smith

    2016-11-01

    Full Text Available Social partners influence the likelihood of using drugs, developing a substance use disorder, and relapse to drug use after a period of abstinence. Preclinical studies report that social cues influence the acquisition of cocaine use, the escalation of cocaine use over time, and the compulsive patterns of cocaine use that emerge during an extended binge. The purpose of this study was to examine the effects of social cues on the reinstatement of cocaine-seeking behavior after a period of abstinence. Male rats were obtained at weaning, assigned to triads (3 rats/cage, reared to adulthood, and implanted with intravenous catheters. Rats from each triad were then assigned to one of three conditions: (1 test rats were trained to self-administer cocaine and were tested for reinstatement, (2 cocaine partners were trained to self-administer cocaine and were predictive of response-contingent cocaine delivery, and (3 abstinent partners were not given access to cocaine and were predictive of extinction. Test rats alternated social partners every 5 days for 20 days such that responding was reinforced with cocaine in the presence of the cocaine partner (S+ for 10 days and not reinforced with cocaine in the presence of the abstinent partner (S- for 10 days. Responding of the test rats was then extinguished over 7 days under isolated conditions. Tests of reinstatement were then conducted in the presence of the cocaine partner and abstinent partner under extinction conditions. Neither social partner reinstated responding relative to that observed on the final day of extinction; however, responding was greater in the presence of the cocaine partner (S+ than the abstinent partner (S- during the reinstatement test. These data fail to demonstrate that a social partner reinstates cocaine-seeking behavior after a period of abstinence, but they do indicate that social partners can serve as either excitatory or inhibitory discriminative stimuli to influence drug

  10. The Effects of Excitatory and Inhibitory Social Cues on Cocaine-Seeking Behavior

    Science.gov (United States)

    Smith, Mark A.; Zhang, Huailin; Robinson, Andrea M.

    2016-01-01

    Social partners influence the likelihood of using drugs, developing a substance use disorder and relapse to drug use after a period of abstinence. Preclinical studies report that social cues influence the acquisition of cocaine use, the escalation of cocaine use over time, and the compulsive patterns of cocaine use that emerge during an extended binge. The purpose of this study was to examine the effects of social cues on the reinstatement of cocaine-seeking behavior after a period of abstinence. Male rats were obtained at weaning, assigned to triads (three rats/cage), reared to adulthood and implanted with intravenous catheters. Rats from each triad were then assigned to one of three conditions: (1) test rats were trained to self-administer cocaine and were tested for reinstatement; (2) cocaine partners were trained to self-administer cocaine and were predictive of response-contingent cocaine delivery; and (3) abstinent partners were not given access to cocaine and were predictive of extinction. The test rats alternated social partners every 5 days for 20 days such that responding was reinforced with cocaine in the presence of the cocaine partner (S+) for 10 days and not reinforced with cocaine in the presence of the abstinent partner (S−) for 10 days. Responding of the test rats was then extinguished over 7 days under isolated conditions. Tests of reinstatement were then conducted in the presence of the cocaine partner and abstinent partner under extinction conditions. Neither social partner reinstated responding relative to that observed on the final day of extinction; however, responding was greater in the presence of the cocaine partner (S+) than the abstinent partner (S−) during the reinstatement test. These data fail to demonstrate that a social partner reinstates cocaine-seeking behavior after a period of abstinence, but they do indicate that social partners can serve as either excitatory or inhibitory discriminative stimuli to influence drug

  11. Dissociation of the effects of MTEP [3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]piperidine] on conditioned reinstatement and reinforcement: comparison between cocaine and a conventional reinforcer.

    Science.gov (United States)

    Martin-Fardon, R; Baptista, M A S; Dayas, C V; Weiss, F

    2009-06-01

    To advance understanding of the potential of metabotropic glutamate receptor (mGluR) 5 as treatment targets for cocaine addiction, the effects of MTEP [3-[(2-methyl-1,3-thiazol-4-yl) ethynyl]piperidine] (a selective mGluR5 antagonist) on conditioned reinstatement of cocaine seeking were examined. To test whether modification of conditioned reinstatement by MTEP is selective for drug-directed behavior or reflects general actions on motivated behavior, effects of MTEP on reinstatement induced by a stimulus conditioned to palatable conventional reward, sweetened condensed milk (SCM), were also evaluated. Previous data suggest that mGluR manipulations preferentially interfere with conditioned reinstatement compared with cocaine self-administration. Therefore, the effects of MTEP on cocaine self-administration were compared with MTEP's effects on SCM-reinforced behavior using the same cocaine doses and SCM concentrations employed for establishing conditioned reinstatement. Male Wistar rats were trained to associate a discriminative stimulus (S(D)) with response-contingent availability of cocaine or SCM and subjected to reinstatement tests after extinction of cocaine or SCM-reinforced behavior. MTEP (0.3-10 mg/kg i.p.) dose-dependently attenuated the response-reinstating effects of both the cocaine S(D) and SCM S(D). MTEP also decreased cocaine self-administration without a clear graded dose-response profile and did not modify SCM-reinforced responding. The findings implicate mGluR5-regulated glutamate transmission in appetitive behavior controlled by reward-related stimuli but without selectivity for cocaine seeking. However, the data suggest a differential role for mGluR5 in the acute reinforcing effects of cocaine versus conventional reward. These observations identify mGluR5 as potential treatment targets for cocaine relapse prevention, although the profile of action of mGluR5 antagonists remains to be more closely examined for potential anhedonic effects.

  12. Nosocomial Methemoglobinemia Resulting from Self-Administration of Benzocaine Spray

    Directory of Open Access Journals (Sweden)

    Christopher Hoffman

    2015-01-01

    Full Text Available Methemoglobinemia is life-threatening and bears pathognomonic signs difficult to diagnose in real time. Local anesthetics are widely used and are known for eliciting this condition. We report a case of methemoglobinemia secondary to self-administered use of benzocaine spray. A 27-year-old woman was found to be in respiratory distress during postoperative recovery. After desaturation persisted, arterial blood gas yielded a methemoglobin level of 47%. The patient was successfully treated with intravenous methylene blue. Review of the events revealed self-administered doses of benzocaine spray to alleviate discomfort from a nasogastric tube. We review this case in detail in addition to discussing methemoglobinemia and its relevant biochemistry, pathophysiology, clinical presentation, and medical management. Given the recognized risk of methemoglobinemia associated with benzocaine use, we recommend its removal from the market in favor of safer alternatives.

  13. Stress Alters the Discriminative Stimulus and Response Rate Effects of Cocaine Differentially in Lewis and Fischer Inbred Rats

    Directory of Open Access Journals (Sweden)

    Therese A. Kosten

    2012-03-01

    Full Text Available Stress enhances the behavioral effects of cocaine, perhaps via hypothalamic-pituitary-adrenal (HPA axis activity. Yet, compared to Fischer 344 (F344 rats, Lewis rats have hyporesponsive HPA axis function and more readily acquire cocaine self-administration. We hypothesized that stress would differentially affect cocaine behaviors in these strains. The effects of three stressors on the discriminative stimulus and response rate effects of cocaine were investigated. Rats of both strains were trained to discriminate cocaine (10 mg/kg from saline using a two-lever, food-reinforced (FR10 procedure. Immediately prior to cumulative dose (1, 3, 10 mg/kg cocaine test sessions, rats were restrained for 15-min, had 15-min of footshock in a distinct context, or were placed in the shock-paired context. Another set of F344 and Lewis rats were tested similarly except they received vehicle injections to test if stress substituted for cocaine. Most vehicle-tested rats failed to respond after stressor exposures. Among cocaine-tested rats, restraint stress enhanced cocaine’s discriminative stimulus effects in F344 rats. Shock and shock-context increased response rates in Lewis rats. Stress-induced increases in corticosterone levels showed strain differences but did not correlate with behavior. These data suggest that the behavioral effects of cocaine can be differentially affected by stress in a strain-selective manner.

  14. Suppressing effect of saikosaponin A, an active ingredient of Bupleurum falcatum, on chocolate self-administration and reinstatement of chocolate seeking in rats.

    Science.gov (United States)

    Lorrai, Irene; Maccioni, Paola; Carai, Mauro A M; Capra, Alessandro; Castelli, M Paola; Riva, Antonella; Morazzoni, Paolo; Gessa, Gian Luigi; Colombo, Giancarlo

    2017-01-18

    Recent lines of experimental evidence have indicated that saikosaponin A (SSA) - a bioactive ingredient of the medicinal plant, Bupleurum falcatum L. - suppressed alcohol, morphine, and cocaine self-administration in rats. The present paper was designed to assess whether the protective properties of SSA on addiction-related behaviors generalize to a hyperpalatable food such as a chocolate-flavored beverage (CFB). To this end, rats were initially trained to lever-respond for CFB [5% (w/v) Nesquik(®) powder in water] under fixed ratio (FR) 10 (FR10) schedule of reinforcement. Once lever-responding reached stable levels, rats were treated acutely with two different dose ranges of SSA (0, 0.25, 0.5, and 1mg/kg; 0, 1, 2.5, and 5mg/kg; i.p.) and exposed to the FR10 and progressive ratio (PR) schedules of reinforcement in four independent experiments. The effect of acutely administered SSA (0, 0.25, 0.5, and 1mg/kg; i.p.) on cue-induced reinstatement of seeking behavior for CFB was also assessed. Under the FR and PR schedules of reinforcement, treatment with SSA diminished lever-responding for CFB, amount of self-administered CFB, and breakpoint for CFB. All variables were virtually completely suppressed after treatment with 5mg/kg SSA. Treatment with SSA also suppressed reinstatement of CFB-seeking behavior. No dose of SSA altered rat motor-performance, evaluated exposing all rats to an inverted screen test immediately after the self-administration session. These results demonstrate that acute treatment with SSA potently suppressed several addictive-like behaviors motivated by highly hedonic nourishment. These data extend to a highly rewarding natural stimulus the anti-addictive properties of SSA recently disclosed in rats self-administering alcohol, morphine, and cocaine.

  15. Sex differences in selecting between food and cocaine reinforcement are mediated by estrogen.

    Science.gov (United States)

    Kerstetter, Kerry A; Ballis, Maya A; Duffin-Lutgen, Stevie; Carr, Amanda E; Behrens, Alexandra M; Kippin, Tod E

    2012-11-01

    Cocaine-dependent women, relative to their male counterparts, report shorter cocaine-free periods and report transiting faster from first use to entering treatment for addiction. Similarly, preclinical studies indicate that female rats, particularly those in the estrus phase of their reproductive cycle, show increased operant responding for cocaine under a wide variety of schedules. Making maladaptive choices is a component of drug dependence, and concurrent reinforcement schedules that examine cocaine choice offers an animal model of the conditions of human drug use; therefore, the examination of sex differences in decision-making may be critical to understanding why women display a more severe profile of cocaine addiction than men. Accordingly, we assessed sex and estrous cycle differences in choice between food (45 mg grain pellets) and intravenous cocaine (0.4 or 1.0 mg/kg per infusion) reinforcement in male, female (freely cycling), and ovariectomized (OVX) females treated with either estrogen benzoate (EB; 5 μg per day) or vehicle. At both cocaine doses, intact female rats choose cocaine over food significantly more than male rats. However, the estrous cycle did not impact the level of cocaine choice in intact females. Nevertheless, OVX females treated with vehicle exhibited a substantially lower cocaine choice compared with those receiving daily EB or to intact females. These results demonstrate that intact females have a greater preference for cocaine over food compared with males. Furthermore, this higher preference is estrogen-dependent, but does not vary across the female reproductive cycle, suggesting that ovarian hormones regulate cocaine choice. The present findings indicate that there is a biological predisposition for females to forgo food reinforcement to obtain cocaine reinforcement, which may substantially contribute to women experiencing a more severe profile of cocaine addiction than men.

  16. Serotonin2C receptors and drug addiction: focus on cocaine.

    Science.gov (United States)

    Devroye, Céline; Filip, Malgorzata; Przegaliński, Edmund; McCreary, Andrew C; Spampinato, Umberto

    2013-10-01

    This review provides an overview of the role of central serotonin2C (5-HT2C) receptors in drug addiction, specifically focusing on their impact on the neurochemical and behavioral effects of cocaine, one of the most worldwide abused drug. First, we described the neurochemical and electrophysiological mechanisms underlying the interaction between 5-HT2C receptors and the mesocorticolimbic dopaminergic network, in keeping with the key role of this system in drug abuse and dependence. Thereafter, we focused on the role of 5-HT2C receptors in the effects of cocaine in various preclinical behavioral models used in drug addiction research, such as locomotor hyperactivity, locomotor sensitization, drug discrimination, and self-administration, to end with an overview of the neurochemical mechanisms underlying the interactions between 5-HT2C receptors, mesocorticolimbic dopamine system, and cocaine. On their whole, the presented data provide compelling preclinical evidence that 5-HT2C receptor agonists may have efficacy in the treatment of cocaine abuse and dependence, thereby underlying the need for additional clinical studies to ascertain whether preclinical data translate to the human.

  17. Glutamate transporter GLT-1 mediates N-acetylcysteine inhibition of cocaine reinstatement.

    Science.gov (United States)

    Reissner, Kathryn J; Gipson, Cassandra D; Tran, Phuong K; Knackstedt, Lori A; Scofield, Michael D; Kalivas, Peter W

    2015-03-01

    Both pre-clinical and clinical studies indicate that N-acetylcysteine (NAC) may be useful in treating relapse to addictive drug use. Cocaine self-administration in rats reduces both cystine-glutamate exchange and glutamate transport via GLT-1 in the nucleus accumbens, and NAC treatment normalizes these two glial processes critical for maintaining glutamate homeostasis. However, it is not known if one or both of these actions by NAC is needed to inhibit relapse to cocaine seeking. To determine whether the restoration of GLT-1 and/or cystine-glutamate exchange is required for NAC to inhibit cue-induced reinstatement of cocaine seeking, we utilized the rat self-administration/extinction/reinstatement model of cocaine relapse. Rats were pre-treated in the nucleus accumbens with vivo-morpholino antisense oligomers targeting either GLT-1 or xCT (catalytic subunit of the cystine-glutamate exchanger) overlapping with daily NAC administration during extinction (100 mg/kg, i.p. for the last 5 days). Rats then underwent cue-induced reinstatement of active lever pressing in the absence of NAC, to determine if preventing NAC-induced restoration of one or the other protein was sufficient to block the capacity of chronic NAC to inhibit reinstatement. The vivo-morpholino suppression of xCT reduced cystine-glutamate exchange but did not affect NAC-induced reduction of reinstated cocaine seeking. In contrast, suppressing NAC-induced restoration of GLT-1 not only prevented NAC from inhibiting reinstatement, but augmented the capacity of cues to reinstate cocaine seeking. We hypothesized that the increased reinstatement after inhibiting NAC induction of GLT-1 resulted from increased extracellular glutamate, and show that augmented reinstatement is prevented by blocking mGluR5. Restoring GLT-1, not cystine-glutamate exchange, is a key mechanism whereby daily NAC reduces cue-induced cocaine reinstatement.

  18. Cocaine and the nervous system.

    Science.gov (United States)

    Prakash, A; Das, G

    1993-12-01

    Cocaine abuse today has reached greater heights than it did during the first cocaine epidemic in the late nineteenth century. It is estimated that one out of every four Americans has used cocaine and some six million people in the US use it regularly. Although cocaine affects all systems in the body, the central nervous system (CNS) is the primary target. Cocaine blocks the reuptake of neurotransmitters in the neuronal synapses. Almost all CNS effects of cocaine can be attributed to this mechanism. Euphoria, pharmacological pleasure and intense cocaine craving share basis in this system. The effects of cocaine on other organ systems, in addition to its effects on the CNS, account for the majority of the complications associated with cocaine abuse. In this paper, the CNS effects following cocaine administration and their treatment are discussed.

  19. Opioid self-administration results in cell-type specific adaptations of striatal medium spiny neurons.

    Science.gov (United States)

    James, Alex S; Chen, Jane Y; Cepeda, Carlos; Mittal, Nitish; Jentsch, James David; Levine, Michael S; Evans, Christopher J; Walwyn, Wendy

    2013-11-01

    Medium-sized spiny neurons (MSNs), the predominant neuronal population of the striatum, are an integral component of the many cortical and limbic pathways associated with reward-related behaviors. A differential role of the D1 receptor-enriched (D1) MSNs of the striatonigral direct pathway, as compared with the D2 receptor-enriched (D2) MSNs of the striatopallidal indirect pathway, in mediating the addictive behaviors associated with cocaine is beginning to emerge. However, whether opioids, well-known analgesics with euphoric properties, similarly induce dissociable signaling adaptations in these neurons remains unclear. Transgenic mice expressing green fluorescent protein (GFP)-labeled D1 or D2 neurons were implanted with intravenous jugular catheters. Mice learned to self-administer 0.1mg/kg/infusion of the opioid remifentanil during 2h sessions over 13 contiguous days. Thereafter, the electrophysiological properties of D1- and D2-MSNs in the shell region of the nucleus accumbens (NAc) were assessed. We found that prior opioid exposure did not alter the basic membrane properties nor the kinetics or amplitude of miniature excitatory postsynaptic currents (mEPSCs). However, when challenged with the mu opioid receptor (μOR) agonist DAMGO, the characteristic inhibitory profile of this receptor was altered. DAMGO inhibited the frequency of mEPSCs in D1-MSNs from control mice receiving saline and in D2-MSNs from mice exposed to remifentanil or saline, but this inhibitory profile was reduced in D1-MSNs from mice receiving remifentanil. Remifentanil exposure also altered the probability of glutamate release onto D1-, but not D2-MSNs. Together these results suggest a D1-pathway specific effect associated with the acquisition of opioid-seeking behaviors. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Modafinil: a useful medication for cocaine addiction? Review of the evidence from neuropharmacological, experimental and clinical studies.

    Science.gov (United States)

    Martínez-Raga, Jose; Knecht, Carlos; Cepeda, Sonsoles

    2008-06-01

    Cocaine addiction is a chronic relapsing disorder associated with severe medical and psychosocial complications. However, there are no approved medications for cocaine dependent individuals. Modafinil, a medication that differs chemically and pharmacologically from other central nervous system stimulants, has been suggested to be potentially useful for this complex disorder. The present paper aims to critically review the published evidence from laboratory and clinical studies on modafinil for cocaine addiction, including discussion of its pharmacological characteristics and how it may relate with cocaine neurobiology. Whilst its exact mechanism of action remains to be elucidated, different neurotransmitter systems have been implicated, including modulation on dopamine, glutamate/GABA, noradrenaline and the hypocretin/orexin system, but it is possible that modafinil acts by a synergistic combination of mechanisms. With a favourable pharmacokinetic profile, it appears to have a low abuse potential. Laboratory and clinical studies provide consistent, albeit preliminary, evidence of the potential usefulness of modafinil for cocaine dependent patients. Not only there is no evidence of pharmacokinetic interactions between modafinil and cocaine, but in addition cocaine induced euphoria and cardiovascular effects appear to be attenuated by modafinil. Furthermore, modafinil has been shown to decrease cocaine self-administration. In addition, modafinil treated patient are more likely to achieve protracted abstinence than placebo treated patients. However, further research is needed to confirm these findings.

  1. Treatment of cocaine overdose with lipid emulsion.

    Science.gov (United States)

    Jakkala-Saibaba, R; Morgan, P G; Morton, G L

    2011-12-01

    We describe the management and recovery of a 28-year-old man following a history of overdose by nasal inhalation of cocaine. The patient was presented in a comatose state suffering from seizures and marked cardiovascularly instability. Intravenous lipid emulsion was administered following initial resuscitation and tracheal intubation, as a means of treating persistent cardiac arrhythmias and profound hypotension. Following lipid emulsion therapy, the patient's life-threatening cardiovascular parameters rapidly improved and he recovered well without any side effects, thus being discharged within 2 days. © 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

  2. Intracellular mechanisms of cocaine-memory reconsolidation in the basolateral amygdala and dorsal hippocampus

    Science.gov (United States)

    Wells, Audrey Marie

    The ability of cocaine-associated environmental contexts to promote relapse in abstinent humans and reinstatement of cocaine-seeking behavior in laboratory animals depends on the formation and maintenance of maladaptive context-response-cocaine associative memories, the latter of which can be disrupted by manipulations that interfere with memory reconsolidation. Memory reconsolidation refers to a protein synthesis-dependent phenomenon whereby memory traces are reincorporated back into long-term memory storage following their retrieval and subsequent destabilization. To elucidate the distinctive roles of the basolateral amygdala (BLA) and dorsal hippocampus (DH) in the reconsolidation of context-response-cocaine memories, Experiments 1-3 evaluated novel molecular mechanisms within each structure that control this phenomenon. Experiment 1 tested the hypothesis that activation of the extracellular signal-regulated kinase (ERK) in the BLA and nucleus accumbens core (NACc - a substrate for Pavlovian cocaine-memory reconsolidation) would critically control instrumental cocaine-memory reconsolidation. To determine this, rats were re-exposed to a context that had previously been used for cocaine self-administration (i.e., cocaine memory-reactivation) and immediately thereafter received bilateral intra-BLA or intra-NACc microinfusions of the ERK inhibitor U0126 or vehicle (VEH) and were subsequently tested for drug context-induced cocaine-seeking behavior (non-reinforced lever responding) ~72 h later. Re-exposure to the cocaine-paired context at test fully reinstated cocaine-seeking behavior, relative to responding in an alternate, extinction context, and post-reactivation U0126 treatment in the BLA, but not the NACc, impaired cocaine-seeking behavior, relative to VEH. This effect was associated with a temporary increase in ERK2, but not ERK1, phosphorylation in the BLA and required explicit reactivation of the target memory trace (i.e., did not similarly manifest when U

  3. Ascorbic acid decreases morphine self-administration and withdrawal symptoms in rats.

    Science.gov (United States)

    Alaei, H; Esmaeili, M; Nasimi, A; Pourshanazari, A

    2005-09-01

    Recent studies have indicated that the glutamatergic system is involved in the motivational aspects during the initiation of drug self-administration. Ascorbic acid (AA), an antioxidant vitamin, is released from glutamatergic neurons, and it modulates the synaptic action of dopamine and glutamate. In this study the AA effects on the self-administration of morphine and on the morphine withdrawal syndrome have been investigated. Wistar rats were allowed to self-administer morphine (1 mg/infusion) during 10 consecutive days for 2 h/session. The number of lever pressings was recorded. An intrapritoneal AA injection (500 mg/kg, i.p.), 30 min before morphine self-administration produced a significant decrease in the initiation of morphine self administration during all sessions. After the last test session morphine withdrawal symptom signs (MWS) were recorded after naloxone precipitation. Most of MWS (but not all) were decreased by AA application. In conclusion, AA may change the motivational processes underlying the morphine self-administration.

  4. Dendrosomal nanocurcumin prevents morphine self-administration behavior in rats despite CA1 damage.

    Science.gov (United States)

    Norozi, Jalaleden; Hassanpour-Ezatti, Majid; Alaei, Hojjat A

    2017-01-25

    Dendrosomal nanocurcumin (DNC) is fabricated from esterification of oleic acid and polyethylene glycol residues with curcumin. DNC has shown antioxidant, neuroprotective, and neurogenesis-enhancing effects. In addition, it can attenuate morphine tolerance. Morphine self-administration is associated with neurodegenerative changes of CA1 neurons in the adult hippocampus. The present study evaluated the effect of DNC pretreatment on morphine self-administration and hippocampal damage. Rats were pretreated with DNC (5 and 10 mg/kg, intraperitoneally) 30 min before a morphine self-administration paradigm performed in 2-h/sessions for 12 days under a FR-1 schedule. Pretreatment with both doses of DNC markedly suppressed morphine intake. Morphine self-administration resulted in a 71% reduction in the number of hippocampal CA1 neurons. DNC (5 mg/kg) pretreatment only marginally improved (by 22%) neuronal loss in this area. The data suggest that the effect of DNC on morphine self-administration is largely independent of the CA1 area. A functional restoration and regulation of reward circuit activity by DNC may reduce the motivation for morphine despite CA1 damage.

  5. Cocaine and Pregnancy

    Science.gov (United States)

    ... weight. Cocaine may increase the risk for preterm delivery. Babies who are born prematurely often start life with ... Is there any way to know if my baby has been harmed before delivery? If you are worried that your baby may ...

  6. Subunit Stabilization and Polyethylene Glycolation of Cocaine Esterase Improves In Vivo Residence Time

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, Diwahar; Collins, Gregory T.; Nance, Mark R.; Nichols, Joseph; Edwald, Elin; Chan, Jimmy; Ko, Mei-Chuan; Woods, James H.; Tesmer, John J.G.; Sunahara, Roger K. (Michigan)

    2012-03-15

    No small-molecule therapeutic is available to treat cocaine addiction, but enzyme-based therapy to accelerate cocaine hydrolysis in serum has gained momentum. Bacterial cocaine esterase (CocE) is the fastest known native enzyme that hydrolyzes cocaine. However, its lability at 37 C has limited its therapeutic potential. Cross-linking subunits through disulfide bridging is commonly used to stabilize multimeric enzymes. Herein we use structural methods to guide the introduction of two cysteine residues within dimer interface of CocE to facilitate intermolecular disulfide bond formation. The disulfide-crosslinked enzyme displays improved thermostability, particularly when combined with previously described mutations that enhance stability (T172R-G173Q). The newly modified enzyme yielded an extremely stable form of CocE (CCRQ-CocE) that retained greater than 90% of its activity after 41 days at 37 C, representing an improvement of more than 4700-fold over the wild-type enzyme. CCRQ-CocE could also be modified by polyethylene glycol (PEG) polymers, which improved its in vivo residence time from 24 to 72 h, as measured by a cocaine lethality assay, by self-administration in rodents, and by measurement of inhibition of cocaine-induced cardiovascular effects in rhesus monkeys. PEG-CCRQ elicited negligible immune response in rodents. Subunit stabilization and PEGylation has thus produced a potential protein therapeutic with markedly higher stability both in vitro and in vivo.

  7. Effects of perceived cocaine availability on subjective and objective responses to the drug

    Directory of Open Access Journals (Sweden)

    Lukas Scott E

    2007-10-01

    Full Text Available Abstract Rationale Several lines of evidence suggest that cocaine expectancy and craving are two related phenomena. The present study assessed this potential link by contrasting reactions to varying degrees of the drug's perceived availability. Method Non-treatment seeking individuals with cocaine dependence were administered an intravenous bolus of cocaine (0.2 mg/kg under 100% ('unblinded'; N = 33 and 33% ('blinded'; N = 12 probability conditions for the delivery of drug. Subjective ratings of craving, high, rush and low along with heart rate and blood pressure measurements were collected at baseline and every minute for 20 minutes following the infusions. Results Compared to the 'blinded' subjects, their 'unblinded' counterparts had similar craving scores on a multidimensional assessment several hours before the infusion, but reported higher craving levels on a more proximal evaluation, immediately prior to the receipt of cocaine. Furthermore, the 'unblinded' subjects displayed a more rapid onset of high and rush cocaine responses along with significantly higher cocaine-induced heart rate elevations. Conclusion These results support the hypothesis that cocaine expectancy modulates subjective and objective responses to the drug. Provided the important public health policy implications of heavy cocaine use, health policy makers and clinicians alike may favor cocaine craving assessments performed in the settings with access to the drug rather than in more neutral environments as a more meaningful marker of disease staging and assignment to the proper level of care.

  8. Self-administration of intravenous C1-inhibitor therapy for hereditary angioedema and associated quality of life benefits

    DEFF Research Database (Denmark)

    Bygum, Anette; Andersen, Klaus Ejner; Mikkelsen, Carsten Sauer

    2009-01-01

    Hereditary angioedema (HAE) is often debilitating with a serious effect on quality of life (QOL). Treatment of acute HAE attacks is usually with C1 esterase inhibitor (C1-INH) concentrates; however, treatment can be delayed by patients' travel time for attending emergency units. We assessed...

  9. Myocardial ischaemia following cocaine and adrenaline exposure in a child during an ophthalmological procedure.

    LENUS (Irish Health Repository)

    McGovern, E

    2015-03-01

    We report a 23-month old girl who presented with bilateral epiphora who underwent bilateral lacrimal probing and syringing, during which a cocaine adrenaline solution was used. Two hours after the procedure she developed acute pulmonary oedema secondary to myocardial ischaemia. The patient was treated with intravenous glyceryltrinitrate and milrinone infusions; cardiac enzymes and left ventricular function normalised over the subsequent 72 hours. Topical administration of cocaine and adrenaline solution may have dangerous systemic cardiac effects and should always be used judiciously.

  10. Attenuation of cocaine's reinforcing and discriminative stimulus effects via muscarinic M1 acetylcholine receptor stimulation

    DEFF Research Database (Denmark)

    Thomsen, Morgane; Conn, P Jeffrey; Lindsley, Craig

    2010-01-01

    Muscarinic cholinergic receptors modulate dopaminergic function in brain pathways thought to mediate cocaine's abuse-related effects. Here, we sought to confirm and extend in the mouse species findings that nonselective muscarinic receptor antagonists can enhance cocaine's discriminative stimulus....... More importantly, we tested the hypothesis that muscarinic receptor agonists with varied receptor subtype selectivity can blunt cocaine's discriminative stimulus and reinforcing effects; we hypothesized a critical role for the M(1) and/or M(4) receptor subtypes in this modulation. Mice were trained...... to discriminate cocaine from saline, or to self-administer intravenous cocaine chronically. The nonselective muscarinic antagonists scopolamine and methylscopolamine, the nonselective muscarinic agonists oxotremorine and pilocarpine, the M(1)/M(4)-preferring agonist xanomeline, the putative M(1)-selective agonist...

  11. The impact of disulfiram treatment on the reinforcing effects of cocaine: a randomized clinical trial.

    Directory of Open Access Journals (Sweden)

    Colin N Haile

    Full Text Available BACKGROUND: Clinical trials indicate that disulfiram (250 mg/d reduces cocaine use, though one study found that treatment with lower doses of disulfiram (62.5 and 125 mg/d increased cocaine use. We conducted the present study to better understand how disulfiram alters the reinforcing effects of cocaine in cocaine users. METHODS: Seventeen non-treatment seeking, cocaine-dependent volunteers participated in this double-blind, placebo-controlled, laboratory-based study. A cross-over design was utilized in which participants received placebo in one phase and disulfiram (250 mg/d in the other. Following three days of study medication participants completed two choice sessions. In one they made 10 choices between receiving an intravenous infusion of saline or money that increased in value (US$ 0.05-16 and in the other cocaine (20 mg or money. RESULTS: Participants chose cocaine more than saline under both disulfiram and placebo conditions (p<0.05. Unexpectedly, disulfiram increased both the number of cocaine and saline infusion choices (p<0.05. We next examined the relationship between disulfiram dose and cocaine choices. Disulfiram dose (mg/kg bodyweight was negatively correlated with number of choices for cocaine (p<0.05. Disulfiram also enhanced cocaine-induced increases in cardiovascular measures (p's<0.05-0.01. CONCLUSIONS: Disulfiram's impact on the reinforcing effects of cocaine depends on dose relative to body weight. Our results suggest that the use of weight-based medication doses would produce more reliable effects, consistent with weight-based dosing used in pediatrics and in preclinical research. TRIAL REGISTRATION: Clinicaltrials.gov NCT00729300.

  12. The Impact of Disulfiram Treatment on the Reinforcing Effects of Cocaine: A Randomized Clinical Trial

    Science.gov (United States)

    Haile, Colin N.; De La Garza, Richard; Mahoney, James J.; Nielsen, David A.; Kosten, Thomas R.; Newton, Thomas F.

    2012-01-01

    Background Clinical trials indicate that disulfiram (250 mg/d) reduces cocaine use, though one study found that treatment with lower doses of disulfiram (62.5 and 125 mg/d) increased cocaine use. We conducted the present study to better understand how disulfiram alters the reinforcing effects of cocaine in cocaine users. Methods Seventeen non-treatment seeking, cocaine-dependent volunteers participated in this double-blind, placebo-controlled, laboratory-based study. A cross-over design was utilized in which participants received placebo in one phase and disulfiram (250 mg/d) in the other. Following three days of study medication participants completed two choice sessions. In one they made 10 choices between receiving an intravenous infusion of saline or money that increased in value (US$ 0.05–16) and in the other cocaine (20 mg) or money. Results Participants chose cocaine more than saline under both disulfiram and placebo conditions (p<0.05). Unexpectedly, disulfiram increased both the number of cocaine and saline infusion choices (p<0.05). We next examined the relationship between disulfiram dose and cocaine choices. Disulfiram dose (mg/kg bodyweight) was negatively correlated with number of choices for cocaine (p<0.05). Disulfiram also enhanced cocaine-induced increases in cardiovascular measures (p's<0.05–0.01). Conclusions Disulfiram's impact on the reinforcing effects of cocaine depends on dose relative to body weight. Our results suggest that the use of weight-based medication doses would produce more reliable effects, consistent with weight-based dosing used in pediatrics and in preclinical research. Trial Registration Clinicaltrials.gov NCT00729300 PMID:23144826

  13. Electrophysiological characteristics of paraventricular thalamic (PVT) neurons in response to cocaine and cocaine- and amphetamine-regulated transcript (CART).

    Science.gov (United States)

    Yeoh, Jiann Wei; James, Morgan H; Graham, Brett A; Dayas, Christopher V

    2014-01-01

    Recent work has established that the paraventricular thalamus (PVT) is a central node in the brain reward-seeking pathway. This role is mediated in part through projections from hypothalamic peptide transmitter systems such as cocaine- and amphetamine-regulated transcript (CART). Consistent with this proposition, we previously found that inactivation of the PVT or infusions of CART into the PVT suppressed drug-seeking behavior in an animal model of contingent cocaine self-administration. Despite this work, few studies have assessed how the basic physiological properties of PVT neurons are influenced by exposure to drugs such as cocaine. Further, our previous work did not assess how infusions of CART, which we found to decrease cocaine-seeking, altered the activity of PVT neurons. In the current study we address these issues by recording from anterior PVT (aPVT) neurons in acutely prepared brain slices from cocaine-treated (15 mg/ml, n = 8) and saline-treated (control) animals (n = 8). The excitability of aPVT neurons was assessed by injecting a series of depolarizing and hyperpolarizing current steps and characterizing the resulting action potential (AP) discharge properties. This analysis indicated that the majority of aPVT neurons exhibit tonic firing (TF), and initial bursting (IB) consistent with previous studies. However, we also identified PVT neurons that exhibited delayed firing (DF), single spiking (SS) and reluctant firing (RF) patterns. Interestingly, cocaine exposure significantly increased the proportion of aPVT neurons that exhibited TF. We then investigated the effects of CART on excitatory synaptic inputs to aPVT neurons. Application of CART significantly suppressed excitatory synaptic drive to PVT neurons in both cocaine-treated and control recordings. This finding is consistent with our previous behavioral data, which showed that CART signaling in the PVT negatively regulates drug-seeking behavior. Together, these studies suggest that cocaine

  14. Electrophysiological characteristics of paraventricular thalamic (PVT) neurons in response to cocaine and cocaine- and amphetamine-regulated transcript (CART)

    Science.gov (United States)

    Yeoh, Jiann Wei; James, Morgan H.; Graham, Brett A.; Dayas, Christopher V.

    2014-01-01

    Recent work has established that the paraventricular thalamus (PVT) is a central node in the brain reward-seeking pathway. This role is mediated in part through projections from hypothalamic peptide transmitter systems such as cocaine- and amphetamine-regulated transcript (CART). Consistent with this proposition, we previously found that inactivation of the PVT or infusions of CART into the PVT suppressed drug-seeking behavior in an animal model of contingent cocaine self-administration. Despite this work, few studies have assessed how the basic physiological properties of PVT neurons are influenced by exposure to drugs such as cocaine. Further, our previous work did not assess how infusions of CART, which we found to decrease cocaine-seeking, altered the activity of PVT neurons. In the current study we address these issues by recording from anterior PVT (aPVT) neurons in acutely prepared brain slices from cocaine-treated (15 mg/ml, n = 8) and saline-treated (control) animals (n = 8). The excitability of aPVT neurons was assessed by injecting a series of depolarizing and hyperpolarizing current steps and characterizing the resulting action potential (AP) discharge properties. This analysis indicated that the majority of aPVT neurons exhibit tonic firing (TF), and initial bursting (IB) consistent with previous studies. However, we also identified PVT neurons that exhibited delayed firing (DF), single spiking (SS) and reluctant firing (RF) patterns. Interestingly, cocaine exposure significantly increased the proportion of aPVT neurons that exhibited TF. We then investigated the effects of CART on excitatory synaptic inputs to aPVT neurons. Application of CART significantly suppressed excitatory synaptic drive to PVT neurons in both cocaine-treated and control recordings. This finding is consistent with our previous behavioral data, which showed that CART signaling in the PVT negatively regulates drug-seeking behavior. Together, these studies suggest that cocaine

  15. Self-administration of cocaine–remifentanil mixtures by monkeys: an isobolographic analysis

    Science.gov (United States)

    Wang, Zhixia; Vasterling, Theresa; Tallarida, Ronald

    2009-01-01

    Rationale Abuse of mixtures of stimulants and opioids (“speedball”) is common. Although this combination has been studied in the laboratory, conclusions about the nature of the cocaine/opioid interaction have been mixed. Objectives The objectives of the present experiment were to allow monkeys to self-administer mixtures of cocaine and the μ opioid agonist remifentanil and to quantify the interaction using the isobolographic approach. Our hypothesis was that the drugs would be super-additive in their reinforcing effects. Materials and methods Rhesus monkeys (n = 5) prepared with i.v. catheters were allowed to self-administer cocaine or saline under a progressive-ratio schedule. When responding was stable, doses of cocaine or remifentanil were made available in test sessions. Next, mixtures of doses of the drugs were tested over a range of doses in 1:1, 1:2, and 2:1 ratios of their ED50s. Results were analyzed using isobolographic techniques. Results Both drugs alone and all drug mixtures functioned as positive reinforcers in a dose-related manner. Cocaine maintained more responding at maximum than did remifentanil, i.e., was a stronger reinforcer. The experimentally determined equi-effective dose for the 1:1 and 1:2 cocaine/remifentanil mixtures tended toward super-additivity, but the difference from additivity did not achieve statistical significance. The 2:1 mixture was super-additive. Maximum responding maintained by the mixtures was higher than that maintained by remifentanil but not different from cocaine. Conclusions Combinations of cocaine and remifentanil can be additive or super-additive as positive reinforcers, depending on proportions of each. Interactions between stimulants and opioids may contribute to the abuse of these mixtures. PMID:18461311

  16. d-Cycloserine combined with cue exposure therapy fails to attenuate subjective and physiological craving in cocaine dependence

    Science.gov (United States)

    Santa Ana, Elizabeth J.; Prisciandaro, James J.; Saladin, Michael E.; McRae-Clark, Aimee L.; Shaftman, Stephanie R.; Nietert, Paul J.; Brady, Kathleen T.

    2014-01-01

    Background Based on preclinical studies showing that the partial N-methyl-d-aspartate (NMDA) agonist d-cycloserine (DCS) facilitates extinction of cocaine self-administration and cocaine-induced conditioned place preference, we evaluated whether 50 mg of DCS would reduce craving to cocaine cues when combined with cue exposure (CE) in cocaine dependent humans. Methods In this double-blind placebo-controlled pilot study, 47 cocaine dependent participants were randomized to DCS or placebo (PBO), plus CE. Participants received DCS or PBO 30 minutes prior to two CE sessions, conducted one day apart. Craving and heart rate was assessed prior to CE sessions, during CE trials, and after CE trials. These measures were assessed again at a 1-week follow-up (session 3) after the second CE session. Results DCS failed to significantly attenuate cocaine cue reactivity based on subjective craving and physiological reactivity (heart rate) compared to PBO. The CE protocol, consisting of repeated exposure to drug cues combined with skills training, resulted in extinction to cocaine cues as suggested by decreased craving within and between sessions in both treatment conditions. All participants exhibited elevated heart rate with repeated exposures, demonstrating a potentiation in heart rate between sessions. PMID:25808169

  17. Co-sensitivity to the incentive properties of palatable food and cocaine in rats; implications for co-morbid addictions.

    Science.gov (United States)

    Levy, AnneMarie; Salamon, Avi; Tucci, Mark; Limebeer, Cheryl L; Parker, Linda A; Leri, Francesco

    2013-09-01

    Several lines of evidence suggest that there may be a shared vulnerability to acquire behaviors motivated by strong incentive stimuli. Non-food restricted male Sprague-Dawley rats (n = 78) underwent place conditioning with Oreos, and were subsequently tested on cocaine self-administration (SA) on fixed and progressive ratios, as well as extinction and reinstatement by cocaine primes and by consumption of Oreos. Although there was a group preference for the Oreo-paired compartment, at the individual level some rats (69%) displayed a preference and others did not. In cocaine SA, 'preference' rats achieved higher break points on a progressive ratio, and displayed greater responding during extinction and cocaine-induced reinstatement. Within the context of this study, Oreo-cocaine cross-reinstatement was not observed. In a control study, rats (n = 29) conditioned with a less palatable food (rice cakes) also displayed individual differences in place preference, but not on subsequent cocaine tests. These findings indicate that there is a relationship between incentive learning promoted by palatable foods and by cocaine. This supports the hypothesis that co-morbid food-drug addictions may result from a shared vulnerability to acquire behaviors motivated by strong incentives.

  18. The role of ventral and dorsal striatum mGluR5 in relapse to cocaine-seeking and extinction learning.

    Science.gov (United States)

    Knackstedt, Lori A; Trantham-Davidson, Heather L; Schwendt, Marek

    2014-01-01

    Cocaine addiction is a chronic, relapsing disease characterized by an inability to regulate drug-seeking behavior. Here we investigated the role of mGluR5 in the ventral and dorsal striatum in regulating cocaine-seeking following both abstinence and extinction. Animals underwent 2 weeks of cocaine self-administration followed by 3 weeks of home-cage abstinence. Animals were then reintroduced to the operant chamber for a context-induced relapse test, followed by 7-10 days of extinction training. Once responding was extinguished, cue-primed reinstatement test was conducted. Both drug-seeking tests were conducted in the presence of either mGluR5 negative allosteric modulator, MTEP or vehicle infused into either the nucleus accumbens (NA) core or dorsolateral striatum (dSTR). We found that MTEP infused in the NA core attenuated both context-induced relapse following abstinence and cue-primed reinstatement following extinction training. Blocking dSTR mGluR5 had no effect on context- or cue-induced cocaine-seeking. However, the intra-dSTR MTEP infusion on the context-induced relapse test day attenuated extinction learning for 4 days after the infusion. Furthermore, mGluR5 surface expression was reduced and LTD was absent in dSTR slices of animals undergoing 3 weeks of abstinence from cocaine but not sucrose self-administration. LTD was restored by bath application of VU-29, a positive allosteric modulator of mGluR5. Bath application of MTEP prevented the induction of LTD in dSTR slices from sucrose animals. Taken together, this data indicates that dSTR mGluR5 plays an essential role in extinction learning but not cocaine relapse, while NA core mGluR5 modulates drug-seeking following both extinction and abstinence from cocaine self-administration.

  19. Role of local self-administration in organization of local economy

    Directory of Open Access Journals (Sweden)

    I.V. Lytvynchuk

    2016-06-01

    Full Text Available The article researches the issues of studying the role of local self-administration in the organization of local economy taking into account the forms of management influence to satisfy the needs of administrative and territorial unit. On the base of previous scientific reseach generalization about the definition of local economy the article has summarized all the definitions. It has defined the structure of local economy which includes enterprises, organizations, and establishments of municipal property as well as enterprises, organizations, and establishments of not municipal property which activity is connected mostly with population servicing and can be included into local economies if an owner agrees; and the units established as a result of labour participation of citizens or bought at the expenses of their obtional contributions included into local economies if population and local authorities agree. The article considers normative regulation of local self-administration in Ukraine concerning the elements of its system as the entities which are given the authority to solve social, economic, management and industrial tasks of an administrative and territorial unit. The author views the practice of management by the units of municipal property of territorial societies. To satisfy the needs of society to the fullest the paper grounds the necessity to use the various forms of management influence by local authorities. Keywords: local economy; local self-administration; local self-administration authorities; territorial community

  20. Effects of Withania somnifera on oral ethanol self-administration in rats.

    Science.gov (United States)

    Peana, Alessandra T; Muggironi, Giulia; Spina, Liliana; Rosas, Michela; Kasture, Sanjay B; Cotti, Elisabetta; Acquas, Elio

    2014-10-01

    Recent evidence has shown that Withania somnifera Dunal (Ashwagandha or Indian ginseng), a herbal remedy used in traditional medicine, impairs morphine-elicited place conditioning. Here, we investigated the effect of W. somnifera roots extract (WSE) on motivation for drinking ethanol using operant self-administration paradigms. Wistar rats were trained to self-administer ethanol (10%) by nose-poking. The effects of WSE (25-75 mg/kg) were evaluated on acquisition and maintenance, on ethanol breakpoint under a progressive-ratio schedule of reinforcement and on the deprivation effect and reinstatement of seeking behaviours. Moreover, on the basis of the recent suggestion of an involvement of GABAB receptors in WSE central effects, we studied the interaction between WSE and GABAB ligands. The effect of WSE on saccharin (0.05%) oral self-administration was also tested. The results show that WSE reduced the acquisition, maintenance and breakpoint of ethanol self-administration. WSE also reduced the deprivation effect, reinstatement of ethanol-seeking behaviours and saccharin reinforcement. Furthermore, the GABAB receptor antagonist, phaclofen, counteracted the ability of WSE to impair the maintenance of ethanol self-administration. These findings show that WSE, by an action that may involve GABAB receptors, impairs motivation for drinking ethanol and suggest that further investigations should be performed to determine whether W. somnifera may represent a new approach for the management of alcohol abuse.

  1. [Sigmund Freud and cocaine].

    Science.gov (United States)

    Lebzeltern, G

    1983-11-11

    The basic tenet proposed by J. V. Scheidt states that the narcotic drug, cocaine played a role in the development of psychoanalysis which has been underestimated up to the present day. It is a fact that Freud himself took cocaine (in small doses) for about two years, and that he began his dream interpretation approximately ten years later. Scheidt believes that a long, unconscious conflict related to the cocaine-induced states of euphoria (ten years later) suddenly led to the beginnings of dream interpretation. The question to be answered now is: Why did this happen precisely in 1895? The foundations of psychoanalysis had already been laid, the application of the new method to the treatment of nervous disorders (heart complaints, train phobias, etc.) was certainly obvious. During this self-analysis it became necessary, first of all, to come to terms with the self-reproaches-which lay on the surface and were more accessible to consciousness-related to Freud's cocaine period (Fleischl-Marxow becomes addicted to cocaine, the most terrible night ever experienced, death of this friend, Freud's warning came too late). It was only when Freud has come to terms with this phase of his life that the road to the deepest part, the discovery of the Oedipus complex in the fall of 1897, was cleared.

  2. Disulfiram Attenuates Drug-Primed Reinstatement of Cocaine Seeking via Inhibition of Dopamine β-Hydroxylase

    Science.gov (United States)

    Schroeder, Jason P; Cooper, Debra A; Schank, Jesse R; Lyle, Megan A; Gaval-Cruz, Meriem; Ogbonmwan, Yvonne E; Pozdeyev, Nikita; Freeman, Kimberly G; Iuvone, P Michael; Edwards, Gaylen L; Holmes, Philip V; Weinshenker, David

    2010-01-01

    The antialcoholism medication disulfiram (Antabuse) inhibits aldehyde dehydrogenase (ALDH), which results in the accumulation of acetaldehyde upon ethanol ingestion and produces the aversive ‘Antabuse reaction' that deters alcohol consumption. Disulfiram has also been shown to deter cocaine use, even in the absence of an interaction with alcohol, indicating the existence of an ALDH-independent therapeutic mechanism. We hypothesized that disulfiram's inhibition of dopamine β-hydroxylase (DBH), the catecholamine biosynthetic enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons, underlies the drug's ability to treat cocaine dependence. We tested the effects of disulfiram on cocaine and food self-administration behavior and drug-primed reinstatement of cocaine seeking in rats. We then compared the effects of disulfiram with those of the selective DBH inhibitor, nepicastat. Disulfiram, at a dose (100 mg/kg, i.p.) that reduced brain NE by ∼40%, did not alter the response for food or cocaine on a fixed ratio 1 schedule, whereas it completely blocked cocaine-primed (10 mg/kg, i.p.) reinstatement of drug seeking following extinction. A lower dose of disulfiram (10 mg/kg) that did not reduce NE had no effect on cocaine-primed reinstatement. Nepicastat recapitulated the behavioral effects of disulfiram (100 mg/kg) at a dose (50 mg/kg, i.p.) that produced a similar reduction in brain NE. Food-primed reinstatement of food seeking was not impaired by DBH inhibition. Our results suggest that disulfiram's efficacy in the treatment of cocaine addiction is associated with the inhibition of DBH and interference with the ability of environmental stimuli to trigger relapse. PMID:20736996

  3. Dextromethorphan interactions with histaminergic and serotonergic treatments to reduce nicotine self-administration in rats.

    Science.gov (United States)

    Briggs, Scott A; Hall, Brandon J; Wells, Corinne; Slade, Susan; Jaskowski, Paul; Morrison, Margaret; Rezvani, Amir H; Rose, Jed E; Levin, Edward D

    2016-03-01

    Combining effective treatments with diverse mechanisms of action for smoking cessation may provide better therapy by targeting multiple points of control in the neural circuits underlying addiction. Previous research in a rat model has shown that dextromethorphan, which has α3β4 nicotinic and NMDA glutamatergic antagonist actions, significantly decreases nicotine self-administration. We have found in the rat model that the H1 histamine antagonist pyrilamine and the serotonin 5HT2C agonist lorcaserin also significantly reduce nicotine self-administration. The current studies were conducted to determine the interactive effects of dextromethorphan with pyrilamine and lorcaserin on nicotine self-administration in rats. Young adult female rats were fitted with jugular IV catheters and trained to self-administer a nicotine infusion dose of 0.03-mg/kg/infusion. In an initial dose-effect function study of dextromethorphan, we found a monotonic decrease in nicotine self-administration over a dose range of 1 to 30-mg/kg with the lowest effective dose of 3-mg/kg. Then, with two separate cohorts of rats, dextromethorphan (0, 3.3, and 10-mg/kg) interactions with pyrilamine (0, 4.43, and 13.3-mg/kg) were investigated as well as interactions with lorcaserin (0, 0.3125 and 0.625-mg/kg). In the pyrilamine-dextromethorphan interaction study, an acute dose of pyrilamine (13.3-mg/kg) as well as an acute dose of dextromethorphan caused a significant decrease in nicotine self-administration. There were mutually augmenting effects of these two drugs. The combination of dextromethorphan (10-mg/kg) and pyrilamine (13.3-mg/kg) significantly lowered nicotine self-administration relative to either 10-mg/kg of dextromethorphan alone (p<0.05) or 13.3-mg/kg of pyrilamine alone (p<0.0005). In the lorcaserin-dextromethorphan study, an acute dose of lorcaserin (0.312-mg/kg) as well as an acute dose of dextromethorphan (10-mg/kg) caused a significant decrease in nicotine self-administration

  4. The interactive effects of environmental enrichment and extinction interventions in attenuating cue-elicited cocaine-seeking behavior in rats.

    Science.gov (United States)

    Thiel, Kenneth J; Engelhardt, Ben; Hood, Lauren E; Peartree, Natalie A; Neisewander, Janet L

    2011-01-01

    Cues associated with cocaine can elicit craving and relapse. Attempts have been made to employ extinction therapy, which is aimed at attenuating the incentive motivational effects of cocaine cues, as a treatment for cocaine addiction; however, this approach has been largely unsuccessful perhaps due to the inability to extinguish all cues associated with cocaine use while in a clinic. Recently, environmental enrichment (EE) during abstinence has been proposed as a strategy to attenuate cue-elicited cocaine craving. The present study used an animal model to examine whether the utility of extinction toward attenuating cue-elicited cocaine-seeking behavior could be enhanced by also providing EE. All rats were trained to self-administer cocaine while housed in isolated conditions and then subsequently underwent 17 days of forced abstinence, during which they were either housed in pairs or under EE and they either received daily 1-h extinction sessions or similar handling without exposure to the self-administration environment. Following this intervention period, all rats were tested for cue-elicited cocaine-seeking behavior. To examine whether effects of these interventions persist, all rats were subsequently single-housed for an additional 7-day forced abstinence period, followed by a second test for cue-elicited cocaine-seeking behavior. We found that although daily extinction training and EE each attenuated subsequent cue-elicited cocaine-seeking behavior, the combined treatment of extinction training+EE completely prevented it. However, once these interventions were discontinued, their protective effects diminished. These findings suggest that combining behavioral therapy approaches may improve outcomes; however, future work is needed to improve the longevity of these strategies beyond their implementation.

  5. Escalation of i.v. cocaine intake in peri-adolescent vs. adult rats selectively bred for high (HiS) vs. low (LoS) saccharin intake.

    Science.gov (United States)

    Holtz, Nathan A; Carroll, Marilyn E

    2013-05-01

    Adolescence marks a period of increased vulnerability to the development of substance use disorders. High sweet preference is a genetically mediated behavioral trait that also predicts vulnerability to substances of abuse. Previous research has shown that while adolescent rats selectively bred for high (HiS) saccharin intake acquire cocaine self-administration at the same rate as adult HiS rats, adolescent rats bred for low saccharin intake (LoS) acquire cocaine self-administration faster than adult LoS rats. This study was conducted to investigate the interaction of the addiction vulnerability factors of peri-adolescence and saccharin preference on cocaine intake using an animal model of escalation of cocaine consumption over 6-h/day sessions. Peri-adolescent and adult HiS and LoS female rats self-administered i.v. cocaine (0.4 mg/kg/inf) during short-access (2-h/day) sessions for 2 days. Next, a long-access (6-h/day) period (LgA) commenced and lasted 16 days. Following LgA, session length was returned to 2-h/day for a second short access phase. LoS peri-adolescent rats escalated cocaine intake over the LgA period and consumed more drug than LoS adult rats; however, peri-adolescent and adult HiS rats consumed similar amounts of cocaine during this period. Additionally, adult HiS rats self-administered more cocaine than adult LoS rats during the LgA period, while there was no phenotypic difference between the rat lines during peri-adolescence for the LgA period. During the first short-access phase, peri-adolescent rats self-administered more cocaine than adult rats. These results emphasize the importance of adolescent drug abuse prevention by illustrating that phenotypic protection from addiction may not be expressed until adulthood.

  6. Cocaine and benzoylecgonine oral fluid on-site screening and confirmation.

    Science.gov (United States)

    Ellefsen, Kayla N; Concheiro, Marta; Pirard, Sandrine; Gorelick, David A; Huestis, Marilyn A

    2016-01-01

    Accurate on-site devices to screen for drug intake are critical for establishing whether an individual is driving under the influence of drugs (DUID); however, on-site oral fluid (OF) cocaine device performance is variable. We evaluated the performance of a newly developed benzoylecgonine (BE) test-strip for the Draeger® DrugTest 5000 device (20 µg/L cut-off) with equivalent cross reactivity for cocaine and BE. Ten cocaine users provided OF, collected with the Draeger cassette and Oral-Eze® and StatSure Saliva Sampler(TM) devices, up to 69 h following 25 mg intravenous cocaine administration. All screening results were confirmed by a validated two-dimensional-gas chromatography-mass spectrometry (2D-GC-MS) method for cocaine and/or BE. Cocaine test-strip median Tlast for screening only results was 6.5 h, and 6.5 h with Oral-Eze® and 4 h for StatSure OF confirmation for cocaine and/or BE at 1, 8, and 10 µg/L; sensitivity, specificity, and efficiency ranged from 85.5 to 100% and 83.3 to 100% for cocaine only confirmation at 8 and 10 µg/L. For the BE test-strip, median Tlast was 12.5 h for screening only and confirmation for cocaine and/or BE at all three cut-offs; sensitivity, specificity, and efficiency ranged from 85.5 to 97.5% and 78.4 to 97.4% with cocaine and/or BE confirmation at 8 and 10 µg/L cut-offs, respectively. The Draeger cocaine test-strip with cocaine only confirmation offers a useful option for monitoring the acute intoxication phase of DUID; additionally the BE test-strip with cocaine and/or BE confirmation increases the length of detection of cocaine intake for workplace drug testing, drug court, parole, pain management, drug treatment programs and both the acute cocaine intoxication and cocaine crash/fatigue phase of DUID. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Cocaine cardiomyopathy: A case report

    Directory of Open Access Journals (Sweden)

    Georgiev Antonio

    2014-12-01

    Full Text Available Cocaine is the second most common illicit drug used and the most frequent cause of drug related deaths. The use of cocaine is associated with both, acute and chronic complications, that may involve any system, but the most common system affected is cardiovascular one. Cocaine cardiomyopathy may result from the use of cocaine. This article presents a first case in Republic of Macedonia of 24-year-old male with reversible cocaine-related cardiomyopathy. Clinical presentation, laboratory, X-ray, ultrasound findings and treatment are reviewed.

  8. Anticonvulsants for cocaine dependence.

    Science.gov (United States)

    Minozzi, Silvia; Cinquini, Michela; Amato, Laura; Davoli, Marina; Farrell, Michael F; Pani, Pier Paolo; Vecchi, Simona

    2015-04-17

    Cocaine dependence is a major public health problem that is characterised by recidivism and a host of medical and psychosocial complications. Although effective pharmacotherapy is available for alcohol and heroin dependence, none is currently available for cocaine dependence, despite two decades of clinical trials primarily involving antidepressant, anticonvulsivant and dopaminergic medications. Extensive consideration has been given to optimal pharmacological approaches to the treatment of individuals with cocaine dependence, and both dopamine antagonists and agonists have been considered. Anticonvulsants have been candidates for use in the treatment of addiction based on the hypothesis that seizure kindling-like mechanisms contribute to addiction. To evaluate the efficacy and safety of anticonvulsants for individuals with cocaine dependence. We searched the Cochrane Drugs and Alcohol Group Trials Register (June 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, Issue 6), MEDLINE (1966 to June 2014), EMBASE (1988 to June 2014), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to June 2014), Web of Science (1991 to June 2014) and the reference lists of eligible articles. All randomised controlled trials and controlled clinical trials that focus on the use of anticonvulsant medications to treat individuals with cocaine dependence. We used the standard methodological procedures expected by The Cochrane Collaboration. We included a total of 20 studies with 2068 participants. We studied the anticonvulsant drugs carbamazepine, gabapentin, lamotrigine, phenytoin, tiagabine, topiramate and vigabatrin. All studies compared anticonvulsants versus placebo. Only one study had one arm by which the anticonvulsant was compared with the antidepressant desipramine. Upon comparison of anticonvulsant versus placebo, we found no significant differences for any of the efficacy and safety measures. Dropouts: risk ratio (RR) 0.95, 95

  9. 21 CFR 862.3250 - Cocaine and cocaine metabolite test system.

    Science.gov (United States)

    2010-04-01

    ... treatment of cocaine use or overdose. (b) Classification. Class II. ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cocaine and cocaine metabolite test system. 862... Test Systems § 862.3250 Cocaine and cocaine metabolite test system. (a) Identification. A cocaine and...

  10. Interest in self-administration of subcutaneous depot medroxyprogesterone acetate in the United States.

    Science.gov (United States)

    Upadhyay, Ushma D; Zlidar, Vera M; Foster, Diana Greene

    2016-10-01

    Subcutaneous depot medroxyprogesterone acetate (DMPA-SC) is a low-dose formulation of depot medroxyprogesterone acetate (DMPA) that nonmedical personnel can administer safely and effectively. We sought to determine United States women's interest in self-administration of DMPA-SC to understand whether such use can overcome barriers to contraceptive access. We analyzed survey data on contraceptive attitudes collected in March-July 2011 from 1592 women at 13 family planning and six abortion clinics throughout the US. A mixed-effects logistic regression model with random site effects examined the determinants of interest in self-administering DMPA-SC. Overall, 21% [95% confidence interval (CI): 19%-23%] of women reported interest in self-administration. A multivariable model found that women currently using DMPA (Adjusted Odds Ratio [AOR]=3.93, 95% CI: 2.37-6.53, p<.001) and women who previously used DMPA (AOR=1.71, 95% CI: 1.26-2.32, p<.001) were more likely to have an interest in DMPA-SC than those who never used it. Women reporting difficulty obtaining or refilling a prescription were almost twice as likely to have interest in DMPA-SC as women who reported no difficulty (AOR=1.99, 95% CI: 1.43-2.77, p<.001). Women surveyed at abortion sites were more likely to report interest in self-administration than women surveyed at family planning sites (AOR=1.55, 95% CI: 1.05-2.30, p<.05). Interest in DMPA-SC was primarily driven by a desire to eliminate unnecessary return visits to a facility for repeat injections. Offering women the option to self-administer DMPA-SC at home can expand access and tailor contraceptive provision to the needs of clients, thus supporting client-centered care. To the extent that self-administration may improve contraceptive continuation, DMPA-SC can prevent unintended pregnancies among women who discontinue DMPA use because of difficulty returning for repeat injections. There is substantial interest in self-administration of DMPA-SC among current

  11. Demand Curves for Hypothetical Cocaine in Cocaine-Dependent Individuals

    Science.gov (United States)

    Bruner, Natalie R.; Johnson, Matthew W.

    2013-01-01

    Rationale Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. Objectives This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Methods Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Results Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and Omax (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, Pmax, were significantly correlated with real-world cocaine use. Conclusions Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use. PMID:24217899

  12. Demand curves for hypothetical cocaine in cocaine-dependent individuals.

    Science.gov (United States)

    Bruner, Natalie R; Johnson, Matthew W

    2014-03-01

    Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks, drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and O max (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, P max, were significantly correlated with real-world cocaine use. Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use.

  13. The teratogenicity of cocaine.

    Science.gov (United States)

    Fantel, A G; Macphail, B J

    1982-08-01

    Pregnancy rats and mice received high doses of cocaine hydrochloride by intraperitoneal injection. Despite treatment periods which included most of organogenesis, no increase in congenital abnormalities was observed. Rats showed significant reductions in maternal and fetal weights as well as increased resorption frequencies. Fetal edema was also found. Mice showed only decreased fetal weights with no increase in malformations.

  14. Group I mGluR activation reverses cocaine-induced accumulation of calcium-permeable AMPA receptors in nucleus accumbens synapses via a protein kinase C-dependent mechanism.

    Science.gov (United States)

    McCutcheon, James E; Loweth, Jessica A; Ford, Kerstin A; Marinelli, Michela; Wolf, Marina E; Tseng, Kuei Y

    2011-10-12

    Following prolonged withdrawal from extended access cocaine self-administration in adult rats, high conductance Ca2+ -ermeable AMPA receptors (CP-AMPARs) accumulate in nucleus accumbens (NAc) synapses and mediate the expression of "incubated" cue-induced cocaine craving. Using patch-clamp recordings from NAc slices prepared after extended access cocaine self-administration and >45 d of withdrawal, we found that group I metabotropic glutamate receptor (mGluR) stimulation using 3,5-dihydroxyphenylglycine (DHPG; 50 μm) rapidly eliminates the postsynaptic CP-AMPAR contribution to NAc synaptic transmission. This is accompanied by facilitation of Ca2+ -impermeable AMPAR (CI-AMPAR)-mediated transmission, suggesting that DHPG may promote an exchange between CP-AMPARs and CI-AMPARs. In saline controls, DHPG also reduced excitatory transmission but this occurred through a CB1 receptor-dependent presynaptic mechanism rather than an effect on postsynaptic AMPARs. Blockade of CB1 receptors had no significant effect on the alterations in AMPAR transmission produced by DHPG in the cocaine group. Interestingly, the effect of DHPG in the cocaine group was mediated by mGluR1 whereas its effect in the saline group was mediated by mGluR5. These results indicate that regulation of synaptic transmission in the NAc is profoundly altered after extended access cocaine self-administration and prolonged withdrawal. Furthermore, they suggest that activation of mGluR1 may represent a potential strategy for reducing cue-induced cocaine craving in abstinent cocaine addicts.

  15. The effects of naltrexone on cadmium-induced increases in oral ethanol self-administration.

    Science.gov (United States)

    Nation, J R; Horger, B A; Pugh, C K; Bratton, G R; Rowe, L D

    1990-01-01

    Adult male rats were exposed to a standard laboratory diet (N = 20), or an adulterated diet containing 100 ppm added cadmium (N = 20), for 60 days. On Day 61, half the animals from each dietary condition received subcutaneous implants of two 30 mg naltrexone pellets, and the remaining half the animals received identical implants of 30 mg placebo pellets. One week later, animals from groups created by this interaction (Groups Control-Placebo, Control-Naltrexone, Cadmium-Placebo, Cadmium-Naltrexone) were tested in an ethanol self-administration paradigm that presented a 10% ethanol solution (v/v) in both a choice and nonchoice format. The results indicated that cadmium exposure increased the oral self-administration of ethanol in the choice setting where water was offered as an alternative, and the opiate antagonist naltrexone failed to attenuate this effect.

  16. Emotion recognition during cocaine intoxication.

    Science.gov (United States)

    Kuypers, K P C; Steenbergen, L; Theunissen, E L; Toennes, S W; Ramaekers, J G

    2015-11-01

    Chronic or repeated cocaine use has been linked to impairments in social skills. It is not clear whether cocaine is responsible for this impairment or whether other factors, like polydrug use, distort the observed relation. We aimed to investigate this relation by means of a placebo-controlled experimental study. Additionally, associations between stressor-related activity (cortisol, cardiovascular parameters) induced by the biological stressor cocaine, and potential cocaine effects on emotion recognition were studied. Twenty-four healthy recreational cocaine users participated in this placebo-controlled within-subject study. Participants were tested between 1 and 2 h after treatment with oral cocaine (300 mg) or placebo. Emotion recognition of low and high intensity expressions of basic emotions (fear, anger, disgust, sadness, and happiness) was tested. Findings show that cocaine impaired recognition of negative emotions; this was mediated by the intensity of the presented emotions. When high intensity expressions of Anger and Disgust were shown, performance under influence of cocaine 'normalized' to placebo-like levels while it made identification of Sadness more difficult. The normalization of performance was most notable for participants with the largest cortisol responses in the cocaine condition compared to placebo. It was demonstrated that cocaine impairs recognition of negative emotions, depending on the intensity of emotion expression and cortisol response.

  17. Oxycodone physical dependence and its oral self-administration in C57BL/6J mice.

    Science.gov (United States)

    Enga, Rachel M; Jackson, Asti; Damaj, M Imad; Beardsley, Patrick M

    2016-10-15

    Abuse of prescription opioids, such as oxycodone, has markedly increased in recent decades. While oxycodone's antinociceptive effects have been detailed in several preclinical reports, surprisingly few preclinical reports have elaborated its abuse-related effects. This is particularly surprising given that oxycodone has been in clinical use since 1917. In a novel oral operant self-administration procedure, C57BL/6J mice were trained to self-administer water before introducing increasing concentrations of oxycodone (0.056-1.0mg/ml) under post-prandial conditions during daily, 3-h test sessions. As the concentration of oxycodone increased, the numbers of deliveries first increased, then decreased in an inverted U-shape fashion characteristic of the patterns of other drugs self-administered during limited access conditions. After post-prandial conditions were removed, self-administration at the highest concentration was maintained suggesting oral oxycodone served as a positive reinforcer. In other mice, using a novel regimen of physical dependence, mice were administered increasing doses of oxycodone (9.0-33.0mg/kg, s.c.) over 9 days, challenged with naloxone (0.1-10.0mg/kg, s.c.), and then observed for 30min. Naloxone dose-dependently increased the observed number of somatic signs of withdrawal, suggesting physical dependence of oxycodone was induced under this regimen. This is the first report demonstrating induction of oral operant self-administration of oxycodone and dose-dependent precipitations of oxycodone withdrawal in C57BL/6J mice. The use of oral operant self-administration as well as the novel physical dependence regimen provides useful approaches to further examine the abuse- and dependence-related effects of this highly abused prescription opioid.

  18. Validity of building characteristics and dorm dampness obtained in a self-administrated questionnaire

    DEFF Research Database (Denmark)

    Sun, Y.X.; Sundell, Jan; Zhang, Y.F.

    2007-01-01

    A self-administrated questionnaire used in a cross-sectional study on associations between environmental factors and allergies was validated by building inspections and physical measurements. The agreement was good between the reports from occupants and inspectors regarding technical...... characteristics, such as type of surface materials etc., but a poor to slight agreement (kappa... damages, occupants reports seem more relevant than inspector reports, in a study of health....

  19. Tobacco particulate matter self-administration in rats: differential effects of tobacco type.

    Science.gov (United States)

    Brennan, Katharine A; Crowther, Alex; Putt, Fraser; Roper, Vicky; Waterhouse, Uta; Truman, Penelope

    2015-03-01

    Nicotine self-administration in rats is the most widely used animal model of tobacco dependence. There is increasing evidence, however, that non-nicotinic constituents in smoke contribute to addiction and that different tobacco products contain varying levels of these constituents. The present study firstly sought to compare self-administration of pure nicotine to tobacco particulate matter (TPM) to determine if there were differences in reward-efficacy attributable to the non-nicotine constituents. Secondly, cigarette and roll-your-own (RYO) TPM groups were included and compared to determine whether different formulations of non-nicotinic constituents could impact reward. Briefly, male Sprague Dawley rats were implanted with indwelling jugular catheters for self-administration (n = 76). The reinforcing efficacy of infusions of nicotine (0.0 or 30.0 μg/kg/infusion) versus cigarette/RYO TPM (with matched nicotine content) was determined using spontaneous acquisition of self-administration on a fixed ratio schedule. The progressive ratio schedule was then employed to determine the motivation to receive each drug and within-subject dose-response curves were also produced (7.5, 15.0, 30.0 and 60.0 μg/kg/infusion nicotine). The main finding was that the RYO TPM was more reinforcing and produced a different profile of reward-related behaviour compared with both the nicotine and the cigarette TPM groups. The conclusions were that non-nicotinic components have a role in tobacco dependence and that some tobacco products could have higher abuse liability, irrespective of nicotine levels.

  20. Exposure of adolescent mice to 3,4-methylenedioxypyrovalerone increases the psychostimulant, rewarding and reinforcing effects of cocaine in adulthood.

    Science.gov (United States)

    López-Arnau, R; Luján, M A; Duart-Castells, L; Pubill, D; Camarasa, J; Valverde, O; Escubedo, E

    2017-05-01

    3,4-Methylenedioxypyrovalerone (MDPV) is a synthetic cathinone with powerful psychostimulant effects. It selectively inhibits the dopamine transporter (DAT) and is 10-50-fold more potent as a DAT blocker than cocaine, suggesting a high abuse liability. The main objective of the present study was to assess the consequences of an early (adolescence) MDPV exposure on the psychostimulant, rewarding and reinforcing effects induced by cocaine in adult mice. Twenty-one days after MDPV pretreatment (1.5 mg·kg(-1) , s.c., twice daily for 7 days), adult mice were tested with cocaine, using locomotor activity, conditioned place preference and self-administration (SA) paradigms. In parallel, dopamine D2 receptor density and the expression of c-Fos and ΔFosB in the striatum were determined. MDPV treatment enhanced the psychostimulant and conditioning effects of cocaine. Acquisition of cocaine SA was unchanged in mice pretreated with MDPV, whereas the breaking point achieved under a progressive ratio programme and reinstatement after extinction were higher in this group of mice. MDPV decreased D2 receptor density but increased ΔFosB expression three-fold. As expected, acute cocaine increased c-Fos expression, but MDPV pretreatment negatively influenced its expression. ΔFosB accumulation declined during MDPV withdrawal, although it remained elevated in adult mice when tested for cocaine effects. MDPV exposure during adolescence induced long-lasting adaptive changes related to enhanced responsiveness to cocaine in the adult mice that seems to lead to a higher vulnerability to cocaine abuse. This particular behaviour correlated with increased expression of ΔFosB. © 2017 The British Pharmacological Society.

  1. Operant alcohol self-administration in dependent rats: focus on the vapor model.

    Science.gov (United States)

    Vendruscolo, Leandro F; Roberts, Amanda J

    2014-05-01

    Alcoholism (alcohol dependence) is characterized by a compulsion to seek and ingest alcohol (ethanol), loss of control over intake, and the emergence of a negative emotional state during withdrawal. Animal models are critical in promoting our knowledge of the neurobiological mechanisms underlying alcohol dependence. Here, we review the studies involving operant alcohol self-administration in rat models of alcohol dependence and withdrawal with the focus on the alcohol vapor model. In 1996, the first articles were published reporting that rats made dependent on alcohol by exposure to alcohol vapors displayed increased operant alcohol self-administration during acute withdrawal compared with nondependent rats (i.e., not exposed to alcohol vapors). Since then, it has been repeatedly demonstrated that this model reliably produces physical and motivational symptoms of alcohol dependence. The functional roles of various systems implicated in stress and reward, including opioids, dopamine, corticotropin-releasing factor (CRF), glucocorticoids, neuropeptide Y (NPY), γ-aminobutyric acid (GABA), norepinephrine, and cannabinoids, have been investigated in the context of alcohol dependence. The combination of models of alcohol withdrawal and dependence with operant self-administration constitutes an excellent tool to investigate the neurobiology of alcoholism. In fact, this work has helped lay the groundwork for several ongoing clinical trials for alcohol dependence. Advantages and limitations of this model are discussed, with an emphasis on what future directions of great importance could be.

  2. Development of an opioid self-administration assay to study drug seeking in zebrafish.

    Science.gov (United States)

    Bossé, Gabriel D; Peterson, Randall T

    2017-09-29

    The zebrafish (Danio rerio) has become an excellent tool to study mental health disorders, due to its physiological and genetic similarity to humans, ease of genetic manipulation, and feasibility of small molecule screening. Zebrafish have been shown to exhibit characteristics of addiction to drugs of abuse in non-contingent assays, including conditioned place preference, but contingent assays have been limited to a single assay for alcohol consumption. Using inexpensive electronic, mechanical, and optical components, we developed an automated opioid self-administration assay for zebrafish, enabling us to measure drug seeking and gain insight into the underlying biological pathways. Zebrafish trained in the assay for five days exhibited robust self-administration, which was dependent on the function of the μ-opioid receptor. In addition, a progressive ratio protocol was used to test conditioned animals for motivation. Furthermore, conditioned fish continued to seek the drug despite an adverse consequence and showed signs of stress and anxiety upon withdrawal of the drug. Finally, we validated our assay by confirming that self-administration in zebrafish is dependent on several of the same molecular pathways as in other animal models. Given the ease and throughput of this assay, it will enable identification of important biological pathways regulating drug seeking and could lead to the development of new therapeutic molecules to treat addiction. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Effect of chronic pain on fentanyl self-administration in mice.

    Directory of Open Access Journals (Sweden)

    Carrie L Wade

    Full Text Available The development of opioid addiction in subjects with established chronic pain is an area that is poorly understood. It is critically important to clearly understand the neurobiology associated with propensity toward conversion to addiction under conditions of chronic pain. To pose the question whether the presence of chronic pain influences motivation to self-administer opioids for reward, we applied a combination of rodent models of chronic mechanical hyperalgesia and opioid self-administration. We studied fentanyl self-administration in mice under three conditions that induce chronic mechanical hyperalgesia: inflammation, peripheral nerve injury, and repeated chemotherapeutic injections. Responding for fentanyl was compared among these conditions and their respective standard controls (naïve condition, vehicle injection or sham surgery. Acquisition of fentanyl self-administration behavior was reduced or absent in all three conditions of chronic hyperalgesia relative to control mice with normal sensory thresholds. To control for potential impairment in ability to learn the lever-pressing behavior or perform the associated motor tasks, all three groups were evaluated for acquisition of food-maintained responding. In contrast to the opioid, chronic hyperalgesia did not interfere with the reinforcing effect of food. These studies indicate that the establishment of chronic hyperalgesia is associated with reduced or ablated motivation to seek opioid reward in mice.

  4. CREB activity in dopamine D1 receptor expressing neurons regulates cocaine-induced behavioral effects

    Directory of Open Access Journals (Sweden)

    Ainhoa eBilbao

    2014-06-01

    Full Text Available IIt is suggested that striatal cAMP responsive element binding protein (CREB regulates sensitivity to psychostimulants. To test the cell-specificity of this hypothesis we examined the effects of a dominant-negative CREB protein variant expressed in dopamine receptor D1 (D1R neurons on cocaine-induced behaviors. A transgenic mouse strain was generated by pronuclear injection of a BAC-derived transgene harboring the A-CREB sequence under the control of the D1R gene promoter. Compared to wild-type, drug-naïve mutants showed moderate alterations in gene expression, especially a reduction in basal levels of activity-regulated transcripts such as Arc and Egr2. Drug-naïve mutants showed moderate alterations in gene expression, most prominently a reduction in basal levels of activity-regulated transcripts such as Arc and Egr2, when compared to wild-type controls. The behavioral responses to cocaine were elevated in mutant mice. Locomotor activity after acute treatment, psychomotor sensitization after intermittent drug injections and the conditioned locomotion after saline treatment were increased compared to wild-type littermates. Transgenic mice had significantly higher cocaine conditioned place preference, displayed normal extinction of the conditioned preference, but showed an augmented cocaine-seeking response following priming-induced reinstatement. This enhanced cocaine-seeking response was associated with increased levels of activity-regulated transcripts and prodynorphin. The primary reinforcing effects of cocaine were not altered in the mutant mice as they did not differ from wild-type in cocaine self-administration under a fixed ratio schedule at the training dose. Collectively, our data indicate that expression of a dominant-negative CREB variant exclusively in neurons expressing D1R is sufficient to recapitulate the previously reported behavioral phenotypes associated with virally expressed dominant-negative CREB.

  5. Conditioned stress prevents cue-primed cocaine reinstatement only in stress-responsive rats.

    Science.gov (United States)

    Hadad, Natalie A; Wu, Lizhen; Hiller, Helmut; Krause, Eric G; Schwendt, Marek; Knackstedt, Lori A

    2016-07-01

    Neurobiological mechanisms underlying comorbid posttraumatic stress disorder (PTSD) and cocaine use disorder (CUD) are unknown. We aimed to develop an animal model of PTSD + CUD to examine the neurobiology underlying cocaine-seeking in the presence of PTSD comorbidity. Rats were exposed to cat urine once for 10-minutes and tested for anxiety-like behaviors one week later. Subsequently, rats underwent long-access (LgA) cocaine self-administration and extinction training. Rats were re-exposed to the trauma context and then immediately tested for cue-primed reinstatement of cocaine-seeking. Plasma and brains were collected afterwards for corticosterone assays and real-time qPCR analysis. Urine-exposed (UE; n = 23) and controls not exposed to urine (Ctrl; n = 11) did not differ in elevated plus maze behavior, but UE rats displayed significantly reduced habituation of the acoustic startle response (ASR) relative to Ctrl rats. A median split of ASR habituation scores was used to classify stress-responsive rats. UE rats (n = 10) self-administered more cocaine on Day 1 of LgA than control rats (Ctrl + Coc; n = 8). Re-exposure to the trauma context prevented cocaine reinstatement only in stress-responsive rats. Ctrl + Coc rats had lower plasma corticosterone concentrations than Ctrls, and decreased gene expression of corticotropin releasing hormone (CRH) and Glcci1 in the hippocampus. Rats that self-administered cocaine displayed greater CRH expression in the amygdala that was independent of urine exposure. While we did not find that cat urine exposure induced a PTSD-like phenotype in our rats, the present study underscores the need to separate stressed rats into cohorts based on anxiety-like behavior in order to study individual vulnerability to PTSD + CUD.

  6. The ketamine-like compound methoxetamine substitutes for ketamine in the self-administration paradigm and enhances mesolimbic dopaminergic transmission.

    Science.gov (United States)

    Mutti, Anna; Aroni, Sonia; Fadda, Paola; Padovani, Laura; Mancini, Laura; Collu, Roberto; Muntoni, Anna Lisa; Fattore, Liana; Chiamulera, Cristiano

    2016-06-01

    Recently, an increasing number of emergency cases due to a novel ketamine-like drug, methoxetamine (MXE), were reported in several countries. However, very little is known about the neuropsychopharmacological and reinforcing profile of this compound. Our study aims to investigate the effects of MXE on self-administration (SA) behaviour in comparison to ketamine and on dopaminergic transmission. A SA substitution study was performed in male rats trained to intravenously (IV) self-administer ketamine. At responding stability, rats were exposed to sequential phases of MXE substitution at different dosages (starting from 0.5 and then decreasing to 0.25 and 0.125 mg/kg). Standard electrophysiological techniques were used to record changes in firing activities of ventral tegmental area (VTA) dopamine neurons projecting to the nucleus accumbens (NAc) shell after acute injection of cumulative doses of MXE (0.031-0.5 mg/kg IV). Finally, in vivo microdialysis was performed in freely moving rats to evaluate the effect of acute MXE administration (0.125, 0.25 and 0.5 mg/kg IV) on dopamine release in the NAc shell. MXE 0.125 and 0.25 mg/kg, but not 0.5 mg/kg, substituted for ketamine SA. MXE also induced a dose-dependent stimulation of firing rate (p < 0.0001) and burst firing (p < 0.05) of NAc-projecting VTA dopamine neurons. Consistently, MXE significantly (p < 0.05) increased dopamine extracellular levels in the NAc shell at 0.5 and 0.25 mg/kg with different time onsets, i.e. at 40 and 100 min, respectively. This study, while confirming the reinforcing effects of MXE, highlights an electrophysiological and neurochemical profile predictive of its addictive properties.

  7. Tips for Teens: The Truth about Cocaine

    Science.gov (United States)

    ... and intense cravings.Cocaine may give users atemporary illusion of power and energy,but it often leaves ... of dollars on cocaine each week. Stay in control. Cocaine impairs your judgment, which may lead to ...

  8. Enhanced Choice for Viewing Cocaine Pictures in Cocaine Addiction

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, S.J.; Goldstein, R.; Moeller, S.J.; Maloney, T. Parvaz, M.A.; Dunning, J.P.; Alia-Klein, N.; Woicik, P.A.; Hajcak, G.; Telang, F.; Wang, G.-J.; Volkow, N.D.; Goldstein, R.Z.

    2009-02-01

    Individuals with cocaine use disorder (CUD) chose cocaine over nondrug rewards. In two newly designed laboratory tasks with pictures, we document this modified choice outside of a cocaine administration paradigm. Choice for viewing cocaine, pleasant, unpleasant, or neutral pictures-under explicit contingencies (choice made between two fully visible side-by-side images) and under more implicit contingencies (selections made between pictures hidden under flipped-over cards)-was examined in 20 CUD and 20 matched healthy control subjects. Subjects also provided self-reported ratings of each picture's pleasantness and arousal. Under both contingencies, CUD subjects chose to view more cocaine pictures than control subjects, group differences that were not fully explained by the self-reported picture ratings. Furthermore, whereas CUD subjects choice for viewing cocaine pictures exceeded choice for viewing unpleasant pictures (but did not exceed choice for viewing pleasant pictures, in contrast to their self-reported ratings), healthy control subjects avoided viewing cocaine pictures as frequently as, or even more than, unpleasant pictures. Finally, CUD subjects with the most cocaine viewing selections, even when directly compared with selections of the pleasant pictures, also reported the most frequent recent cocaine use. Enhanced drug-related choice in cocaine addiction can be demonstrated even for nonpharmacologic (pictorial) stimuli. This choice, which is modulated by alternative stimuli, partly transcends self-reports (possibly indicative of a disconnect in cocaine addiction between self-reports and objective behavior) to provide an objective marker of addiction severity. Neuroimaging studies are needed to establish the neural underpinnings of such enhanced cocaine-related choice.

  9. Sex-specific attenuation of impulsive action by progesterone in a go/no-go task for cocaine in rats.

    Science.gov (United States)

    Swalve, Natashia; Smethells, John R; Younk, Rebecca; Mitchell, Jared; Dougen, Ben; Carroll, Marilyn E

    2017-10-10

    Previous work indicated that progesterone (PRO) reduced impulsive choice for cocaine in female but not male rats (Smethells et al. Psychopharmacology 233:2999-3008, 2016). Impulsive action, typically measured by responding for a reinforcer during a signaled period of nonavailability of natural reinforcers, predicts initiation and escalation of drug use in animals and humans. The present study examined impulsive action for cocaine using PRO in male and female rats trained on a go/no-go task. Rats were trained on a go/no-go task to respond for cocaine infusions (0.4 mg/kg/inf). During the "go" component, responding was reinforced on a VI 30-s schedule, whereas during the "no-go" component, withholding a response was reinforced on a differential reinforcement of other behavior (DRO) 30-s schedule. A response during the no-go component resets the DRO timer and served as a measure of impulsive action. After baseline responding was established, rats were pretreated with vehicle (VEH) or PRO (0.5 mg/kg), and DRO resets and responding during the go component for cocaine were compared in males vs. females. DRO resets were significantly lower following PRO treatment compared to VEH in female, but not male, rats. Response rates and overall infusions during the go component were not significantly altered by PRO in either females or males. Treatment with PRO resulted in a sex-specific reduction in impulsive action for cocaine, while not affecting cocaine self-administration.

  10. Cocaine cues retain silent traces of an excitatory history after conversion into conditioned inhibitors: 'the ghost in the addict'.

    Science.gov (United States)

    Weiss, Stanley J; Kearns, David N

    2016-04-01

    The present experiment investigated the extent to which the A+/AB- conditioned inhibition procedure could counteract an excitatory drug-related conditioning history. In two groups of rats, a light stimulus was established as a signal for the absence of cocaine. For the History group, the light had previously been a discriminative stimulus (S) that occasioned cocaine self-administration and could thus be classified as a cocaine excitor. In comparison, the No-History group first encountered the light during conditioned inhibition training. During conditioned inhibition training, both groups self-administered cocaine during tone as well as during click Ss, whereas drug seeking was eliminated in click-plus-light, wherein cocaine was not available (A+/AB-). Drug seeking was essentially eliminated in both groups. Nevertheless, on a summation test the light reduced cocaine seeking occasioned by the tone S by 95% in the No-History group, but by less than 50% in the History group. This summation test result showed that the effects of a drug-related history persisted even after the light was converted into an effective conditioned inhibitor on the training baseline through the powerful A+/AB- procedure. Future research should seek procedures that produce even stronger conditioned inhibition that eliminates such residual 'silent' drug excitation, the 'ghost in the addict'.

  11. Novel C-1 Substituted Cocaine Analogs Unlike Cocaine or Benztropine

    OpenAIRE

    Reith, Maarten E. A.; Ali, Solav; Hashim, Audrey; Sheikh, Imran S.; Theddu, Naresh; Gaddiraju, Narendra V.; Mehrotra, Suneet; Schmitt, Kyle C.; Murray, Thomas F.; Sershen, Henry; Unterwald, Ellen M.; Davis, Franklin A.

    2012-01-01

    Despite a wealth of information on cocaine-like compounds, there is no information on cocaine analogs with substitutions at C-1. Here, we report on (R)-(−)-cocaine analogs with various C-1 substituents: methyl (2), ethyl (3), n-propyl (4), n-pentyl (5), and phenyl (6). Analog 2 was equipotent to cocaine as an inhibitor of the dopamine transporter (DAT), whereas 3 and 6 were 3- and 10-fold more potent, respectively. None of the analogs, however, stimulated mouse locomotor activity, in contrast...

  12. Crack Cocaine-Induced Cardiac Conduction Abnormalities Are Reversed by Sodium Bicarbonate Infusion

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Miranda

    2013-01-01

    Full Text Available We report a dramatic case of a 19-year-old man with crack cocaine overdose with important clinical complications as cardiac arrest due to ventricular fibrillation and epileptics status. During this intoxication, electrocardiographic abnormalities similar to those found in tricyclic antidepressant poisoning were observed, and they were reversed by intravenous sodium bicarbonate infusion.

  13. Role of hypocretin/orexin receptor blockade on drug-taking and ultrasonic vocalizations (USVs) associated with low-effort self-administration of cathinone-derived 3,4-methylenedioxypyrovalerone (MDPV) in rats.

    Science.gov (United States)

    Simmons, Steven J; Martorana, Rose; Philogene-Khalid, Helene; Tran, Fionya H; Gentile, Taylor A; Xu, Xinyan; Su, Shu; Rawls, Scott M; Muschamp, John W

    2017-08-07

    Synthetic psychostimulant abuse, including cathinone-derived 3,4-methylenedioxypyrovalerone (MDPV), continues to increase in many countries. Similar to cocaine but with greater potency, MDPV elicits a transient sympathomimetic response by blocking cellular uptake of dopamine (DA) and norepinephrine (NE)-administration in some users is reported as euphoria-inducing much like cocaine and amphetamine. Pharmacological agents that disrupt excitatory transmission onto midbrain DA-producing neurons, including hypothalamic hypocretin/orexin (hcrt/ox) receptor antagonists, present attractive targets to aide abstinence maintenance by reducing psychostimulant-associated reward and reinforcement. The present study sought to assess the degree to which suvorexant, a dual hcrt/ox receptor antagonist, influences drug-taking as well as ultrasonic vocalizations (USVs) associated with MDPV self-administration. Rats were trained to self-administer MDPV (~0.03 mg/kg/inf, 3-s) for 14 days under a fixed-ratio 1 schedule of reinforcement, and effects of suvorexant (0, 3, 10, 30 mg/kg, i.p.) on drug-taking was assessed. USVs were recorded during a 30-min pre-lever period as well as during 2-h of MDPV self-administration. We observed that suvorexant modestly suppressed the number of MDPV infusions earned. Notably, we observed that suvorexant reduced 50-kHz USVs associated with pre- and post-lever time-points but did not noticeably alter call type profiles. Upon comparison of the two measures, we observed trending positive associations between suvorexant-induced changes in drug-taking and 50-kHz USVs. Results from this exploratory study provide support for the following: (1) studying how suvorexant may provide benefit to humans with stimulant use disorders, (2) identifying a potential role for orexin transmission in cathinone abuse, and (3) further interrogating the potential utility of rat USVs to predict drug consumption in preclinical models of substance use disorders.

  14. Pneumorachis after cocaine sniffing

    Directory of Open Access Journals (Sweden)

    S. Challita

    2014-01-01

    Full Text Available Air in the epidural space is called pneumorachis. The usual mechanism of pneumorachis is air diffusion from the mediastinal tissue layers through the inter-vertebral foramen. Alternatively, air can diffuse directly after spine traumas (e.g., blunt deceleration with vertebral dislocation or medical procedures. Several mechanisms could explain pneumomediastinum and pneumorachis after cocaine sniffing. Passive apnea and/or cough that occur after sniffing can cause intra alveolar hyper-pressure, which is responsible for alveolar rupture and air diffusion. Another mechanism is alveolar wall fragility and rupture induced by repeated cocaine sniffing, in turn causing air diffusion to the mediastinum, sub-cutaneous tissues and the epidural space. The diagnosis is usually made on Chest tomography scan. Management consists in close monitoring in the intensive care unit to detect aggravation of pneumomediastinum and pneumorachis, which would require surgical management. Supplemental nasal oxygen can be given to accelerate nitrogen washout. We present a case of a 28 years old male who presented to the emergency department for chest pain directly after sniffing cocaine. A computed tomography scan of the chest showed pneumomediastinum, pneumorachis and sub-cutaneous emphysema. The patient was admitted for 24 h: after that delay, surveillance chest tomodensitometry showed stability, and he could be discharged without further treatment.

  15. Addiction-Related Effects of DOV 216,303 and Cocaine

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Husum, Henriette; Brennum, Lise T

    2014-01-01

    DOV 216,303, an inhibitor of serotonin, noradrenaline and dopamine reuptake, belongs to a new line of drugs called 'triple reuptake inhibitors' that have been proposed for treatment of depression. The addictive drug cocaine has similar mechanism of action and exerts rewarding effects by blocking...... reuptake of dopamine, leading to increased extracellular concentrations of dopamine in the nucleus accumbens. Thus, DOV 216,303 and other triple reuptake inhibitors might be speculated to exhibit abuse potential, limiting their future therapeutic use. To further elucidate potential addictive properties...... of DOV 216,303, we conducted a comparative study of addiction-related effects of DOV 216,303 and cocaine in mice using acute self-administration, conditioned place preference (CPP) and drug-induced hyperlocomotion. Effects on accumbal extracellular dopamine levels were determined using microdialysis...

  16. Effects of continuous nicotine treatment and subsequent termination on cocaine versus food choice in male rhesus monkeys.

    Science.gov (United States)

    Schwienteck, Kathryn L; Negus, S Stevens; Poklis, Justin L; Banks, Matthew L

    2015-10-01

    One complicating factor in cocaine addiction may be concurrent exposure and potential dependence on nicotine. The aim of the present study was to determine the effects of continuous nicotine treatment and subsequent termination on cocaine versus food choice in rhesus monkeys (Macaca mulatta). For comparison, we also determined effects of the nicotinic receptor antagonist mecamylamine on cocaine versus food choice during continuous saline and nicotine treatment. Rhesus monkeys (N = 3) responded under a concurrent schedule of food pellet (1 g) and intravenous cocaine (0-0.1 mg/kg/injection) availability. Saline and ascending nicotine doses (0.1-1.0 mg/kg/hr, intravenous) were continuously infused for 7-day treatment periods and separated by 24-hr saline treatment periods. Acute effects of mecamylamine (0.32-1.8 mg/kg, intramuscular, 15 min pretreatment) were determined during continuous saline and 0.32-mg/kg/hr nicotine treatments. During saline treatment, cocaine maintained a dose-dependent increase in cocaine choice. Nicotine treatment did not alter cocaine versus food choice. In contrast, preference of 0.032 mg/kg/injection cocaine was attenuated 24 hr following termination of 0.32-mg/kg/hr nicotine treatment, despite no somatic abstinence signs being observed. Acute mecamylamine enhanced cocaine choice during saline treatment and mainly suppressed rates of behavior during nicotine treatment. Overall, continuous nicotine exposure, up to 1 mg/kg/hr, does not enhance cocaine choice and does not produce nicotine dependence, as demonstrated by the lack of abstinence signs. (c) 2015 APA, all rights reserved).

  17. Loss of Plasticity in the D2-Accumbens Pallidal Pathway Promotes Cocaine Seeking.

    Science.gov (United States)

    Heinsbroek, Jasper A; Neuhofer, Daniela N; Griffin, William C; Siegel, Griffin S; Bobadilla, Ana-Clara; Kupchik, Yonatan M; Kalivas, Peter W

    2017-01-25

    Distinct populations of D1- and D2-dopamine receptor-expressing medium spiny neurons (D1-/D2-MSNs) comprise the nucleus accumbens, and activity in D1-MSNs promotes, whereas activity in D2-MSNs inhibits, motivated behaviors. We used chemogenetics to extend D1-/D2-MSN cell specific regulation to cue-reinstated cocaine seeking in a mouse model of self-administration and relapse, and found that either increasing activity in D1-MSNs or decreasing activity in D2-MSNs augmented cue-induced reinstatement. Both D1- and D2-MSNs provide substantial GABAergic innervation to the ventral pallidum, and chemogenetic inhibition of ventral pallidal neurons blocked the augmented reinstatement elicited by chemogenetic regulation of either D1- or D2-MSNs. Because D1- and D2-MSNs innervate overlapping populations of ventral pallidal neurons, we next used optogenetics to examine whether changes in synaptic plasticity in D1- versus D2-MSN GABAergic synapses in the ventral pallidum could explain the differential regulation of VP activity. In mice trained to self-administer cocaine, GABAergic LTD was abolished in D2-, but not in D1-MSN synapses. A μ opioid receptor antagonist restored GABA currents in D2-, but not D1-MSN synapses of cocaine-trained mice, indicating that increased enkephalin tone on presynaptic μ opioid receptors was responsible for occluding the LTD. These results identify a behavioral function for D1-MSN innervation of the ventral pallidum, and suggest that losing LTDGABA in D2-MSN, but not D1-MSN input to ventral pallidum may promote cue-induced reinstatement of cocaine-seeking. More than 90% of ventral striatum is composed of two cell types, those expressing dopamine D1 or D2 receptors, which exert opposing roles on motivated behavior. Both cell types send GABAergic projections to the ventral pallidum and were found to differentially promote cue-induced reinstatement of cocaine seeking via the ventral pallidum. Furthermore, after cocaine self-administration, synaptic

  18. A randomized trial of hospital vs home self administration of vaginal misoprostol for medical abortion.

    Science.gov (United States)

    Shrestha, A; Sedhai, L B

    2014-01-01

    A combination of mifepristone followed after 24 hrs by misoprostol has proved a safe and effective abortifacient for termination of early pregnancy. Home use of misoprostol for medical abortion is still controversial in many countries including ours where women's literacy rate is low. Particularly in developing countries, this method markedly decreased the hospital visit which would be beneficial to patients and hospital staff. To see whether the home self administration of vaginal misoprostol was equally effective as administered by trained staff in terms of successful termination of early pregnancy. Secondary outcomes were bleeding and pain duration during medical abortion, side effects, reason for termination of pregnancy and women's acceptability of the procedure. One hundred and eighty eight women requesting medical abortion with pregnancy less than 63 days gestation were randomized into two groups either self administration of vaginal misoprostol (800 mcg) at home or hospital administration 24 hours after oral 200 mg mifepristone. Ultrasound was performed after 14 days to confirm complete abortion. The overall success rate was similar in two groups: 89.13% on home group Vs 86.9% in hospital group. Eleven out of 18 women (61.1%) having incomplete abortion had successful termination after 2nd dose misoprostol( 400 mcg). None of the women had continued pregnancy. Multigravida had slightly higher risk of failure (R.R: 1.04). Home self administration of vaginal misoprostol was safe and effective for early termination of medical abortion and was acceptable. Use of extra dose of misoprostol has advantage of higher completion rate of abortion.

  19. Behavioral economics of drug self-administration and drug abuse policy.

    Science.gov (United States)

    Hursh, S R

    1991-09-01

    The concepts of behavioral economics have proven useful for understanding the environmental control of overall levels of responding for a variety of commodities, including reinforcement by drug self-administration. These general concepts are summarized for application to the analysis of drug-reinforced behavior and proposed as the basis for future applications. This behavioral agenda includes the assessment of abuse liability, the assay of drug-reinforcer interactions, the design of drug abuse interventions, and the formulation of drug abuse public policy. These separate domains of investigation are described as part of an overall strategy for designing model projects to control drug use and testing public policy initiatives.

  20. Serotonin-3 Receptors in the Posterior Ventral Tegmental Area Regulate Ethanol Self-Administration of Alcohol-Preferring (P) Rats

    Science.gov (United States)

    Rodd, Zachary A.; Bell, Richard L.; Oster, Scott M.; Toalston, Jamie E.; Pommer, Tylene J.; McBride, William J.; Murphy, James M.

    2015-01-01

    Several studies indicated the involvement of serotonin-3 (5-HT3) receptors in regulating alcohol-drinking behavior. The objective of this study was to determine the involvement of 5-HT3 receptors within the ventral tegmental area (VTA) in regulating ethanol self-administration by alcohol-preferring (P) rats. Standard two-lever operant chambers were used to examine the effects of 7 consecutive bilateral micro-infusions of ICS205-930 (ICS), a 5-HT3 receptor antagonist, directly into the posterior VTA on the acquisition and maintenance of 15% (v/v) ethanol self-administration. P rats readily acquired ethanol self-administration by the 4th session. The three highest doses (0.125, 0.25 and 1.25 ug) of ICS prevented acquisition of ethanol self-administration. During the acquisition post-injection period, all rats treated with ICS demonstrated higher responding on the ethanol lever, with the highest dose producing the greatest effect. In contrast, during the maintenance phase, the 3 highest doses (0.75, 1.0 and 1.25 ug) of ICS significantly increased responding on the ethanol lever; following the 7-day dosing regimen, responding on the ethanol lever returned to control levels. Micro-infusion of ICS into the posterior VTA did not alter the low responding on the water lever, and did not alter saccharin (0.0125% w/v) self-administration.. Micro-infusion of ICS into the anterior VTA did not alter ethanol self-administration. Overall, the results of this study suggest that 5-HT3 receptors in the posterior VTA of the P rat may be involved in regulating ethanol self-administration. In addition, chronic operant ethanol self-administration, and/or repeated treatments with a 5-HT3 receptor antagonist may alter neuronal circuitry within the posterior VTA. PMID:20682192

  1. Evidence for habitual and goal-directed behavior following devaluation of cocaine: a multifaceted interpretation of relapse.

    Directory of Open Access Journals (Sweden)

    David H Root

    Full Text Available BACKGROUND: Cocaine addiction is characterized as a chronically relapsing disorder. It is believed that cues present during self-administration become learned and increase the probability that relapse will occur when they are confronted during abstinence. However, the way in which relapse-inducing cues are interpreted by the user has remained elusive. Recent theories of addiction posit that relapse-inducing cues cause relapse habitually or automatically, bypassing processing information related to the consequences of relapse. Alternatively, other theories hypothesize that relapse-inducing cues produce an expectation of the drug's consequences, designated as goal-directed relapse. Discrete discriminative stimuli signaling the availability of cocaine produce robust cue-induced responding after thirty days of abstinence. However, it is not known whether cue-induced responding is a goal-directed action or habit. METHODOLOGY/PRINCIPAL FINDINGS: We tested whether cue-induced responding is a goal-directed action or habit by explicitly pairing or unpairing cocaine with LiCl-induced sickness (n = 7/group, thereby decreasing or not altering the value of cocaine, respectively. Following thirty days of abstinence, no difference in responding between groups was found when animals were reintroduced to the self-administration environment alone, indicating habitual behavior. However, upon discriminative stimulus presentations, cocaine-sickness paired animals exhibited decreased cue-induced responding relative to unpaired controls, indicating goal-directed behavior. In spite of the difference between groups revealed during abstinent testing, no differences were found between groups when animals were under the influence of cocaine. CONCLUSIONS/SIGNIFICANCE: Unexpectedly, both habitual and goal-directed responding occurred during abstinent testing. Furthermore, habitual or goal-directed responding may have been induced by cues that differed in their correlation

  2. D-cycloserine combined with cue exposure therapy fails to attenuate subjective and physiological craving in cocaine dependence.

    Science.gov (United States)

    Santa Ana, Elizabeth J; Prisciandaro, James J; Saladin, Michael E; McRae-Clark, Aimee L; Shaftman, Stephanie R; Nietert, Paul J; Brady, Kathleen T

    2015-04-01

    Based on preclinical studies showing that the partial N-methyl-D-aspartate (NMDA) agonist D-cycloserine (DCS) facilitates extinction of cocaine self-administration and cocaine-induced conditioned place preference, we evaluated whether 50 mg of DCS would reduce craving to cocaine cues when combined with cue exposure (CE) in cocaine dependent humans. In this double-blind placebo-controlled pilot study, 47 cocaine dependent participants were randomized to DCS or placebo (PBO), plus CE. Participants received DCS or PBO 30 minutes prior to two CE sessions, conducted one day apart. Craving and heart rate was assessed prior to CE sessions, during CE trials, and after CE trials. These measures were assessed again at a 1-week follow-up (session 3) after the second CE session. DCS failed to significantly attenuate cocaine cue reactivity based on subjective craving and physiological reactivity (heart rate) compared to PBO. The CE protocol, consisting of repeated exposure to drug cues combined with skills training, resulted in extinction to cocaine cues as suggested by decreased craving within and between sessions in both treatment conditions. All participants exhibited elevated heart rate with repeated exposures, demonstrating a potentiation in heart rate between sessions. 50 mg of DCS may not be effective for extinguishing reactivity to drug cues for individuals with cocaine dependence. Future studies examining the effect of DCS on facilitating extinction to drug cues should examine variations in cue exposure length, number of CE presentations, and timing of DCS dose administration prior to cue exposures, which may differentially impact drug cue reactivity. © American Academy of Addiction Psychiatry.

  3. Addiction-related effects of DOV 216,303 and cocaine: A comparative study in the mouse.

    Science.gov (United States)

    Sørensen, Gunnar; Husum, Henriette; Brennum, Lise T; Bundgaard, Christoffer; Montezinho, Liliana C P; Mørk, Arne; Wörtwein, Gitta; Woldbye, David P D

    2014-06-01

    DOV 216,303, an inhibitor of serotonin, noradrenaline and dopamine reuptake, belongs to a new line of drugs called 'triple reuptake inhibitors' that have been proposed for treatment of depression. The addictive drug cocaine has similar mechanism of action and exerts rewarding effects by blocking reuptake of dopamine, leading to increased extracellular concentrations of dopamine in the nucleus accumbens. Thus, DOV 216,303 and other triple reuptake inhibitors might be speculated to exhibit abuse potential, limiting their future therapeutic use. To further elucidate potential addictive properties of DOV 216,303, we conducted a comparative study of addiction-related effects of DOV 216,303 and cocaine in mice using acute self-administration, conditioned place preference (CPP) and drug-induced hyperlocomotion. Effects on accumbal extracellular dopamine levels were determined using microdialysis, and we measured monoamine receptor occupancy as well as brain and plasma exposure. DOV 216,303 was self-administered acutely in the same dose range as cocaine. However, in the CPP model, DOV 216,303 did not induce place preference at doses where cocaine caused place preference. Higher doses of DOV 216,303 than cocaine were needed to induce hyperlocomotion and increase extracellular accumbal dopamine with effective doses being higher than effective doses used in depression models. Moreover, DOV 216,303 displayed a pharmacokinetic profile with lower potential for addiction than cocaine. Thus, high levels of DAT occupancy were reached slower and decayed more slowly after DOV 216,303 than cocaine administration. The present study shows that acute administration of DOV 216,303 displays some addictive-like properties in mice, but these were less pronounced than cocaine, most likely due to different pharmacokinetic profiles.

  4. Dopaminergic mechanisms of cocaine use

    NARCIS (Netherlands)

    Veeneman - Rijkens, M.M.J.

    2011-01-01

    Cocaine addiction is an enormous medical problem for which there is currently no effective pharmacotherapy. In order to develop treatments for this disorder, it is essential to understand the neurobiological underpinnings of cocaine addiction. One of the behavioral characteristics of addiction is an

  5. Effects of the neuropeptide S receptor antagonist RTI-118 on abuse-related facilitation of intracranial self-stimulation produced by cocaine and methylenedioxypyrovalerone (MDPV) in rats.

    Science.gov (United States)

    Bonano, Julie S; Runyon, Scott P; Hassler, Carla; Glennon, Richard A; Stevens Negus, S

    2014-11-15

    Neuropeptide S (NPS) is a neurotransmitter that activates the NPS receptor to modulate biological functions including anxiety-like behaviors, feeding, and drug reinforcement. RTI-118 is a novel NPS receptor antagonist that decreased cocaine self-administration in rats at doses that had little or no effect on food-maintained responding. To build on these previous findings, this study examined effects of RTI-118 on cocaine-induced facilitation of intracranial self-stimulation (ICSS) in rats. To provide a context for data interpretation, effects of RTI-118 were compared to effects of the kappa opioid receptor agonist U69,593, because the kappa opioid receptor is another peptide neurotransmitter receptor reported to modulate abuse-related cocaine effects. RTI-118 effects were also examined on ICSS facilitation produced by methylenedioxypyrovalerone (MDPV), a novel designer drug of abuse with some cocaine-like effects. Male Sprague-Dawley rats (n=12) with electrodes targeting the medial forebrain bundle responded under a fixed-ratio 1 schedule for range of brain stimulation frequencies. Under control conditions, brain stimulation maintained a frequency-dependent increase in ICSS rates. Cocaine (1.0-10mg/kg) and MDPV (3.2mg/kg) facilitated ICSS. RTI-118 (3.2-32mg/kg) alone produced little effect on ICSS but dose dependently blocked cocaine-induced ICSS facilitation. U69,593 (0.25-0.5mg/kg) also attenuated cocaine effects, but blockade of cocaine effects was incomplete even at a U69,593 dose that alone depressed ICSS. RTI-118 (32mg/kg) failed to block MDPV-induced ICSS facilitation. These results support further consideration of NPS receptor antagonists as candidate treatments for cocaine abuse and provide evidence for differential effects of a candidate treatment on abuse-related effects of cocaine and MDPV. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Enhanced self-administration of the CB1 receptor agonist WIN55,212-2 in olfactory bulbectomized rats: evaluation of possible serotonergic and dopaminergic underlying mechanisms

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    Petra eAmchova

    2014-03-01

    Full Text Available Depression has been associated with drug consumption, including heavy or problematic cannabis use. According to an animal model of depression and substance use disorder comorbidity, we combined the olfactory bulbectomy model of depression with intravenous drug self-administration procedure to verify whether depressive-like rats displayed higher voluntary intake of the CB1 receptor agonist WIN55,212-2 (WIN, 12.5 µg/kg/infusion. To this aim, olfactory-bulbectomized (OBX and sham-operated (SHAM Lister Hooded rats were allowed to self-administer WIN by lever-pressing under a continuous (FR-1 schedule of reinforcement in 2h daily sessions. Data showed that both OBX and SHAM rats developed stable WIN intake; yet, responses in OBX were constantly higher than in SHAM rats soon after the first week of training. In addition, OBX rats took significantly longer to extinguish the drug-seeking behaviour after vehicle substitution. Acute pre-treatment with serotonin 5HT1B receptor agonist, CGS-12066B (2.5-10 mg/kg, did not significantly modify WIN intake in OBX and SHAM Lister Hooded rats. Furthermore, acute pre-treatment with CGS-12066B (10 and 15 mg/kg did not alter responses in parallel groups of OBX and SHAM Sprague Dawley rats self-administering methamphetamine under higher (FR-2 reinforcement schedule with nose-poking as operandum. Finally, dopamine levels in the nucleus accumbens of OBX rats did not increase in response to a WIN challenge, as in SHAM rats, indicating a dopaminergic dysfunction in bulbectomized rats. Altogether, our findings suggest that a depressive state may alter cannabinoid CB1 receptor agonist-induced brain reward function and that a dopaminergic rather than a 5-HT1B mechanism is likely to underlie enhanced WIN self-administration in OBX rats.

  7. EtOH self-administration on shuttle box avoidance learning and extinction in rats.

    Science.gov (United States)

    Pallarés, M A; Nadal, R A; Hernández-Torres, M; Ferré, N A

    1997-01-01

    The effects of ethanol on the acquisition and extinction of the two-way active avoidance response were examined in adult, male Wistar rats from two treatment groups, oral self-administration of alcohol solution (10% v/v ethanol and 3% w/v glucose in distilled water) and oral self-administration of control solution (3% w/v glucose in distilled water). Alcohol or control solutions were available 1 h per day during 15 days simultaneously with food, with free water for the rest of the day. Blood was drawn in the last day of this phase to evaluate blood ethanol levels (BEL). After this period, rats were tested in a two-bottle paradigm for 1 h per day and placed in a shuttle box immediately afterwards. This phase went lasted for 10 days. Subjects were trained to avoid an electric foot shock in the first 5 days (15 trials per day). Following this, half of the subjects were tested in an "easy extinction with punishment" (EEP) and the other half in a "difficult extinction with punishment" (DEP) of the avoidance response for the last 5 days. Alcohol accelerates the avoidance responding acquisition, and no significant effects of alcohol were seen in the extinction phase. Data are discussed in terms of the specificity of the effects of alcohol on learning.

  8. Electrical stimulation of the lateral habenula produces an inhibitory effect on sucrose self-administration.

    Science.gov (United States)

    Friedman, Alexander; Lax, Elad; Dikshtein, Yahav; Abraham, Lital; Flaumenhaft, Yakov; Sudai, Einav; Ben-Tzion, Moshe; Yadid, Gal

    2011-01-01

    The lateral habenula (LHb) plays a role in prediction of negative reinforcement, punishment and aversive responses. In the current study, we examined the role that the LHb plays in regulation of negative reward responses and aversion. First, we tested the effect of intervention in LHb activity on sucrose reinforcing behavior. An electrode was implanted into the LHb and rats were trained to self-administer sucrose (20%; 16 days) until at least three days of stable performance were achieved (as represented by the number of active lever presses in self-administration cages). Rats subsequently received deep brain stimulation (DBS) of the LHb, which significantly reduced sucrose self-administration levels. In contrast, lesion of the LHb increased sucrose-seeking behavior, as demonstrated by a delayed extinction response to substitution of sucrose with water. Furthermore, in a modified non-rewarding conditioned-place-preference paradigm, DBS of the LHb led to aversion to the context associated with stimulation of this brain region. We postulate that electrical stimulation of the LHb attenuates positive reward-associated reinforcement by natural substances.

  9. Design and development of a modified runway model of mouse drug self-administration.

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    Pandy, Vijayapandi; Khan, Yasmin

    2016-02-23

    The present study established a novel mouse model of a runway drug self-administration in our laboratory. The operant runway apparatus consisted of three long runways arranged in a zig-zag manner. The methodology consisted of six distinct phases: habituation, preconditioning, conditioning, post-conditioning, extinction and reinstatement. The effects of saline were compared with escalating doses of either ethanol (0.5-4.0 g/kg, i.p), heroin (5-40 mg/kg, i.p), or nicotine (0.1-0.5mg/kg, i.p) administered in the goal box during the conditioning phase (day 1 to day 5). A significant decrease in the time of trained (conditioned) mice to reach the goal box confirmed the subjects' motivation to seek those drugs on day 6 (expression). The mice were then subjected to non-rewarded extinction trials for 5 days over which run times were significantly increased. After 5 days of abstinence, a priming dose of ethanol or heroin (1/5th of maximum dose used in conditioning) significantly reinstated the drug-seeking behavior. These results suggest that the modified runway model can serve as a powerful behavioral tool for the study of the behavioral and neurobiological bases of drug self-administration and, as such, is appropriate simple but powerful tool for investigating the drug-seeking behavior of laboratory mice.

  10. Pharmacokinetic correlates of the effects of a heroin vaccine on heroin self-administration in rats.

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    Michael D Raleigh

    Full Text Available The purpose of this study was to evaluate the effects of a morphine-conjugate vaccine (M-KLH on the acquisition, maintenance, and reinstatement of heroin self-administration (HSA in rats, and on heroin and metabolite distribution during heroin administration that approximated the self-administered dosing rate. Vaccination with M-KLH blocked heroin-primed reinstatement of heroin responding. Vaccination also decreased HSA at low heroin unit doses but produced a compensatory increase in heroin self-administration at high unit doses. Vaccination shifted the heroin dose-response curve to the right, indicating reduced heroin potency, and behavioral economic demand curve analysis further confirmed this effect. In a separate experiment heroin was administered at rates simulating heroin exposure during HSA. Heroin and its active metabolites, 6-acetylmorphine (6-AM and morphine, were retained in plasma and metabolite concentrations were reduced in brain in vaccinated rats compared to controls. Reductions in 6-AM concentrations in brain after vaccination were consistent with the changes in HSA rates accompanying vaccination. These data provide evidence that 6-AM is the principal mediator of heroin reinforcement, and the principal target of the M-KLH vaccine, in this model. While heroin vaccines may have potential as therapies for heroin addiction, high antibody to drug ratios appear to be important for obtaining maximal efficacy.

  11. Effects of 14-day treatment with the schedule III anorectic phendimetrazine on choice between cocaine and food in rhesus monkeys.

    Science.gov (United States)

    Banks, Matthew L; Blough, Bruce E; Negus, S Stevens

    2013-08-01

    The clinical utility of monoamine releasers such as phenmetrazine or d-amphetamine as candidate agonist medications for cocaine dependence is hindered by their high abuse liability. Phendimetrazine is a clinically available schedule III anorectic that functions as a prodrug for phenmetrazine and thus may have lower abuse liability. This study determined the effects of continuous 14-day treatment with phendimetrazine on cocaine vs. food choice in rhesus monkeys (N=4). Responding was maintained under a concurrent schedule of food delivery (1-g pellets, fixed-ratio 100 schedule) and cocaine injections (0-0.1mg/kg/injection, fixed-ratio 10 schedule). Cocaine choice dose-effect curves were determined daily before and during 14-day periods of continuous intravenous treatment with saline or (+)-phendimetrazine (0.32-1.0mg/kg/h). Effects of 14-day treatment with (+)-phenmetrazine (0.1-0.32 mg/kg/h; N=5) and d-amphetamine (0.032-0.1mg/kg/h; N=6) were also examined for comparison. During saline treatment, food was primarily chosen during availability of low cocaine doses (0, 0.0032, and 0.01 mg/kg/injection), and cocaine was primarily chosen during availability of higher cocaine doses (0.032 and 0.1mg/kg/injection). Phendimetrazine initially decreased overall responding without significantly altering cocaine choice. Over the course of 14 days, tolerance developed to rate decreasing effects, and phendimetrazine dose-dependently decreased cocaine choice (significant at 0.032 mg/kg/injection cocaine). Phenmetrazine and d-amphetamine produced qualitatively similar effects. These results demonstrate that phendimetrazine can produce significant, though modest, reductions in cocaine choice in rhesus monkeys. Phendimetrazine may be especially suitable as a candidate medication for human studies because of its schedule III clinical availability. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  12. COCAINE CARDIOMYOPATHY—A CASE REPORT

    OpenAIRE

    Georgiev Antonio; Zhivadinovik Julija

    2014-01-01

    Abstract: Cocaine is the second most common illicit drug used and the most frequent cause of drug related deaths. The use of cocaine is associated with both, acute and chronic complications, that may involve any system, but the most common system affected is cardiovascular one. Cocaine cardiomyopathy may result from the use of cocaine. This article presents a first case in Republic of Macedonia of 24-year-old male with reversible cocaine- related cardiomyopathy. Clinical presentation...

  13. ELECTROPHYSIOLOGICAL CHARACTERISTICS OF PARAVENTRICULAR THALAMIC (PVT NEURONS IN RESPONSE TO CHRONIC COCAINE EXPOSURE: EFFECTS OF COCAINE- AND AMPHETAMINE-REGULATED TRANSCRIPT (CART

    Directory of Open Access Journals (Sweden)

    Jiann Wei eYeoh

    2014-08-01

    Full Text Available Recent work has established that the paraventricular thalamus (PVT is a central node in the brain reward-seeking pathway. This role is likely mediated in part through the dense projections to the PVT from hypothalamic peptide transmitter systems such as orexin, and cocaine- and amphetamine-regulated transcript (CART, both of which play key roles in drug-seeking behaviour. Consistent with this proposition, we previously found that inactivation of the PVT or infusions of CART into the PVT suppressed drug-seeking behaviour in an animal model of contingent cocaine self-administration. Despite this work, very few studies have assessed the basic physiological properties of PVT neurons and how these parameters are altered by exposure to drugs such as cocaine. We set out to address these questions by employing an electrophysiological approach to record from anterior PVT (aPVT neurons from cocaine-treated and control animals. First, we determined the excitability of aPVT neurons by injecting a series of depolarizing current steps and characterizing the resulting action potential (AP discharge properties. Second, we investigated the effects of CART on excitatory synaptic inputs to aPVT neurons. We found that the majority of aPVT neurons exhibited tonic firing (TF, and initial bursting (IB consistent with previous studies. However, we also identified PVT neurons that exhibited delayed firing (DF, single spiking (SS and reluctant firing (RF. Interestingly, cocaine exposure shifted the proportion of aPVT neurons that exhibited TF. Further, application of CART suppressed excitatory synaptic drive to PVT. This finding is consistent with our previous behavioural data, which showed that CART signaling in the PVT negatively regulates drug-seeking behaviour. Together, these studies support previous anatomical evidence that the PVT can integrate reward-relevant information and provides a putative mechanism through which drugs of abuse can dysregulate this system in

  14. Lack of increased immediate early gene expression in rats reinstating cocaine-seeking behavior to discrete sensory cues.

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    Matthew D Riedy

    Full Text Available Drug-seeking behavior elicited by drug-associated cues contributes to relapse in addiction; however, whether relapse elicited by drug-associated conditioned reinforcers (CR versus discriminative stimuli (DS involves distinct or overlapping neuronal populations is unknown. To address this question, we developed a novel cocaine self-administration and cue-induced reinstatement paradigm that exposed the same rats to distinct cocaine-associated CR and DS. Rats were trained to self-administer cocaine in separate sessions. In one, a DS signaled cocaine availability; in the other, cocaine delivery was paired with a different CR. After extinction training and reinstatement testing, where both cues were presented in separate sessions, rats were sacrificed and processed for cellular analysis of temporal activity by fluorescent in situ hybridization (CatFISH for activity regulated cytoskeleton-associated protein (Arc mRNA and for radioactive in situ hybridization for Arc and zif268 mRNAs. CatFISH did not reveal significant changes in Arc mRNA expression. Similar results were obtained with radioactive in situ hybridization. We have shown that while rats reinstate drug seeking in response to temporally discrete presentations of distinct drug-associated cues, such reinstatement is not associated with increased transcriptional activation of Arc or zif268 mRNAs, suggesting that expression of these genes may not be necessary for cue-induced reinstatement of drug-seeking behavior.

  15. Cocaine tolerance in honey bees.

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    Eirik Søvik

    Full Text Available Increasingly invertebrates are being used to investigate the molecular and cellular effects of drugs of abuse to explore basic mechanisms of addiction. However, in mammals the principle factors contributing to addiction are long-term adaptive responses to repeated drug use. Here we examined whether adaptive responses to cocaine are also seen in invertebrates using the honey bee model system. Repeated topical treatment with a low dose of cocaine rendered bees resistant to the deleterious motor effects of a higher cocaine dose, indicating the development of physiological tolerance to cocaine in bees. Cocaine inhibits biogenic amine reuptake transporters, but neither acute nor repeated cocaine treatments caused measurable changes in levels of biogenic amines measured in whole bee brains. Our data show clear short and long-term behavioural responses of bees to cocaine administration, but caution that, despite the small size of the bee brain, measures of biogenic amines conducted at the whole-brain level may not reveal neurochemical effects of the drug.

  16. Peripheral intravenous line (image)

    Science.gov (United States)

    A peripheral intravenous line is a small, short plastic catheter that is placed through the skin into a vein, ... or foot, but occasionally in the head. A peripheral intravenous line is used to give fluids and ...

  17. Dopamine D3 and D2 receptor mechanisms in the abuse-related behavioral effects of cocaine: studies with preferential antagonists in squirrel monkeys.

    Science.gov (United States)

    Achat-Mendes, Cindy; Grundt, Peter; Cao, Jianjing; Platt, Donna M; Newman, Amy Hauck; Spealman, Roger D

    2010-08-01

    Dopamine (DA) D3 and D2 receptor mechanisms are implicated in cocaine's abuse-related behavioral effects, but the relative contribution of the two receptor subtypes is only partially characterized. This study investigated the role of D3 and D2 subtype mechanisms by determining the degree to which the D3-preferring antagonist PG01037 [N-{4-[4-(2,3-dichlorophenyl)-piperazin- 1-yl]-trans-but-2-enyl}-4-pyridine-2-yl-benzamide HCl] and the D2-preferring antagonist L-741626 [3-[4-(4-chlorophenyl)-4- hydroxypiperidin-1-yl]methyl-1H-indole] attenuated several behavioral effects of cocaine in squirrel monkeys. Quantitative observational studies established doses of each antagonist that did not produce untoward effects, which were used in subsequent comparisons. In addition, the ability of the D3-preferring agonist PD128907 [(R-(+)-trans-3,4a,10b-tetrahydro-4-propyl-2H,5H-[1]benzopyrano[4,3-b]-1,4-oxazin-9-ol)] and the D2-preferring agonist sumanirole [(R)-5,6-dihydro-5-(methylamino)-4H- imidazo[4,5,1-ij]quinolin-2(1H)-one(Z)-2-butenedioate] to reproduce cocaine's discriminative stimulus (DS) and priming effects were compared. In monkeys trained to discriminate cocaine from vehicle, both DA antagonists attenuated and both DA agonists partially reproduced cocaine's DS effects. PG01037 also selectively attenuated the cocaine-like DS effects of PD128907, whereas L-741626 attenuated the cocaine-like DS effects of both agonists. In self-administration studies, L-741626 nonselectively reduced cocaine- and food-maintained responding, whereas PG01037 was ineffective against either reinforcer. In studies involving reinstatement of extinguished cocaine seeking, both antagonists attenuated cocaine-induced reinstatement of responding, and both agonists induced at least partial reinstatement of cocaine seeking. L-741626 also attenuated sumanirole-induced, but not PD128907-induced, reinstatement of responding, whereas PG01037 was ineffective against either DA agonist. The results are

  18. Cocaine depresses GABAA current of hippocampal neurons.

    Science.gov (United States)

    Ye, J H; Liu, P L; Wu, W H; McArdle, J J

    1997-10-01

    Although blockade of dopamine re-uptake and the resulting elevation of excitatory agonists is commonly thought the primary mechanism of cocaine-induced seizures, it is possible that other neurotransmitters such as gamma-aminobutyric acid (GABA) are involved. To examine this possibility, the effects of cocaine on the whole cell GABA current (IGABA) of freshly isolated rat hippocampal neurons were investigated with the patch-clamp technique. Preincubation or acute application of cocaine reversibly suppressed IGABA. The IC50 was 127 microM when cocaine was applied before the application of GABA. The concentration-response relations of cocaine in various GABA concentrations revealed that cocaine inhibited IGABA non-competitively. This effect of cocaine appeared to be independent of voltage. The present study suggests that the GABA receptor/channel complex is also a target for cocaine's action. The suppression of IGABA may contribute to cocaine-induced seizures.

  19. Enhanced alcohol self-administration and reinstatement in a highly impulsive, inattentive recombinant inbred mouse strain

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    Maarten eLoos

    2013-10-01

    Full Text Available Deficits in executive control have frequently been associated with alcohol use disorder. Here we investigated to what extent pre-existing genetically encoded levels of impulsive/inattentive behavior associate with motivation to take alcohol and vulnerability to cue-induced reinstatement of alcohol seeking in an operant self-administration paradigm. We took advantage of BXD16, a recombinant inbred strain previously shown to have enhanced impulsivity and poor attentional control. We compared BXD16 with C57BL/6J mice in a simple choice reaction time task (SCRTT and confirmed its impulsive/inattentive phenotype. BXD16 mice were less active in a novel open field, and were equally active in an automated home cage environment, showing that increased impulsive responding of BXD16 mice could not be explained by enhanced general activity compared to C57BL/6J mice. After training in a sucrose/alcohol fading self-administration procedure, BXD16 showed increased motivation to earn 10% alcohol solution, both under fixed ratio (FR1 and progressive ratio (PR2 schedules of reinforcement. Responding on the active lever readily decreased during extinction training with no apparent differences between strains. However, upon re-exposure to alcohol-associated cues, alcohol seeking was reinstated to a larger extent in BXD16 than in C57BL/6J mice. Although further studies are needed to determine whether impulsivity/inattention and alcohol seeking depend on common or separate genetic loci, these data show that in mice enhanced impulsivity coincides with increased motivation to take alcohol, as well as relapse vulnerability.

  20. Oral self-administration of buprenorphine in the diet for analgesia in mice.

    Science.gov (United States)

    Molina-Cimadevila, M J; Segura, S; Merino, C; Ruiz-Reig, N; Andrés, B; de Madaria, E

    2014-07-01

    Postsurgical oral self-administration of analgesics in rodents is an interesting technique of providing analgesia, avoiding the negative effects of manipulation. Several strategies, using gelatin or nutella, have already been described. However, rodents require some habituation period to reach a good intake because of their neophobic behavior. The current study aimed to explore whether buprenorphine when mixed with an extruded diet offers a potential treatment option in the pain management of mice using a triple approach: by measuring the spontaneous intake in healthy animals; by using the hot-plate test; and finally by assessing the drug's ability to provide postoperative analgesia in a surgical intervention of moderate severity (intra-utero electroporation). Mice consumed during 20 hours, similar amounts of extruded diet alone, mixed with glucosaline, and mixed with buprenorphine (0.03 mg per pellet) or meloxicam (0.25 mg per pellet) both of which were diluted in glucosaline, showing that no neophobia was associated with these administrations. Relative increase from baseline latency (% maximal possible effect) in the hot-plate test at 20 h of administration was significantly higher for oral buprenorphine in diet 0.03 mg/pellet, and diet 0.15 mg/pellet, compared with placebo and no differences were found between those oral administrations and subcutaneous buprenorphine 0.1 mg/kg measured 3 h later. The treatment was also effective in attenuating the reductions in food consumption and body weight that occur after surgery. These data suggest that providing buprenorphine with the diet is a feasible and effective way of self-administration of analgesia in mice and does not cause neophobia and may easily contribute to the refinement of surgical procedures.

  1. Social facilitation of d-amphetamine self-administration in rats.

    Science.gov (United States)

    Gipson, Cassandra D; Yates, Justin R; Beckmann, Joshua S; Marusich, Julie A; Zentall, Thomas R; Bardo, Michael T

    2011-12-01

    The link between social influence and drug abuse has long been established in humans. However, preclinical animal models of drug abuse have only recently begun to consider the role of social influence. Since social factors influence the initiation and maintenance of drug use in humans, it is important to include these factors in preclinical animal models. The current study examined the effects of the presence of a social partner on responding for sucrose pellets under various motivational conditions, as well as on d-amphetamine (AMPH) self-administration. Rats were trained to lever press for either sucrose or AMPH (0.01 or 0.1 mg/kg/infusion unit dose). Following response stability, a novel same-sex conspecific was presented in an adjacent compartment separated by a clear divider, and responding for sucrose or AMPH reward was measured. Rats were allowed to restabilize, and subsequently given an additional partner presentation. Presence of the social partner increased responding only during the first pairing with the AMPH 0.1 mg/kg/infusion unit dose, whereas inhibition of responding was observed during the first pairing during access to the 0.01 mg/kg/infusion unit dose. Under free feed conditions, inhibition of sucrose pellet responding was observed in the presence of the social partner, but this effect was attenuated under food restriction. In contrast, the results demonstrate social facilitation of AMPH self-administration at a high unit dose, thus extending the influence of social factors to an operant conditioning task. This model of social facilitation may have important implications as a preclinical model of social influence on drug abuse.

  2. Brain-derived neurotrophic factor mediates the suppression of alcohol self-administration by memantine.

    Science.gov (United States)

    Jeanblanc, Jérôme; Coune, Fabien; Botia, Béatrice; Naassila, Mickaël

    2014-09-01

    Brain-derived neurotrophic factor (BDNF) within the striatum is part of a homeostatic pathway regulating alcohol consumption. Memantine, a non-competitive antagonist of N-methyl-D-aspartate receptors, induces expression of BDNF in several brain regions including the striatum. We hypothesized that memantine could decrease ethanol (EtOH) consumption via activation of the BNDF signalling pathway. Effects of memantine were evaluated in Long-Evans rats self-administering moderate or high amounts of EtOH 6, 30 and 54 hours after an acute injection (12.5 and 25 mg/kg). Motivation to consume alcohol was investigated through a progressive ratio paradigm. The possible role for BDNF in the memantine effect was tested by blockade of the TrkB receptor using the pharmacological agent K252a and by the BDNF scavenger TrkB-Fc. Candidate genes expression was also assessed by polymerase chain reaction array 4 and 28 hours after memantine injection. We found that memantine decreased EtOH self-administration and motivation to consume EtOH 6 and 30 hours post-injection. In addition, we found that inhibition or blockade of the BDNF signalling pathway prevented the early, but not the delayed decrease in EtOH consumption induced by memantine. Finally, Bdnf expression was differentially regulated between the early and delayed timepoints. These results demonstrate that an acute injection of memantine specifically reduces EtOH self-administration and motivation to consume EtOH for at least 30 hours. Moreover, we showed that BDNF was responsible for the early effect, but that the delayed effect was BDNF-independent.

  3. Genetic factors control nicotine self-administration in isogenic adolescent rat strains.

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    Hao Chen

    Full Text Available Adult cigarette smokers usually become dependent on cigarettes during adolescence. Despite recent advances in addiction genetics, little data delineates the genetic factors that account for the vulnerability of humans to smoke tobacco. We studied the operant nicotine self-administration (SA behavior of six inbred strains of adolescent male rats (Fisher 344, Brown Norway, Dark Agouti, Spontaneous Hypertensive Rat, Wistar Kyoto and Lewis and six selected F1 hybrids. All rats were trained to press a lever to obtain food starting on postnatal day (PN 32, and then nicotine (0.03 mg/kg/infusion, i.v. reinforcement was made available on PN41-42 (10 consecutive daily 2 h sessions. Of the 12 isogenic strains, Fisher rats self-administered the fewest nicotine infusions (1.45 ± 0.36/d during the last 3 d, while Lewis rats took the most nicotine (13.0 ± 1.4/d. These strains sorted into high, intermediate and low self-administration groups in 2, 2, and 8 strains, respectively. The influence of heredity on nicotine SA (0.64 is similar to that reported for humans. Therefore, this panel of isogenic rat strains effectively models the overall impact of genetics on the vulnerability to acquire nicotine-reinforced behavior during adolescence. Separate groups of rats responded for food starting on PN41. The correlation between nicotine and food reward was not significant. Hence, the genetic control of the motivation to obtain nicotine is distinctly different from food reward, indicating the specificity of the underlying genetic mechanisms. Lastly, the behavior of F1 hybrids was not predicted from the additive behavior of the parental strains, indicating the impact of significant gene-gene interactions on the susceptibility to nicotine reward. Taken together, the behavioral characteristics of this model indicate its strong potential to identify specific genes mediating the human vulnerability to smoke cigarettes.

  4. Androgens and opiates: testosterone interaction with morphine self-administration in male rats.

    Science.gov (United States)

    Cooper, Sarah E; Wood, Ruth I

    2014-05-07

    Abuse of anabolic androgenic steroids (AAS) and opioids intersects in athletics. Evidence from humans and animals suggests that AAS may act in the brain through opioidergic mechanisms, and may potentiate effects of opioids. To determine whether AAS enhance motivation for opioid intake, in this study, male rats were treated chronically for 6 weeks with high levels of testosterone (7.5 mg/kg) or vehicle subcutaneously, and they were tested for morphine self-administration under fixed-ratio (FR) and progressive-ratio (PR) schedules. Initially, rats received chronic morphine infusion (16.8-50 mg/kg/day) over 7 days. Subsequently, rats were tested for morphine self-administration (3.2 mg/kg) 6 h/day for 3 days under an FR1 schedule, and for 7 days under a PR 9-4 schedule. Under the FR1 schedule, controls self-administered more morphine (95.9±8.5 mg/kg) than testosterone-treated rats (63.2±7.2 mg/kg; P<0.05). Under the PR schedule, there was no effect of testosterone on morphine intake or operant responding (26.7±5.7 responses vs. 30.9±5.9 responses for vehicle; NS). To determine whether testosterone enhances morphine sedation, additional rats were treated with testosterone or vehicle and evaluated for locomotor behavior and rearing activity over 30 min in response to saline or 10 mg/kg morphine. Morphine inhibited locomotor activity and rearing; testosterone selectively reduced rearing behavior, but did not alter locomotor behavior. These results suggest that testosterone does not increase motivation for morphine.

  5. Adrenaline in anaphylaxis treatment and self-administration: experience from an inner city emergency department.

    Science.gov (United States)

    Mostmans, Y; Grosber, M; Blykers, M; Mols, P; Naeije, N; Gutermuth, J

    2017-03-01

    Anaphylaxis is a life-threatening emergency of which reliable epidemiological data are lacking. This study aimed to analyze how quickly patients presenting with anaphylaxis were treated in emergency and whether treatment followed the European Academy of Allergy and Clinical Immunology (EAACI) guidelines. Patient data were collected between April 2009 and April 2013. Emergency doctors completed a questionnaire for adult patients presenting at the emergency department (ED) of the St. Pierre hospital in Brussels with anaphylaxis. Inclusion criteria were based on the Sampson criteria of anaphylaxis. Data were analyzed using a Microsoft Excel database. About 0.04% (100/230878) of all emergency visits in adults presented with anaphylaxis. 64% of patients received their first medical help later than 30 min after symptom onset. 67% of patients received adrenaline, 85% oral antihistamines, and 89% received IV glucocorticosteroids. 46/100 patients were discharged directly from the ED, of which 87% received further medical prescriptions for self-administration: 67% corticosteroids, 83% antihistamines, and 9% intramuscular adrenaline. 74% were instructed to consult an allergologist for adequate diagnosis. 54/100 patients were hospitalized. The majority of patients were treated according to the EAACI guidelines for management of anaphylaxis, but only a minority received the recommended adrenaline auto-injector for self-administration at discharge. Because the majority of patients received medical help later than 30 min after symptom onset, adrenaline auto-injector prescription is a necessity. The low rate of doctors prescribing adrenaline auto-injectors in the ED setting underlines the need to train doctors of various backgrounds in prevention and treatment of anaphylaxis and the close collaboration with allergologists. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Naltrexone Maintenance Decreases Cannabis Self-Administration and Subjective Effects in Daily Cannabis Smokers.

    Science.gov (United States)

    Haney, Margaret; Ramesh, Divya; Glass, Andrew; Pavlicova, Martina; Bedi, Gillinder; Cooper, Ziva D

    2015-10-01

    Given that cannabis use is increasing in the United States, pharmacological treatment options to treat cannabis use disorder are needed. Opioid antagonists modulate cannabinoid effects and may offer a potential approach to reducing cannabis use. In this double-blind, placebo-controlled human laboratory study, we assessed the effects of naltrexone maintenance on the reinforcing, subjective, psychomotor, and cardiovascular effects of active and inactive cannabis. Nontreatment-seeking, daily cannabis smokers were randomized to receive naltrexone (50 mg: n=18 M and 5 F) or placebo (0 mg; n=26 M and 2 F) capsules for 16 days. Before, during, and after medication maintenance, participants completed 10 laboratory sessions over 4-6 weeks, assessing cannabis' behavioral and cardiovascular effects. Medication compliance was verified by observed capsule administration, plasma naltrexone, and urinary riboflavin. Relative to placebo, maintenance on naltrexone significantly reduced both active cannabis self-administration and its positive subjective effects ('good effect'). Participants in the placebo group had 7.6 times (95% CI: 1.1-51.8) the odds of self-administering active cannabis compared with the naltrexone group. This attenuation of reinforcing and positive subjective effects also influenced cannabis use in the natural ecology. Naltrexone had intrinsic effects: decreasing ratings of friendliness, food intake, and systolic blood pressure, and increasing spontaneous reports of stomach upset and headache, yet dropout rates were comparable between groups. In summary, we show for the first time that maintenance on naltrexone decreased cannabis self-administration and ratings of 'good effect' in nontreatment-seeking daily cannabis smokers. Clinical studies in patients motivated to reduce their cannabis use are warranted to evaluate naltrexone's efficacy as a treatment for cannabis use disorder.

  7. The Effects of Maternal Separation on Adult Methamphetamine Self-Administration, Extinction, Reinstatement, and MeCP2 Immunoreactivity in the Nucleus Accumbens

    Directory of Open Access Journals (Sweden)

    Candace R. Lewis

    2013-06-01

    Full Text Available The maternal separation (MS paradigm is an animal model of early life stress. Animals subjected to MS during the first two weeks of life display altered behavioral and neuroendocrinological stress responses as adults. MS also produces altered responsiveness to and self-administration (SA of various drugs of abuse including cocaine, ethanol, opioids, and amphetamine. Methamphetamine (METH causes great harm to both the individual user and to society; yet, no studies have examined the effects of MS on METH SA. This study was performed to examine the effects of MS on the acquisition of METH SA, extinction, and reinstatement of METH-seeking behavior in adulthood. Given the known influence of early life stress and drug exposure on epigenetic processes, group differences in levels of the epigenetic marker methyl CpG binding protein 2 (MeCP2 in the nucleus accumbens (NAc core were also investigated. Long-Evans pups and dams were separated on postnatal days (PND 2-14 for either 180 (MS180 or 15 min (MS15. Male offspring were allowed to acquire METH SA (0.05 mg/kg/infusion in 15 2-hr daily sessions starting at PND67, followed by extinction training and cue-induced reinstatement of METH-seeking behavior. Rats were then assessed for MeCP2 levels in the NAc core by immunohistochemistry. The MS180 group self-administered significantly more METH and acquired SA earlier than the MS15 group. No group differences in extinction or cue-induced reinstatement were observed. MS15 rats had significantly elevated MeCP2-immunoreactive cells in the NAc core as compared to MS180 rats. Together, these data suggest that MS has lasting influences on METH SA as well as epigenetic processes in the brain reward circuitry.

  8. Optogenetic stimulation of accumbens shell or shell projections to lateral hypothalamus produce differential effects on the motivation for cocaine.

    Science.gov (United States)

    Larson, Erin B; Wissman, Anne M; Loriaux, Amy L; Kourrich, Saïd; Self, David W

    2015-02-25

    Previous studies suggest that pharmacological or molecular activation of the nucleus accumbens shell (AcbSh) facilitates extinction of cocaine-seeking behavior. However, overexpression of CREB, which increases excitability of AcbSh neurons, enhances cocaine-seeking behavior while producing depression-like behavior in tests of mood. These discrepancies may reflect activity in differential AcbSh outputs, including those to the lateral hypothalamus (LH), a target region known to influence addictive behavior and mood. Presently, it is unknown whether there is a causal link between altered activity in the AcbSh-LH pathway and changes in the motivation for cocaine. In this study, we used an optogenetics approach to either globally stimulate AcbSh neurons or to selectively stimulate AcbSh terminal projections in the LH, in rats self-administering cocaine. We found that stimulation of the AcbSh-LH pathway enhanced the motivation to self-administer cocaine in progressive ratio testing, and led to long-lasting facilitation of cocaine-seeking behavior during extinction tests conducted after withdrawal from cocaine self-administration. In contrast, global AcbSh stimulation reduced extinction responding. We compared these opposing motivational effects with effects on mood using the forced swim test, where both global AcbSh neuron and selective AcbSh-LH terminal stimulation facilitated depression-like behavioral despair. Together, these findings suggest that the AcbSh neurons convey complex, pathway-specific modulation of addiction and depression-like behavior, and that these motivation and mood phenomenon are dissociable.

  9. Metabolomics of cocaine: implications in toxicity.

    Science.gov (United States)

    Dinis-Oliveira, Ricardo Jorge

    2015-01-01

    Cocaine is the most commonly used illicit drug among those seeking care in Emergency Departments or drug detoxification centers. Cocaine, chemically known as benzoylmethylecgonine, is a naturally occurring substance found in the leaves of the Erythroxylum coca plant. The pharmacokinetics of cocaine is dependent on multiple factors, such as physical/chemical form, route of administration, genetics and concurrent consumption of alcohol. This review aims to discuss metabolomics of cocaine, namely by presenting all known metabolites of cocaine and their roles in the cocaine-mediated toxic effects.

  10. Gabapentin potentiates sensitivity to the interoceptive effects of alcohol and increases alcohol self-administration in rats.

    Science.gov (United States)

    Besheer, Joyce; Frisbee, Suzanne; Randall, Patrick A; Jaramillo, Anel A; Masciello, Maria

    2016-02-01

    Gabapentin, a drug used in the treatment of epileptic seizures and neuropathic pain, has shown efficacy in the treatment of alcohol dependence. Moreover, given that gabapentin is used in the general population (e.g., non-dependent individuals, social drinkers), we sought to utilize preclinical assessments to examine the effects of gabapentin on sensitivity to moderate alcohol doses and alcohol self-administration in rats with a history of moderate drinking. To this end, we assessed whether gabapentin (0, 10, 30, 120 mg/kg, IG) pretreatment alters sensitivity to experimenter- and self-administered alcohol, and whether gabapentin alone has alcohol-like discriminative stimulus effects in rats trained to discriminate alcohol dose (1 g/kg, IG) vs. water. Second, we assessed whether gabapentin (0, 10, 30, 60 mg/kg, IG) would alter alcohol self-administration. Gabapentin pretreatment potentiated the interoceptive effects of both experimenter-administered and self-administered alcohol in discrimination-trained rats. Additionally, the highest gabapentin doses tested (30 and 120 mg/kg) were found to have partial alcohol-like discriminative stimulus effects when administered alone (e.g., without alcohol). In the self-administration trained rats, gabapentin pretreatment (60 mg/kg) resulted in an escalation in alcohol self-administration. Given the importance of interoceptive drug cues in priming and maintaining self-administration, these data define a specific behavioral mechanism (i.e., potentiation of alcohol effects) by which gabapentin may increase alcohol self-administration in non-dependent populations.

  11. Persistent cue-evoked activity of accumbens neurons after prolonged abstinence from self-administered cocaine.

    Science.gov (United States)

    Ghitza, Udi E; Fabbricatore, Anthony T; Prokopenko, Volodymyr; Pawlak, Anthony P; West, Mark O

    2003-08-13

    Persistent neural processing of information regarding drug-predictive environmental stimuli may be involved in motivating drug abusers to engage in drug seeking after abstinence. The addictive effects of various drugs depend on the mesocorticolimbic dopamine system innervating the nucleus accumbens. We used single-unit recording in rats to test whether accumbens neurons exhibit responses to a discriminative stimulus (SD) tone previously paired with cocaine availability during cocaine self-administration. Presentation of the tone after 3-4 weeks of abstinence resulted in a cue-induced relapse of drug seeking under extinction conditions. Accumbens neurons did not exhibit tone-evoked activity before cocaine self-administration training but exhibited significant SD tone-evoked activity during extinction. Under extinction conditions, shell neurons exhibited significantly greater activity evoked by the SD tone than that evoked by a neutral tone (i.e., never paired with reinforcement). In contrast, core neurons responded indiscriminately to presentations of the SD tone or the neutral tone. Accumbens shell neurons exhibited significantly greater SD tone-evoked activity than did accumbens core neurons. Although the onset of SD tone-evoked activity occurred well before the earliest movements commenced (150 msec), this activity often persisted beyond the onset of tone-evoked movements. These results indicate that accumbens shell neurons exhibit persistent processing of information regarding reward-related stimuli after prolonged drug abstinence. Moreover, the accumbens shell appears to be involved in discriminating the motivational value of reward-related associative stimuli, whereas the accumbens core does not.

  12. Methylenedioxypyrovalerone (MDPV mimics cocaine in its physiological and behavioral effects but induces distinct changes in NAc glucose

    Directory of Open Access Journals (Sweden)

    Ken Taro Wakabayashi

    2015-09-01

    Full Text Available Methylenedioxypyrovalerone (MDPV is generally considered to be a more potent cocaine-like psychostimulant, as it shares a similar pharmacological profile with cocaine and induces similar physiological and locomotor responses. Recently, we showed that intravenous cocaine induces rapid rise in nucleus accumbens (NAc glucose and established its relation to neural activation triggered by the peripheral drug actions. This study was conducted to find out whether MDPV, at a behaviorally equivalent dose, will share a similar pattern of NAc glucose dynamics. Using enzyme-based glucose sensors coupled with amperometery in freely moving rats, we found that MDPV tonically decreases NAc glucose levels, a response that is opposite to what we previously observed with cocaine. By analyzing Skin-Muscle temperature differentials, a valid measure of skin vascular tone, we found that MDPV induces vasoconstriction; a similar effect at the level of cerebral vessels could be responsible for the MDPV-induced decrease in NAc glucose. While cocaine also induced comparable, if not slightly stronger peripheral vasoconstriction, this effect was overpowered by local neural activity-induced vasodilation, resulting in rapid surge in NAc glucose. These results imply that cocaine-users may be more susceptible to addiction than MDPV-users due to the presence of an interoceptive signal (i.e. sensory cue, which may result in earlier and more direct reward detection. Additionally, while health complications arising from acute cocaine use are typically cardiovascular related, MDPV may be more dangerous to the brain due to uncompensated cerebral vasoconstriction.

  13. Methylenedioxypyrovalerone (MDPV) mimics cocaine in its physiological and behavioral effects but induces distinct changes in NAc glucose.

    Science.gov (United States)

    Wakabayashi, Ken T; Ren, Suelynn E; Kiyatkin, Eugene A

    2015-01-01

    Methylenedioxypyrovalerone (MDPV) is generally considered to be a more potent cocaine-like psychostimulant, as it shares a similar pharmacological profile with cocaine and induces similar physiological and locomotor responses. Recently, we showed that intravenous cocaine induces rapid rise in nucleus accumbens (NAc) glucose and established its relation to neural activation triggered by the peripheral drug actions. This study was conducted to find out whether MDPV, at a behaviorally equivalent dose, shares a similar pattern of NAc glucose dynamics. Using enzyme-based glucose sensors coupled with amperometery in freely moving rats, we found that MDPV tonically decreases NAc glucose levels, a response that is opposite to what we previously observed with cocaine. By analyzing Skin-Muscle temperature differentials, a valid measure of skin vascular tone, we found that MDPV induces vasoconstriction; a similar effect at the level of cerebral vessels could be responsible for the MDPV-induced decrease in NAc glucose. While cocaine also induced comparable, if not slightly stronger peripheral vasoconstriction, this effect was overpowered by local neural activity-induced vasodilation, resulting in rapid surge in NAc glucose. These results imply that cocaine-users may be more susceptible to addiction than MDPV-users due to the presence of an interoceptive signal (i.e., sensory cue), which may result in earlier and more direct reward detection. Additionally, while health complications arising from acute cocaine use are typically cardiovascular related, MDPV may be more dangerous to the brain due to uncompensated cerebral vasoconstriction.

  14. Cocaine and "pharmacological kindling" in the rat.

    Science.gov (United States)

    Stripling, J S

    1983-11-01

    The concept of "pharmacological kindling" has been used to explain the behavioral sensitization to cocaine produced by repeated administration of subconvulsive doses. This idea was tested by the repeated administration of cocaine to rats followed by electrical kindling of the olfactory bulb (a site at which cocaine has prominent electrophysiologic effects). No significant effect of cocaine on kindling was found. The relationship of this finding to studies using other drugs is discussed.

  15. Citalopram enhances cocaine's subjective effects in rats

    OpenAIRE

    Soto, Paul L.; Hiranita, Takato; Katz, Jonathan L.

    2009-01-01

    Serotonin-selective reuptake inhibitors (SSRIs) have been shown to enhance the locomotor stimulatory, discriminative-stimulus, and convulsive effects of cocaine in rodents. A pharmacokinetic mechanism for the interaction is supported by increases in the brain levels of cocaine by fluoxetine treatment. Furthermore, the locomotor-stimulant effects of cocaine in rodents are enhanced by fluoxetine and fluvoxamine, SSRIs known to inhibit cocaine-metabolizing cytochrome P450 enzymes, whereas citalo...

  16. Using growth models to relate acquisition of nicotine self-administration to break point and nicotinic receptor binding.

    Science.gov (United States)

    Donny, Eric C; Lanza, Stephanie T; Balster, Robert L; Collins, Linda M; Caggiula, Anthony; Rowell, Peter P

    2004-07-15

    Growth modeling can be used to characterize individual and mean acquisition trajectories for drug self-administration. Individual characteristics can also be incorporated into the growth model, providing a powerful tool for investigating the relationship between acquisition and other behavioral and biological measures. We illustrate the utility of this method by examining the relationship between acquisition of nicotine self-administration and (1) break point on a progressive ratio schedule of reinforcement, and (2) the density of brain nicotinic receptors (B(max)). Daily infusion rates from male and female Sprague-Dawley rats were modeled with break point or B(max) as time-invariant covariates. Use of this model led to two novel findings regarding individual differences in acquisition. First, greater rates of change in infusions early in acquisition were related to higher break points; this relationship was mediated by a similar effect of increasing the number of responses required to obtain nicotine. Second, animals displaying more resistance to increases in the response requirement during acquisition, as indicated by a smaller drop in the rate of nicotine self-administration, generally had fewer nicotinic receptors at the end of the experiment. The relationships revealed demonstrate the usefulness of growth models in the quantitative analysis of individual differences in drug self-administration behavior.

  17. Role of Corticotropin Releasing Factor 1 Signaling in Cocaine Seeking during Early Extinction in Female and Male Rats.

    Directory of Open Access Journals (Sweden)

    Angie M Cason

    Full Text Available Locus coeruleus norepinephrine (LC-NE and corticotropin releasing factor (CRF neurons are involved in stress responses, including stress's ability to drive drug relapse. Previous animal studies indicate that female rats exhibit greater drug seeking than male rats during initial drug abstinence. Moreover, females are more sensitive to the effect of stress to drive drug seeking than males. Finally, LC-NE neurons are more sensitive to CRF in females compared to males. We hypothesized that increased drug seeking in females on extinction day one (ED1 is due to increased response to the stress of early withdrawal and is dependent upon the increased response of LC in females to CRF. We predicted that LC-NE neurons would exhibit Fos activation on ED1, and that blocking CRF1 signaling would decrease drug seeking on ED1 measured by responding on an active lever previously associated with cocaine self- administration. After chronic cocaine self-administration, female and male rats underwent a test for initial extinction responding by measuring lever pressing in the absence of cocaine. Prior to this Extinction Day 1 (ED1 session, rats were injected with vehicle or the selective CRF1 antagonist (CP to measure effects of CRF antagonism on drug seeking during early abstinence. ED1 increased corticosterone in female rats, in proportion to lever responding in male and female, indicating that ED1 was stressful. Pretreatment with CP decreased cocaine seeking on ED1 more effectively in female compared to male rats. This increase in responding was associated with an increase in activation of LC NE neurons. Together, these findings indicate that stress, and signaling at CRF receptors in LC, may be involved in the increased drug seeking during initial abstinence.

  18. Reduced attentional scope in cocaine polydrug users

    NARCIS (Netherlands)

    Colzato, L.S.; van den Wildenberg, W.P.M.; Hommel, B.

    2009-01-01

    Cocaine is Europe's second preferred recreational drug after cannabis but very little is known about possible cognitive impairments in the upcoming type of recreational cocaine user (monthly consumption). We asked whether recreational use of cocaine impacts early attentional selection processes. Coc

  19. The emergency care of cocaine intoxications.

    NARCIS (Netherlands)

    Vroegop, M.P.; Franssen, E.J.; Voort, P.H. van der; Berg, T.N. van den; Langeweg, R.J.; Kramers, C.

    2009-01-01

    Cocaine is frequently used, especially among adolescents and by men between the age of 25 and 44. Many of them are able to use cocaine in normal day-to-day life, without any problems. Reduced prices of cocaine and other recreational drugs such as MDMA (ecstasy) and gamma hydroxybutyrate (GHB) has le

  20. Differential involvement of GABAA and GABAB receptors in propofol self-administration in rats

    Institute of Scientific and Technical Information of China (English)

    Bo YANG; Ben-fu WANG; Miao-jun LAI; Fu-qiang ZHANG; Xiao-wei YANG; Wen-hua ZHOU; Qing-quan LIAN

    2011-01-01

    Propofol has shown abuse potential.The aim of the present study is to investigate the effects of GABAA antagonist and GABAB agonist on propofol reinforcement.Methods:Sprague-Dawley rats were trained to self-administer propofol at a dose of 1.7 mg/kg per infusion under a fixed ratio (FR1) schedule of reinforcement for 14 d.In a separate set of experiments,food-maintained self-administration under a fixed ratio (FR5) schedule and locomotor activities of Sprague-Dawley rats were examined.Results:GABAA receptor antagonist bicuculline (0.25 mg/kg,ip) significantly increased the number of injections and active responses.Pretreatment with GABAB receptor agonist baclofen (3 mg/kg,ip) significantly decreased the number of active responses and total infusions of propofol during the training session.Moreover,microinjection of baclofen (50 and 100 ng/side) into the ventral tegmental area (VTA) significantly decreased the number of active responses and total infusions of propofol.Neither baclofen (1-3 mg/kg,ip) nor bicuculline (0.25-1 mg/kg,ip) affected food-maintained responses or motor activities.Conclusion:Propofol maintains its reward properties partially through GABAA receptor activation.Stimulation of GABA~ receptors in VTA may counteract the reinforcing properties of propofol.

  1. Plasma proteomic alterations in non-human primates and humans after chronic alcohol self-administration.

    Science.gov (United States)

    Freeman, Willard M; Vanguilder, Heather D; Guidone, Elizabeth; Krystal, John H; Grant, Kathleen A; Vrana, Kent E

    2011-08-01

    Objective diagnostics of excessive alcohol use are valuable tools in the identification and monitoring of subjects with alcohol use disorders. A number of potential biomarkers of alcohol intake have been proposed, but none have reached widespread clinical usage, often due to limited diagnostic sensitivity and specificity. In order to identify novel potential biomarkers, we performed proteomic biomarker target discovery in plasma samples from non-human primates that chronically self-administer high levels of ethanol. Two-dimensional difference in-gel electrophoresis (2D-DIGE) was used to quantify plasma proteins from within-subject samples collected before exposure to ethanol and after 3 months of excessive ethanol self-administration. Highly abundant plasma proteins were depleted from plasma samples to increase proteomic coverage. Altered plasma levels of serum amyloid A4 (SAA4), retinol-binding protein, inter-alpha inhibitor H4, clusterin, and fibronectin, identified by 2D-DIGE analysis, were confirmed in unmanipulated, whole plasma from these animals by immunoblotting. Examination of these target plasma proteins in human subjects with excessive alcohol consumption (and control subjects) revealed increased levels of SAA4 and clusterin and decreased levels of fibronectin compared to controls. These proteins not only serve as targets for further development as biomarker candidates or components of biomarker panels, but also add to the growing understanding of dysregulated immune function and lipoprotein metabolism with chronic, excessive alcohol consumption.

  2. Differential regulation of MeCP2 and PP1 in passive or voluntary administration of cocaine or food.

    Science.gov (United States)

    Bodetto, Sarah Pol; Romieu, Pascal; Sartori, Maxime; Tesone-Coelho, Carolina; Majchrzak, Monique; Barbelivien, Alexandra; Zwiller, Jean; Anglard, Patrick

    2014-12-01

    Cocaine exposure induces changes in the expression of numerous genes, in part through epigenetic modifications. We have initially shown that cocaine increases the expression of the chromatin remodeling protein methyl-CpG binding protein 2 (MeCP2) and characterized the protein phosphatase-1Cβ (PP1Cβ) gene, as repressed by passive i.p. cocaine injections through a Mecp2-mediated mechanism involving de novo DNA methylation. Both proteins being involved in learning and memory processes, we investigated whether voluntary cocaine administration would similarly affect their expression using an operant self-administration paradigm. Passive and voluntary i.v. cocaine intake was found to induce Mecp2 and to repress PP1Cβ in the prefrontal cortex and the caudate putamen. This observation is consistent with the role of Mecp2 acting as a transcriptional repressor of PP1Cβ and shows that passive intake was sufficient to alter their expression. Surprisingly, striking differences were observed under the same conditions in food-restricted rats tested for food pellet delivery. In the prefrontal cortex and throughout the striatum, both proteins were induced by food operant conditioning, but remained unaffected by passive food delivery. Although cocaine and food activate a common reward circuit, changes observed in the expression of other genes such as reelin and GAD67 provide new insights into molecular mechanisms differentiating neuroadaptations triggered by each reinforcer. The identification of hitherto unknown genes differentially regulated by drugs of abuse and a natural reinforcer should improve our understanding of how two rewarding stimuli differ in their ability to drive behavior.

  3. Suppression of activity-regulated cytoskeleton-associated gene expression in the dorsal striatum attenuates extinction of cocaine-seeking.

    Science.gov (United States)

    Hearing, Matthew C; Schwendt, Marek; McGinty, Jacqueline F

    2011-07-01

    The caudate putamen (CPu) has been implicated in habit learning and neuroadaptive changes that mediate the compulsive nature of drug-seeking following chronic cocaine self-administration. Re-exposure to an operant chamber previously associated with cocaine, but not yoked-saline, increases activity-regulated cytoskeleton-associated (Arc) gene mRNA expression within the dorsolateral (dl) CPu following prolonged abstinence. In this study, we tested the hypothesis that antisense gene knockdown of Arc within the dlCPu would alter cocaine-seeking. Initial studies showed that a single infusion of Arc antisense oligodeoxynucleotide (ODN) into the dlCPu significantly attenuated the induction of Arc mRNA and Arc protein by a single cocaine exposure (20 mg/kg i.p.) compared to scrambled-ODN-infused controls. In cocaine self-administering rats, infusion of Arc antisense ODN into the dlCPu 3 h prior to a test of context-driven drug-seeking significantly attenuated Arc protein induction, but failed to alter responding during testing, suggesting striatal Arc does not facilitate context-induced drug-seeking following prolonged abstinence. However, Arc antisense ODN infusion blunted the decrease in responding during subsequent 1-h extinction tests 24 and 48 h later. Following re-exposure to a cocaine-paired context, surface expression of the AMPA-type glutamate receptor GluR1 was significantly reduced whereas GluR2 was significantly increased in the dlCPu, independent of Arc antisense ODN infusion. Together, these findings indicate an important role for Arc in neuroadaptations within brain regions responsible for drug-seeking after abstinence and direct attention to changes occurring within striatal circuitry that are necessary to break down the habitual behaviour that leads to relapse.

  4. [Neurologic complications of cocaine abuse].

    Science.gov (United States)

    Van Viet, H; Chevalier, P; Sereni, C; Bornet, P; Bautier, P; Degos, C F; Rullière, R

    1990-06-02

    Cocaine is increasingly used by drug addicts. It is considered harmless, but numerous, varied and often serious complications due to its abuse have been published. Among these, neurological complications are in the forefront. They include generalized or partial epileptic seizures, ischaemic or haemorrhagic cerebral vascular accidents, visual loss caused by optic neuropathy or by retinal artery occlusion, headaches and exacerbation of tics. Infections of the central nervous system are possible via endocarditis or septicaemia of venous or nasal origin. Neurological disorders may also occur as a consequence of a major cardiovascular complication induced by cocaine (myocardial infarction and/or dysrhythmia, aortic dissection). These neurological complications are unpredictable, and they weigh heavily on the functional and sometimes vital prognosis in habitual or occasional cocaine abusers.

  5. Locus coeruleus kappa-opioid receptors modulate reinstatement of cocaine place preference through a noradrenergic mechanism.

    Science.gov (United States)

    Al-Hasani, Ream; McCall, Jordan G; Foshage, Audra M; Bruchas, Michael R

    2013-11-01

    Activation of kappa-opioid receptors (KORs) in monoamine circuits results in dysphoria-like behaviors and stress-induced reinstatement of drug seeking in both conditioned place preference (CPP) and self-administration models. Noradrenergic (NA) receptor systems have also been implicated in similar behaviors. Dynorphinergic projections terminate within the locus coeruleus (LC), a primary source of norepinephrine in the forebrain, suggesting a possible link between the NA and dynorphin/kappa opioid systems, yet the implications of these putative interactions have not been investigated. We isolated the necessity of KORs in the LC in kappa opioid agonist (U50,488)-induced reinstatement of cocaine CPP by blocking KORs in the LC with NorBNI (KOR antagonist). KOR-induced reinstatement was significantly attenuated in mice injected with NorBNI in the LC. To determine the sufficiency of KORs in the LC on U50,488-induced reinstatement of cocaine CPP, we virally re-expressed KORs in the LC of KOR knockout mice. We found that KORs expression in the LC alone was sufficient to partially rescue KOR-induced reinstatement. Next we assessed the role of NA signaling in KOR-induced reinstatement of cocaine CPP in the presence and absence of a α2-agonist (clonidine), β-adrenergic receptor antagonist (propranolol), and β(1)- and β(2)-antagonist (betaxolol and ICI-118,551 HCl). Both the blockade of postsynaptic β(1)-adrenergic receptors and the activation of presynaptic inhibitory adrenergic autoreceptors selectively potentiated the magnitude of KOR-induced reinstatement of cocaine CPP but not cocaine-primed CPP reinstatement. Finally, viral restoration of KORs in the LC together with β-adrenergic receptor blockade did not potentiate KOR-induced reinstatement to cocaine CPP, suggesting that adrenergic receptor interactions occur at KOR-expressing regions external to the LC. These results identify a previously unknown interaction between KORs and NA systems and suggest a NA

  6. Brugada Pattern Electrocardiogram Unmasked with Cocaine Ingestion

    Directory of Open Access Journals (Sweden)

    M. Chadi Alraies

    2013-01-01

    Full Text Available Cocaine is considered a leading cause of drug-related deaths. This is usually sudden, unwitnessed, and without prodromal features. It has been reported that in-hospital mortality is close to 2%. Cocaine has powerful central nervous system effects1 and acute cocaine overdose has been associated with hyperthermia, agitation, paranoid ideation, status epilepticus, ventricular fibrillation, ventricular tachycardia, and myocardial infarction (MI. The mechanisms of cocaine-related death remain poorly understood. We report a patient who survived massive cocaine ingestion with psychomotor agitation and generalized seizures followed by asystolic cardiac arrest and transient Brugada pattern on electrocardiogram (ECG.

  7. Cocaine distribution in wild Erythroxylum species.

    Science.gov (United States)

    Bieri, Stefan; Brachet, Anne; Veuthey, Jean-Luc; Christen, Philippe

    2006-02-20

    Cocaine distribution was studied in leaves of wild Erythroxylum species originating from Bolivia, Brazil, Ecuador, Paraguay, Peru, Mexico, USA, Venezuela and Mauritius. Among 51 species, 28 had never been phytochemically investigated before. Cocaine was efficiently and rapidly extracted with methanol, using focused microwaves at atmospheric pressure, and analysed without any further purification by capillary gas chromatography coupled to mass spectrometry. Cocaine was reported for the first time in 14 species. Erythroxylum laetevirens was the wild species with the highest cocaine content. Its qualitative chromatographic profile also revealed other characteristic tropane alkaloids. Finally, its cocaine content was compared to those of two cultivated coca plants as well as with a coca tea bag sample.

  8. Intravenous paracetamol (acetaminophen).

    Science.gov (United States)

    Duggan, Sean T; Scott, Lesley J

    2009-01-01

    Intravenous paracetamol (rINN)/intravenous acetaminophen (USAN) is an analgesic and antipyretic agent, recommended worldwide as a first-line agent for the treatment of pain and fever in adults and children. In double-blind clinical trials, single or multiple doses of intravenous paracetamol 1 g generally provided significantly better analgesic efficacy than placebo treatment (as determined by primary efficacy endpoints) in adult patients who had undergone dental, orthopaedic or gynaecological surgery. Furthermore, where evaluated, intravenous paracetamol 1 g generally showed similar analgesic efficacy to a bioequivalent dose of propacetamol, and a reduced need for opioid rescue medication. In paediatric surgical patients, recommended doses of intravenous paracetamol 15 mg/kg were not significantly different from propacetamol 30 mg/kg for the treatment of pain, and showed equivocal analgesic efficacy compared with intramuscular pethidine 1 mg/kg in several randomized, active comparator-controlled studies. In a randomized, noninferiority study in paediatric patients with an infection-induced fever, intravenous paracetamol 15 mg/kg treatment was shown to be no less effective than propacetamol 30 mg/kg in terms of antipyretic efficacy. Intravenous paracetamol was well tolerated in clinical trials, having a tolerability profile similar to placebo. Additionally, adverse reactions emerging from the use of the intravenous formulation of paracetamol are extremely rare (<1/10 000). [table: see text].

  9. ANCA-positive vasculitis induced by levamisole-adulterated cocaine and nephrotic syndrome: The kidney as an unusual target

    Science.gov (United States)

    Álvarez Díaz, Hortensia; Marińo Callejo, Ana Isabel; García Rodríguez, José Francisco; Rodríguez Pazos, Laura; Gómez Buela, Inmaculada; Bermejo Barrera, Ana María

    2013-01-01

    Patient: Male, 36 Final Diagnosis: Levamisole-induced vasculopathy Symptoms: Purpuric skin lesions Medication: Levamisole Clinical Procedure: — Specialty: Internal Medicine Objective: Unusual clinical course Background: Levamisole has been detected in seized cocaine samples and a levamisole-induced vasculopathy (LIV) has been described, mainly focused on skin. Case Report: A 36-year-old Caucasian man with history of antibodies to hepatitis C infection (negative hepatitis C virus RNA and negative HIV serology), smoking, and intravenous use of cocaine and brown heroin, presented to the hospital with purpuric skin lesions on extremities and earlobes. One month before the current presentation, a skin punch biopsy of one of these lesions was performed, showing histopathologic findings suggestive of mixed cryoglobulinemia. Laboratory testing revealed leukopenia, renal failure, and nephrotic syndrome. Antimyeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) were positive. The previous skin punch biopsy was revised and demonstrated pathologic findings consistent with leukocytoclastic vasculitis. An analysis of a cocaine sample for personal use, provided by the patient, was performed using mass spectrometry-gas chromatography and levamisole was detected. Three boluses of intravenous methylprednisolone were administered, followed by oral prednisone 1 mg/Kg per day. Skin lesions and renal function improved. Conclusions: To our knowledge, this is the first report of nephrotic syndrome induced by levamisole-adulterated cocaine, proven by cocaine sample toxicology. Lack of renal biopsy is a limitation of this report. PMID:24478818

  10. Cocaine use and the breastfeeding mother.

    Science.gov (United States)

    Jones, Wendy

    2015-01-01

    Cocaine is the second most commonly used illicit drug. Use in pregnancy and breastfeeding may have severe consequences for the baby due to its pharmacokinetic properties. Midwives need to be aware of the prolonged action of cocaine and be alert to the possibility of cocaine toxicity if a baby is excessively irritable and tachycardic. Euphoric highs are brief but breast milk and urine remain positive for long periods. Infant urine following exposure to cocaine via breast milk may remain positive for up to 60 hours. Mothers who snort cocaine should pump and dump breast milk for 24-48 hours. Passive inhalation of crack cocaine smoke may also result in infants with positive toxicology screens. Cocaine powder should never be applied to the nipples of breastfeeding mothers.

  11. Oral Self-Administration Of EtOH In Transgenic Mice Lacking Beta-Endorphin

    Directory of Open Access Journals (Sweden)

    Stephani Allen

    2007-01-01

    Full Text Available EtOH modifies the production and/or release of endogenous opioid peptides, including -endorphin (Gianoulakis, 2004; Przewlocka et al., 1994; Schulz et al., 1980. Opioids subsequently influence the reinforcing properties of EtOH and the development of alcoholism (Terenius, 1996; Van Ree, 1996. In this study, beta-endorphin deficient mutant mice were used to examine the effects of a specific opioid peptide on EtOH consumption. Mice were obtained from The Jackson Laboratory, Bar Harbor, ME, USA. Male and female, adult naïve mice were single housed in Plexiglas cages with corn cob bedding and ad lib access to food (mouse chow and water. A two-bottle free choice EtOH oral self-administration paradigm was administered to homozygous mutant mice (void of all beta-endorphin, heterozygous mice (50% beta-endorphin expression, and sibling wildtype mice (C57BL/6J. Subjects received increasing concentrations of EtOH (0%, 3%, 6%, 12%, and 15% each given over an eight day span, and were evaluated for preference and consumption each day. Bottles were switched every other day to avoid the development of a side preference. Overall, females drank more than males. Homozygous mutant mice (KO showed decreased preference for EtOH at all concentrations, and self-administered significantly less than heterozygous mice (HT and wildtype mice (C57. The HTs had a tendency to drink the most followed by the C57s, and the KOs drank the least. These data support the hypothesis that beta-endorphin influences the reinforcing effects of EtOH.

  12. Cocaine Hoppers : The Nigerian Involvement in the Global Cocaine Trade

    NARCIS (Netherlands)

    Oboh, Jude Roys

    2016-01-01

    In recent decades, Nigerian criminal drug ‘barons’ and ‘gangs’ have come to dominate international cocaine trafficking via West Africa to destination countries globally, a trend that presents a serious security threat to Africa and the world. This work provides empirical evidence to define and

  13. Cocaine Hoppers : The Nigerian Involvement in the Global Cocaine Trade

    NARCIS (Netherlands)

    Oboh, Jude Roys

    2016-01-01

    In recent decades, Nigerian criminal drug ‘barons’ and ‘gangs’ have come to dominate international cocaine trafficking via West Africa to destination countries globally, a trend that presents a serious security threat to Africa and the world. This work provides empirical evidence to define and expla

  14. Pulmonary alterations in cocaine users

    Directory of Open Access Journals (Sweden)

    Mário Terra Filho

    Full Text Available CONTEXT: Brazilian researchers have recently recognized a marked increase in the number of people using abusable drugs and the consequences of this habit. It has become a major public health problem in a potentially productive segment of the general population. In the last few years, several medical articles have given special emphasis to pulmonary complications related to cocaine use. This review is based on this information and experience acquired with groups of cocaine users. OBJECTIVE: To present to physicians the pulmonary aspects of cocaine use and warn about the various effects this drug has on the respiratory system, stressing those related to long-term use. DESIGN: Narrative review. METHOD: Pulmonary complications are described. These may include infections (Staphylococcus aureus, pulmonary tuberculosis, acquired immunodeficiency syndrome/aids, etc., aspiration pneumonia, lung abscess, empyema, septic embolism, non-cardiogenic pulmonary edema, barotrauma, pulmonary granulomatosis, bronchiolitis obliterans and organizing pneumonia, pneumonitis and interstitial fibrosis, pneumonitis hypersensitivity, lung infiltrates and eosinophilia in individuals with bronchial hyperreactivity, diffuse alveolar hemorrhage, vasculitis, pulmonary infarction, pulmonary hypertension and alterations in gas exchange. It is concluded that physicians should give special attention to the various pulmonary and clinical manifestations related to cocaine use, particularly in young patients.

  15. Non-fatal cocaine overdose among injecting and non-injecting cocaine users in Sydney, Australia.

    Science.gov (United States)

    Kaye, Sharlene; Darke, Shane

    2004-10-01

    To investigate the frequency of non-fatal cocaine overdose, and responses to overdoses, among injecting and non-injecting cocaine users. Cross-sectional study. Sydney, Australia. Two hundred current cocaine users. Structured interview. Thirteen per cent of the sample had overdosed on cocaine, 7% in the preceding 12 months. Cocaine injectors were more likely to have overdosed, both ever (17 v 6%) and in the preceding 12 months (9 v 3%). The most common symptoms of overdose were palpitations (68%), intense sweating (44%) and seizures (40%). The use of other drugs in combination with cocaine prior to the most recent overdose was prevalent (64%), most commonly opioids (40%), alcohol (24%) and cannabis (24%). Those who had overdosed were more likely to be female, had longer cocaine use careers, had used more cocaine in the preceding month and preceding 6 months, had higher levels of cocaine dependence and more extensive polydrug use. Twenty-four per cent had witnessed a cocaine overdose, 13% in the preceding 12 months. Injectors were more likely to have witnessed overdoses, both ever (35% v 8%) and in the preceding 12 months (20% v 3%). Experience of, and exposure to, overdose were not rare events. Cocaine users need to be aware of the possibility and nature of overdose, and that cocaine overdose can occur irrespective of method of use. There is a need to emphasise the potential danger of combining cocaine with other drugs.

  16. Noribogaine, but not 18-MC, exhibits similar actions as ibogaine on GDNF expression and ethanol self-administration.

    OpenAIRE

    2010-01-01

    Carnicella S present adress: Grenoble Institut des Neurosciences, Inserm U836; International audience; Ibogaine is a naturally occurring alkaloid that has been reported to decrease various adverse phenotypes associated with exposure to drugs of abuse and alcohol in human and rodent models. Unfortunately, ibogaine cannot be used as a medication to treat addiction because of severe side effects. Previously, we reported that the desirable actions of ibogaine to reduce self-administration of, and...

  17. Orexin-1 and orexin-2 receptor antagonists reduce ethanol self-administration in high-drinking rodent models

    Directory of Open Access Journals (Sweden)

    Rachel Ivy Anderson

    2014-02-01

    Full Text Available To examine the role of orexin-1 and orexin-2 receptor activity on ethanol self-administration, compounds that differentially target orexin (OX receptor subtypes were assessed in various self-administration paradigms using high-drinking rodent models. Effects of the OX1 antagonist SB334867, the OX2 antagonist LSN2424100, and the mixed OX1/2 antagonist almorexant (ACT-078573 on home cage ethanol consumption were tested in ethanol-preferring (P rats using a 2-bottle choice procedure. In separate experiments, effects of SB334867, LSN2424100, and almorexant on operant ethanol self-administration were assessed in P rats maintained on a progressive ratio operant schedule of reinforcement. In a third series of experiments, SB334867, LSN2424100, and almorexant were administered to ethanol-preferring C57BL/6J mice to examine effects of OX receptor blockade on ethanol intake in a binge-like drinking (drinking-in-the-dark model. In P rats with chronic home cage free-choice ethanol access, SB334867 and almorexant significantly reduced ethanol intake, but almorexant also reduced water intake, suggesting nonspecific effects on consummatory behavior. In the progressive ratio operant experiments, LSN2424100 and almorexant reduced breakpoints and ethanol consumption in P rats, whereas the almorexant inactive enantiomer and SB334867 did not significantly affect the motivation to consume ethanol. As expected, vehicle-injected mice exhibited binge-like drinking patterns in the drinking-in-the-dark model. All three OX antagonists reduced both ethanol intake and resulting blood ethanol concentrations relative to vehicle-injected controls, but SB334867 and LSN2424100 also reduced sucrose consumption in a different cohort of mice, suggesting nonspecific effects. Collectively, these results contribute to a growing body of evidence indicating that OX1 and OX2 receptor activity influences ethanol self-administration, although the effects may not be selective for ethanol

  18. When a good taste turns bad: Neural mechanisms underlying the emergence of negative affect and associated natural reward devaluation by cocaine.

    Science.gov (United States)

    Carelli, Regina M; West, Elizabeth A

    2014-01-01

    An important feature of cocaine addiction in humans is the emergence of negative affect (e.g., dysphoria, irritability, anhedonia), postulated to play a key role in craving and relapse. Indeed, the DSM-IV recognizes that social, occupational and/or recreational activities become reduced as a consequence of repeated drug use where previously rewarding experiences (e.g., food, job, family) become devalued as the addict continues to seek and use drug despite serious negative consequences. Here, research in the Carelli laboratory is reviewed that examined neurobiological mechanisms that may underlie these processes using a novel animal model. Oromotor responses (taste reactivity) were examined as rats learned that intraoral infusion of a sweet (e.g., saccharin) predicts impending but delayed access to cocaine self-administration. We showed that rats exhibit aversive taste reactivity (i.e., gapes/rejection responses) during infusion of the sweet paired with impending cocaine, similar to aversive responses observed during infusion of quinine, a bitter tastant. Critically, the expression of this pronounced aversion to the sweet predicted the subsequent motivation to self-administer cocaine. Electrophysiology studies show that this shift in palatability corresponds to an alteration in nucleus accumbens (NAc) cell firing; neurons that previously responded with inhibition during infusion of the palatable sweet shifted to excitatory activity during infusion of the cocaine-devalued tastant. This excitatory response profile is typically observed during infusion of quinine, indicating that the once palatable sweet becomes aversive following its association with impending but delayed cocaine, and NAc neurons encode this aversive state. We also review electrochemical studies showing a shift (from increase to decrease) in rapid NAc dopamine release during infusion of the cocaine-paired tastant as the aversive state developed, again, resulting in responses similar to quinine

  19. The dopamine D2 antagonist eticlopride accelerates extinction and delays reacquisition of food self-administration in rats.

    Science.gov (United States)

    Koerber, Jonathon; Goodman, David; Barnes, Jesse L; Grimm, Jeffrey W

    2013-12-01

    Dopamine receptors are implicated in the reinforcing effects of food and drug reinforcement. The purpose of this study was to evaluate whether blocking D2 dopamine receptors during extinction (secondary reinforcement) would affect reacquisition of responding for food pellets (primary reinforcement). Food-restricted rats self-administered (fixed-ratio 1) food pellets in 1-h daily sessions for 7 days. For the next 7 days rats responded in extinction conditions. Before each extinction session rats were injected with saline or the dopamine D2 antagonist eticlopride (0.03 mg/kg, subcutaneously). After the extinction phase, rats were allowed to reacquire food pellet self-administration in seven daily sessions, and received saline or eticlopride before each session. Four treatment groups were represented: saline extinction, saline reacquisition; eticlopride extinction, saline reacquisition; saline extinction, eticlopride reacquisition; and eticlopride extinction, eticlopride reacquisition. Locomotor activity did not differ between eticlopride-treated and saline-treated rats throughout the study. Extinction was accelerated in eticlopride-treated rats. Eticlopride also delayed reacquisition of food self-administration compared with saline-treated rats. Rats administered eticlopride during extinction showed delayed reacquisition and a decreased response rate for food during the reacquisition phase. Indirectly reducing the value of a reinforcer in this way may provide a novel approach for reducing addiction-related food or drug self-administration behaviors.

  20. Metabolic Enzymes of Cocaine Metabolite Benzoylecgonine.

    Science.gov (United States)

    Chen, Xiabin; Zheng, Xirong; Zhan, Max; Zhou, Ziyuan; Zhan, Chang-Guo; Zheng, Fang

    2016-08-19

    Cocaine is one of the most addictive drugs without a U.S. Food and Drug Administration (FDA)-approved medication. Enzyme therapy using an efficient cocaine-metabolizing enzyme is recognized as the most promising approach to cocaine overdose treatment. The actual enzyme, known as RBP-8000, under current clinical development for cocaine overdose treatment is our previously designed T172R/G173Q mutant of bacterial cocaine esterase (CocE). The T172R/G173Q mutant is effective in hydrolyzing cocaine but inactive against benzoylecgonine (a major, biologically active metabolite of cocaine). Unlike cocaine itself, benzoylecgonine has an unusually stable zwitterion structure resistant to further hydrolysis in the body and environment. In fact, benzoylecgonine can last in the body for a very long time (a few days) and, thus, is responsible for the long-term toxicity of cocaine and a commonly used marker for drug addiction diagnosis in pre-employment drug tests. Because CocE and its mutants are all active against cocaine and inactive against benzoylecgonine, one might simply assume that other enzymes that are active against cocaine are also inactive against benzoylecgonine. Here, through combined computational modeling and experimental studies, we demonstrate for the first time that human butyrylcholinesterase (BChE) is actually active against benzoylecgonine, and that a rationally designed BChE mutant can not only more efficiently accelerate cocaine hydrolysis but also significantly hydrolyze benzoylecgonine in vitro and in vivo. This sets the stage for advanced studies to design more efficient mutant enzymes valuable for the development of an ideal cocaine overdose enzyme therapy and for benzoylecgonine detoxification in the environment.

  1. Intragastric fat self-administration is impaired in GPR40/120 double knockout mice.

    Science.gov (United States)

    Sclafani, Anthony; Touzani, Khalid; Ackroff, Karen

    2015-08-01

    Mice acquire strong preferences for flavors paired with intragastric (IG) fat infusions. This IG fat conditioning is attenuated in double knockout (DoKO) mice missing GPR40 and GPR120 fatty acid receptors. Here we determined if GPR40/120 DoKO mice are also impaired in IG fat self-administration in an operant lick task. In daily 1-h sessions the mice were trained with a sipper spout that contained dry food pellets; licks on the spout triggered infusions of IG fat (Intralipid). The training sessions were followed by test sessions with an empty spout. GPR40/120 DoKO mice self-infused more 20% fat than wild type (WT) C57BL/6 mice in training with a food-baited spout (2.4 vs. 2.0kcal/h) but self-infused less 20% fat than WT mice in empty spout tests (1.2 vs. 1.7kcal/h). The DoKO mice also self-infused less 5% fat than WT mice (0.6 vs. 1.3kcal/h) although both groups emitted more licks for 5% fat than 20% fat. The DoKO and WT mice did not differ, however, in their self-infusion of 12.5% glucose (1.5 vs. 1.6kcal/h), which is isocaloric to 5% fat. A second 5% IL test showed that the DoKO mice reverted to a reduced self-infusion compared to WT mice. When the infusion was shifted to water, WT mice reduced licking in the first extinction session, whereas DoKO mice were less sensitive to the absence of infused fat. Our results indicate that post-oral GPR40/120 signaling is not required to process IG fat infusions in food-baited spout training sessions but contributes to post-oral fat reinforcement in empty spout tests and flavor conditioning tests.

  2. The novel recreational drug 3,4-methylenedioxypyrovalerone (MDPV) is a potent psychomotor stimulant: self-administration and locomotor activity in rats.

    Science.gov (United States)

    Aarde, S M; Huang, P K; Creehan, K M; Dickerson, T J; Taffe, M A

    2013-08-01

    Recreational use of the cathinone derivative 3,4-methylenedioxypyrovalerone (MDPV; "bath salts") has increased worldwide in past years, accompanied by accounts of health and legal problems in the popular media and efforts to criminalize possession in numerous jurisdictions. Minimal information exists on the effects of MDPV in laboratory models. This study determined the effects of MDPV, alongside those of the better studied stimulant d-methamphetamine (METH), using rodent models of intravenous self-administration (IVSA), thermoregulation and locomotor activity. Male Wistar rats were trained to self-administer MDPV or METH (0.05 mg/kg/infusion, i.v.) or were prepared with radiotelemetry implants for the assessment of body temperature and activity responses to MDPV or METH (0-5.6 mg/kg s.c.). METH and MDPV were consistently self-administered within 10 training sessions (mg/kg/h; METH Mean = 0.4 and Max = 1.15; MDPV Mean = 0.9 and Max = 5.8). Dose-substitution studies demonstrated that behavior was sensitive to dose for both drugs, but MDPV (0.01-0.50 mg/kg/inf) showed greater potency and efficacy than METH (0.1-0.25 mg/kg/inf). In addition, both MDPV and METH increased locomotor activity at lower doses (0.5-1.0 mg/kg, s.c.) and transiently decreased activity at the highest dose (5.6 mg/kg, s.c.). Body temperature increased monotonically with increasing doses of METH but MDPV had a negligible effect on temperature. Stereotypy was associated with relatively high self-administered cumulative doses of MDPV (∼1.5 mg/kg/h) as well as with non-contingent MDPV administration wherein the intensity and duration of stereotypy increased as MDPV dose increased. Thus, MDPV poses a substantial threat for compulsive use that is potentially greater than that for METH. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Activation of exchange protein activated by cAMP in the rat basolateral amygdala impairs reconsolidation of a memory associated with self-administered cocaine.

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    Xun Wan

    Full Text Available The intracellular mechanisms underlying memory reconsolidation critically involve cAMP signaling. These events were originally attributed to PKA activation by cAMP, but the identification of Exchange Protein Activated by cAMP (Epac, as a distinct mediator of cAMP signaling, suggests that cAMP-regulated processes that subserve memory reconsolidation are more complex. Here we investigated how activation of Epac with 8-pCPT-cAMP (8-CPT impacts reconsolidation of a memory that had been associated with cocaine self-administration. Rats were trained to lever press for cocaine on an FR-1 schedule, in which each cocaine delivery was paired with a tone+light cue. Lever pressing was then extinguished in the absence of cue presentations and cocaine delivery. Following the last day of extinction, rats were put in a novel context, in which the conditioned cue was presented to reactivate the cocaine-associated memory. Immediate bilateral infusions of 8-CPT into the basolateral amygdala (BLA following reactivation disrupted subsequent cue-induced reinstatement in a dose-dependent manner, and modestly reduced responding for conditioned reinforcement. When 8-CPT infusions were delayed for 3 hours after the cue reactivation session or were given after a cue extinction session, no effect on cue-induced reinstatement was observed. Co-administration of 8-CPT and the PKA activator 6-Bnz-cAMP (10 nmol/side rescued memory reconsolidation while 6-Bnz alone had no effect, suggesting an antagonizing interaction between the two cAMP signaling substrates. Taken together, these studies suggest that activation of Epac represents a parallel cAMP-dependent pathway that can inhibit reconsolidation of cocaine-cue memories and reduce the ability of the cue to produce reinstatement of cocaine-seeking behavior.

  4. Levamisole and cocaine synergism: a prevalent adulterant enhances cocaine's action in vivo

    OpenAIRE

    Tallarida, Christopher S.; Egan, Erin; Alejo, Gissel D.; Raffa, Robert; Tallarida, Ronald J.; Rawls, Scott M.

    2014-01-01

    Levamisole is estimated by the Drug Enforcement Agency (DEA) to be present in about 80% of cocaine seized in the United States and linked to debilitating, and sometimes fatal, immunologic effects in cocaine abusers. One explanation for the addition of levamisole to cocaine is that it increases the amount of product and enhances profits. An alternative possibility, and one investigated here, is that levamisole alters cocaine's action in vivo. We specifically investigated effects of levamisole ...

  5. Reduced attentional scope in cocaine polydrug users.

    Directory of Open Access Journals (Sweden)

    Lorenza S Colzato

    Full Text Available Cocaine is Europe's second preferred recreational drug after cannabis but very little is known about possible cognitive impairments in the upcoming type of recreational cocaine user (monthly consumption. We asked whether recreational use of cocaine impacts early attentional selection processes. Cocaine-free polydrug controls (n = 18 and cocaine polydrug users (n = 18 were matched on sex, age, alcohol consumption, and IQ (using the Raven's progressive matrices, and were tested by using the Global-Local task to measure the scope of attention. Cocaine polydrug users attended significantly more to local aspects of attended events, which fits with the idea that a reduced scope of attention may be associated with the perpetuation of the use of the drug.

  6. Cocaine disinhibits dopamine neurons in the ventral tegmental area via use-dependent blockade of GABA neuron voltage-sensitive sodium channels.

    Science.gov (United States)

    Steffensen, Scott C; Taylor, Seth R; Horton, Malia L; Barber, Elise N; Lyle, Laura T; Stobbs, Sarah H; Allison, David W

    2008-11-01

    The aim of this study was to evaluate the effects of cocaine on gamma-aminobutyric acid (GABA) and dopamine (DA) neurons in the ventral tegmental area (VTA). Utilizing single-unit recordings in vivo, microelectrophoretic administration of DA enhanced the firing rate of VTA GABA neurons via D2/D3 DA receptor activation. Lower doses of intravenous cocaine (0.25-0.5 mg/kg), or the DA transporter (DAT) blocker methamphetamine, enhanced VTA GABA neuron firing rate via D2/D3 receptor activation. Higher doses of cocaine (1.0-2.0 mg/kg) inhibited their firing rate, which was not sensitive to the D2/D3 antagonist eticlopride. The voltage-sensitive sodium channel (VSSC) blocker lidocaine inhibited the firing rate of VTA GABA neurons at all doses tested (0.25-2.0 mg/kg). Cocaine or lidocaine reduced VTA GABA neuron spike discharges induced by stimulation of the internal capsule (ICPSDs) at dose levels 0.25-2 mg/kg (IC(50) 1.2 mg/kg). There was no effect of DA or methamphetamine on ICPSDs, or of DA antagonists on cocaine inhibition of ICPSDs. In VTA GABA neurons in vitro, cocaine reduced (IC(50) 13 microm) current-evoked spikes and TTX-sensitive sodium currents in a use-dependent manner. In VTA DA neurons, cocaine reduced IPSCs (IC(50) 13 microm), increased IPSC paired-pulse facilitation and decreased spontaneous IPSC frequency, without affecting miniature IPSC frequency or amplitude. These findings suggest that cocaine acts on GABA neurons to reduce activity-dependent GABA release on DA neurons in the VTA, and that cocaine's use-dependent blockade of VTA GABA neuron VSSCs may synergize with its DAT inhibiting properties to enhance mesolimbic DA transmission implicated in cocaine reinforcement.

  7. Understanding the Functional Plasticity in Neural Networks of the Basal Ganglia in Cocaine Use Disorder: A Role for Allosteric Receptor-Receptor Interactions in A2A-D2 Heteroreceptor Complexes

    Directory of Open Access Journals (Sweden)

    Dasiel O. Borroto-Escuela

    2016-01-01

    Full Text Available Our hypothesis is that allosteric receptor-receptor interactions in homo- and heteroreceptor complexes may form the molecular basis of learning and memory. This principle is illustrated by showing how cocaine abuse can alter the adenosine A2AR-dopamine D2R heterocomplexes and their receptor-receptor interactions and hereby induce neural plasticity in the basal ganglia. Studies with A2AR ligands using cocaine self-administration procedures indicate that antagonistic allosteric A2AR-D2R heterocomplexes of the ventral striatopallidal GABA antireward pathway play a significant role in reducing cocaine induced reward, motivation, and cocaine seeking. Anticocaine actions of A2AR agonists can also be produced at A2AR homocomplexes in these antireward neurons, actions in which are independent of D2R signaling. At the A2AR-D2R heterocomplex, they are dependent on the strength of the antagonistic allosteric A2AR-D2R interaction and the number of A2AR-D2R and A2AR-D2R-sigma1R heterocomplexes present in the ventral striatopallidal GABA neurons. It involves a differential cocaine-induced increase in sigma1Rs in the ventral versus the dorsal striatum. In contrast, the allosteric brake on the D2R protomer signaling in the A2AR-D2R heterocomplex of the dorsal striatopallidal GABA neurons is lost upon cocaine self-administration. This is potentially due to differences in composition and allosteric plasticity of these complexes versus those in the ventral striatopallidal neurons.

  8. Understanding the Functional Plasticity in Neural Networks of the Basal Ganglia in Cocaine Use Disorder: A Role for Allosteric Receptor-Receptor Interactions in A2A-D2 Heteroreceptor Complexes

    Science.gov (United States)

    Borroto-Escuela, Dasiel O.; Wydra, Karolina; Pintsuk, Julia; Narvaez, Manuel; Corrales, Fidel; Zaniewska, Magdalena; Agnati, Luigi F.; Franco, Rafael; Tanganelli, Sergio; Filip, Malgorzata

    2016-01-01

    Our hypothesis is that allosteric receptor-receptor interactions in homo- and heteroreceptor complexes may form the molecular basis of learning and memory. This principle is illustrated by showing how cocaine abuse can alter the adenosine A2AR-dopamine D2R heterocomplexes and their receptor-receptor interactions and hereby induce neural plasticity in the basal ganglia. Studies with A2AR ligands using cocaine self-administration procedures indicate that antagonistic allosteric A2AR-D2R heterocomplexes of the ventral striatopallidal GABA antireward pathway play a significant role in reducing cocaine induced reward, motivation, and cocaine seeking. Anticocaine actions of A2AR agonists can also be produced at A2AR homocomplexes in these antireward neurons, actions in which are independent of D2R signaling. At the A2AR-D2R heterocomplex, they are dependent on the strength of the antagonistic allosteric A2AR-D2R interaction and the number of A2AR-D2R and A2AR-D2R-sigma1R heterocomplexes present in the ventral striatopallidal GABA neurons. It involves a differential cocaine-induced increase in sigma1Rs in the ventral versus the dorsal striatum. In contrast, the allosteric brake on the D2R protomer signaling in the A2AR-D2R heterocomplex of the dorsal striatopallidal GABA neurons is lost upon cocaine self-administration. This is potentially due to differences in composition and allosteric plasticity of these complexes versus those in the ventral striatopallidal neurons. PMID:27872762

  9. Impaired insight in cocaine addiction: laboratory evidence and effects on cocaine-seeking behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, S.J.; Moeller, S.J.; Maloney, T.; Parvaz, M.A.; Alia-Klein, N.; Woicik, P.A.; Telang, F.; Wang, G.-J.; Volkow, N.D.; Goldstein, R.Z.

    2010-04-15

    Neuropsychiatric disorders are often characterized by impaired insight into behaviour. Such an insight deficit has been suggested, but never directly tested, in drug addiction. Here we tested for the first time this impaired insight hypothesis in drug addiction, and examined its potential association with drug-seeking behaviour. We also tested potential modulation of these effects by cocaine urine status, an individual difference known to impact underlying cognitive functions and prognosis. Sixteen cocaine addicted individuals testing positive for cocaine in urine, 26 cocaine addicted individuals testing negative for cocaine in urine, and 23 healthy controls completed a probabilistic choice task that assessed objective preference for viewing four types of pictures (pleasant, unpleasant, neutral and cocaine). This choice task concluded by asking subjects to report their most selected picture type; correspondence between subjects self-reports with their objective choice behaviour provided our index of behavioural insight. Results showed that the urine positive cocaine subjects exhibited impaired insight into their own choice behaviour compared with healthy controls; this same study group also selected the most cocaine pictures (and fewest pleasant pictures) for viewing. Importantly, however, it was the urine negative cocaine subjects whose behaviour was most influenced by insight, such that impaired insight in this subgroup only was associated with higher cocaine-related choice on the task and more severe actual cocaine use. These findings suggest that interventions to enhance insight may decrease drug-seeking behaviour, especially in urine negative cocaine subjects, potentially to improve their longer-term clinical outcomes.

  10. Calcium-permeable AMPA receptors in the VTA and nucleus accumbens after cocaine exposure: When, how and why?

    Directory of Open Access Journals (Sweden)

    Marina E Wolf

    2012-06-01

    Full Text Available In animal models of drug addiction, cocaine exposure has been shown to increase levels of calcium-permeable AMPA receptors (CP-AMPARs in two brain regions that are critical for motivation and reward - the ventral tegmental area (VTA and the nucleus accumbens (NAc. This review compares CP-AMPAR plasticity in the two brain regions and addresses its functional significance. In VTA dopamine neurons, cocaine exposure results in synaptic insertion of high conductance CP-AMPARs in exchange for lower conductance calcium-impermeable AMPARs (CI-AMPARs. This plasticity is rapid (hours, GluA2-dependent, and can be observed with a single cocaine injection. In addition to strengthening synapses and altering Ca2+ signaling, CP-AMPAR insertion affects subsequent induction of plasticity at VTA synapses. However, CP-AMPAR insertion is unlikely to mediate the increased dopamine cell activity that occurs during early withdrawal from cocaine exposure. Within the VTA, the group I metabotropic glutamate receptor mGluR1 exerts a negative influence on CP-AMPAR accumulation. Acutely, mGluR1 stimulation elicits a form of LTD resulting from CP-AMPAR removal and CI-AMPAR insertion. In medium spiny neurons (MSNs of the NAc, extended access cocaine self-administration is required to increase CP-AMPAR levels. This is first detected after approximately a month of withdrawal and then persists. Once present in NAc synapses, CP-AMPARs mediate the expression of incubation of cue-induced cocaine craving. The mechanism of their accumulation may be GluA1-dependent, which differs from that observed in the VTA. However, similar to VTA, mGluR1 stimulation removes CP-AMPARs from MSN synapses. Loss of mGluR1 tone during cocaine withdrawal may contribute to CP-AMPAR accumulation in the NAc. Thus, results in both brain regions point to the possibility of using positive modulators of mGluR1 as a treatment for cocaine addiction.

  11. Cocaine/levamisole-induced systemic vasculitis with retiform purpura and pauci-immune glomerulonephritis.

    Science.gov (United States)

    Veronese, F V; Dode, R S O; Friderichs, M; Thomé, G G; da Silva, D R; Schaefer, P G; Sebben, V C; Nicolella, A R; Barros, E J G

    2016-01-01

    Levamisole has been increasingly used as an adulterant of cocaine in recent years, emerging as a public health challenge worldwide. Levamisole-associated toxicity manifests clinically as a systemic vasculitis, consisting of cutaneous, hematological, and renal lesions, among others. Purpura retiform, cutaneous necrosis, intravascular thrombosis, neutropenia, and less commonly crescentic nephritis have been described in association with anti-neutrophil cytoplasmic antibodies (ANCAs) and other autoantibodies. Here we report the case of a 49-year-old male who was a chronic cocaine user, and who presented spontaneous weight loss, arthralgia, and 3 weeks before admission purpuric skin lesions in the earlobes and in the anterior thighs. His laboratory tests on admission showed serum creatinine of 4.56 mg/dL, white blood count 3,800/μL, hemoglobin 7.3 g/dL, urinalysis with 51 white blood cells/μL and 960 red blood cells/μL, and urine protein-to-creatinine ratio 1.20. Serum ANCA testing was positive (>1:320), as well as serum anti-myeloperoxidase and anti-proteinase 3 antibodies. Urine toxicology screen was positive for cocaine and levamisole, with 62.8% of cocaine, 32.2% of levamisole, and 5% of an unidentified substance. Skin and renal biopsies were diagnostic for leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis, respectively. The patient showed a good clinical response to cocaine abstinence, and use of corticosteroids and intravenous cyclophosphamide. Last serum creatinine was 1.97 mg/dL, white blood cell count 7,420/μL, and hemoglobin level 10.8 g/dL. In levamisole-induced systemic vasculitis, the early institution of cocaine abstinence, concomitant with the use of immunosuppressive drugs in severe cases, may prevent permanent end organ damage and associate with better clinical outcomes.

  12. Cocaine/levamisole-induced systemic vasculitis with retiform purpura and pauci-immune glomerulonephritis

    Directory of Open Access Journals (Sweden)

    F.V. Veronese

    2016-01-01

    Full Text Available Levamisole has been increasingly used as an adulterant of cocaine in recent years, emerging as a public health challenge worldwide. Levamisole-associated toxicity manifests clinically as a systemic vasculitis, consisting of cutaneous, hematological, and renal lesions, among others. Purpura retiform, cutaneous necrosis, intravascular thrombosis, neutropenia, and less commonly crescentic nephritis have been described in association with anti-neutrophil cytoplasmic antibodies (ANCAs and other autoantibodies. Here we report the case of a 49-year-old male who was a chronic cocaine user, and who presented spontaneous weight loss, arthralgia, and 3 weeks before admission purpuric skin lesions in the earlobes and in the anterior thighs. His laboratory tests on admission showed serum creatinine of 4.56 mg/dL, white blood count 3,800/μL, hemoglobin 7.3 g/dL, urinalysis with 51 white blood cells/μL and 960 red blood cells/μL, and urine protein-to-creatinine ratio 1.20. Serum ANCA testing was positive (>1:320, as well as serum anti-myeloperoxidase and anti-proteinase 3 antibodies. Urine toxicology screen was positive for cocaine and levamisole, with 62.8% of cocaine, 32.2% of levamisole, and 5% of an unidentified substance. Skin and renal biopsies were diagnostic for leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis, respectively. The patient showed a good clinical response to cocaine abstinence, and use of corticosteroids and intravenous cyclophosphamide. Last serum creatinine was 1.97 mg/dL, white blood cell count 7,420/μL, and hemoglobin level 10.8 g/dL. In levamisole-induced systemic vasculitis, the early institution of cocaine abstinence, concomitant with the use of immunosuppressive drugs in severe cases, may prevent permanent end organ damage and associate with better clinical outcomes.

  13. Reaction Mechanism for Cocaine Esterase-Catalyzed Hydrolyses of (+)- and (−)-Cocaine: Unexpected Common Rate-Determining Step

    OpenAIRE

    Liu, Junjun; Zhao, Xinyun; Yang, Wenchao; Zhan, Chang-Guo

    2011-01-01

    First-principles quantum mechanical/molecular mechanical (QM/MM)-free energy (FE) calculations have been performed to examine catalytic mechanism for cocaine esterase (CocE)-catalyzed hydrolysis of (+)-cocaine in comparison with CocE-catalyzed hydrolysis of (−)-cocaine. It has been shown that the acylation of (+)-cocaine consists of nucleophilic attack of hydroxyl group of Ser117 on carbonyl carbon of (+)-cocaine benzoyl ester and the dissociation of (+)-cocaine benzoyl ester. The first react...

  14. Cocaine challenge enhances release of neuroprotective amino acid taurine in the striatum of chronic cocaine treated rats: a microdialysis study

    OpenAIRE

    Yablonsky-Alter, Elena; Agovic, Mervan S.; Gashi, Eleonora; Lidsky, Theodore I.; Friedman, Eitan; Banerjee, Shailesh P.

    2009-01-01

    Drug addiction is a serious public health problem. There is increasing evidence on the involvement of augmented glutamatergic transmission in cocaine-induced addiction and neurotoxicity. We investigated effects of acute or chronic cocaine administration and cocaine challenge following chronic cocaine exposure on the release of excitotoxic glutamate and neuroprotective taurine in the rat striatum by microdialysis. Cocaine challenge, following withdrawal after repeated cocaine exposure markedly...

  15. Effects of a selectively bred novelty-seeking phenotype on the motivation to take cocaine in male and female rats

    Directory of Open Access Journals (Sweden)

    Cummings Jennifer A

    2011-03-01

    Full Text Available Abstract Background Gender and enhanced novelty reactivity can predispose certain individuals to drug abuse. Previous research in male and female rats selectively bred for high or low locomotor reactivity to novelty found that bred High Responders (bHRs acquire cocaine self-administration more rapidly than bred Low Responders (bLRs and that bHR females in particular self-administered more cocaine than the other groups. The experiments presented here aimed to determine whether an individual's sex and behavioral phenotype interact to affect motivation to take cocaine. Methods We examined motivation for taking cocaine in two experiments using a range of doses on a progressive ratio (PR schedule of responding in bHR or bLR males and females. Additionally, we included a measure of continuing to respond in the absence of reinforcement, a feature of addiction that has been recently incorporated into tests of animal models on the basis of the criteria for substance use disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Statistical analyses were performed using PASW Statistics 18.0 software. Data were analyzed using repeated-measures analysis of variance followed by a Bonferroni correction post hoc test when applicable. Results We found sex differences as well as effects of novelty reactivity on the motivation to self-administer cocaine. Specifically, females demonstrated higher breaking points on the PR schedule compared with males, regardless of phenotype, and bHR males and females exhibited higher motivation than bLR animals at a number of the doses studied. Conclusions An individual's sex continues to be a predisposing factor with respect to drug abuse liability and can be compounded by additional individual differences such as reactivity to novelty.

  16. Molecular approaches to treatments for cocaine abuse

    Science.gov (United States)

    Flippen-Anderson, Judith L.; George, Clifford; Deschamps, Jeffrey R.

    2003-02-01

    Cocaine is a potent stimulant of the central nervous system with severe addiction potential. Its abuse is a major problem worldwide. The exact mechanism of action of cocaine is still uncertain but it is known that its reinforcing and stimulant effects are related to its ability to inhibit the membrane bound dopamine transporter (DAT). This paper discusses efforts that are underway to identify ligands for possible use in the treatment of cocaine abuse. Much of this effort has been focussed on understanding cocaine interactions at DAT receptor sites.

  17. [Cocaine-related gastric perforation].

    Science.gov (United States)

    Ring, A; Stein, E; Stern, J

    2010-06-01

    Since the 1980s the abuse of cocaine has been -associated with gastroduodenal perforations in the United States. Here, we report the case of a 28-year-old man who came to our hospital with severe abdominal pain after smoking cocaine. Physical examination revealed generalised abdominal guarding. His X-ray did not show any free intraperitoneal air. However, there was a slightly elevated white blood cell count. Upon laparoscopic exploration of the abdomen, the -patient was found to have a generalised peritonitis secondary to a perforation of the prepyloric anterior wall. The operative procedure consisted of ulcer excision and primary closure with a pyloroplasty as well as an extensive abdominal irrigation after laparotomy.

  18. Effect of Acupuncture on Contents of Tyrosine Hydroxylase and Glial Fibrillary Acidic Protein in Ventral Tegmental Area of Heroin Self-administrating Rats

    Institute of Scientific and Technical Information of China (English)

    ZHU Zhong-chun; HU Jun; XU Ping

    2006-01-01

    目的:探讨海洛因静脉自身给药大鼠中脑腹侧被盖区(VTA),伏隔核(NAc),杏仁核(Amy),前额叶皮层(PFC),黑质(SN),尾壳核(CPu)等脑区内生化功能的改变以及电针的干预作用.方法:建立大鼠海洛因静脉自身给药模型30只,随机分为模型组(n=6),自然戒断组(n=12),电针组(n=12),同时设生理盐水对照组(n=6).自然戒断组中6只大鼠停药戒断7d,另6只大鼠停药戒断14d;电针组停药戒断的同时,每天给予电针治疗,其中6只大鼠治疗7天,另6只大鼠治疗14d;生理盐水组采用生理盐水代替海洛因进行给药训练,余同模型组.采用免疫组化法测定VTA,NAc,SN CPu,Amy,PFC等脑区的神经胶质纤维酸性蛋白(GFAP)及酪氨酸羟化酶(TH)含量.结果:VTA内TH,GFAP含量发生明显上调,NAc内TH, GFAP含量相对下调;而SN, CPu,Amy,PFC内TH, GFAP含量没有改变;电针治疗可加速VTA脑内上调的TH, GFAP含量向正常水平恢复,一定程度逆转受"损伤"的DA神经元.结论:大鼠海洛因依赖时,VTA-NAc DA通路发生了一定程度的生化功能适应性改变;电针对阿片类药物成瘾后VTA内DA神经元"损伤"修复和功能恢复具有一定的促进作用.%Objective: This present study is to investigate the biochemical adaptations in the related brain regions of the mesolimbic dopamine system, such as the ventral tegrnental area (VTA), nucleus accumbens (Nac), amygdale (Amy), prefrontal cortex (PFC) , substantia nigra (SN) and caudateputamen (Cpu) in response to heroin self-administration in rats and observe the effect of electroacupuncture on them. Methods: 2hirty rats were trained by nose-poking response to establish stable intravenous heroin self-administration within 14 days, and then divided randomly into model group (group B) including 6 rats, withdrawal group which were withdrawn from heroin for 1 week (group C, n = 6) and for 2 weeks (group D, n= 6), during which time they only lived in their individual home cages

  19. Manipulating a "cocaine engram" in mice.

    Science.gov (United States)

    Hsiang, Hwa-Lin Liz; Epp, Jonathan R; van den Oever, Michel C; Yan, Chen; Rashid, Asim J; Insel, Nathan; Ye, Li; Niibori, Yosuke; Deisseroth, Karl; Frankland, Paul W; Josselyn, Sheena A

    2014-10-15

    Experience with drugs of abuse (such as cocaine) produces powerful, long-lasting memories that may be important in the development and persistence of drug addiction. The neural mechanisms that mediate how and where these cocaine memories are encoded, consolidated and stored are unknown. Here we used conditioned place preference in mice to examine the precise neural circuits that support the memory of a cocaine-cue association (the "cocaine memory trace" or "cocaine engram"). We found that a small population of neurons (∼10%) in the lateral nucleus of amygdala (LA) were recruited at the time of cocaine-conditioning to become part of this cocaine engram. Neurons with increased levels of the transcription factor CREB were preferentially recruited or allocated to the cocaine engram. Ablating or silencing neurons overexpressing CREB (but not a similar number of random LA neurons) before testing disrupted the expression of a previously acquired cocaine memory, suggesting that neurons overexpressing CREB become a critical hub in what is likely a larger cocaine memory engram. Consistent with theories that coordinated postencoding reactivation of neurons within an engram or cell assembly is crucial for memory consolidation (Marr, 1971; Buzsáki, 1989; Wilson and McNaughton, 1994; McClelland et al., 1995; Girardeau et al., 2009; Dupret et al., 2010; Carr et al., 2011), we also found that post-training suppression, or nondiscriminate activation, of CREB overexpressing neurons impaired consolidation of the cocaine memory. These findings reveal mechanisms underlying how and where drug memories are encoded and stored in the brain and may also inform the development of treatments for drug addiction.

  20. A thermostable bacterial cocaine esterase rapidly eliminates cocaine from brain in nonhuman primates.

    Science.gov (United States)

    Howell, L L; Nye, J A; Stehouwer, J S; Voll, R J; Mun, J; Narasimhan, D; Nichols, J; Sunahara, R; Goodman, M M; Carroll, F I; Woods, J H

    2014-07-01

    A long-acting, thermostable bacterial cocaine esterase (CocE) has been identified that rapidly degrades cocaine with a K(M) of 1.33+0.085 μM. In vivo evaluation of CocE has shown protection against convulsant and lethal effects of cocaine in rodents, confirming the therapeutic potential of CocE against cocaine overdose. However, the current study is the first to evaluate the effects of CocE on cocaine brain levels. Positron emission tomogrpahy neuroimaging of [(11)C]cocaine was used to evaluate the time course of cocaine elimination from brain in the presence and absence of CocE in nonhuman primates. Systemic administration of CocE eliminated cocaine from the rhesus-monkey brain approximately three times faster than control conditions via peripheral actions through attenuating the input function from blood plasma. The efficiency of this process is sufficient to alleviate or prevent adverse central nervous system effects induced by cocaine. Although the present study used tracer doses of cocaine to access brain clearance, these findings further support the development of CocE for the treatment of acute cocaine toxicity.

  1. Pentobarbital Toxicity after Self-Administration of Euthasol Veterinary Euthanasia Medication

    Directory of Open Access Journals (Sweden)

    Steven Jason Crellin

    2016-01-01

    Full Text Available Suicide attempt via sodium pentobarbital is uncommon. A 48-year-old woman with a history of depression and prior suicide attempt was found unresponsive by her veterinarian spouse near a syringe containing pink solution. Upon EMS’ arrival, the patient was experiencing apnea, hypoxemia, and miotic pupils; her blood glucose level measured 73 mg/dL. She was bradycardic and administered atropine with transient improvement in heart rate and transported to an emergency department; 2 mg of intravenous naloxone was administered without effect. She was endotracheally intubated via rapid sequence intubation. Rapid urine drug screening detected both benzodiazepines and barbiturates. The patient was transferred to an intensive care unit where she demonstrated a nearly absent radial pulse. Emergent fasciotomy to the left forearm and carpal tunnel was performed for acute compartment syndrome; “Euthasol” had been self-administered into the antecubital fossa. Expanded toxicological analysis via liquid chromatography/mass spectroscopy detected caffeine, atropine, 7-aminoclonazepam, phenytoin, citalopram, and naproxen. The patient’s coma resolved over 48 hours and she was successfully extubated without complication. Emergency physicians must closely monitor patients exposed to veterinary euthanasia agents who develop central nervous system and respiratory depression, hypothermia, bradycardia, hypotension, or skin injury. Consultation with a regional poison center and medical toxicologist is recommended.

  2. Adaptations in Basal and Hypothalamic–Pituitary–Adrenal-Activated Deoxycorticosterone Responses Following Ethanol Self-administration in Cynomolgus Monkeys

    Science.gov (United States)

    Jimenez, Vanessa A.; Porcu, Patrizia; Morrow, A. Leslie; Grant, Kathleen A.

    2017-01-01

    Acute ethanol activates the hypothalamic–pituitary–adrenal (HPA) axis, while long-term exposure results in a blunted neuroendocrine state, particularly with regards to the primary endpoint, cortisol, the primary glucocorticoid produced in the adrenal cortex. However, it is unknown if this dampened neuroendocrine status also influences other adrenocortical steroids. Plasma concentration of the mineralocorticoid and neuroactive steroid precursor deoxycorticosterone (DOC) is altered by pharmacological challenges of the HPA axis in cynomolgus monkeys. The present study investigated HPA axis regulation of circulating DOC concentration over the course of ethanol (4% w/v) induction and self-administration in non-human primates (Macaca fasciculata, n = 10). Plasma DOC, measured by radioimmunoassay, was compared at baseline (ethanol naïve), during schedule-induced polydipsia, and following 6-months of 22 h/day access to ethanol and water. The schedule induction of ethanol drinking did not alter basal DOC levels but selectively dampened the DOC response to pharmacological challenges aimed at the anterior pituitary (ovine corticotrophin-releasing hormone) and adrenal gland (post-dexamethasone adrenocorticotropin hormone), while pharmacological inhibition of central opioid receptors with naloxone greatly enhanced the DOC response during induction. Following 6 months of ethanol self-administration, basal DOC levels were increased more than twofold, while responses to each of the challenges normalized somewhat but remained significantly different than baseline. These data show that HPA axis modulation of the neuroactive steroid precursor DOC is markedly altered by the schedule induction of ethanol drinking and long-term voluntary ethanol self-administration. The consequences of chronic ethanol consumption on HPA axis regulation of DOC point toward allostatic modification of hypothalamic and adrenal function. PMID:28220108

  3. Tetrabenazine inhibition of monoamine uptake and methamphetamine behavioral effects: locomotor activity, drug discrimination and self-administration.

    Science.gov (United States)

    Meyer, A C; Horton, D B; Neugebauer, N M; Wooters, T E; Nickell, J R; Dwoskin, L P; Bardo, M T

    2011-09-01

    Tetrabenazine (TBZ), a benzoquinolizine derivative, binds with high affinity to the vesicular monoamine transporter-2 (VMAT2), inhibiting uptake of cytosolic monoamines. The current study aimed to provide preclinical evidence supporting the potential use of TBZ as a treatment for methamphetamine abuse. Effects of TBZ on function of the dopamine transporter (DAT) and serotonin transporter (SERT) in striatal and hippocampal synaptosomes, respectively, and on VMAT2 function in isolated striatal synaptic vesicles were determined. Effect of TBZ (acute, 0.1-3.0 mg/kg, s.c.; repeated, 1.0 mg/kg for 7 days) on locomotor activity in methamphetamine-sensitized rats was assessed. Ability of TBZ (0.1-3.0 mg/kg; s.c.) or vehicle to decrease the discriminative effect of methamphetamine also was determined. Ability of TBZ (acute, 0.1-1.0 mg/kg, s.c.; repeated, 0.1 or 1.0 mg/kg for 7 days) to specifically decrease methamphetamine self-administration was determined; for comparison, a separate group of rats was assessed for effects of TBZ on food-maintained responding. Results show that TBZ was 11-fold more potent inhibiting DAT than SERT, and 2.5-fold more potent inhibiting VMAT2 than DAT. Results from behavioral studies showed that the lowest dose of TBZ transiently increased methamphetamine self-administration, whereas higher TBZ doses decreased methamphetamine self-administration. Also, TBZ at high doses decreased methamphetamine locomotor sensitization and discriminative stimulus effects, as well as food-maintained responding. Thus, despite acting as a potent VMAT2 inhibitor, these preclinical results indicate that TBZ lacks behavioral specificity as an inhibitor of methamphetamine-induced reinforcement, diminishing its viability as a suitable treatment for methamphetamine abuse.

  4. Tetrabenazine inhibition of monoamine uptake and methamphetamine behavioral effects: Locomotor activity, drug discrimination and self-administration

    Science.gov (United States)

    Meyer, AC; Horton, DB; Neugebauer, NM; Wooters, TE; Nickell, JR; Dwoskin, LP; Bardo, MT

    2013-01-01

    Tetrabenazine (TBZ), a benzoquinolizine derivative, binds with high affinity to the vesicular monoamine transporter-2 (VMAT2), inhibiting uptake of cytosolic monoamines. The current study aimed to provide preclinical evidence supporting the potential use of TBZ as a treatment for methamphetamine abuse. Effects of TBZ on function of the dopamine transporter (DAT) and serotonin transporter (SERT) in striatal and hippocampal synaptosomes, respectively, and on VMAT2 function in isolated striatal synaptic vesicles were determined. Effect of TBZ (acute, 0.1 - 3.0 mg/kg, s.c.; repeated, 1.0 mg/kg for 7 days) on locomotor activity in methamphetamine-sensitized rats was assessed. Ability of TBZ (0.1 -3.0 mg/kg; s.c.) or vehicle to decrease the discriminative effect of methamphetamine also was determined. Ability of TBZ (acute, 0.1 - 1.0 mg/kg, s.c.; repeated, 0.1 or 1.0 mg/kg for 7 days) to specifically decrease methamphetamine self-administration was determined; for comparison, a separate group of rats was assessed for effects of TBZ on food-maintained responding. Results show that TBZ was 11-fold more potent inhibiting DAT than SERT, and 2.5-fold more potent inhibiting VMAT2 than DAT. Results from behavioral studies showed that the lowest dose of TBZ transiently increased methamphetamine self-administration, whereas higher TBZ doses decreased methamphetamine self-administration. Also, TBZ at high doses decreased methamphetamine locomotor sensitization and discriminative stimulus effects, as well as food-maintained responding. Thus, despite acting as a potent VMAT2 inhibitor, these preclinical results indicate that TBZ lacks behavioral specificity as an inhibitor of methamphetamine-induced reinforcement, diminishing its viability as a suitable treatment for methamphetamine abuse. PMID:21669212

  5. R(+-baclofen, but not S(--baclofen, alters alcohol self-administration in alcohol-preferring rats

    Directory of Open Access Journals (Sweden)

    Irene eLorrai

    2016-04-01

    Full Text Available Racemic baclofen [(±-baclofen] has repeatedly been reported to suppress several alcohol-motivated behaviors, including alcohol drinking and alcohol self-administration, in rats and mice. Recent data suggested that baclofen may have bidirectional, stereospecific effects, with the more active enantiomer, R(+-baclofen, suppressing alcohol intake and the less active enantiomer, S(--baclofen, stimulating alcohol intake in mice. The present study was designed to investigate whether this enantioselectivity of baclofen effects may extend also to the reinforcing properties of alcohol in rats. To this end, selectively bred Sardinian alcohol-preferring (sP rats were initially trained to lever-respond on a Fixed Ratio (FR 4 (FR4 schedule of reinforcement for alcohol (15%, v/v in daily 30-min sessions. Once responding had stabilized, rats were tested with vehicle, (±-baclofen (3 mg/kg, R(+-baclofen (0.75, 1.5, and 3 mg/kg, and S(--baclofen (6, 12, and 24 mg/kg under the FR4 schedule of reinforcement. Treatment with 3 mg/kg (±-baclofen reduced the number of lever-responses for alcohol and estimated amount of self-administered alcohol by approximately 60% in comparison to vehicle treatment. R(+-baclofen was approximately twice as active as (±-baclofen: treatment with 1.5 mg/kg R(+-baclofen decreased both variables to an extent similar to that of the decreasing effect of 3 mg/kg (±-baclofen. Conversely, treatment with all doses of S(--baclofen failed to affect alcohol self-administration. These results (a confirm that non-sedative doses of (±-baclofen effectively suppressed the reinforcing properties of alcohol in sP rats and (b apparently do not extend to operant alcohol self-administration in sP rats the capability of S(--baclofen to stimulate alcohol drinking in mice.

  6. Binge-like acquisition of 3,4-methylenedioxypyrovalerone (MDPV) self-administration and wheel activity in rats.

    Science.gov (United States)

    Aarde, S M; Huang, P K; Dickerson, T J; Taffe, M A

    2015-06-01

    Lack of access to conventional sources of reinforcement has been proposed as a risk factor for substance abuse in lower socioeconomic populations. There is laboratory evidence that behavioral alternatives (enrichment or exercise) and alternative reinforcers (e.g., sweetened solutions) can reduce self-administration of a variety of drugs. The objective of this study is to determine if drug self-administration could devalue wheel activity in an animal model. Male Wistar rats were trained to self-administer 3,4-methylenedioxypyrovalerone (MDPV; "bath salts"), 0.05 mg/kg/infusion, i.v., with concurrent access to a running wheel that was either locked (LW) or unlocked (UW). MDPV intake steadily increased across the 20-session acquisition interval but did not differ significantly between UW and LW groups. Mean wheel rotations declined significantly across the acquisition interval in the UW group. Of the rats that acquired self-administration, 60 % engaged in a binge-like behavior at the initiation of acquisition; intake was limited only by post-reinforcement time-out. The binge rats had higher post-acquisition levels of drug intake (even after excluding the binge session), and the UW binge rats showed a precipitous post-acquisition drop in wheel activity that was not observed in the UW no-binge rats. These data confirm that MDPV is a powerful reward/reinforcer and show that a relatively high rate of intake at the onset of drug taking can devalue natural rewards (wheel activity) and can predict higher subsequent drug intake levels. Thus, limiting the intensity of initial drug exposure may attenuate subsequent drug abuse/addiction by preventing the devaluation of natural alternative rewards/reinforcers.

  7. Bacterial cocaine esterase: a protein-based therapy for cocaine overdose and addiction.

    Science.gov (United States)

    Narasimhan, Diwahar; Woods, James H; Sunahara, Roger K

    2012-02-01

    Cocaine is highly addictive and there are no pharmacotherapeutic drugs available to treat acute cocaine toxicity or chronic abuse. Antagonizing an inhibitor such as cocaine using a small molecule has proven difficult. The alternative approach is to modify cocaine's pharmacokinetic properties by sequestering or hydrolyzing it in serum and limiting access to its sites of action. We took advantage of a bacterial esterase (CocE) that has evolved to hydrolyze cocaine and have developed it as a therapeutic that rapidly and specifically clears cocaine from the subject. Native enzyme was unstable at 37°C, thus limiting CocE's potential. Innovative computational methods based on the protein's structure helped elucidate its mechanism of destabilization. Novel protein engineering methodologies were applied to substantially improve its stability in vitro and in vivo. These improvements rendered CocE as a powerful and efficacious therapeutic to treat cocaine intoxication and lead the way towards developing a therapy for addiction.

  8. Pain management in emergency department: intravenous morphine vs. intravenous acetaminophen

    Directory of Open Access Journals (Sweden)

    Morteza Talebi Doluee

    2015-01-01

    Full Text Available Pain is the most common complaint in emergency department and there are several methods for its control. Among them, pharmaceutical methods are the most effective. Although intravenous morphine has been the most common choice for several years, it has some adverse effects. There are many researches about intravenous acetaminophen as an analgesic agent and it appears that it has good analgesic effects for various types of pain. We searched some electronic resources for clinical trials comparing analgesic effects of intravenous acetaminophen vs. intravenous morphine for acute pain treatment in emergency setting.In two clinical trials, the analgesic effect of intravenous acetaminophen has been compared with intravenous morphine for renal colic. The results revealed no significant difference between analgesic effects of two medications. Another clinical trial revealed that intravenous acetaminophen has acceptable analgesic effects on the post-cesarean section pain when combined with other analgesic medications. One study revealed that administration of intravenous acetaminophen compared to placebo before hysterectomy decreased consumption of morphine via patient-controlled analgesia pump and decreased the side effects. Similarly, another study revealed that the infusion of intravenous acetaminophen vs. placebo after orthopedic surgery decreased the consumption of morphine after the surgery. A clinical trial revealed intravenous acetaminophen provided a level of analgesia comparable to intravenous morphine in isolated limb trauma, while causing less side effects than morphine.It appears that intravenous acetaminophen has good analgesic effects for visceral, traumatic and postoperative pains compare with intravenous morphine.

  9. Activation of mGluR7s inhibits cocaine-induced reinstatement of drug-seeking behavior by a nucleus accumbens glutamate-mGluR2/3 mechanism in rats.

    Science.gov (United States)

    Li, Xia; Li, Jie; Gardner, Eliot L; Xi, Zheng-Xiong

    2010-09-01

    The metabotropic glutamate receptor 7 (mGluR7) has been reported to be involved in cocaine and alcohol self-administration. However, the role of mGluR7 in relapse to drug seeking is unknown. Using a rat relapse model, we found that systemic administration of AMN082, a selective mGluR7 allosteric agonist, dose-dependently inhibits cocaine-induced reinstatement of drug-seeking behavior. Intracranial microinjections of AMN082 into the nucleus accumbens (NAc) or ventral pallidum, but not the dorsal striatum, also inhibited cocaine-primed reinstatement, an effect that was blocked by local co-administration of MMPIP, a selective mGluR7 antagonist. In vivo microdialysis demonstrated that cocaine priming significantly increased extracellular dopamine in the NAc, ventral pallidum and dorsal striatum, while increasing extracellular glutamate in the NAc only. AMN082 alone failed to alter extracellular dopamine, but produced a slow-onset long-lasting increase in extracellular glutamate in the NAc only. Pre-treatment with AMN082 dose-dependently blocked both cocaine-enhanced NAc glutamate and cocaine-induced reinstatement, an effect that was blocked by MMPIP or LY341497 (a selective mGluR2/3 antagonist). These data suggest that mGluR7 activation inhibits cocaine-induced reinstatement of drug-seeking behavior by a glutamate-mGluR2/3 mechanism in the NAc. The present findings support the potential use of mGluR7 agonists for the treatment of cocaine addiction.

  10. Hierarchical recruitment of phasic dopamine signaling in the striatum during the progression of cocaine use.

    Science.gov (United States)

    Willuhn, Ingo; Burgeno, Lauren M; Everitt, Barry J; Phillips, Paul E M

    2012-12-11

    Drug addiction is a neuropsychiatric disorder that marks the end stage of a progression beginning with recreational drug taking but culminating in habitual and compulsive drug use. This progression is considered to reflect transitions among multiple neural loci. Dopamine neurotransmission in the ventromedial striatum (VMS) is pivotal in the control of initial drug use, but emerging evidence indicates that once drug use is well established, its control is dominated by the dorsolateral striatum (DLS). In the current work, we conducted longitudinal neurochemical recordings to ascertain the spatiotemporal profile of striatal dopamine release and to investigate how it changes during the period from initial to established drug use. Dopamine release was detected using fast-scan cyclic voltammetry simultaneously in the VMS and DLS of rats bearing indwelling i.v. catheters over the course of 3 wk of cocaine self-administration. We found that phasic dopamine release in DLS emerged progressively during drug taking over the course of weeks, a period during which VMS dopamine signaling declined. This emergent dopamine signaling in the DLS mediated discriminated behavior to obtain drug but did not promote escalated or compulsive drug use. We also demonstrate that this recruitment of dopamine signaling in the DLS is dependent on antecedent activity in VMS circuitry. Thus, the current findings identify a striatal hierarchy that is instantiated during the expression of established responses to obtain cocaine.

  11. Opiate and Cocaine Exposed Newborns: Growth Outcomes.

    Science.gov (United States)

    Butz, Arlene M.; Kaufmann, Walter E.; Royall, Richard; Kolodner, Ken; Pulsifer, Margaret B.; Lears, Mary Kathleen; Henderson, Robin; Belcher, Harolyn; Sellers, Sherri; Wilson, Modena

    1999-01-01

    Examines growth parameters at birth in 204 infants born to mothers who used cocaine and/or opiates during pregnancy. Outcome measures included birth weight, length, and head circumference. Study provides support that in utero cocaine exposure may confer more risk for somatic growth retardation at birth than opiate exposure. (Author/GCP)

  12. Levamisole-contaminated cocaine : a hairy affair

    NARCIS (Netherlands)

    van der Veer, Tjeerd; Pennings, Ed; Tervaert, J W Cohen; Korswagen, Lindy-Anne

    2015-01-01

    Levamisole-contaminated cocaine can induce severe systemic vasculitis. The diagnosis can be challenging, especially when substance abuse is uncertain. We present the case of a 42-year-old woman suffering from vasculitis due to levamisole-contaminated cocaine, who persistently denied substance abuse.

  13. Cilioretinal artery occlusion following intranasal cocaine insufflations

    Directory of Open Access Journals (Sweden)

    Balaji Kannan

    2011-01-01

    Full Text Available Cocaine is used to produce a euphoric effect by abusers, who may be unaware of the devastating systemic and ocular side effects of this drug. We describe the first known case of cilioretinal artery occlusion after intranasal cocaine abuse.

  14. Osteonecrosis following alcohol, cocaine, and steroid use.

    LENUS (Irish Health Repository)

    Ziraldo, Laura

    2012-02-01

    Alcohol, steroids and cocaine have all been shown to be independent risk factors for osteonecrosis when taken in excess. Here we present a case of a young girl who developed debilitating osteonecrosis secondary to low doses of alcohol, steroids and cocaine. We feel it is important to highlight to those caring for such patients of the potential devastating complication of these three agents.

  15. A Simple Economic Model of Cocaine Production

    Science.gov (United States)

    1994-01-01

    the production dhain that are vulnerable to itr o as well as providing a clearer picture of the path that cocaine takes before reading retail markts in...In fact, given the volatility of cocaine product prices in PBC, it is probably not uncommon for segments of production to be unprofitable at times

  16. Signs of Cocaine Abuse and Addiction

    Science.gov (United States)

    ... Use and Addiction Signs of Cocaine Use and Addiction Listen ©istock.com/ AntonioGuillern After the "high" of the cocaine wears off, you can "crash" and feel tired and sad for days. You also get a strong craving to take the drug again to try to ...

  17. Chronic cocaine-induced H3 acetylation and transcriptional activation of CaMKIIalpha in the nucleus accumbens is critical for motivation for drug reinforcement.

    Science.gov (United States)

    Wang, Lei; Lv, Zhigang; Hu, Zhaoyang; Sheng, Jian; Hui, Bin; Sun, Jie; Ma, Lan

    2010-03-01

    The regulation of gene expression in the brain reward regions is known to contribute to the pathogenesis and persistence of drug addiction. Increasing evidence suggests that the regulation of gene transcription is mediated by epigenetic mechanisms that alter the chromatin structure at specific gene promoters. To better understand the involvement of epigenetic regulation in drug reinforcement properties, rats were subjected to cocaine self-administration paradigm. Daily histone deacetylase (HDAC) inhibitor infusions in the shell of the nucleus accumbens (NAc) caused an upward shift in the dose-response curve under fixed-ratio schedule and increased the break point under progressive-ratio schedule, indicating enhanced motivation for self-administered drug. The effect of the HDAC inhibitor is attributed to the increased elevation of histone acetylation induced by chronic, but not acute, cocaine experience. In contrast, neutralizing the chronic cocaine-induced increase in histone modification by the bilateral overexpression of HDAC4 in the NAc shell reduced drug motivation. The association between the motivation for cocaine and the transcriptional activation of addiction-related genes by H3 acetylation in the NAc shell was analyzed. Among the genes activated by chronic cocaine experiences, the expression of CaMKIIalpha, but not CaMKIIbeta, correlated positively with motivation for the drug. Lentivirus-mediated shRNA knockdown experiments showed that CaMKIIalpha, but not CaMKIIbeta, in the NAc shell is essential for the maintenance of motivation to self-administered cocaine. These findings suggest that chronic drug-use-induced transcriptional activation of genes, such as CaMKIIalpha, modulated by H3 acetylation in the NAc is a critical regulatory mechanism underlying motivation for drug reinforcement.

  18. Noribogaine, but not 18-MC, exhibits similar actions as ibogaine on GDNF expression and ethanol self-administration.

    Science.gov (United States)

    Carnicella, Sebastien; He, Dao-Yao; Yowell, Quinn V; Glick, Stanley D; Ron, Dorit

    2010-10-01

    Ibogaine is a naturally occurring alkaloid that has been reported to decrease various adverse phenotypes associated with exposure to drugs of abuse and alcohol in human and rodent models. Unfortunately, ibogaine cannot be used as a medication to treat addiction because of severe side effects. Previously, we reported that the desirable actions of ibogaine to reduce self-administration of, and relapse to, alcohol consumption are mediated via the upregulation of the expression of the glial cell line-derived neurotrophic factor (GDNF) in the midbrain ventral tegmental area (VTA), and the consequent activation of the GDNF pathway. The ibogaine metabolite, noribogaine, and a synthetic derivative of ibogaine, 18-Methoxycoronaridine (18-MC), possess a similar anti-addictive profile as ibogaine in rodent models, but without some of its adverse side effects. Here, we determined whether noribogaine and/or 18-MC, like ibogaine, increase GDNF expression, and whether their site of action to reduce alcohol consumption is the VTA. We used SH-SY5Y cells as a cell culture model and found that noribogaine, like ibogaine, but not 18-MC, induces a robust increase in GDNF mRNA levels. Next, we tested the effect of intra-VTA infusion of noribogaine and 18-MC on rat operant alcohol self-administration and found that noribogaine, but not 18-MC, in the VTA decreases responding for alcohol. Together, our results suggest that noribogaine and 18-MC have different mechanisms and sites of action.

  19. Dopamine D3 Receptor Antagonist (GSK598809) Potentiates the Hypertensive Effects of Cocaine in Conscious, Freely-Moving Dogs.

    Science.gov (United States)

    Appel, Nathan M; Li, Shou-Hua; Holmes, Tyson H; Acri, Jane B

    2015-09-01

    The chronic and relapsing nature of addiction presents unique challenges for ensuring the safety of a potential medication. A patient may use cocaine, for example, while taking the medication or take more medication than prescribed. Thus, a potential medication must be safe and not exacerbate the effects of cocaine. Multiple published studies support antagonism of brain dopamine D3 receptor function as a potential mechanism of action for an anti-addiction medication. Dopamine D3 receptors are widely distributed outside the central nervous system, however; for example, dopamine D3 receptors in the kidneys are implicated in regulating blood pressure. The selective dopamine D3 receptor antagonist GSK598809 [1-(2-fluoro-4-trifluoromethyl-phenyl)-3-{3-[4-methyl-5-(4-methyl-oxazol-5-yl)-4H-[1,2,4]triazol-3-ylsulfanyl]-propyl}-3-aza-bicyclo[3.1.0]hexane] has been proposed as a medication to treat cocaine and other substance use disorders. The US Food and Drug Administration has established guidelines recommending safety studies to investigate potential undesirable pharmacodynamic effects of a substance in relation to exposure in the therapeutic range and above. Hence, we assessed the interaction between this selective dopamine D3 receptor antagonist and cocaine on hemodynamics and cardiac function in freely-moving, telemetered dogs before conducting a clinical trial. GSK598809 increased the hemodynamic effect of cocaine in this model. Thus, the increase in blood pressure after intravenous cocaine was greater in animals that had been pretreated with GSK598809 compared with vehicle. This finding suggests that GSK598809 in particular, and perhaps dopamine D3 receptor antagonists as a class, may produce unacceptable cardiovascular risks as medications to treat cocaine use disorder.

  20. Levamisole and cocaine synergism: a prevalent adulterant enhances cocaine's action in vivo.

    Science.gov (United States)

    Tallarida, Christopher S; Egan, Erin; Alejo, Gissel D; Raffa, Robert; Tallarida, Ronald J; Rawls, Scott M

    2014-04-01

    Levamisole is estimated by the Drug Enforcement Agency (DEA) to be present in about 80% of cocaine seized in the United States and linked to debilitating, and sometimes fatal, immunologic effects in cocaine abusers. One explanation for the addition of levamisole to cocaine is that it increases the amount of product and enhances profits. An alternative possibility, and one investigated here, is that levamisole alters cocaine's action in vivo. We specifically investigated effects of levamisole on cocaine's stereotypical and place-conditioning effects in an established invertebrate (planarian) assay. Acute exposure to levamisole or cocaine produced concentration-dependent increases in stereotyped movements. For combined administration of the two agents, isobolographic analysis revealed that the observed stereotypical response was enhanced relative to the predicted effect, indicating synergism for the interaction. In conditioned place preference (CPP) experiments, cocaine produced a significant preference shift; in contrast, levamisole was ineffective at all concentrations tested. For combination experiments, a submaximal concentration of cocaine produced CPP that was enhanced by inactive concentrations of levamisole, indicating synergism. The present results provide the first experimental evidence that levamisole enhances cocaine's action in vivo. Most important is the identification of synergism for the levamisole/cocaine interaction, which now requires further study in mammals.

  1. Levamisole and cocaine synergism: a prevalent adulterant enhances cocaine's action in vivo

    Science.gov (United States)

    Tallarida, Christopher S.; Egan, Erin; Alejo, Gissel D.; Raffa, Robert; Tallarida, Ronald J.; Rawls, Scott M.

    2014-01-01

    Levamisole is estimated by the Drug Enforcement Agency (DEA) to be present in about 80% of cocaine seized in the United States and linked to debilitating, and sometimes fatal, immunologic effects in cocaine abusers. One explanation for the addition of levamisole to cocaine is that it increases the amount of product and enhances profits. An alternative possibility, and one investigated here, is that levamisole alters cocaine's action in vivo. We specifically investigated effects of levamisole on cocaine's stereotypical and place-conditioning effects in an established invertebrate (planarian) assay. Acute exposure to levamisole or cocaine produced concentration-dependent increases in stereotyped movements. For combined administration of the two agents, isobolographic analysis revealed that the observed stereotypical response was enhanced relative to the predicted effect, indicating synergism for the interaction. In conditioned place preference (CPP) experiments, cocaine produced a significant preference shift; in contrast, levamisole was ineffective at all concentrations tested. For combination experiments, a submaximal concentration of cocaine produced CPP that was enhanced by inactive concentrations of levamisole, indicating synergism. The present results provide the first experimental evidence that levamisole enhances cocaine's action in vivo. Most important is the identification of synergism for the levamisole/cocaine interaction, which now requires further study in mammals. PMID:24440755

  2. Anorexic activity of cocaine and coca extract in naive and cocaine tolerant rats.

    Science.gov (United States)

    Vee, G L; Fink, G B; Constantine, G H

    1983-04-01

    Dose response curves for reducing limited access food consumption were determined for cocaine HCl IP, cocaine HCl PO, and whole Erythroxylum coca extract PO. The ED50's for cocaine HCl in drug naive rats were 19.6 mg/kg (IP) and 34.6 mg/kg (PO). When the dose of E. coca extract was expressed in terms of cocaine HCl content, the ED50 was 52.6 mg/kg (PO). When dose response curves were determined in rats that had received cocaine (45 mg/kg, PO) for 30 days, a shift to the right in the cocaine HCl curve (an ED50 of 98.4 mg/kg PO) indicated tolerance. However, the shift to the right was less for E. coca extract than for cocaine HCl. Although the anorexic activity of E. coca extract was less than that of an equivalent amount of cocaine in naive rats it was often more than that of equivalent doses of cocaine HCl in tolerant rats. Interaction with other constituents of E. coca extract appears to alter the potency of the cocaine content of the extract in different directions in naive and tolerant rats.

  3. Personality traits of cocaine-dependent patients associated with cocaine-positive baseline urine at hospitalization.

    Science.gov (United States)

    de Los Cobos, José Pérez; Siñol, Núria; Bañulus, Enrique; Batlle, Francisca; Tejero, Antoni; Trujols, Joan

    2010-01-01

    Cocaine abstinence at treatment entry is considered a predictor of good response in cocaine dependence treatment. Therefore, identification of factors facilitating pretreatment cocaine abstinence could be useful for developing new therapeutic strategies. This retrospective chart review study examines the association between personality traits and cocaine-positive baseline urinalysis (CPB) in cocaine-dependent inpatients. All 107 participants met DSM-IV criteria for cocaine dependence, and were admitted consecutively to a closed addiction unit for detoxification treatment. Personality was assessed with the Temperament and Character Inventory and the Millon Clinical Multiaxial Inventory (MCMI-II). CPB was detected in 80 patients (74.8%). The logistic regression model solely based on personality dimensions showed that only the MCMI-II avoidant traits were significantly associated with a decreased probability of cocaine-dependent patients presenting CPB. The logistic regression model based on both personality dimensions and substance use-related variables alike retained the number of days of cocaine use during the last 30 days as a risk factor, and alcohol dependence and the MCMI-II schizoid dimension as protective factors in predicting CPB results. Avoidant and schizoid traits are personality dimensions of cocaine-dependent patients that are associated with cocaine abstinence prior to inpatient admission. These findings suggest an inverse relationship between social isolation and CPB. Notwithstanding, more research is needed, not only to assess the generalizability of these findings, but also to enrich the personality and substance use model with variables related to readiness to change.

  4. Dopamine transporter inhibition is required for cocaine-induced stereotypy

    OpenAIRE

    Tilley, Michael R.; Gu, Howard H.

    2008-01-01

    The primary mechanism by which cocaine induces stereotypy has been difficult to discern because cocaine has three high affinity targets, the reuptake transporters for dopamine (DAT), norepinephrine, and serotonin. To dissect out the role of DAT in cocaine effects, we generated a knock-in mouse line with a cocaine insensitive DAT (DAT-CI mice). DAT-CI mice provide a powerful tool that can directly test whether DAT inhibition is important for cocaine-induced stereotypy. We found that acute coca...

  5. In vivo potency and efficacy of the novel cathinone α-pyrrolidinopentiophenone and 3,4-methylenedioxypyrovalerone: Self-administration and locomotor stimulation in male rats

    Science.gov (United States)

    Aarde, Shawn M.; Creehan, Kevin M.; Vandewater, Sophia A.; Dickerson, Tobin J.; Taffe, Michael A.

    2015-01-01

    Rationale Numerous substituted cathinone drugs have appeared in recreational use. This variety is often a response to legal actions; the scheduling of 3,4-methylenedioxypyrovalerone (MDPV; “bath salts”) in the U.S.A. was followed by the appearance of the closely related drug α-pyrrolidinopentiophenone (alpha-PVP; “flakka”). Objectives To directly compare the efficacy and potency of alpha-PVP with that of MDPV. Methods Groups of male Wistar rats were trained in the intravenous self-administration (IVSA) alpha-PVP or MDPV under a fixed-ratio 1 schedule of reinforcement. An additional group was examined for locomotor and body temperature responses to non-contingent administration of MDVP or alpha-PVP (1.0, 5.6, 10.0 mg/kg, i.p.). Results Acquisition of alpha-PVP (0.1 mg/kg/infusion) IVSA resulted in low, yet consistent drug intake and excellent discrimination for the drug-paired lever. Dose-substitution (0.05-0.25 mg/kg/infusion) under a fixed-ratio 1 schedule confirmed potency is similar to MDPV in prior studies. In direct comparison to MDPV (0.05 mg/kg/infusion), rats trained on alpha-PVP (0.05 mg/kg/infusion) responded for more infusions but demonstrated similar drug-lever discrimination by the end of acquisition. However, the dose-response (0.018-0.56 mg/kg/inf) functions of these drugs under a progressive-ratio schedule of reinforcement reflected identical efficacy and potency. Peak locomotor responses to MDPV or alpha-PVP were observed after the 1.0 mg/kg, i.p. dose and lasted ~2 hours. Modest body temperature decreases were of similar magnitude (~0.75°C) for each compound. Conclusions The potency and efficacy of MDPV and alpha-PVP were very similar across multiple assays, predicting that the abuse liability of alpha-PVP will be significant and similar to that of MDPV. PMID:25925780

  6. In vivo potency and efficacy of the novel cathinone α-pyrrolidinopentiophenone and 3,4-methylenedioxypyrovalerone: self-administration and locomotor stimulation in male rats.

    Science.gov (United States)

    Aarde, Shawn M; Creehan, Kevin M; Vandewater, Sophia A; Dickerson, Tobin J; Taffe, Michael A

    2015-08-01

    Numerous substituted cathinone drugs have appeared in recreational use. This variety is often a response to legal actions; the scheduling of 3,4-methylenedioxypyrovalerone (MDPV; "bath salts") in the USA was followed by the appearance of the closely related drug α-pyrrolidinopentiophenone (alpha-PVP; "flakka"). This study aimed to directly compare the efficacy and potency of alpha-PVP with that of MDPV. Groups of male Wistar rats were trained in the intravenous self-administration (IVSA) alpha-PVP or MDPV under a fixed-ratio 1 schedule of reinforcement. An additional group was examined for locomotor and body temperature responses to noncontingent administration of MDVP or alpha-PVP (1.0, 5.6, and 10.0 mg/kg, i.p.). Acquisition of alpha-PVP (0.1 mg/kg/infusion) IVSA resulted in low, yet consistent drug intake and excellent discrimination for the drug-paired lever. Dose substitution (0.05-0.25 mg/kg/infusion) under a fixed-ratio 1 schedule confirmed potency was similar to MDPV in prior studies. In direct comparison to MDPV (0.05 mg/kg/infusion), rats trained on alpha-PVP (0.05 mg/kg/infusion) responded for more infusions but demonstrated similar drug-lever discrimination by the end of acquisition. However, the dose-response (0.018-0.56 mg/kg/infusion) functions of these drugs under a progressive-ratio schedule of reinforcement reflected identical efficacy and potency. Peak locomotor responses to MDPV or alpha-PVP were observed after the 1.0 mg/kg, i.p. dose and lasted ∼2 h. Modest body temperature decreases were of similar magnitude (∼0.75 °C) for each compound. The potency and efficacy of MDPV and alpha-PVP were very similar across multiple assays, predicting that the abuse liability of alpha-PVP will be significant and similar to that of MDPV.

  7. Synthesis and structure-activity relationships of 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]pyridine analogues as potent, noncompetitive metabotropic glutamate receptor subtype 5 antagonists; search for cocaine medications.

    Science.gov (United States)

    Iso, Yasuyoshi; Grajkowska, Ewa; Wroblewski, Jarda T; Davis, Jared; Goeders, Nicholas E; Johnson, Kenneth M; Sanker, Subramaniam; Roth, Bryan L; Tueckmantel, Werner; Kozikowski, Alan P

    2006-02-09

    Recent genetic and pharmacological studies have suggested that the metabotropic glutamate receptor subtype 5 (mGluR5) may represent a druggable target in identifying new therapeutics for the treatment of various central nervous system disorders including drug abuse. In particular, considerable attention in the mGluR5 field has been devoted to identifying ligands that bind to the allosteric modulatory site, distinct from the site for the primary agonist glutamate. Both 2-methyl-6-(phenylethynyl)pyridine (MPEP) and its analogue 3-[(2-methyl-4-thiazolyl)ethynyl]pyridine (MTEP) have been shown to be selective and potent noncompetitive antagonists of mGluR5. Because of results presented in this study showing that MTEP prevents the reinstatement of cocaine self-administration caused by the presentation of environmental cues previously associated with cocaine availability, we have prepared a series of analogues of MTEP with the aim of gaining a better understanding of the structural features relevant to its antagonist potency and with the ultimate aim of investigating the effects of such compounds in blunting the self-administration of cocaine. These efforts have led to the identification of compounds showing higher potency as mGluR5 antagonists than either MPEP or MTEP. Two compounds 19 and 59 exhibited functional activity as mGluR5 antagonists that are 490 and 230 times, respectively, better than that of MTEP.

  8. [{sup 11}]Cocaine: PET studies of cocaine pharmacokinetics, dopamine transporter availability and dopamine transporter occupancy

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, Joanna S. E-mail: fowler@bnl.gov; Volkow, Nora D.; Wang, Gene-Jack; Gatley, S. John; Logan, Jean

    2001-07-01

    Cocaine was initially labeled with carbon-11 in order to track the distribution and pharmacokinetics of this powerful stimulant and drug of abuse in the human brain and body. It was soon discovered that [{sup 11}C]cocaine was not only useful for measuring cocaine pharmacokinetics and its relationship to behavior but that it is also a sensitive radiotracer for dopamine transporter (DAT) availability. Measures of DAT availability were facilitated by the development of a graphical analysis method (Logan Plot) for reversible systems which streamlined kinetic analysis. This expanded the applications of [{sup 11}C]cocaine to studies of DAT availability in the human brain and allowed the first comparative measures of the degree of DAT occupancy by cocaine and another stimulant drug methylphenidate. This article will summarize preclinical and clinical research with [{sup 11}C]cocaine.

  9. Modification by dopaminergic drugs of choice behavior under concurrent schedules of intravenous saline and food delivery in monkeys.

    Science.gov (United States)

    Gasior, Maciej; Paronis, Carol A; Bergman, Jack

    2004-01-01

    or two monkeys. These results agree with previous findings of similarity in the behavioral effects of cocaine and indirect or direct dopamine agonists and suggest, furthermore, that i.v. self-administration behavior engendered by priming doses of cocaine may involve actions mediated through both D1 and D2 families of dopamine receptors.

  10. Cocaine-associated lower limb ischemia.

    LENUS (Irish Health Repository)

    Collins, Chris G

    2011-07-25

    Cocaine-associated thrombosis has been reported in the literature with reports of vascular injuries to cardiac, pulmonary, intestinal, placental, and musculoskeletal vessels; however, injury of the pedal vessels is rare. We report on a 31-year-old man who presented 2 months following a cocaine binge with limb-threatening ischemia without an otherwise identifiable embolic source. Angiography confirmed extensive occlusive disease of the tibioperoneal vessels. The patient improved following therapy with heparin and a prostacyclin analogue. Cocaine-induced thrombosis should be considered in patients presenting with acute arterial insufficiency in the lower limb without any other identifiable cause.

  11. Mechanisms of Disulfiram-induced Cocaine Abstinence: Antabuse and Cocaine Relapse

    Science.gov (United States)

    Gaval-Cruz, Meriem; Weinshenker, David

    2009-01-01

    The anti-alcoholism drug disulfiram (Antabuse), which is an inhibitor of aldehyde dehydrogenase, induces an aversive reaction to alcohol consumption and thereby helps patients reduce alcohol intake. Recent clinical trials, initiated to investigate whether disulfiram could be used to treat individuals who abuse both alcohol and cocaine, have indicated that disulfiram effectively decreases cocaine consumption. Yet the ability of disulfiram to curb cocaine intake cannot be explained by the disruption of ethanol metabolism. Here, we synthesize clinical and animal data that point to dopamine β-hydroxylase inhibition as a mechanism underlying the efficacy of disulfiram in the treatment of cocaine dependence. PMID:19720750

  12. Mitochondrial complex I dysfunction induced by cocaine and cocaine plus morphine in brain and liver mitochondria.

    Science.gov (United States)

    Cunha-Oliveira, Teresa; Silva, Lisbeth; Silva, Ana Maria; Moreno, António J; Oliveira, Catarina R; Santos, Maria S

    2013-06-07

    Mitochondrial function and energy metabolism are affected in brains of human cocaine abusers. Cocaine is known to induce mitochondrial dysfunction in cardiac and hepatic tissues, but its effects on brain bioenergetics are less documented. Furthermore, the combination of cocaine and opioids (speedball) was also shown to induce mitochondrial dysfunction. In this work, we compared the effects of cocaine and/or morphine on the bioenergetics of isolated brain and liver mitochondria, to understand their specific effects in each tissue. Upon energization with complex I substrates, cocaine decreased state-3 respiration in brain (but not in liver) mitochondria and decreased uncoupled respiration and mitochondrial potential in both tissues, through a direct effect on complex I. Morphine presented only slight effects on brain and liver mitochondria, and the combination cocaine+morphine had similar effects to cocaine alone, except for a greater decrease in state-3 respiration. Brain and liver mitochondrial respirations were differentially affected, and liver mitochondria were more prone to proton leak caused by the drugs or their combination. This was possibly related with a different dependence on complex I in mitochondrial populations from these tissues. In summary, cocaine and cocaine+morphine induce mitochondrial complex I dysfunction in isolated brain and liver mitochondria, with specific effects in each tissue.

  13. Endogenous endophthalmitis associated with bacillus cereus bacteremia in a cocaine addict.

    Science.gov (United States)

    Masi, R J

    1978-10-01

    A 22-year-old black female intravenous cocaine addict presented with an endophthalmitis of the right eye. Diagnostic evaluation included an immediate anterior chamber paracentesis and a delayed vitreous aspiration. Although cultures from the involved eye were negative, all 7 blood cultures grew Bacillus cereus suggesting that this organism was the responsible agent of an endogenous endophthalmitis. The patient was treated with appropriate systemic and local antibiotics with resolution of the acute inflammatory signs. However, a phthisical eye has been noted on follow-up examinations.

  14. Alternative Splicing of AMPA subunits in Prefrontal Cortical Fields of Cynomolgus Monkeys following Chronic Ethanol Self-Administration

    Directory of Open Access Journals (Sweden)

    Glen eAcosta

    2012-01-01

    Full Text Available Functional impairment of the orbital and medial prefrontal cortex underlies deficits in executive control that characterize addictive disorders, including alcohol addiction. Previous studies indicate that alcohol alters glutamate neurotransmission and one substrate of these effects may be through the reconfiguration of the subunits constituting ionotropic glutamate receptor (iGluR complexes. Glutamatergic transmission is integral to cortico-cortical and cortico-subcortical communication and alcohol-induced changes in the abundance of the receptor subunits and/or their splice variants may result in critical functional impairments of prefrontal cortex in alcohol dependence. To this end, the effects of chronic ethanol self-administration on glutamate receptor ionotropic AMPA (GRIA subunit variant and kainate (GRIK subunit mRNA expression were studied in the orbitofrontal cortex (OFC, dorsolateral prefrontal cortex (DLPFC and anterior cingulate cortex (ACC of male cynomolgus monkeys. In DLPFC, total AMPA splice variant expression and total kainate receptor subunit expression were significantly decreased in alcohol drinking monkeys. Expression levels of GRIA3 flip and flop and GRIA4 flop mRNAs in this region were positively correlated with daily ethanol intake and blood ethanol concentrations averaged over the six months prior to necropsy. In OFC, AMPA subunit splice variant expression was reduced in the alcohol treated group. GRIA2 flop mRNA levels in this region were positively correlated with daily ethanol intake and blood ethanol concentrations averaged over the six months prior to necropsy. Results from these studies provide further evidence of transcriptional regulation of iGluR subunits in the primate brain following chronic alcohol self-administration. Additional studies examining the cellular localization of such effects in the framework of primate prefrontal cortical circuitry are warranted.

  15. Behavioral and neural substrates of habit formation in rats intravenously self-administering nicotine.

    Science.gov (United States)

    Clemens, Kelly J; Castino, Matthew R; Cornish, Jennifer L; Goodchild, Ann K; Holmes, Nathan M

    2014-10-01

    Tobacco addiction involves a transition from occasional, voluntary smoking towards habitual behavior that becomes increasingly resistant to quitting. The development of smoking habits may reflect a loss of behavioral control that can be modeled in rats. This study investigated the behavioral and neural substrates of habit formation in rats exposed to either brief (10 days) or extended (47 days) intravenous (IV) nicotine self-administration training. Following training, the first cohort of rats were exposed to a nicotine devaluation treatment, which involved repeated pairings of IV nicotine with lithium injection. They were then tested for sensitivity of responding to nicotine devaluation under extinction and reinstatement conditions. The second cohort of rats received equivalent self-administration training followed by processing of brain tissue for c-Fos immunohistochemistry. After brief training, devaluation suppressed nicotine-seeking during tests of extinction and reinstatement, confirming that responding is initially sensitive to current nicotine value, and therefore, goal directed. In contrast, after extended training, devaluation had no effect on extinction or reinstatement of responding, indicating that responding had become habitual. Complementary neuroanalysis revealed that extended nicotine self-administration was associated with increased c-Fos expression in brain regions implicated in habitual control of reward seeking, including activation of the dorsolateral striatum and substantia nigra pars compacta. These findings provide evidence of direct devaluation of an IV drug reward, that nicotine self-administration is initially goal-directed but becomes habitual with extended training, and that this behavioral transition involves activation of brain areas associated with the nigrostriatal system.

  16. Levamisole-contaminated cocaine: a hairy affair.

    Science.gov (United States)

    van der Veer, Tjeerd; Pennings, Ed; Tervaert, J W Cohen; Korswagen, Lindy-Anne

    2015-08-26

    Levamisole-contaminated cocaine can induce severe systemic vasculitis. The diagnosis can be challenging, especially when substance abuse is uncertain. We present the case of a 42-year-old woman suffering from vasculitis due to levamisole-contaminated cocaine, who persistently denied substance abuse. Symptoms included ulcerating skin lesions, arthralgia and myalgia, and the occurrence of an ileal intussusception. The definitive diagnosis was made using hair testing for toxins. She recovered through cocaine abstinence, but re-exposure resulted in a severe relapse with glomerulonephritis. Importantly, at time of the relapse, the patient became positive for both myeloperoxidase-antineutrophil cytoplasmic antibody (ANCA) and proteinase 3-ANCA. Cocaine-levamisole-induced vasculitis poses a great clinical challenge. The proper diagnostic strategy and therapy is still controversial. We highlight our diagnostic and therapeutic considerations, including hair testing for definitive proof of exposure.

  17. Impaired inhibitory control in recreational cocaine users.

    Directory of Open Access Journals (Sweden)

    Lorenza S Colzato

    Full Text Available Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed.

  18. A comparison of motivations for use among users of crack cocaine and cocaine powder in a sample of simultaneous cocaine and alcohol users.

    Science.gov (United States)

    Martin, Gina; Macdonald, Scott; Pakula, Basia; Roth, Eric A

    2014-03-01

    This study examined the motivations for using cocaine and alcohol comparing those who primarily smoked crack and those who primarily used cocaine powder when using simultaneously with alcohol. Motivations examined included: 1) to cope with a negative affect, 2) enhancement, 3) to be social and 4) to conform. The research design was a cross-sectional study in which clients in treatment for cocaine and alcohol problems completed a self-administered questionnaire about their substance use. Among those who primarily smoked crack or snorted cocaine when also using alcohol (n=153), there were 93 participants who reported primarily snorting cocaine and 60 participants who primarily reported smoking crack. Bivariate analyses found that those who primarily smoked crack reported lower social motivations to use alcohol and cocaine. When adjusting for other covariates in a multivariate analysis, social motivation was still significantly different between groups. Additionally, those who primarily smoked crack were more likely to be older, report higher cocaine dependence severity, be unemployed and were less likely to have completed some post-secondary education, than those who primarily snorted cocaine. No differences were found in enhancement, coping or conformity motivations between the two groups. These results suggest that simultaneous cocaine and alcohol use may have social importance to those who primarily snort cocaine, but that this importance is less evident to those who smoke crack. Consequently, future studies examining motivations for simultaneous cocaine and alcohol use should distinguish between different routes of cocaine administration.

  19. Methylphenidate attenuates limbic brain inhibition after cocaine-cues exposure in cocaine abusers.

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D.; Wang, G.; Volkow, N.D.; Wang, G.-J.; Tomasi, D.; Telang, F.; Fowler, J.S.; Pradhan, K.; Jayne, M.; Logan, J.; Goldstein, R.Z.; Alia-Klein, N.; Wong, C.T.

    2010-07-01

    Dopamine (phasic release) is implicated in conditioned responses. Imaging studies in cocaine abusers show decreases in striatal dopamine levels, which we hypothesize may enhance conditioned responses since tonic dopamine levels modulate phasic dopamine release. To test this we assessed the effects of increasing tonic dopamine levels (using oral methylphenidate) on brain activation induced by cocaine-cues in cocaine abusers. Brain metabolism (marker of brain function) was measured with PET and {sup 18}FDG in 24 active cocaine abusers tested four times; twice watching a Neutral video (nature scenes) and twice watching a Cocaine-cues video; each video was preceded once by placebo and once by methylphenidate (20 mg). The Cocaine-cues video increased craving to the same extent with placebo (68%) and with methylphenidate (64%). In contrast, SPM analysis of metabolic images revealed that differences between Neutral versus Cocaine-cues conditions were greater with placebo than methylphenidate; whereas with placebo the Cocaine-cues decreased metabolism (p<0.005) in left limbic regions (insula, orbitofrontal, accumbens) and right parahippocampus, with methylphenidate it only decreased in auditory and visual regions, which also occurred with placebo. Decreases in metabolism in these regions were not associated with craving; in contrast the voxel-wise SPM analysis identified significant correlations with craving in anterior orbitofrontal cortex (p<0.005), amygdala, striatum and middle insula (p<0.05). This suggests that methylphenidate's attenuation of brain reactivity to Cocaine-cues is distinct from that involved in craving. Cocaine-cues decreased metabolism in limbic regions (reflects activity over 30 minutes), which contrasts with activations reported by fMRI studies (reflects activity over 2-5 minutes) that may reflect long-lasting limbic inhibition following activation. Studies to evaluate the clinical significance of methylphenidate's blunting of cue

  20. Methylphenidate attenuates limbic brain inhibition after cocaine-cues exposure in cocaine abusers.

    Directory of Open Access Journals (Sweden)

    Nora D Volkow

    Full Text Available Dopamine (phasic release is implicated in conditioned responses. Imaging studies in cocaine abusers show decreases in striatal dopamine levels, which we hypothesize may enhance conditioned responses since tonic dopamine levels modulate phasic dopamine release. To test this we assessed the effects of increasing tonic dopamine levels (using oral methylphenidate on brain activation induced by cocaine-cues in cocaine abusers. Brain metabolism (marker of brain function was measured with PET and (18FDG in 24 active cocaine abusers tested four times; twice watching a Neutral video (nature scenes and twice watching a Cocaine-cues video; each video was preceded once by placebo and once by methylphenidate (20 mg. The Cocaine-cues video increased craving to the same extent with placebo (68% and with methylphenidate (64%. In contrast, SPM analysis of metabolic images revealed that differences between Neutral versus Cocaine-cues conditions were greater with placebo than methylphenidate; whereas with placebo the Cocaine-cues decreased metabolism (p<0.005 in left limbic regions (insula, orbitofrontal, accumbens and right parahippocampus, with methylphenidate it only decreased in auditory and visual regions, which also occurred with placebo. Decreases in metabolism in these regions were not associated with craving; in contrast the voxel-wise SPM analysis identified significant correlations with craving in anterior orbitofrontal cortex (p<0.005, amygdala, striatum and middle insula (p<0.05. This suggests that methylphenidate's attenuation of brain reactivity to Cocaine-cues is distinct from that involved in craving. Cocaine-cues decreased metabolism in limbic regions (reflects activity over 30 minutes, which contrasts with activations reported by fMRI studies (reflects activity over 2-5 minutes that may reflect long-lasting limbic inhibition following activation. Studies to evaluate the clinical significance of methylphenidate's blunting of cue-induced limbic

  1. The inhibition of cocaine-induced locomotor activity by CART 55-102 is lost after repeated cocaine administration.

    Science.gov (United States)

    Job, Martin O; Shen, Li L; Kuhar, Michael J

    2013-08-29

    CART peptide is known for having an inhibitory effect on cocaine- and dopamine-mediated actions after acute administration of cocaine and dopamine. In this regard, it is postulated to be a homeostatic, regulatory factor on dopaminergic activity in the nucleus accumbens (NAc). However, there is no data on the effect of CART peptide after chronic administration of cocaine, and this study addresses this. It was found that CART peptide blunted cocaine-induced locomotion (LMA) after acute administration of cocaine, as expected, but it did not affect cocaine-mediated LMA after chronic administration of cocaine. The loss of CART peptide's inhibitory effect did not return for up to 9 weeks after stopping the repeated cocaine administration. It may not be surprising that homeostatic regulatory mechanisms in the NAc are lost after repeated cocaine administration, and that this may be a mechanism in the development of addiction.

  2. Immunopharmacotherapeutic manifolds and modulation of cocaine overdose.

    Science.gov (United States)

    Treweek, Jennifer B; Roberts, Amanda J; Janda, Kim D

    2011-05-01

    Cocaine achieves its psychostimulant, reinforcing properties through selectively blocking dopamine transporters, and this neurobiological mechanism impedes the use of classical receptor-antagonist pharmacotherapies to outcompete cocaine at CNS sites. Passive immunization with monoclonal antibodies (mAb) specific for cocaine circumvents this problem as drug is sequestered in the periphery prior to entry into the brain. To optimize an immunopharmacotherapeutic strategy for reversing severe cocaine toxicity, the therapeutic properties of mAb GNC92H2 IgG were compared to those of its engineered formats in a mouse overdose model. Whereas the extended half-life of an IgG justifies its application to the prophylactic treatment of addiction, the rapid, thorough biodistribution of mAb-based fragments, including F(ab')₂, Fab and scFv, may correlate to accelerated scavenging of cocaine and reversal of toxicity. To test this hypothesis, mice were administered the anti-cocaine IgG (180 mg/kg, i.v.) or GNC92H2-based agent after receiving an LD₅₀ cocaine dose (93 mg/kg, i.p.), and the timeline of overdose symptoms was recorded. All formats lowered the rate of lethality despite the >100-fold molar excess of drug to antibody binding capacity. However, only F(ab')₂-92H2 and Fab-92 H2 significantly attenuated the progression of premorbid behaviors, and Fab-92H2 prevented seizure generation in a percentage of mice. The calculation of serum half-life of each format demonstrated that the pharmacokinetic profile of Fab-92H2 (elimination half-life, t½~100 min) best approximated that of cocaine. These results not only confirm the importance of highly specific and tight drug binding by the mAb, but also highlight the benefit of aligning the pharmacokinetic and pharmacodynamic properties of the immunopharmacotherapeutic with the targeted drug. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. CONSTRUCT THE MODEL OF METHAMPHETAMINE SELF-ADMINISTRATION IN RATS%大鼠甲基苯丙胺自身给药行为模型构建

    Institute of Scientific and Technical Information of China (English)

    孙艳; 马宝苗; 黄坤玉; 黄娴妮; 杨澍均; 刘昱

    2012-01-01

    目的:建立大鼠甲基苯丙胺自身给药行为模型.方法:训练♂SD大鼠通过鼻触行为进行甲基苯丙胺静脉自身给药,训练期剂量0.03 mg·kg-1或0.06 mg·kg-1.每天进行4 h.固定频率(FR)和渐变频率(PR)测试剂量为0.015、0.03、0.06、0.09和0.12 mg·kg-1)FR和PR测试分别为4 h和6 h.戒断停药2周后,大鼠重新返回实验笼进行消退及复吸测试,包括6个阶段的消退和一个阶段的复吸测试.结果:训练7 d后,80%的实验大鼠建立稳定的甲基苯丙胺静脉自身给药行为.FR剂量效应曲线是一条下降的曲线,即随着剂量的增加实验大鼠鼻触数降低.PR曲线是一条上升的曲线,即随着剂量的增加实验大鼠断点数逐渐增加.消退和复吸测试中主要测试有效鼻触数.经过6个阶段的消退测试,实验大鼠有效鼻触数下降到3±s 3次.随后经过一个阶段的复吸测试,大鼠有效鼻触数可上升至57±s 8次.结论:通过自身给药训练实验大鼠成功的获得了甲基苯丙胺的自身给药行为,消退和相关环境线索诱导的复吸模型.%Objective: To establish the model of methamphetamine self - administration in rats. Methods: Male SD rats were trained to intravenously self - administered methampheta - mine by nose -poking responding. The training doses were 0. 03 mg·kg or 0. 06 mg·kg-1. Subsequently, the animals self - administered methamphetamine(0. 015, 0. 03, 0. 06, 0. 09 and 0. 12 mg·kg -1)under the schedule of fixed ratio(FR) and progressive ratio( PR) . Each testing session of FR was 4 hours and PR, s was 6 hours. Following two - week abstinence, rats were returned to the testing chambers to test extinction and relapse responses. There were a total of 6 extinction sessions and a relapse session. Results: A total of 80% of rats exhibited stable responding of intravenous methamphetamine self - administration following seven days of training. The dose - response curve of FR and PR responding is downward and

  4. Suppressing effect of COR659 on alcohol, sucrose, and chocolate self-administration in rats: involvement of the GABAB and cannabinoid CB1 receptors.

    Science.gov (United States)

    Maccioni, Paola; Colombo, Giancarlo; Lorrai, Irene; Zaru, Alessandro; Carai, Mauro A M; Gessa, Gian Luigi; Brizzi, Antonella; Mugnaini, Claudia; Corelli, Federico

    2017-05-24

    COR659 [methyl2-(4-chlorophenylcarboxamido)-4-ethyl-5-methylthiophene-3-carboxylate] is a new, positive allosteric modulator (PAM) of the GABAB receptor. This study evaluated whether COR659 shared with previously tested GABAB PAMs the capacity to reduce alcohol self-administration in rats. Treatment with non-sedative doses of COR659 (2.5, 5, and 10 mg/kg; i.p.) suppressed lever-responding for alcohol (15% v/v) in Sardinian alcohol-preferring (sP) rats under the fixed ratio (FR) 4 (FR4) and progressive ratio (PR) schedules of reinforcement; COR659 was more potent and effective than the reference GABAB PAM, GS39783. Treatment with COR659, but not GS39783, suppressed (a) lever-responding for a sucrose solution (1-3% w/v) in sP rats under the FR4 and PR schedules, (b) lever-responding for a chocolate solution [5% (w/v) Nesquik®] in Wistar rats under the FR10 and PR schedules, and (c) cue-induced reinstatement of chocolate seeking in Wistar rats. Treatment with COR659 was completely ineffective on lever-responding (FR10) for regular food pellets in food-deprived Wistar rats. Pretreatment with the GABAB receptor antagonist, SCH50911, partially blocked COR659-induced reduction of alcohol self-administration, being ineffective on reduction of chocolate self-administration. Pretreatment with the cannabinoid CB1 receptor antagonist, AM4113, fully blocked COR659-induced reduction of chocolate self-administration, being ineffective on reduction of alcohol self-administration. COR659 might exert its behavioral effects via a composite mechanism: (i) positive allosteric modulation of the GABAB receptor, responsible for a large proportion of reduction of alcohol self-administration; (ii) an action at other receptor system(s), including the cannabinoid CB1 receptor, through which COR659 affects seeking and consumption of highly palatable foods.

  5. Vaccines against stimulants: cocaine and MA.

    Science.gov (United States)

    Kosten, Thomas; Domingo, Coreen; Orson, Frank; Kinsey, Berma

    2014-02-01

    While the worldwide prevalence of cocaine use remains significant, medications, or small molecule approaches, to treat drug addictions have met with limited success. Anti-addiction vaccines, on the other hand, have demonstrated great potential for treating drug abuse using a distinctly different mechanism of eliciting an antibody response that blocks the pharmacological effects of drugs. We provide a review of vaccine-based approaches to treating stimulant addictions; specifically and cocaine addictions. This selective review article focuses on the one cocaine vaccine that has been into clinical trials and presents new data related to pre-clinical development of a methamphetamine (MA) vaccine. We also review the mechanism of action for vaccine induced antibodies to abused drugs, which involves kinetic slowing of brain entry as well as simple blocking properties. We present pre-clinical innovations for MA vaccines including hapten design, linkage to carrier proteins and new adjuvants beyond alum. We provide some new information on hapten structures and linkers and variations in protein carriers. We consider a carrier, outer membrance polysaccharide coat protein (OMPC), that provides some self-adjuvant through lipopolysaccharide components and provide new results with a monophosopholipid adjuvant for the more standard carrier proteins with cocaine and MA. The review then covers the clinical trials with the cocaine vaccine TA-CD. The clinical prospects for advances in this field over the next few years include a multi-site cocaine vaccine clinical trial to be reported in 2013 and phase 1 clinical trials of a MA vaccine in 2014.

  6. Smoked cocaine in socially-depressed areas

    Directory of Open Access Journals (Sweden)

    Díaz Olga

    2010-11-01

    Full Text Available Abstract Background The main objectives of this study are to describe the smoked cocaine user's profile in socially-depressed areas and their needs from a harm-reduction perspective, to investigate their use of smoking crack and compare the acute effects between injecting and smoking consumption. Methods The study took place in SAPS, Barcelona, Spain. Two focus group sessions were undertaken with a total of 8 drug users. Secondly, the 8 participants answered a structured questionnaire and in the course of the sessions, as a snowball activity, were trained to survey 6 other crack smokers. Results We obtained 56 questionnaires. The majority of participants were from non-European Community countries (62.69%, 70.2% of participants referred to sharing the smoking equipment. The most frequent symptoms reported during smoked cocaine were mydriasis (83.33%, perspiration (72.92% and compulsive object search (70.83% During the group sessions, participants said that smoked cocaine is much more addictive than injected cocaine and causes more anxiety. Participants also reported the difficulty of changing from injected use to smoked use, due to the larger amount of cocaine needed to reach the same effects as when having injected. Conclusions We can conclude that the research, focused on achieving greater knowledge of the smoked cocaine user's profile, their usage of smoking crack, consumption patterns and acute effects, should be incorporated into substance misuse interventions.

  7. Amphetamine self-administration and dopamine function: assessment of gene × environment interactions in Lewis and Fischer 344 rats.

    Science.gov (United States)

    Meyer, Andrew C; Bardo, Michael T

    2015-07-01

    Previous research suggests both genetic and environmental influences on substance abuse vulnerability. The current work sought to investigate the interaction of genes and environment on the acquisition of amphetamine self-administration as well as amphetamine-stimulated dopamine (DA) release in nucleus accumbens shell using in vivo microdialysis. Inbred Lewis (LEW) and Fischer (F344) rat strains were raised in either an enriched condition (EC), social condition (SC), or isolated condition (IC). Acquisition of amphetamine self-administration (0.1 mg/kg/infusion) was determined across an incrementing daily fixed ratio (FR) schedule. In a separate cohort of rats, extracellular DA and the metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) were measured in the nucleus accumbens shell following an acute amphetamine injection (1 mg/kg). "Addiction-prone" LEW rats had greater acquisition of amphetamine self-administration on a FR1 schedule compared to "addiction-resistant" F344 rats when raised in the SC environment. These genetic differences were negated in both the EC and IC environments, with enrichment buffering against self-administration and isolation enhancing self-administration in both strains. On a FR5 schedule, the isolation-induced increase in amphetamine self-administration was greater in F344 than LEW rats. While no group differences were obtained in extracellular DA, gene × environment differences were obtained in extracellular levels of the metabolite DOPAC. In IC rats only, LEW rats showed attenuation in the amphetamine-induced decrease in DOPAC compared to F344 rats. IC LEW rats also had an attenuated DOPAC response to amphetamine compared to EC LEW rats. The current results demonstrate gene × environment interactions in amphetamine self-administration and amphetamine-induced changes in extracellular DOPAC in nucleus accumbens (NAc) shell. However, the behavioral and neurochemical differences were not related directly, indicating that

  8. Cocaine

    Science.gov (United States)

    ... Science Adolescent Brain Comorbidity College-Age & Young Adults Criminal Justice Drugged Driving Drug Testing Drugs and the ... Health Effects Statistics and Trends Swipe left or right to scroll. Monitoring the Future Study: Trends in ...

  9. Cocaine

    Science.gov (United States)

    ... something they enjoy, like eating a piece of chocolate cake or playing a video game. Normally, dopamine ... 03, 2016 The 2015 Monitoring the Future College Students and Adults survey shows trends in the use ...

  10. Levamisole-adulterated cocaine: Two fatal case reports and evaluation of possible cocaine toxicity potentiation.

    Science.gov (United States)

    Indorato, Francesca; Romano, Guido; Barbera, Nunziata

    2016-08-01

    Levamisole has been identified as a cocaine adulterant in the United States since 2002. Although there is a variation in the percentage of levamisole in cocaine samples between European countries, measurement of levamisole in human samples of cocaine users has become increasingly important. To our best knowledge, only five deaths are reported (one twice) as a result of complications secondary to levamisole-tainted cocaine and none of these cases reports the post-mortem levamisole concentration. In this article, we present the post-mortem levamisole concentrations in fluids and tissues in two young cocaine users, dead after levamisole-adulterated cocaine intake. With the dearth of levamisole reported concentrations in literature, this particular report is of interest to the forensic toxicological and pathological communities. This article aims to be a supplementary alert to aware the risk that may occur using levamisole-adulterated cocaine and an incentive to publication of toxicity reports and new researches involving the combination of levamisole and cocaine.

  11. Heroin self-administration: II. CNS gene expression following withdrawal and cue-induced drug-seeking behavior.

    Science.gov (United States)

    Kuntz, Kara L; Patel, Kruti M; Grigson, Patricia S; Freeman, Willard M; Vrana, Kent E

    2008-09-01

    In the accompanying paper, we described incubation of heroin-seeking behavior in rats following 14 days of abstinence. To gain an understanding of genomic changes that accompany this behavioral observation, we measured the expression of genes previously reported to respond to drugs of abuse. Specifically, after 1 or 14 days of abstinence, mRNA expression was measured for 11 genes in the medial prefrontal cortex (mPFC) and nucleus accumbens (NAc) immediately following a single 90 min extinction session. Additionally, the role of contingency was examined in control rats that received yoked, response-independent heroin administration. Gene expression was quantified by real-time quantitative PCR. Expression of five genes (Arc, EGR1, EGR2, Fos, and Homer1b/c) was changed in the mPFC. EGR1 and EGR2 expression was increased following the 90 min extinction session in a contingency-specific manner and this increase persisted through the 14 days of abstinence. Fos expression was also increased after 1 and 14 days of abstinence, but at 14 days this increase was response-independent (i.e., it occurred in both the rats with a history of heroin self-administration and in the yoked controls). Arc expression increased following the extinction session only in rats with a history of heroin self-administration and only when tested following 1, but not 14, days of abstinence. Homer 1 b/c decreased after 14 days of enforced abstinence in rats that received non-contingent heroin. Expression of only a single gene (EGR2) was increased in the NAc. These data demonstrate that behavioral incubation is coincident with altered levels of specific transcripts and that this response is contingently-specific. Moreover, EGR1 and EGR2 are specifically upregulated in self-administering rats following extinction and this finding persists through 14 days of abstinence, suggesting that these genes are particularly associated with the incubation phenomenon. These latter observations of persistent changes

  12. Motivation for alcohol becomes resistant to quinine adulteration after 3 to 4 months of intermittent alcohol self-administration.

    Science.gov (United States)

    Hopf, Frederic Woodward; Chang, Shao-Ju; Sparta, Dennis R; Bowers, Michael S; Bonci, Antonello

    2010-09-01

    Continued consumption of alcohol despite deleterious consequences is a hallmark of alcoholism and represents a critical challenge to therapeutic intervention. Previous rat studies showed that enduring alcohol self-administration despite pairing alcohol with normally aversive stimuli was only observed after very long-term intake (>8 months). Aversion-resistant alcohol intake has been previously interpreted to indicate pathological or compulsive motivation to consume alcohol. However, given the time required to model compulsive alcohol seeking in previous studies, there is considerable interest in developing more efficient and quantitative rodent models of aversion-resistant alcohol self-administration. Outbred Wistar rats underwent 3 to 4 months or approximately 1.5 months of intermittent, home-cage, two-bottle access (IAA) to 20% alcohol (v/v) or water. Then, after brief operant training, the effect of the bitter-tasting quinine (0.1 g/l) on the motivation to seek alcohol was quantified via progressive ratio (PR). Motivation for quinine-adulterated 2% sucrose under PR was assayed in a separate cohort of 3 to 4 months IAA rats. The effects of quinine on home-cage alcohol consumption in IAA rats and rats with continuous access to alcohol were also examined. Finally, a dose-response for quinine taste preference in IAA and continuous-access animals was determined. Motivation for alcohol after 3 to 4 months IAA, measured using an operant PR procedure, was not altered by adulteration of alcohol with 0.1 g/l quinine. In contrast, after 3 to 4 months of IAA, motivation for sucrose under PR was significantly reduced by adulteration of sucrose with 0.1 g/l quinine. In addition, motivation for alcohol after only approximately 1.5 months IAA was significantly reduced by adulteration of alcohol with 0.1 g/l quinine. Furthermore, home-cage alcohol intake by IAA rats was insensitive to quinine at concentrations (0.01, 0.03 g/l) that significantly reduced alcohol drinking in

  13. Potency of naltrexone to reduce ethanol self-administration in rats is greater for subcutaneous versus intraperitoneal injection.

    Science.gov (United States)

    Williams, Keith L; Broadbridge, Carissa L

    2009-03-01

    The opioid antagonist naltrexone (NTX) is used to treat alcohol dependence and may reduce alcohol consumption by selectively blocking opioid receptors. In rat experiments, discrepancy exists across studies regarding the potency of NTX to reduce ethanol consumption. One cause of this discrepancy may be the use of different routes of NTX administration (e.g., intraperitoneal vs. subcutaneous). The purpose of this study was to directly compare the effects of intraperitoneal and subcutaneous injections of NTX on ethanol self-administration. Rats pressed a lever for a sweetened ethanol solution (10% wt/vol in 0.1% saccharin) during 20 min daily sessions. One group received intraperitoneal injections of 1, 3, 10, and 30 mg/kg NTX before the sessions. Another group received subcutaneous injections of 0.03, 0.1, 0.3, and 1 mg/kg NTX before the sessions. The group that received subcutaneous NTX was also tested with a single intraperitoneal injection of 0.3 mg/kg NTX. Naltrexone significantly reduced ethanol self-administration, and NTX was more potent when administered via subcutaneous injection versus intraperitoneal injection. Ethanol intake (g/kg) was significantly reduced after subcutaneous injection of NTX 0.1 mg/kg and higher. In contrast, ethanol intake was significantly reduced after intraperitoneal injection of NTX 3 mg/kg and higher. A comparison of the NTX ED(50) values showed that subcutaneous NTX was approximately 30-fold more potent than intraperitoneal NTX. For the subcutaneous 0.3 mg/kg NTX dose, a detailed bin analysis showed that responding during the first 2 min after injection was similar to that during the first 2 min after a saline injection while responding after NTX decreased in subsequent bins. These findings suggest that researchers should carefully consider the route of NTX administration when discussing potency and selectivity of NTX's effects on ethanol-related behaviors in rats. These findings further support the notion that NTX acts by

  14. Drinking typography established by scheduled induction predicts chronic heavy drinking in a monkey model of ethanol self-administration.

    Science.gov (United States)

    Grant, Kathleen A; Leng, Xiaoyan; Green, Heather L; Szeliga, Kendall T; Rogers, Laura S M; Gonzales, Steven W

    2008-10-01

    We have developed an animal model of alcohol self-administration that initially employs schedule-induced polydipsia (SIP) to establish reliable ethanol consumption under open access (22 h/d) conditions with food and water concurrently available. SIP is an adjunctive behavior that is generated by constraining access to an important commodity (e.g., flavored food). The induction schedule and ethanol polydipsia generated under these conditions affords the opportunity to investigate the development of drinking typologies that lead to chronic, excessive alcohol consumption. Adult male cynomolgus monkeys (Macaca fascicularis) were induced to drink water and 4% (w/v in water) ethanol by a Fixed-Time 300 seconds (FT-300 seconds) schedule of banana-flavored pellet delivery. The FT-300 seconds schedule was in effect for 120 consecutive sessions, with daily induction doses increasing from 0.0 to 0.5 g/kg to 1.0 g/kg to 1.5 g/kg every 30 days. Following induction, the monkeys were allowed concurrent access to 4% (w/v) ethanol and water for 22 h/day for 12 months. Drinking typographies during the induction of drinking 1.5 g/kg ethanol emerged that were highly predictive of the daily ethanol intake over the next 12 months. Specifically, the frequency in which monkeys ingested 1.5 g/kg ethanol without a 5-minute lapse in drinking (defined as a bout of drinking) during induction strongly predicted (correlation 0.91) subsequent ethanol intake over the next 12 months of open access to ethanol. Blood ethanol during induction were highly correlated with intake and with drinking typography and ranged from 100 to 160 mg% when the monkeys drank their 1.5 g/kg dose in a single bout. Forty percent of the population became heavy drinkers (mean daily intakes >3.0 g/kg for 12 months) characterized by frequent "spree" drinking (intakes >4.0 g/kg/d). This model of ethanol self-administration identifies early alcohol drinking typographies (gulping the equivalent of 6 drinks) that evolve into

  15. The fast and furious : Cocaine, amphetamines and harm reduction

    NARCIS (Netherlands)

    J-P.C. Grund (Jean-Paul); P. Coffin (Philip); M. Jauffret-Roustide (Marie); M. Dijkstra (Minke); D. de Bruin (Dick); P. Blanken (Peter)

    2010-01-01

    textabstractCocaine and amphetamines (‘stimulants’) are distinct central nervous system stimulants with similar effects (Pleuvry, 2009; Holman, 1994). Cocaine is a crystalline tropane alkaloid extracted from coca leaves. Amphetamines are a subclass of phenylethylamines with primarily stimulant

  16. D-cycloserine and cocaine cue reactivity: preliminary findings.

    Science.gov (United States)

    Price, Kimber L; McRae-Clark, Aimee L; Saladin, Michael E; Maria, Megan M Moran-Santa; DeSantis, Stacia M; Back, Sudie E; Brady, Kathleen T

    2009-01-01

    D-cycloserine (DCS), a partial glutamate N-methyl-D-aspartic acid (NMDA) receptor agonist, enhances extinction of conditioned fear responding in rodents and facilitates exposure-based learning in humans with anxiety disorders. This preliminary study investigates DCS pretreatment on response to cocaine cues in cocaine-dependent subjects. Ten cocaine-dependent subjects were randomly assigned to receive either 50 mg DCS or matching placebo two hours before each of two 1-hour cocaine cue exposure sessions one day apart. HR and craving ratings were obtained before and during cue exposure sessions. There was a trend towards increased craving to cocaine cues in cocaine-dependent individuals after administration of DCS. The administration of DCS prior to cue exposure sessions may facilitate response activation. While facilitation of extinction-based learning by DCS may have therapeutic potential for cocaine dependence, this drug may exhibit a different profile in cocaine-dependent individuals as compared to those with anxiety disorders.

  17. Behavioral Screening for Cocaine Sensitivity in Mutagenized Zebrafish

    National Research Council Canada - National Science Library

    Tristan Darland; John E. Dowling

    2001-01-01

    .... Here, we report that zebrafish exhibit cocaine-induced conditioned place preference. In a pilot screen of 18 F generation families of mutagenized fish, we found three with abnormally low responses to cocaine...

  18. Motivational responses to natural and drug rewards in rats with neonatal ventral hippocampal lesions: an animal model of dual diagnosis schizophrenia.

    Science.gov (United States)

    Chambers, R Andrew; Self, David W

    2002-12-01

    The high prevalence of substance use disorders in schizophrenia relative to the general population and other psychiatric diagnoses could result from developmental neuropathology in hippocampal and cortical structures that underlie schizophrenia. In this study, we tested the effects of neonatal ventral hippocampal lesions on instrumental behavior reinforced by sucrose pellets and intravenous cocaine injections. Lesioned rats acquired sucrose self-administration faster than sham-lesioned rats, but rates of extinction were not altered. Lesioned rats also responded at higher rates during acquisition of cocaine self-administration, and tended to acquire self-administration faster. Higher response rates reflected perseveration of responding during the post-injection "time-out" periods, and a greater incidence of binge-like cocaine intake, which persisted even after cocaine self-administration stabilized. In contrast to sucrose, extinction from cocaine self-administration was prolonged in lesioned rats, and reinstatement of cocaine seeking induced by cocaine priming increased compared with shams. These results suggest that neonatal ventral hippocampal lesions facilitate instrumental learning for both natural and drug rewards, and reduce inhibitory control over cocaine taking while promoting cocaine seeking and relapse after withdrawal. The findings are discussed in terms of possible developmental or direct effects of the lesions, and both positive reinforcement (substance use vulnerability as a primary disease symptom) and negative reinforcement (self-medication) theories of substance use comorbidity in schizophrenia.

  19. Pharmacologic approaches to the treatment of cocaine dependence.

    OpenAIRE

    Taylor, W. A.; Gold, M. S.

    1990-01-01

    When pharmacologic agents are considered in the treatment of cocaine addiction, the objective of such treatment--sustained abstinence--must be considered. Medication and medical approaches have been disappointing in the treatment of cocaine overdose. The central neurobiologic mechanism(s) involved in cocaine toxicity are poorly understood. Without a cocaine antagonist, pharmacologic approaches have been less than promising in preventing relapse. Various psychoactive medications have been trie...

  20. Stress modulation of drug self-administration: implications for addiction comorbidity with post-traumatic stress disorder.

    Science.gov (United States)

    Logrip, Marian L; Zorrilla, Eric P; Koob, George F

    2012-02-01

    Drug abuse and dependence present significant health burdens for our society, affecting roughly 10% of the population. Stress likely contributes to the development and persistence of drug use; for example, rates of substance dependence are elevated among individuals diagnosed with post-traumatic stress disorder (PTSD). Thus, understanding the interaction between stress and drug use, and associated neuroadaptations, is key for developing therapies to combat substance use disorders. For this purpose, many rodent models of the effects of stress exposure on substance use have been developed; the models can be classified according to three categories of stress exposure: developmental, adult nonsocial, and adult social. The present review addresses preclinical findings on the effect of each type of trauma on responses to and self-administration of drugs of abuse by focusing on a key exemplar for each category. In addition, the potential efficacy of targeting neuropeptide systems that have been implicated in stress responses and stress system neuroadaptation in order to treat comorbid PTSD and substance abuse will be discussed. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

  1. [Inhibition of morphine intake by antibodies to serotonin-modulating anticonsolidation protein in model of self-administration in rats].

    Science.gov (United States)

    Mekhtiev, A A; Rashidova, A M; Muslimov, I A

    2014-01-01

    The article concerns study of effects of polyclonal antibodies to serotonin-modulating anticonsolidation protein (SMAP) being in direct dependence on serotonin level and providing intracellular transduction of serotonergic signal, on positive reinforcement effect of morphine in rats. The task was formed in Wistar male rats in the model of morphine self-administration as a result of pressing of one of two levers attached to the wall, joined to the pump delivering each time 100 μg of morphine directly into the vena jugularis. In the 1st series of studies brain cingulate cortex and hypothalamus were taken from the rats achieved stable level of morphine intake and SMAP level was measured with indirect immune-enzyme assay. It was shown that in the morphine-self-injected rats SMAP level in the cingulate cortex is significantly upregulated (p = 0.01), while in the hypothalamus it was left unchanged. In the 2nd series of studies the rats with stable level of morphine intake were administered intraperitoneally with anti-SMAP rabbit polyclonal antibodies (experimental group) or non-immune γ-globulins (control group). Soon after antibodies administration the animals of the experimental group demonstrated manifold decrease of morphine intake lasted for 8 days (p positive reinforcement effect of morphine. Blockade of SMAP activity with anti-SMAP antibodies in the nerve cells induced sharp decrease of morphine intake due to disturbances of transduction through intracellular serotonin's signal channels.

  2. Deconstructing the vanilla milkshake: the dominant effect of sucrose on self-administration of nutrient-flavor mixtures.

    Science.gov (United States)

    Naleid, Amy M; Grimm, Jeffrey W; Kessler, David A; Sipols, Alfred J; Aliakbari, Sepideh; Bennett, Jennifer L; Wells, Jason; Figlewicz, Dianne P

    2008-01-01

    Rats and humans avidly consume flavored foods that contain sucrose and fat, presumably due to their rewarding qualities. In this study, we hypothesized that the complex mixture of corn oil, sucrose, and flavor is more reinforcing than any of these components alone. We observed a concentration-dependent increase in reinforcers of sucrose solutions received (0%, 3%, 6.25%, and 12.5%) in both fixed ratio and progressive ratio procedures, but with equicaloric corn oil solutions (0%, 1.4%, 2.8%, and 5.6%) this finding was replicated only in the fixed ratio procedure. Likewise, addition of 1.4% oil to 3% or 12.5% sucrose increased fixed ratio, but not progressive ratio, reinforcers received relative to those of sucrose alone. Finally, addition of 3% vanilla flavoring did not change self-administration of 3% sucrose or 3% sucrose+1.4% oil solutions. These data suggest that, calorie-for-calorie, sucrose is the dominant reinforcing component of novel foods that contain a mixture of fat, sucrose, and flavor.

  3. Resistance to change of alcohol self-administration: effects of alcohol-delivery rate on disruption by extinction and naltrexone.

    Science.gov (United States)

    Jimenez-Gomez, Corina; Shahan, Timothy A

    2007-03-01

    A common finding in resistance to change research with food-maintained operant behavior is that the persistence of behavior depends on the rate of reinforcement delivered in the context in which the behavior occurs. The present experiment evaluated the effects of rate of response-dependent alcohol delivery on the resistance to change of rats' alcohol self-administration in the face of disruption produced by extinction and a range of doses of naltrexone (1.0, 3.0, 10.0 mg/kg, subcutaneous). Rats responded for a 10% alcohol solution in a multiple schedule of reinforcement arranging a higher rate of alcohol delivery (variable interval 15 s) in the presence of one stimulus and a lower rate of alcohol delivery (variable interval 45 s) in the presence of another stimulus. Baseline response rates and resistance to extinction were higher in the presence of the stimulus associated with higher rates of alcohol delivery. This finding is consistent with studies of the resistance to change of food-maintained behavior. The rate of alcohol delivered in the components, however, did not systematically affect resistance to disruption by naltrexone. One interpretation of this finding from the perspective of behavioral momentum theory is that naltrexone may decrease the impact of alcohol-associated stimuli on the persistence of drinking by reducing sensitivity to the relative reinforcement conditions arranged in the presence of different stimuli.

  4. Cocaine use severity and cerebellar gray matter are associated with reversal learning deficits in cocaine-dependent individuals

    NARCIS (Netherlands)

    Moreno-López, L.; Perales, J.C.; van Son, D.; Albein-Urios, N.; Soriano-Mas, C.; Martinez-Gonzalez, J.M.; Wiers, R.W.; Verdejo-García, A.

    2015-01-01

    Cocaine addiction involves persistent deficits to unlearn previously rewarded response options, potentially due to neuroadaptations in learning-sensitive regions. Cocaine-targeted prefrontal systems have been consistently associated with reinforcement learning and reversal deficits, but more recent

  5. Cocaine use severity and cerebellar gray matter are associated with reversal learning deficits in cocaine-dependent individuals

    NARCIS (Netherlands)

    Moreno-López, L.; Perales, J.C.; van Son, D.; Albein-Urios, N.; Soriano-Mas, C.; Martinez-Gonzalez, J.M.; Wiers, R.W.; Verdejo-García, A.

    2015-01-01

    Cocaine addiction involves persistent deficits to unlearn previously rewarded response options, potentially due to neuroadaptations in learning-sensitive regions. Cocaine-targeted prefrontal systems have been consistently associated with reinforcement learning and reversal deficits, but more recent

  6. mGlu5 Receptors and Relapse to Cocaine-Seeking: The Role of Receptor Trafficking in Postrelapse Extinction Learning Deficits

    Directory of Open Access Journals (Sweden)

    Lori A. Knackstedt

    2016-01-01

    Full Text Available We have previously demonstrated that MTEP, an allosteric antagonist of mGlu5, infused into the nucleus accumbens attenuates relapse after abstinence from cocaine self-administration. MTEP infused into the dorsolateral striatum (dlSTR does not alter relapse but has long-lasting effects on subsequent extinction learning. Here we tested whether systemic MTEP would prevent relapse after abstinence or alter extinction learning. We also investigated the mechanism of action by which intra-dlSTR MTEP on test day alters extinction on subsequent days. Animals self-administered cocaine for 12 days followed by abstinence for 20-21 days. MTEP (0.5–5 mg/kg IP was administered prior to placement into the operant chamber for a context-primed relapse test. A separate group of animals received intra-dlSTR MTEP prior to the relapse test and were sacrificed day later. Systemic administration of MTEP attenuated abstinent-relapse without significantly affecting extinction learning. Surface biotinylation analysis of protein expression in the dlSTR revealed that, in cocaine animals, intra-dlSTR MTEP administration decreased mGlu5 surface expression and prevented changes in Arc and GluA1/GluA2 observed in their vehicle counterparts. Thus, blockade of mGlu5 receptors may be utilized in future treatment strategies for relapse prevention in humans, although the effects of chronic blockade on extinction learning should be further evaluated.

  7. Contingent reinforcement of abstinence with individuals abusing cocaine and marijuana.

    OpenAIRE

    Budney, A J; Higgins, S T; Delaney, D D; Kent, L; Bickel, W K

    1991-01-01

    Two males diagnosed with cocaine dependence received a behavioral intervention comprised of contingency management and the community reinforcement approach. During the initial phase of treatment, reinforcement was delivered contingent on submitting cocaine-free urine specimens. The community reinforcement approach involved two behavior therapy sessions each week. Almost complete cocaine abstinence was achieved, but regular marijuana use continued. During a second phase, reinforcement magnitud...

  8. Limited Cutaneous Vasculitis Associated With Levamisole-Adulterated Cocaine

    Science.gov (United States)

    Yachoui, Ralph; Kolasinski, Sharon L; Eid, Hala

    2012-01-01

    Levamisole is among the many contaminants that have been detected in seized cocaine throughout North America and Europe. Little is known about the association between levamisole-adulterated cocaine and vasculitis. Herein we describe a case of limited cutaneous vasculitis manifested as retiform purpura and skin necrosis in a user of cocaine contaminated with levamisole. PMID:23024742

  9. Effects of cocaine on honey bee dance behaviour.

    Science.gov (United States)

    Barron, Andrew B; Maleszka, Ryszard; Helliwell, Paul G; Robinson, Gene E

    2009-01-01

    The role of cocaine as an addictive drug of abuse in human society is hard to reconcile with its ecological role as a natural insecticide and plant-protective compound, preventing herbivory of coca plants (Erythroxylum spp.). This paradox is often explained by proposing a fundamental difference in mammalian and invertebrate responses to cocaine, but here we show effects of cocaine on honey bees (Apis mellifera L.) that parallel human responses. Forager honey bees perform symbolic dances to advertise the location and value of floral resources to their nest mates. Treatment with a low dose of cocaine increased the likelihood and rate of bees dancing after foraging but did not otherwise increase locomotor activity. This is consistent with cocaine causing forager bees to overestimate the value of the floral resources they collected. Further, cessation of chronic cocaine treatment caused a withdrawal-like response. These similarities likely occur because in both insects and mammals the biogenic amine neuromodulator systems disrupted by cocaine perform similar roles as modulators of reward and motor systems. Given these analogous responses to cocaine in insects and mammals, we propose an alternative solution to the paradox of cocaine reinforcement. Ecologically, cocaine is an effective plant defence compound via disruption of herbivore motor control but, because the neurochemical systems targeted by cocaine also modulate reward processing, the reinforcing properties of cocaine occur as a ;side effect'.

  10. Mice lacking neuropeptide Y show increased sensitivity to cocaine

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Woldbye, David Paul Drucker

    2012-01-01

    There is increasing data implicating neuropeptide Y (NPY) in the neurobiology of addiction. This study explored the possible role of NPY in cocaine-induced behavior using NPY knockout mice. The transgenic mice showed a hypersensitive response to cocaine in three animal models of cocaine addiction...

  11. Individual differences in cocaine addiction: maladaptive behavioural traits

    NARCIS (Netherlands)

    Homberg, J.R.; Karel, P.G.A.; Verheij, M.M.M.

    2014-01-01

    Cocaine use leads to addiction in only a subset of individuals. Understanding the mechanisms underlying these individual differences in the transition from cocaine use to cocaine abuse is important to develop treatment strategies. There is agreement that specific behavioural traits increase the risk

  12. Maybe a new killer in illicit cocaine.

    Science.gov (United States)

    Fucci, Nadia

    2011-06-15

    This is the study of the author that refers about a case of a 46 years old man found dead inside his house, the death was related to cocaine intake. The police found the corpse laying in his bed with a sheet of newspaper rolled up and a few plastic coverings containing trace of cocaine on the desk. Toxicological analysis was performed and drug levels measured by means of gas chromatography/mass spectrometry technology. Based on the autopsy findings and toxicological results the cause of death was related to an acute intoxication due to cocaine "overdose". In addition to the presence of cocaine and smaller alkaloids, in the sheet made of newspaper rolled up and eluted of the nasal mucosas has been highlighted the presence of 2,6-disopropylnaphtalene (2,6-DIPN), a fungicidal pesticide very health hazard for human. A very easy, simple and selective gas chromatography mass spectrometry method was employed for the detection of 2,6-DIPN in the cocaine powder. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  13. Novel pharmacotherapeutic treatments for cocaine addiction

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    Kosten Thomas R

    2011-11-01

    Full Text Available Abstract Cocaine is a stimulant that leads to the rapid accumulation of catecholamines and serotonin in the brain due to prevention of their re-uptake into the neuron that released the neurotransmitter. Cocaine dependence is a public health concern and cause of significant morbidity and mortality worldwide. At present, there are no approved medications for the treatment of this devastating illness, and behavioral interventions have proven to be of limited use. However, there have been a number of recent trials testing promising agents including dopamine agonists, GABAergic medications and the cocaine vaccine. Here we discuss the most recent human clinical trials of potential medications for treatment of cocaine dependence, as well as pre-clinical studies for another promising agent, levo tetrahydropalmatine. Examination of these recent findings shows promise for GABAergic medications and the cocaine vaccine, as well as unique medications such as disulfiram, whose mechanism remains to be determined. Future work may also confirm specific subgroups of patients for treatment response based on clinical characteristics, biomarkers and pharmacogenetics. This review highlights the need for further, bigger studies in order to determine optimal clinical usage.

  14. Gambling Problems Among Community Cocaine Users.

    Science.gov (United States)

    Dufour, Magali; Nguyen, Noël; Bertrand, Karine; Perreault, Michel; Jutras-Aswad, Didier; Morvannou, Adèle; Bruneau, Julie; Berbiche, Djamal; Roy, Élise

    2016-09-01

    Cocaine use is highly prevalent and a major public health problem. While some studies have reported frequent comorbidity problems among cocaine users, few studies have included evaluation of gambling problems. This study aimed to estimate the prevalence of gambling problems and compare those who were at-risk gamblers with non-problem gamblers in terms of mental health problems, substance use problems, and some risk factors (i.e. family antecedents, erroneous perceptions and coping strategies) among individuals who smoke or inject cocaine. A total of 424 smoked or injected cocaine users recruited through community-based programs in Montreal (Quebec) completed the questionnaire, including the Canadian Pathological Gambling Index, the Composite International Diagnostic Interview, the CAGE, and the Severity Dependence Scale. Of the sample, 18.4 % were considered at-risk gamblers, of whom 7.8 % had problems gambling and 10.6 % were moderate-risk gamblers. The at-risk group was more likely to have experienced a recent phobic disorder and alcohol problems than the non-problem group. A multivariate analysis showed that, compared to those who were non-problem gamblers, the at-risk ones were more likely to have lost a large sum of money when they first started gambling, believed that their luck would turn, and gambled in reaction to painful life events. These results indicate the need to include routines for screening to identify gambling problem among cocaine users.

  15. Reaction mechanism for cocaine esterase-catalyzed hydrolyses of (+)- and (-)-cocaine: unexpected common rate-determining step.

    Science.gov (United States)

    Liu, Junjun; Zhao, Xinyun; Yang, Wenchao; Zhan, Chang-Guo

    2011-05-05

    First-principles quantum mechanical/molecular mechanical free energy calculations have been performed to examine the catalytic mechanism for cocaine esterase (CocE)-catalyzed hydrolysis of (+)-cocaine in comparison with CocE-catalyzed hydrolysis of (-)-cocaine. It has been shown that the acylation of (+)-cocaine consists of nucleophilic attack of the hydroxyl group of Ser117 on the carbonyl carbon of (+)-cocaine benzoyl ester and the dissociation of (+)-cocaine benzoyl ester. The first reaction step of deacylation of (+)-cocaine, which is identical to that of (-)-cocaine, is rate-determining, indicating that CocE-catalyzed hydrolyses of (+)- and (-)-cocaine have a common rate-determining step. The computational results predict that the catalytic rate constant of CocE against (+)-cocaine should be the same as that of CocE against (-)-cocaine, in contrast with the remarkable difference between human butyrylcholinesterase-catalyzed hydrolyses of (+)- and (-)-cocaine. The prediction has been confirmed by experimental kinetic analysis on CocE-catalyzed hydrolysis of (+)-cocaine in comparison with CocE-catalyzed hydrolysis of (-)-cocaine. The determined common rate-determining step indicates that rational design of a high-activity mutant of CocE should be focused on the first reaction step of the deacylation. Furthermore, the obtained mechanistic insights into the detailed differences in the acylation between the (+)- and (-)-cocaine hydrolyses provide indirect clues for rational design of amino acid mutations that could more favorably stabilize the rate-determining transition state in the deacylation and, thus, improve the catalytic activity of CocE. This study provides a valuable mechanistic base for rational design of an improved esterase for therapeutic treatment of cocaine abuse.

  16. Motivated Attention to Cocaine and Emotional Cues in Abstinent and Current Cocaine Users: An ERP Study

    Science.gov (United States)

    Dunning, Jonathan P.; Parvaz, Muhammad A.; Hajcak, Greg; Maloney, Thomas; Alia-Klein, Nelly; Woicik, Patricia A.; Telang, Frank; Wang, Gene-Jack; Volkow, Nora D.; Goldstein, Rita Z.

    2011-01-01

    Event-related potentials (ERPs) are a direct measure of neural activity and are ideally suited to study the time-course of attentional engagement with emotional and drug-related stimuli in addiction. In particular, the late positive potential (LPP) appears enhanced following cocaine-related compared to neutral stimuli in individuals with cocaine use disorders (CUD). However, previous studies have not directly compared cocaine-related to emotional stimuli while examining potential differences between abstinent and current cocaine users. The present study examined ERPs in 55 CUD (27 abstinent and 28 current users) and 29 matched healthy controls while they passively viewed pleasant, unpleasant, neutral, and cocaine-related pictures. To examine the time-course of attention to these stimuli, we analyzed both an early and later window in the LPP as well as the early posterior negativity (EPN), established in assessing motivated attention. Cocaine pictures elicited increased electrocortical measures of motivated attention in ways similar to affectively pleasant and unpleasant pictures in all CUD, an effect that was no longer discernible during the late LPP window for the current users. This group also exhibited deficient processing of the other emotional stimuli (early LPP window: pleasant pictures; late LPP window: pleasant and unpleasant pictures). Results were unique to the LPP and not EPN. Taken together, results support a relatively early attention bias to cocaine stimuli in cocaine addicted individuals further suggesting that recent cocaine use decreases such attention bias during later stages of processing but at the expense of deficient processing of other emotional stimuli. PMID:21450043

  17. Fundamental reaction mechanism and free energy profile for (-)-cocaine hydrolysis catalyzed by cocaine esterase.

    Science.gov (United States)

    Liu, Junjun; Hamza, Adel; Zhan, Chang-Guo

    2009-08-26

    The fundamental reaction mechanism of cocaine esterase (CocE)-catalyzed hydrolysis of (-)-cocaine and the corresponding free energy profile have been studied by performing pseudobond first-principles quantum mechanical/molecular mechanical free energy (QM/MM-FE) calculations. On the basis of the QM/MM-FE results, the entire hydrolysis reaction consists of four reaction steps, including the nucleophilic attack on the carbonyl carbon of (-)-cocaine benzoyl ester by the hydroxyl group of Ser117, dissociation of (-)-cocaine benzoyl ester, nucleophilic attack on the carbonyl carbon of (-)-cocaine benzoyl ester by water, and finally dissociation between the (-)-cocaine benzoyl group and Ser117 of CocE. The third reaction step involving the nucleophilic attack of a water molecule was found to be rate-determining, which is remarkably different from (-)-cocaine hydrolysis catalyzed by wild-type butyrylcholinesterase (BChE; where the formation of the prereactive BChE-(-)-cocaine complex is rate-determining) or its mutants containing Tyr332Gly or Tyr332Ala mutation (where the first chemical reaction step is rate-determining). Besides, the role of Asp259 in the catalytic triad of CocE does not follow the general concept of the "charge-relay system" for all serine esterases. The free energy barrier calculated for the rate-determining step of CocE-catalyzed hydrolysis of (-)-cocaine is 17.9 kcal/mol, which is in good agreement with the experimentally derived activation free energy of 16.2 kcal/mol. In the present study, where many sodium ions are present, the effects of counterions are found to be significant in determining the free energy barrier. The finding of the significant effects of counterions on the free energy barrier may also be valuable in guiding future mechanistic studies on other charged enzymes.

  18. Cocaine residue in plasma, cardiac and tracheal tissues of chronic cocaine-treated guinea-pigs

    Directory of Open Access Journals (Sweden)

    Malinee Wongnawa

    2010-03-01

    Full Text Available Supersensitivity of adrenoceptors to catecholamines is one of the mechanisms of cocaine-related cardiac complication. The precise mechanism of cocaine enhancing supersensitivity of adrenoceptors is unconcluded. The aim of this study was todetermine the levels of cocaine in plasma, cardiac and tracheal tissues in order to correlate with the supersensitivity ofadrenoceptors to catecholamines. In this study, two groups of ten guinea-pigs each were injected with 2.5 mg/kg cocaine or normal saline solution intraperitoneally twice daily for 14 days. After 24 hours of cocaine cessation, the cocaine levels in plasma, cardiac and tracheal tissues were determined using high performance liquid chromatography. The results showed that the cocaine levels in plasma and tracheal smooth muscle were 5.08±0.63 ng/ml and 2.8±0.41 ng/mg, respectively, while those in atria and ventricle were lower than 17.5 ng/g and 3.8 ng/g, respectively. These levels were less than the level that had been reported to block norepinephrine uptake (more than 30.34 ng/ml. Moreover, it had been demonstrated that cocainetreatment in the same condition as the present study produced supersensitivity to norepinephrine and epinephrine in isolatedguinea-pig atria as well as in trachea which is almost entirely not innervated by the adrenergic nerves. In addition, supersensitivityto oxymetazoline, isoproterenol and salbutamol which are not the substrates of neuronal reuptake were also demonstrated. All these data support the postsynaptic mechanism of cocaine enhancing supersensitivity which might be correlated with cardiac complication in chronic cocaine use.

  19. Reduced metabolism in brain "control networks" following cocaine-cues exposure in female cocaine abusers.

    Directory of Open Access Journals (Sweden)

    Nora D Volkow

    Full Text Available OBJECTIVE: Gender differences in vulnerability for cocaine addiction have been reported. Though the mechanisms are not understood, here we hypothesize that gender differences in reactivity to conditioned-cues, which contributes to relapse, are involved. METHOD: To test this we compared brain metabolism (using PET and ¹⁸FDG between female (n = 10 and male (n = 16 active cocaine abusers when they watched a neutral video (nature scenes versus a cocaine-cues video. RESULTS: Self-reports of craving increased with the cocaine-cue video but responses did not differ between genders. In contrast, changes in whole brain metabolism with cocaine-cues differed by gender (p<0.05; females significantly decreased metabolism (-8.6%±10 whereas males tended to increase it (+5.5%±18. SPM analysis (Cocaine-cues vs Neutral in females revealed decreases in frontal, cingulate and parietal cortices, thalamus and midbrain (p<0.001 whereas males showed increases in right inferior frontal gyrus (BA 44/45 (only at p<0.005. The gender-cue interaction showed greater decrements with Cocaine-cues in females than males (p<0.001 in frontal (BA 8, 9, 10, anterior cingulate (BA 24, 32, posterior cingulate (BA 23, 31, inferior parietal (BA 40 and thalamus (dorsomedial nucleus. CONCLUSIONS: Females showed greater brain reactivity to cocaine-cues than males but no differences in craving, suggesting that there may be gender differences in response to cues that are not linked with craving but could affect subsequent drug use. Specifically deactivation of brain regions from "control networks" (prefrontal, cingulate, inferior parietal, thalamus in females could increase their vulnerability to relapse since it would interfere with executive function (cognitive inhibition. This highlights the importance of gender tailored interventions for cocaine addiction.

  20. Cocaine in blood of coca chewers.

    Science.gov (United States)

    Homstedt, B; Lindgren, J E; Rivier, L; Plowman, T

    1979-01-01

    Coca leaves (Erythroxylum coca Lamarck) and powder (5 - 10 g) were taken orally by human subjects in the same way as South American natives do. The cocaine, as measured by mass fragmentography, was immediately detected in the blood, reached peak concentrations from 10 - 150 ng/ml plasma at 0.38 - 1.95 hours, and persisted in the plasma for more than 7 hours. Half-lives of the elimination of cocaine were calculated and ranged from 1.0 to 1.9 hours. The absorption half-lives ranged from 0.2 to 0.6 hours. The shape of the curves fits with the subjective effects reported. There is no reason to believe that the stimulating effect achieved by the use of either coca leaves or powder is not due to cocaine.

  1. COKE LIVe: recurrent vasculitis secondary to cocaine contaminated with levamisole.

    Science.gov (United States)

    Sandys, Vicki; Mahabir, Shanti; Byrne, Declan; Wynne, Bairbre

    2016-01-01

    Levamisole-induced vasculitis (LIV) is becoming an increasingly common entity secondary to both rising cocaine use in the UK and high levels of adulteration of cocaine with various contaminants. We report the first documented case of LIV secondary to adulterated cocaine in Ireland, which presented as a 6-year history of recurrent vasculitis of unknown aetiology. Classically, LIV is diagnosed by a combination of positive ANCA serology and agranulocytosis however, given the frequency of cocaine use, we urge acute physicians to consider the diagnosis in cases of typical retiform (angulated) purpura in association with a history of cocaine use.

  2. Vaccines against stimulants: cocaine and MA

    Science.gov (United States)

    Kosten, Thomas; Domingo, Coreen; Orson, Frank; Kinsey, Berma

    2014-01-01

    While the worldwide prevalence of cocaine use remains significant, medications, or small molecule approaches, to treat drug addictions have met with limited success. Anti-addiction vaccines, on the other hand, have demonstrated great potential for treating drug abuse using a distinctly different mechanism of eliciting an antibody response that blocks the pharmacological effects of drugs. We provide a review of vaccine-based approaches to treating stimulant addictions; specifically and cocaine addictions. This selective review article focuses on the one cocaine vaccine that has been into clinical trials and presents new data related to pre-clinical development of a methamphetamine (MA) vaccine. We also review the mechanism of action for vaccine induced antibodies to abused drugs, which involves kinetic slowing of brain entry as well as simple blocking properties. We present pre-clinical innovations for MA vaccines including hapten design, linkage to carrier proteins and new adjuvants beyond alum. We provide some new information on hapten structures and linkers and variations in protein carriers. We consider a carrier, outer membrance polysaccharide coat protein (OMPC), that provides some self-adjuvant through lipopolysaccharide components and provide new results with a monophosopholipid adjuvant for the more standard carrier proteins with cocaine and MA. The review then covers the clinical trials with the cocaine vaccine TA-CD. The clinical prospects for advances in this field over the next few years include a multi-site cocaine vaccine clinical trial to be reported in 2013 and phase 1 clinical trials of a MA vaccine in 2014. PMID:23509915

  3. The context dependency of extinction negates the effectiveness of cognitive enhancement to reduce cocaine-primed reinstatement.

    Science.gov (United States)

    Hammond, Sherri; Wagner, John J

    2013-09-01

    With respect to the treatment of addiction, the objective of extinction training is to decrease drug-seeking behavior by repeatedly exposing the patient to cues in the absence of unconditioned reinforcement. Such exposure therapy typically takes place in a novel (clinical) environment. This is potentially problematic, as the effects of extinction training include a context dependent component and therefore diminished efficacy is expected upon the patient's return to former drug-seeking/taking environments. We have reported that treatment with the NMDAR coagonist d-serine is effective in facilitating the effects of extinction to reduce cocaine-primed reinstatement. The present study assesses d-serine's effectiveness in reducing drug-primed reinstatement under conditions in which extinction training occurs in a novel environment. After 22 days of cocaine self-administration (0.5 mg/kg) in context "A", animals underwent 5 extinction training sessions in context "B". Immediately after each extinction session in "B", animals received either saline or d-serine (60 mg/kg) treatment. Our results indicate that d-serine treatment following extinction in "B" had no effect on either IV or IP cocaine-primed reinstatement conducted in "A". These results stand in contrast to our previous findings where extinction occurred in "A", indicating that d-serine's effectiveness in facilitating extinction training to reduce drug-primed reinstatement is not transferable to a novel extinction environment. This inability of d-serine treatment to reduce the context specificity of extinction training may explain the inconsistent effects observed in clinical studies published to date in which adjunctive cognitive enhancement treatment has been combined with behavioral therapy without significant benefit.

  4. Motivation for alcohol becomes resistant to quinine adulteration after 3-4 months of intermittent alcohol self-administration

    Science.gov (United States)

    Hopf, F. Woodward; Chang, Shao-Ju; Sparta, Dennis R.; Bowers, M. Scott; Bonci, Antonello

    2010-01-01

    Background Continued consumption of alcohol despite deleterious consequences is a hallmark of alcoholism and represents a critical challenge to therapeutic intervention. Previous rat studies showed that enduring alcohol self-administration despite pairing alcohol with normally aversive stimuli was only observed after very long-term intake (> 8 months). Aversion-resistant alcohol intake has been previously interpreted to indicate pathological or compulsive motivation to consume alcohol. However, given the time required to model compulsive alcohol seeking in previous studies, there is considerable interest in developing more efficient and quantitative rodent models of aversion-resistant alcohol self-administration. Methods Outbred Wistar rats underwent 3-4 months or ∼1.5 months of intermittent, home-cage, two-bottle access (IAA) to 20% alcohol (v/v) or water. Then, after brief operant training, the effect of the bitter-tasting quinine (0.1 g/L) on the motivation of to seek alcohol was quantified via progressive ratio (PR). Motivation for quinine-adulterated 2% sucrose under PR was assayed in a separate cohort of 3-4 months IAA rats. The effects of quinine on home-cage alcohol consumption in IAA rats and rats with continuous access to alcohol were also examined. Finally, a dose-response for quinine taste preference in IAA and continuous-access animals was determined. Results Motivation for alcohol after 3-4 months IAA, measured using an operant PR procedure, was not altered by adulteration of alcohol with 0.1 g/L quinine. In contrast, after 3-4 month of IAA, motivation for sucrose under PR was significantly reduced by adulteration of sucrose with 0.1 g/L quinine. In addition, motivation for alcohol after only ∼1.5 months IAA was significantly reduced by adulteration of alcohol with 0.1 g/L quinine. Furthermore, home-cage alcohol intake by IAA rats was insensitive to quinine at concentrations (0.01, 0.03 g/L) that significantly reduced alcohol drinking in animals

  5. Polysomnographic Sleep Dysregulation in Cocaine Dependence

    Directory of Open Access Journals (Sweden)

    Edwin M. Valladares

    2007-01-01

    Full Text Available Insomnia and sleep disturbance are associated with declines in health functioning, alongwith increases in mortality risk. Given the prominence of reported sleep disturbance incocaine-dependent subjects and persistence into recovery, understanding the natureand severity of these disturbances in this population may help to identify relevantpathways that contribute to the increased mortality in cocaine dependence. Polysomnography provides a means of objectively characterizing sleep and, in turn, sleep disturbances. Few studies have used polysomnography to evaluate sleep incocaine-dependent persons, yet these studies have the potential to advance treatmentsthat will ultimately reduce morbidity in cocaine-dependent subjects.

  6. Internuclear Ophthalmoplegia Secondary to Cocaine Abuse

    Directory of Open Access Journals (Sweden)

    Richard L. Rabin

    2017-01-01

    Full Text Available Purpose. To report a case of internuclear ophthalmoplegia (INO caused by cocaine. Method. We report a case of a 54-year-old female who presented with a left INO three days after snorting cocaine, and we review the literature. Results. MRI of the brain demonstrated several small abnormal foci in the pons on FLAIR and diffusion weighted imaging consistent with ischemic infarction. The patient’s symptoms remained stable throughout her hospitalization. She was sent to a rehabilitation facility and was lost to follow-up. Conclusion. In cases of extraocular movement abnormalities, it is important to inquire about recreational drug use.

  7. Can ropinirole modulate reinforcing subjective effects of cocaine in humans?

    Directory of Open Access Journals (Sweden)

    Angelo Giovanni Icro eMaremmani

    2011-08-01

    Full Text Available In this study we evaluated, by means of the Cocaine Rush Visual Analogue Scale (CRVAS, the impact of ropinirole on the expected rush induced by cocaine in a group of heroin addicts abusing cocaine; the self-reported reaction to the rush blockade (if any on cocaine consumption, and the correlations between this self-reported reaction and individual, clinical and therapeutic parameters. Nineteen cocaine abuser heroin-dependent patients entered the study. Their experienced cocaine rush was 61.31±32.1% of the maximum effect previously experienced. Compared with their previous rush intensity 16 patients experienced significantly lower intensity, three the same intensity and none a higher intensity. In particular, two patients experienced a complete blockade of rush and reported a reduced use of cocaine. Fourteen patients experienced a partial blockade of cocaine rush; of these, nine reported they had reduced their use of cocaine. Ropinirole does diminish the subjective intensity of an expected cocaine rush, so interfering with the dynamics of reward, while supporting its possible use in the treatment of cocaine dependence.

  8. A cocaine consumption study in Madrid from Social Psychology

    Directory of Open Access Journals (Sweden)

    Jesús Saiz Galdós

    2008-05-01

    Full Text Available Cocaine use in Spain is understood to be a serious problem, and this article reports two methodologically contrasting studies of the phenomenon. The first measures differences in eight variables (personality traits, personal values, attitudes towards cocaine consumption, subjective norms, behavioral perceived control, behavioral intention and socio-demographic and substance consumption among three groups of respondents, totaling 660 people. The groups are: cocaine users, people in treatment for cocaine dependence, and people who have never used cocaine. The results identify, as significant risk factors: perceived behavioral control, the values of Hedonism and Stimulation, and the personality trait of Impulsivity. In the second study, life stories are collected form 32 people with significant experience of cocaine use. These life stories reveal the sociocultural, leisure, competitive and consumerist factors that promote or facilitate cocaine and other substance use. Finally, the article considers theoretical and methodological issues, and makes a number of recommendations for drugs prevention policy.

  9. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice.

    Science.gov (United States)

    Tallarida, Christopher S; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-11-27

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this question using C57BL/6 mice. Mice pretreated with cocaine (15mg/kg×14 days) and then challenged with cocaine (15mg/kg) after 30 days of cocaine absence displayed sensitization of locomotor activity. For combination experiments, CTX injected during the 30 days of cocaine absence attenuated behavioral sensitization produced by cocaine challenge. In the case in which CTX was injected together with cocaine for 14 days, development of behavioral sensitization to cocaine challenge was also reduced. CTX attenuated the increase in locomotor activity produced by acute cocaine exposure; however, its efficacy was dependent on the dose of cocaine as inhibition was detected against 30mg/kg, but not 15mg/kg, of cocaine. These results from mice indicate that CTX attenuates locomotor activity produced by acute and repeated cocaine exposure and counters cocaine's locomotor activating properties in a paradigm in which the antibiotic is injected during the period of forced cocaine absence that follows repeated cocaine exposure.

  10. Comparative behavioral pharmacology and toxicology of cocaine and its ethanol-derived metabolite, cocaine ethyl-ester (cocaethylene)

    Energy Technology Data Exchange (ETDEWEB)

    Katz, J.L.; Terry, P.; Witkin, J.M. (NIDA Addiction Research Center, Baltimore, MD (United States))

    1992-01-01

    The present study compared the behavioral and toxic effects of cocaine and its ethanol derived metabolite, cocaine ethyl-ester (cocaethylene). Both drugs produced qualitatively similar psychomoter stimulant effects. Cocaine and cocaethylene increased locomotor activity in mice, with cocaine approximately four times more potent than cocaethylene. The durations of action of ED{sub 75} doses of each of the drugs were comparable. Each of the drugs also produced stimulation of operant responding in rats. In rats and squirrel monkeys trained to discriminate cocaine injections from saline, cocaine was approximately three to five times more potent than cocaethylene in producing these cocaine-like interoceptive effects. In contrast to the behavioral effects, cocaine and cocaethylene were equipotent in producing convulsions, and cocaethylene was more potent than cocaine in producing lethality. These results suggest that the conversion of cocaine to cocaethylene with simultaneous cocaine and alcohol use may produce an increased risk of toxicity due to a decrease in the potency of cocaethylene in producing psychomotor stimulant effects, and its increased potency in producing toxicity.

  11. Daily stressor sensitivity, abuse effects, and cocaine use in cocaine dependence.

    Science.gov (United States)

    Waldrop, Angela E; Back, Sudie E; Brady, Kathleen T; Upadhyaya, Himanshu P; McRae, Aimee L; Saladin, Michael E

    2007-12-01

    This study highlights respondent sensitivity to daily hassles as it relates to situational cocaine use and perceived long-term effects of adverse events in childhood. Data were drawn from a larger study on stress reactivity in cocaine dependent individuals. Participants (n=104) were cocaine dependent men and women without comorbid posttraumatic stress disorder (PTSD). They completed the Early Trauma Inventory (ETI), the Daily Hassles Scale (DHS), the Inventory of Drug-Taking Situations (IDTS), and the Time-Line Follow-Back (TLFB; for 90 days prior to interview). There were no gender differences in the amount or frequency of cocaine use, although the patterns of use differed between male and female users. Overall, there were some associations in the patterns of cocaine use and sensitivity to daily hassles, particularly the use in response to conflict with others. Early negative life events were positively related to response to daily hassles, but current triggers were more relevant. Reactivity to cocaine cues was related to daily hassle sensitivity among women only. Limitations and implications of the findings are discussed.

  12. Case Study: The Chemistry of Cocaine

    Science.gov (United States)

    Dewprashad, Brahmadeo

    2011-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's case study focuses on the chemistry of cocaine to teach a number of core concepts in organic chemistry. It also requires that students read and analyze an original research paper on…

  13. Cocaine-induced pulmonary changes: HRCT findings

    Directory of Open Access Journals (Sweden)

    Renata Rocha de Almeida

    2015-08-01

    Full Text Available AbstractObjective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease.Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors.Results:In 8 patients (36.4%, the clinical and tomographic findings were consistent with "crack lung", those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%, barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each.Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings.

  14. Case Study: The Chemistry of Cocaine

    Science.gov (United States)

    Dewprashad, Brahmadeo

    2011-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's case study focuses on the chemistry of cocaine to teach a number of core concepts in organic chemistry. It also requires that students read and analyze an original research paper on…

  15. Cocaine-induced pulmonary changes: HRCT findings *

    Science.gov (United States)

    de Almeida, Renata Rocha; Zanetti, Gláucia; Souza, Arthur Soares; de Souza, Luciana Soares; Silva, Jorge Luiz Pereira e; Escuissato, Dante Luiz; Irion, Klaus Loureiro; Mançano, Alexandre Dias; Nobre, Luiz Felipe; Hochhegger, Bruno; Marchiori, Edson

    2015-01-01

    Abstract Objective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease. Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors. Results: In 8 patients (36.4%), the clinical and tomographic findings were consistent with "crack lung", those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%), barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each. Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings. PMID:26398752

  16. Vulnerability to cocaine : role of stress hormones

    NARCIS (Netherlands)

    Jong, Inge Elisabeth Maria de

    2007-01-01

    Not everyone who experiments with cocaine acquires compulsive drug use. The mechanism underlying this individual difference in susceptibility to addiction is poorly understood. Recent studies have identified genes and adverse life events (stress) as risk factors. The objective of this thesis is to i

  17. Controlling Cocaine: Supplying Versus Demand Programs

    Science.gov (United States)

    1994-01-01

    programs are administered to preteens , while cocaine use does not normally start until the late teens and early twenties. 7 A primary activity of...initiation for various drugs. Prevention programs attempt to convince preteens to abstain from marijuana, cigarettes, and alcohol. Therefore, to argue that

  18. Cocaine-induced pulmonary changes: HRCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Renata Rocha de; Zanetti, Glaucia; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Programa de Pos-Graduacao em Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Petropolis, Petropolis, RJ (Brazil); Souza, Luciana Soares de [Ultra-X, Sao Jose do Rio Preto, SP (Brazil); Silva, Jorge Luiz Pereira e [Universidade Federal da Bahia (UFBA), Salvador (Brazil). Dep. de Medicina e Apoio Diagnostico; Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba (Brazil). Dept. de Clinica Medica; Irion, Klaus Loureiro [Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool (United Kingdom); Mancano, Alexandre Dias [Hospital Anchieta, Taguatinga, DF (Brazil); Nobre, Luiz Felipe [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Hochhegger, Bruno [Universidade Federal de Ciencias da Saude de Porto Alegre, Porto Alegre, RS (Brazil); Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2015-07-15

    Objective: To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease. Methods: We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors. Results: In 8 patients (36.4%), the clinical and tomographic findings were consistent with 'crack lung', those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%), barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each. Conclusions: Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings. (author)

  19. Block of a Ca(2+)-activated potassium channel by cocaine.

    Science.gov (United States)

    Premkumar, L S

    2005-04-01

    The primary target for cocaine is believed to be monoamine transporters because of cocaine's high-affinity binding that prevents re-uptake of released neurotransmitter. However, direct interaction with ion channels has been shown to be important for certain pharmacological/toxicological effects of cocaine. Here I show that cocaine selectively blocks a calcium-dependent K(+) channel in hippocampal neurons grown in culture (IC(50)=approximately 30 microM). Single-channel recordings show that in the presence of cocaine, the channel openings are interrupted with brief closures (flicker block). As the concentration of cocaine is increased the open-time is reduced, whereas the duration of brief closures is independent of concentration. The association and dissociation rate constants of cocaine for the neuronal Ca(2+)-activated K(+ )channels are 261+/-37 microM: (-1)s(-1) and 11451+/-1467 s(-1). The equilibrium dissociation constant (K(B)) for cocaine, determined from single-channel parameters, is 43 microM. The lack of voltage dependence of block suggests that cocaine probably binds to a site at the mouth of the pore. Block of Ca(2+)-dependent K(+) channels by cocaine may be involved in functions that include broadening of the action potential, which would facilitate transmitter release, enhancement of smooth muscle contraction particularly in blood vessels, and modulation of repetitive neuronal firing by altering the repolarization and afterhyperpolarization phases of the action potential.

  20. Cocaine-Associated Seizures and Incidence of Status Epilepticus

    Directory of Open Access Journals (Sweden)

    Majlesi, Nima DO

    2010-05-01

    Full Text Available Objectives: Acute complications from cocaine abuse are commonly treated in the emergency department (ED; one of the most consequential is status epilepticus. The incidence of this complication is not clearly defined in the prior literature on cocaine-associated sequelae. We evaluated the incidence of status epilepticus in patients with seizures secondary to suspected cocaine use.Methods: We performed a retrospective multi-center study of patients with seizures resulting from cocaine use. We identified study subjects at 15 hospitals by record review and conducted a computer-assisted records search to identify patients with seizures for each institution over a four-year period. We selected subjects from this group on the basis of cocaine use and determined the occurrence of status epilepticus among them. Data were collected on each subject using a standardized data collection form.Results: We evaluated 43 patients in the ED for cocaine-associated seizures. Their age range was 17 to 54, with a mean age was 31 years; 53% were male. Of 43 patients, 42 experienced a single tonic-clonic seizure and one developed status epilepticus. All patients had either a history of cocaine use or positive urine drug screen for cocaine.Conclusion: Despite reported cases of status epilepticus with cocaine-induced seizures, the incidence of this complication was unclear based on prior literature. This study shows that most cocaine-associated seizures are self-limited. [West J Emerg Med. 2010; 11(2:157-160.

  1. Operant self-administration of sweetened ethanol and time course of blood ethanol levels in adolescent and adult male Long-Evans rats.

    Science.gov (United States)

    Doherty, James M; Gonzales, Rueben A

    2015-03-01

    Little is known regarding mechanisms regulating ethanol (EtOH) self-administration during adolescence or if the mechanisms differ from adults. One of the best models of abuse liability is operant self-administration. Therefore, we characterized operant sweetened EtOH self-administration behavior in adolescent and adult rats. Adolescent (36 days old at first EtOH exposure) and adult male Long-Evans rats were first trained to self-administer 10% sucrose (10S) in an appetitive/consummatory operant model for 1 week, and then the drinking solution was switched to 10% sucrose plus 10% EtOH (10S10E) for 2 weeks. Next, rats were switched to a fixed ratio 2 schedule, and this was followed by 1 session using a progressive ratio schedule of reinforcement. Last, rats were tested for cue-induced reinstatement of lever-pressing behavior under extinction conditions after 13 days of abstinence. Blood EtOH concentration (BEC) of sweetened EtOH (self-administered or intragastric [IG] administration of 1 g/kg) was determined via gas chromatography. Control rats drank only 10S. Consumption of sweetened EtOH was not different between adolescents and adults under any schedule tested, reaching 1 g/kg in 20 minutes in the appetitive/consummatory model. Appetitive behavior directed at sweetened EtOH was less focused in adolescents versus adults. No age differences were found in motivation for sweetened EtOH. Cue-induced reinstatement of EtOH-seeking behavior after abstinence also did not differ by age. In control groups, no age difference was found in appetitive behavior or the amount of sucrose consumed, although adults exhibited greater cue-induced reinstatement. BEC after self-administration or IG administration of sweetened EtOH was higher in adults than adolescents. Consumption and motivation for sweetened EtOH are similar in adolescents and adults, although adolescents are more vulnerable to the effects of EtOH consumption on appetitive behavior. The IG results suggest larger volume

  2. Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Som, P.; Wang, G.J. [Brookhaven National Lab., Upton, NY (United States); Oster, Z.H. [State Univ. of New York, Stony Brook, NY (United States); Knapp, F.F. Jr. [Oak Ridge National Lab., TN (United States); Yonekura, Y. [Kyoto Univ. (Japan). Faculty of Medicine; Fujibayashi, Y. [Kyoto Univ. (Japan). Hospital; Yamamoto, K. [Fukui Univ. (Japan). Medical School; Kubota, K. [Tohoku Univ., Sendai (Japan)

    1992-12-31

    Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.

  3. Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Som, P.; Wang, G.J. (Brookhaven National Lab., Upton, NY (United States)); Oster, Z.H. (State Univ. of New York, Stony Brook, NY (United States)); Knapp, F.F. Jr. (Oak Ridge National Lab., TN (United States)); Yonekura, Y. (Kyoto Univ. (Japan). Faculty of Medicine); Fujibayashi, Y. (Kyoto Univ. (Japan). Hospital); Yamamoto, K. (Fukui Univ. (Japan). Medical School); Kubota, K. (Tohoku Univ., Sendai

    1992-01-01

    Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine