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Calleja-Conde J, Echeverry-Alzate V, Bühler KM, Morales-García JÁ, Segovia-Rodríguez L, Durán-González P, Olmos P, de Fonseca FR, Giné E, López-Moreno JA. Dissecting operant alcohol self-administration using saccharin-fading procedure. Neuropsychopharmacol Rep 2023; 43:12-22. [PMID: 36727594 PMCID: PMC10009421 DOI: 10.1002/npr2.12289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/02/2022] [Accepted: 08/02/2022] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Although alcohol use disorder is a complex human pathology, the use of animal models represents an opportunity to study some aspects of this pathology. One of the most used paradigms to study the voluntary alcohol consumption in rodents is operant self-administration (OSA). AIMS In order to facilitate the performance of this paradigm, we aim to describe some critical steps of OSA under a saccharin-fading procedure. MATERIAL & METHODS We used 40 male Wistar rats to study the process of acquiring the operant response through a saccharin-fading procedure under a fixed ratio (FR1) schedule of reinforcement. Next, we analyze the alcohol introduction and concentration increase, the effect of an alcohol deprivation, and the analogy between this paradigm with the Drinking in the Dark-Multiple Scheduled Access paradigm. RESULTS During alcohol concentration increase, animals reduced their lever presses in accordance with the increase in alcohol concentration. On the contrary, the consumption measured in g·kg-1 BW showed a great stability. The lever presses pattern within operant session changes with the introduction of different alcohol concentrations: at higher alcohol concentrations, animals tended to accumulate most of their presses in the initial period of the session. DISCUSSION We show the utility of fading with low concentrations of saccharin and the evolution of the operant response through the different concentrations of alcohol. CONCLUSION Taken together, our results aimed to dissect the acquisition and maintenance of OSA behavior as well as other related variables, to facilitate the understanding and performance of this paradigm.
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Affiliation(s)
| | - Víctor Echeverry-Alzate
- School of Life and Nature Sciences, Nebrija University, Madrid, Spain.,Department of Psychobiology and Methodology in Behavioral Sciences, Faculty of Psychology, Somosaguas Campus, Complutense University of Madrid, Madrid, Spain.,IMABIS Foundation, Regenerative Medicine Laboratory, Carlos Haya Regional University Hospital, Málaga, Spain
| | - Kora-Mareen Bühler
- Department of Psychobiology and Methodology in Behavioral Sciences, Faculty of Psychology, Somosaguas Campus, Complutense University of Madrid, Madrid, Spain
| | | | - Lucía Segovia-Rodríguez
- Department of Psychobiology and Methodology in Behavioral Sciences, Faculty of Psychology, Somosaguas Campus, Complutense University of Madrid, Madrid, Spain
| | - Pedro Durán-González
- Department of Psychobiology and Methodology in Behavioral Sciences, Faculty of Psychology, Somosaguas Campus, Complutense University of Madrid, Madrid, Spain
| | - Pedro Olmos
- Center for Energy, Environmental and Technological Research (CIEMAT), Madrid, Spain
| | | | - Elena Giné
- Department of Cell Biology, Faculty of Medicine, Complutense University of Madrid, Madrid, Spain
| | - Jose Antonio López-Moreno
- Department of Psychobiology and Methodology in Behavioral Sciences, Faculty of Psychology, Somosaguas Campus, Complutense University of Madrid, Madrid, Spain
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Carvajal F, Sanchez-Amate MDC, Lerma-Cabrera JM, Cubero I. Effects of a single high dose of Chlorpyrifos in long-term feeding, ethanol consumption and ethanol preference in male Wistar rats with a previous history of continued ethanol drinking. J Toxicol Sci 2014; 39:425-35. [DOI: 10.2131/jts.39.425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Francisca Carvajal
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
| | | | - José Manuel Lerma-Cabrera
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
| | - Inmaculada Cubero
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
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Maldonado-Devincci AM, Alipour KK, Michael LA, Kirstein CL. Repeated binge ethanol administration during adolescence enhances voluntary sweetened ethanol intake in young adulthood in male and female rats. Pharmacol Biochem Behav 2010; 96:476-87. [PMID: 20637794 PMCID: PMC4197847 DOI: 10.1016/j.pbb.2010.07.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 07/07/2010] [Accepted: 07/10/2010] [Indexed: 11/29/2022]
Abstract
Binge alcohol consumption is a rising concern in the United States, especially among adolescents. During this developmental period alcohol use is usually initiated and has been shown to cause detrimental effects on brain structure and function as well as cognitive/behavioral impairments in rats. Binge models, where animals are repeatedly administered high doses of ethanol typically over a period of three or four days cause these effects. There has been little work conducted aimed at investigating the long-term behavioral consequences of repeated binge administration during adolescence on later ethanol-induced behavior in young adulthood and adulthood. The repeated four-day binge model may serve as a good approximate for patterns of human adolescent alcohol consumption as this is similar to a "bender" in human alcoholics. The present set of experiments examined the dose-response and sex-related differences induced by repeated binge ethanol administration during adolescence on sweetened ethanol (Experiment 1) or saccharin (Experiment 2) intake in young adulthood. In both experiments, on postnatal days (PND) 28-31, PND 35-38 and PND 42-45, ethanol (1.5, 3.0 or 5.0 g/kg) or water was administered intragastrically to adolescent rats. Rats underwent abstinence from PND 46-59. Subsequently, in young adulthood, ethanol and saccharin intake were assessed. Exposure to any dose of ethanol during adolescence significantly enhanced ethanol intake in adulthood. However, while female rats had higher overall g/kg intake, males appear to be more vulnerable to the impact of adolescent ethanol exposure on subsequently increased ethanol intake in young adulthood. Exposure to ethanol during adolescence did not alter saccharin consumption in young adulthood in male or female rats. Considering that adolescence is the developmental period in which ethanol experimentation and consumption is usually initiated, the present set of experiments demonstrate the importance of elucidating the impact of early binge-pattern ethanol exposure on the subsequent predisposition to drink later in life.
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Affiliation(s)
| | - Kent K. Alipour
- Department of Psychology, Cognitive and Neurosciences, University of South Florida 4202 E. Fowler Avenue Tampa, FL 33620
| | | | - Cheryl L. Kirstein
- Department of Psychology, Cognitive and Neurosciences, University of South Florida 4202 E. Fowler Avenue Tampa, FL 33620
- Department of Physiology and Molecular Pharmacology, University of South Florida College of Medicine, Tampa, FL 33612
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Maldonado AM, Finkbeiner LM, Alipour KK, Kirstein CL. Voluntary ethanol consumption differs in adolescent and adult male rats using a modified sucrose-fading paradigm. Alcohol Clin Exp Res 2008; 32:1574-82. [PMID: 18616665 DOI: 10.1111/j.1530-0277.2008.00733.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Initiation of alcohol consumption during adolescence is high, which usually begins with consumption of highly concentrated sweetened alcoholic beverages in adolescent humans. Enhanced voluntary ethanol (EtOH) intake has been observed previously in adolescent relative to adult rats under continuous access conditions using sweetened EtOH solutions. The present set of experiments investigated patterns of voluntary EtOH intake in adolescent and adult rats using sweetened EtOH solutions in a limited access paradigm. METHODS Rats were trained with modified sucrose-substitution protocols that ended at either 5% sucrose-20% EtOH (5S/20E) (Exp. 1) or 5% sucrose-10% EtOH (5S/10E) (Exp. 2). RESULTS Voluntary EtOH consumption differences between the 2 age groups were apparent at higher (i.e., 10 and 20%), but not lower (i.e., 2 and 5%) EtOH concentrations. Adolescent rats consumed more EtOH on a g/kg basis only at 20% EtOH (Exp. 1). Adolescent rats voluntarily consumed more EtOH than adults when maintained at 5S/10E (Exp. 2). To assess whether these age-related differences in voluntary EtOH intake were concentration dependent, rats were trained with 5S/20E and subsequently trained with decreasing EtOH concentrations (i.e., 5S/10E and 5S/5E). Adolescents consumed more EtOH when initially presented with the 5S/10E and 5S/20E EtOH concentrations, and subsequently at the lower 5S/5E EtOH concentration (Exp. 3). There were no differences in preference for the sucrose-only solution, however adolescents tended to consume more sucrose at the 5S sucrose concentration (Exp. 4). Given that adolescents consumed more EtOH at the 5S/10E and 5S/20E, but not at the 5S/5E EtOH concentrations, preference for sucrose does not solely explain the age differences in voluntary EtOH intake observed. CONCLUSIONS Overall, results replicate previous work, demonstrating adolescent rats consume more EtOH relative to adults. However, the present results were observed using sweetened EtOH solutions in a limited access paradigm. The present modified sucrose-substitution paradigm may serve as a valid model of human adolescent drinking behavior.
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Affiliation(s)
- Antoniette M Maldonado
- Department of Psychology, Program in Cognition, Neuroscience and Social Psychology, University of South Florida, Tampa, Florida 33620, USA
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Shahan TA, Jimenez-Gomez C. Effects of self-administered alcohol concentration on the frequency and persistence of rats' attending to alcohol cues. Behav Pharmacol 2006; 17:201-11. [PMID: 16571998 DOI: 10.1097/00008877-200605000-00001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Observing responses produce contact with stimuli that are to be discriminated and have been considered an animal model of attending. In the observing-response procedure, alternating periods of drug availability versus extinction for one response are not signaled, but a second response (i.e. the observing response) produces stimuli signaling whether drug is available or not. This experiment examined the effects of the concentration of self-administered alcohol and increases in observing-response requirement on rats' observing alcohol stimuli. In addition, the effects of alcohol concentration on the persistence of observing were examined when alcohol was no longer available. Results showed that observing tracked bitonic changes in the number of alcohol deliveries rather than monotonic increases in total alcohol consumption resulting from increases in alcohol concentration. Increasing the observing-response requirement decreased the number of stimulus presentations earned. The resultant decreases in time spent in the presence of the alcohol stimulus were associated with decreases in alcohol consumption. During extinction of alcohol responding, observing was more persistent when it produced a stimulus previously associated with a higher alcohol concentration. Finally, responding for alcohol was more resistant to extinction in the presence of an observing-response-produced alcohol stimulus than in its absence, but did not depend on alcohol concentration. These results suggest that increases in the difficulty of obtaining access to alcohol cues can decrease alcohol consumption by reducing contact with those cues. In addition, if observing behavior in the present procedure is analogous to attending to alcohol cues, the results suggest that attending to alcohol cues is more persistent with cues previously associated with higher doses, and that the persistence of attending to alcohol cues and their impact on drinking may be dissociable.
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Affiliation(s)
- Timothy A Shahan
- Department of Psychology, Utah State University, Logan, Utah 84322, USA.
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Ginsburg BC, Koek W, Javors MA, Lamb RJ. Effects of fluvoxamine on a multiple schedule of ethanol- and food-maintained behavior in two rat strains. Psychopharmacology (Berl) 2005; 180:249-57. [PMID: 15682293 DOI: 10.1007/s00213-005-2156-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Accepted: 12/09/2004] [Indexed: 11/28/2022]
Abstract
RATIONALE Previous studies show that selective serotonin reuptake inhibitors (SSRIs), including fluvoxamine, have a greater effect on ethanol-maintained responding compared with an alternative reinforcer. However, none of these studies matched baseline responding for reinforcers. Because behavioral effects of many drugs depend on the baseline response rate, the preferential effects of SSRIs may be due to different baseline response rates. OBJECTIVES Fluvoxamine effects on ethanol- and food-maintained responding were compared using a multiple schedule of behavior, providing matched baseline responding and allowing within-subject analysis in two strains of rats. METHODS The multiple schedule consisted of three consecutive 5-min, fixed-ratio five components (Food1, Ethanol, Food2). Fluvoxamine (3-30 mg/kg, i.p.) was administered 30 min presession. In Lewis rats, fluvoxamine effects were determined at several available ethanol concentrations [8, 16, 32, and 8% (w/v) redetermination]. In Sprague-Dawley rats, fluvoxamine effects were determined when the available ethanol concentration was 8% (w/v). RESULTS Baseline responding was stable and well matched under all conditions except 32% ethanol, when responding for ethanol was lower than for food. After the administration of 17.8 mg/kg fluvoxamine, ethanol-maintained responding was 15-33% lower than food-maintained responding in four of the five conditions tested. Breath ethanol assessments indicated that rats had blood ethanol levels of 33 mg/dl following responding for 8% ethanol. CONCLUSIONS These results are in agreement with previous findings that SSRIs preferentially reduce ethanol-maintained responding and suggest this is not likely due to different baseline levels of responding between the comparison conditions. Further, these results support the hypothesis that alteration of synaptic serotonin can modulate ethanol reinforcement.
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Affiliation(s)
- Brett C Ginsburg
- Department of Psychiatry, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78228, USA
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Slawecki CJ, Roth J. Neurokinin Type-3 Receptor Stimulation Impairs Ethanol-Associated Appetitive Behavior in Wistar Rats. Alcohol Clin Exp Res 2003; 27:1962-70. [PMID: 14691384 DOI: 10.1097/01.alc.0000102412.53561.c6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Stimulating central neurokinin type-3 (NK-3) receptors decreases ethanol intake in rats. Although paraventricular nucleus of the hypothalamus (PVN) has a high density of NK-3 receptors, their influence on ethanol reinforcement has not been examined. This study's purpose was to assess the effects of intra-PVN infusion of senktide, a NK-3 receptor agonist, on ethanol self-administration. In a follow-up study, senktide's effects on ethanol self-administration after intracerebroventricular (ICV) infusion were examined. METHODS Male Wistar rats were trained to self-administer 10% ethanol (10E) in the "Sipper Tube" model described by Samson and colleagues, Guide cannula were then aimed bilaterally at the PVN or unilaterally at the lateral cerebral ventricle. Intra-PVN (5-100 ng/side) or ICV (30-500 ng/rat) effects of senktide on 10E self-administration were also examined as a preliminary test of senktide's selectivity. RESULTS Intra-PVN and ICV infusion of senktide reduced the average number of consecutive lever presses and increased the time taken to complete the lever press requirement when 10E served as the reinforcer. Increased duration of the lever-pressing component was observed when senktide was administered prior to 2S self-administration sessions. Neither PVN nor ICV senktide administration significantly altered 10E or 2S consumption. CONCLUSIONS These data suggest that stimulation of central neurokinin typ-3 receptors in the Wistar rat reduces appetitive behavior while having little or no impact on consummatory behavior. Ethanol "seeking" appeared more sensitive to disruption by senktide than sucrose "seeking." However, further studies assessing the senktide's effects on sucrose-maintained behavior are needed to verify this hypothesis. Lastly, it is hypothesized that lack of effect of senktide on intake is in part related to the use of outbred Wistar rats in these studies instead of selectively bred rats.
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Affiliation(s)
- Craig J Slawecki
- The Scripps Research Institute, Department of Neuropharmacology, La Jolla, CA 92037, USA.
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Abstract
Results of previous studies have shown that when rats consume higher concentrations of ethanol during initiation both the amount consumed and the pattern of consumption change with the return to a lower concentration. In this study, an across-sessions breakpoint procedure in the sipper-tube model was used to examine the effect that experience with drinking higher concentrations (a concentration manipulation) of both ethanol and sucrose had on appetitive and consummatory behaviors. A follow-up study was then conducted in the ethanol-consuming group with across-session breakpoint and intake examined before, during, and after a 3% sucrose/10% ethanol solution was presented in the sipper tube. As ethanol concentration increased, intake was not changed. Exposure to higher ethanol concentrations had no effect on the amount of 10% ethanol consumed when retested. The exposure tended to increase appetitive behavior (breakpoint), but this effect was not unique to ethanol, as rats self-administering 3% sucrose showed a similar increase. When the combined ethanol-sucrose solution was available, a significant increase in both intake and appetitive responding occurred; however, there was no change from prior intake or breakpoint when 10% ethanol was retested. That the addition of sucrose to the ethanol solution significantly increased appetitive and consummatory behaviors supports the suggestion that the composition of the alcoholic beverage can have a strong influence over the control of self-administration. Because most consumption of ethanol by human beings is in solutions that contain mixers that alter the taste of the solution, this taste factor needs to be considered in the regulation of ethanol drinking.
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Affiliation(s)
- Amanda L Sharpe
- Center for the Neurobehavioral Study of Alcohol, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1083, USA.
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Samson HH, Chappell A. Muscimol injected into the medial prefrontal cortex of the rat alters ethanol self-administration. Physiol Behav 2001; 74:581-7. [PMID: 11790418 DOI: 10.1016/s0031-9384(01)00607-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The role of the rodent prefrontal cortex in the regulation of ethanol self-administration has not been widely explored. Understanding the role of GABAergic transmission in this area in relation to ethanol self-administration is important, as the GABA system may be one of several targets for alcohol's actions in the brain. Rats were initiated to drink 10% ethanol from a dipper using a sucrose-substitution procedure. When baseline behavior was stable, bilateral microinjections of muscimol (a GABA(A) agonist) into the prefrontal cortex were tested at doses of 17.5, 30, 100 and 300 ng/microl. Ethanol self-administration was decreased by approximately 40% at the 30-ng dose and 30% at the 100-ng dose. No effects were observed at either the 17.5- or 300-ng dose. The effect on the pattern of self-administration was to shorten the size of the first run of drinking without affecting the rate of drinking. The hypothesis is put forward that the injections increased glutamatergic output to the nucleus accumbens (nAcc) that in turn increased accumbens output. This increased output is proposed as similar to the effects of dopaminergic (DA) manipulations within this system.
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Affiliation(s)
- H H Samson
- Center for the Neurobehavioral Study of Alcohol, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083, USA.
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Samson HH, Chappell A, Czachowski C, Sharpe A. Measuring ethanol-seeking behavior: the effect of using repeated extinction trials. Alcohol 2001; 24:205-9. [PMID: 11557306 DOI: 10.1016/s0741-8329(01)00157-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The development of a reliable measure of the level of ethanol-seeking behavior in an animal model is important to understanding the concept of craving. However, most existing models do not allow for the separation of the behavior associated with obtaining ethanol from that involved in consumption of ethanol. In this study, we determined the ability of repeated, single-session extinction tests in an appetitive and consummatory procedure of ethanol self-administration to assess the level of seeking behavior. The findings indicated that there were no major effects of previous extinction trials on later trials, when there were at least four reinforced sessions between tests. During reinforced sessions, the rats were consuming an average of 0.80 g of ethanol per kilogram of body weight in less than 20 min from a sipper tube. In addition, the amount of extinction responding was found to be similar to a previous measure of the appetitive strength of ethanol by using a breakpoint procedure. This method of repeated extinction tests seems to be valuable for examining the effects of pharmacological treatments that might alter ethanol seeking.
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Affiliation(s)
- H H Samson
- Center for the Neurobehavioral Study of Alcohol, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083, USA.
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Samson HH, Chappell A. Injected muscimol in pedunculopontine tegmental nucleus alters ethanol self-administration. Alcohol 2001; 23:41-8. [PMID: 11282451 DOI: 10.1016/s0741-8329(00)00122-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The pedunculopontine tegmental nucleus (PPN) has been implicated in a variety of behavioral functions, including stimulus selection. Given the PPN interactions with the mesolimbic system, it was considered important to determine its involvement in ethanol self-administration. Long-Evans male rats were trained to self-administer 10% ethanol by using a sucrose-substitution procedure. After implantation of cannula guides, microinjections of 30, 100, and 300 ng of muscimol into the PPN before the self-administration session were performed. Ethanol self-administration was decreased at the 300-ng dose, in a manner similar to the actions of dopamine agonists microinjected in the nucleus accumbens. It is hypothesized that loss of PPN cholinergic input to the mesolimbic system affects the integrative activity of the nucleus accumbens and underlies the observed change in ethanol self-administration behavior.
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Affiliation(s)
- H H Samson
- Center for the Neurobehavioral Study of Alcohol, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083, USA.
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Czachowski CL, Samson HH, Denning CE. Independent Ethanol- and Sucrose-Maintained Responding on a Multiple Schedule of Reinforcement. Alcohol Clin Exp Res 1999. [DOI: 10.1111/j.1530-0277.1999.tb04128.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Slawecki CJ, Samson HH, Chappell A. Presentation of an ethanol-paired stimulus complex alters response patterns during extinction. Pharmacol Biochem Behav 1999; 62:127-35. [PMID: 9972855 DOI: 10.1016/s0091-3057(98)00134-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
It has been hypothesized that environmental stimuli previously paired with ethanol consumption play a role in excessive ethanol intake. This study examined the ability of orally self-administered ethanol to establish a tone-light stimulus complex as a conditioned reinforcer (CSR). Male Long-Evans rats were trained to orally self-administer 10% ethanol (10E) using the sucrose-substitution procedure. During training, a tone-light stimulus complex was paired with ethanol presentation in a stimulus complex paired (SC-paired) group but not in a control group. Responding during extinction in the presence and absence of the stimulus complex was then examined. Following the initiation of ethanol self-administration, 10E maintained greater responding in the SC-paired group compared to the control group. When the stimulus complex was presented contingent on responding during extinction, the rate of extinction was slightly attenuated in the SC-paired group but not in the control group. The altered rate of extinction in the SC-paired group was characterized by: 1) a slight decrease in total session responding over successive days of extinction and 2) a transient attenuation of extinction burst response rate during the first extinction session. These data suggest the stimulus complex could function as a weak CS(R), but overall its ability to maintain lever pressing was minimal.
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Affiliation(s)
- C J Slawecki
- Department of Physiology and Pharmacology, The Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083, USA
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Abstract
The taste of ethanol can be aversive or preferred based on prior experience with ethanol consumption. A preference for ethanol's taste is thought to result from the association of ethanol's taste with its neuropharmacological activity. However, acclimation to ethanol's aversive taste may also play a role in increased ethanol consumption following prolonged exposure. The present study examined if acclimation to a bitter-sweet tastant, which has been suggested to share similar taste qualities with ethanol, would increase ethanol intake with only minimal prior experience of an association of ethanol intake with its neuropharmacological activity. Male Long-Evans rats were trained to drink 10% sucrose during 20-min sessions. The consumption of 0-20% ethanol was then determined before and after exposure to a sucrose-quinine solution. Before the sucrose-quinine taste acclimation procedure, the initial intake of sucrose-quinine was low and similar to 5% ethanol. After the acclimation procedure, increases in sucrose-quinine intake, but not ethanol intake, were observed. These data could indicate that any similarity in the taste qualities of sucrose-quinine and ethanol solutions are diminished following exposure to sucrose-quinine. Alternatively, the differential changes in sucrose-quinine and ethanol intake could be the result of being differentially regulated by a combination of taste and postingestive factors. Overall, these data indicate that exposure to sucrose-quinine, which resulted in increased intake of sucrose-quinine, was not sufficient to alter ethanol intake. Rather, exposure to taste and postingestive factors associated with ethanol may be necessary to increase ethanol intake.
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Affiliation(s)
- C J Slawecki
- Department of Physiology and Pharmacology, The Wake Forest University School of Medicine, Winston-Salem, NC, USA.
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Janak PH, Redfern JEM, Samson HH. The Reinforcing Effects of Ethanol Are Altered by the Endogenous Neurosteroid, Allopregnanolone. Alcohol Clin Exp Res 1998. [DOI: 10.1111/j.1530-0277.1998.tb03708.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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