1
|
Balakrishnan AS, Johansen LBE, Lindsley CW, Conn PJ, Thomsen M. Co-stimulation of muscarinic M1 and M4 acetylcholine receptors prevents later cocaine reinforcement in male and female mice, but not place-conditioning. Prog Neuropsychopharmacol Biol Psychiatry 2024; 134:111079. [PMID: 38950842 DOI: 10.1016/j.pnpbp.2024.111079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 06/27/2024] [Accepted: 06/28/2024] [Indexed: 07/03/2024]
Abstract
Acute stimulation of M1 or M4 muscarinic cholinergic receptors reduces cocaine abuse-related effects in mice and rats. The combined activation of these receptor subtypes produces synergistic effects on some behavioural endpoints in mice. M1 and M1 + M4 receptor stimulation in a cocaine vs. food choice assay in rats and microdialysis in rats showed delayed and lasting "anticocaine effects". Here, we tested whether these putative lasting neuroplastic changes are sufficient to occlude the reinforcing effects of cocaine at the behavioural level in mice. Mice were pre-treated with the M1 receptor partial agonist VU0364572, M4 receptor positive allosteric modulator VU0152100, or VU0364572 + VU0152100 two weeks prior to acquisition of cocaine intravenous self-administration (IVSA). Male C57BL/6JRj mice received vehicle, VU0364572, VU0152100, or VU0364572 + VU0152100. Female mice were tested with two VU0364572 + VU0152100 dose combinations or vehicle. To attribute potential effects to either reduced rewarding effects or increased aversion to cocaine, we tested VU0364572 alone and VU0364572 + VU0152100 in acquisition of cocaine-conditioned place preference (CPP) in male mice using an unbiased design. The acquisition of cocaine IVSA was drastically reduced and/or slowed in male and female mice receiving VU0364572 + VU0152100, but not either drug alone. Food-maintained operant behaviour was unaffected, indicating that the treatment effects were cocaine-specific. No treatment altered the acquisition of cocaine-CPP, neither in the post-test, nor in a challenge 14 days later. The cocaine IVSA findings confirm unusual long-lasting "anticocaine" effects of muscarinic M1 + M4 receptor stimulation. Thus, in mice, simultaneous stimulation of both receptor subtypes seems to produce potential neuroplastic changes that yield lasting effects.
Collapse
Affiliation(s)
- Abhishek Shankar Balakrishnan
- Laboratory of Neuropsychiatry, Psychiatric Centre Copenhagen, Mental Health Services in the Capital Region of Denmark and Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark; Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lærke Bornø Engelhardt Johansen
- Laboratory of Neuropsychiatry, Psychiatric Centre Copenhagen, Mental Health Services in the Capital Region of Denmark and Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Craig W Lindsley
- Warren Center for Neuroscience Drug Discovery, Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - P Jeffrey Conn
- Warren Center for Neuroscience Drug Discovery, Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Morgan Thomsen
- Laboratory of Neuropsychiatry, Psychiatric Centre Copenhagen, Mental Health Services in the Capital Region of Denmark and Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark; Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
2
|
Thomsen M, Crittenden JR, Lindsley CW, Graybiel AM. Effects of acute and repeated administration of the selective M 4 PAM VU0152099 on cocaine versus food choice in male rats. Addict Biol 2022; 27:e13145. [PMID: 35229940 PMCID: PMC9162150 DOI: 10.1111/adb.13145] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 11/29/2021] [Accepted: 01/04/2022] [Indexed: 11/30/2022]
Abstract
Ligands that stimulate muscarinic acetylcholine receptors 1 and 4 (M1 , M4 ) have shown promising effects as putative pharmacotherapy for cocaine use disorder in rodent assays. We have previously shown reductions in cocaine effects with acute M4 stimulation, as well as long-lasting, delayed reductions in cocaine taking and cocaine seeking with combined M1 /M4 receptor stimulation or with M1 stimulation alone. M4 stimulation opposes dopaminergic signalling acutely, but direct dopamine receptor antagonists have proved unhelpful in managing cocaine use disorder because they lose efficacy with long-term administration. It is therefore critical to determine whether M4 approaches themselves can remain effective with repeated or chronic dosing. We assessed the effects of repeated administration of the M4 positive allosteric modulator (PAM) VU0152099 in rats trained to choose between intravenous cocaine and a liquid food reinforcer to obtain quantitative measurement of whether M4 stimulation could produce delayed and lasting reduction in cocaine taking. VU0152099 produced progressively augmenting suppression of cocaine choice and cocaine intake, but produced neither rebound nor lasting effects after treatment ended. To compare and contrast effects of M1 versus M4 stimulation, we tested whether the M4 PAM VU0152100 suppressed cocaine self-administration in mice lacking CalDAG-GEFI signalling factor, required for M1 -mediated suppression of cocaine self-administration. CalDAG-GEFI ablation had no effect on M4 -mediated suppression of cocaine self-administration. These findings support the potential usefulness of M4 PAMs as pharmacotherapy to manage cocaine use disorder, alone or in combination with M1 -selective ligands, and show that M1 and M4 stimulation modulate cocaine-taking behaviour by distinct mechanisms.
Collapse
Affiliation(s)
- Morgane Thomsen
- Neuroscience and Behavioral Pharmacology Laboratory, Alcohol and Drug Abuse Research Center, Division of Basic Research, McLean Hospital/Harvard Medical School, Belmont, MA, USA,Laboratory of Neuropsychiatry, Psychiatric Centre Copenhagen, Mental Health Services in the Capital Region of Denmark, Copenhagen, Denmark,Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jill R. Crittenden
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Craig W. Lindsley
- Vanderbilt Program in Drug Discovery, Vanderbilt Specialized Chemistry Center (Molecular Libraries Probe Production Centers Network; MLPCN), Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Ann M. Graybiel
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
3
|
Grasing K. A threshold model for opposing actions of acetylcholine on reward behavior: Molecular mechanisms and implications for treatment of substance abuse disorders. Behav Brain Res 2016; 312:148-62. [PMID: 27316344 DOI: 10.1016/j.bbr.2016.06.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 06/11/2016] [Accepted: 06/13/2016] [Indexed: 12/26/2022]
Abstract
The cholinergic system plays important roles in both learning and addiction. Medications that modify cholinergic tone can have pronounced effects on behaviors reinforced by natural and drug reinforcers. Importantly, enhancing the action of acetylcholine (ACh) in the nucleus accumbens and ventral tegmental area (VTA) dopamine system can either augment or diminish these behaviors. A threshold model is presented that can explain these seemingly contradictory results. Relatively low levels of ACh rise above a lower threshold, facilitating behaviors supported by drugs or natural reinforcers. Further increases in cholinergic tone that rise above a second upper threshold oppose the same behaviors. Accordingly, cholinesterase inhibitors, or agonists for nicotinic or muscarinic receptors, each have the potential to produce biphasic effects on reward behaviors. Pretreatment with either nicotinic or muscarinic antagonists can block drug- or food- reinforced behavior by maintaining cholinergic tone below its lower threshold. Potential threshold mediators include desensitization of nicotinic receptors and biphasic effects of ACh on the firing of medium spiny neurons. Nicotinic receptors with high- and low- affinity appear to play greater roles in reward enhancement and inhibition, respectively. Cholinergic inhibition of natural and drug rewards may serve as mediators of previously described opponent processes. Future studies should evaluate cholinergic agents across a broader range of doses, and include a variety of reinforced behaviors.
Collapse
Affiliation(s)
- Kenneth Grasing
- From the Substance Abuse Research Laboratory, 151, Kansas City Veterans Affairs Medical Center, 4801 Linwood Boulevard, Kansas City, MO 64128, United States; From the Division of Clinical Pharmacology, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS 66160, United States.
| |
Collapse
|
4
|
Enduring effects of tacrine on cocaine-reinforced behavior: Analysis by conditioned-place preference, temporal separation from drug reward, and reinstatement. Pharmacol Res 2015; 97:40-7. [PMID: 25890194 DOI: 10.1016/j.phrs.2015.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/07/2015] [Accepted: 04/07/2015] [Indexed: 11/21/2022]
Abstract
Previous work by our laboratory has shown that tacrine can produce long-lasting reductions in cocaine-reinforced behavior, when administered to rats as daily intravenous infusions over four days. Tacrine causes dose-related liver toxicity in different species, and its manufacture for human use was recently discontinued. This study was conducted to further characterize its actions on cocaine reward. Cocaine-experienced animals that had no contact with drug over one week resumed self-administration at levels similar to their initial baseline. When tacrine was administered over four days which were preceded and followed by washout periods to allow elimination of cocaine and tacrine respectively, subsequent cocaine self-administration was attenuated by more than one-half. Tacrine administered at 10 mg/kg-day as a chronic infusion by osmotic pump did not modify cocaine-induced increases in locomotor activity or conditioned-place preference. In rats that exhibited persistent attenuation of cocaine-self-administration after receiving tacrine, cocaine-induced reinstatement was also attenuated. No changes in plasma measures of renal or hepatic function were observed in rats receiving tacrine. In conclusion, pretreatment with tacrine can decrease cocaine-motivated behavior measured by self-administration or reinstatement, but not conditioned-place preference. Reductions in cocaine self-administration following pretreatment with tacrine do not require direct interaction with cocaine and are not secondary to either liver or kidney toxicity.
Collapse
|
5
|
Gonzales KK, Smith Y. Cholinergic interneurons in the dorsal and ventral striatum: anatomical and functional considerations in normal and diseased conditions. Ann N Y Acad Sci 2015; 1349:1-45. [PMID: 25876458 DOI: 10.1111/nyas.12762] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Striatal cholinergic interneurons (ChIs) are central for the processing and reinforcement of reward-related behaviors that are negatively affected in states of altered dopamine transmission, such as in Parkinson's disease or drug addiction. Nevertheless, the development of therapeutic interventions directed at ChIs has been hampered by our limited knowledge of the diverse anatomical and functional characteristics of these neurons in the dorsal and ventral striatum, combined with the lack of pharmacological tools to modulate specific cholinergic receptor subtypes. This review highlights some of the key morphological, synaptic, and functional differences between ChIs of different striatal regions and across species. It also provides an overview of our current knowledge of the cellular localization and function of cholinergic receptor subtypes. The future use of high-resolution anatomical and functional tools to study the synaptic microcircuitry of brain networks, along with the development of specific cholinergic receptor drugs, should help further elucidate the role of striatal ChIs and permit efficient targeting of cholinergic systems in various brain disorders, including Parkinson's disease and addiction.
Collapse
Affiliation(s)
- Kalynda K Gonzales
- Yerkes National Primate Research Center, Department of Neurology and Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia.,Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York
| | - Yoland Smith
- Yerkes National Primate Research Center, Department of Neurology and Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, Georgia
| |
Collapse
|
6
|
Prast JM, Schardl A, Schwarzer C, Dechant G, Saria A, Zernig G. Reacquisition of cocaine conditioned place preference and its inhibition by previous social interaction preferentially affect D1-medium spiny neurons in the accumbens corridor. Front Behav Neurosci 2014; 8:317. [PMID: 25309368 PMCID: PMC4174134 DOI: 10.3389/fnbeh.2014.00317] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 08/27/2014] [Indexed: 11/13/2022] Open
Abstract
We investigated if counterconditioning with dyadic (i.e., one-to-one) social interaction, a strong inhibitor of the subsequent reacquisition of cocaine conditioned place preference (CPP), differentially modulates the activity of the diverse brain regions oriented along a mediolateral corridor reaching from the interhemispheric sulcus to the anterior commissure, i.e., the nucleus of the vertical limb of the diagonal band, the medial septal nucleus, the major island of Calleja, the intermediate part of the lateral septal nucleus, and the medial accumbens shell and core. We also investigated the involvement of the lateral accumbens core and the dorsal caudate putamen. The anterior cingulate 1 (Cg1) region served as a negative control. Contrary to our expectations, we found that all regions of the accumbens corridor showed increased expression of the early growth response protein 1 (EGR1, Zif268) in rats 2 h after reacquisition of CPP for cocaine after a history of cocaine CPP acquisition and extinction. Previous counterconditioning with dyadic social interaction inhibited both the reacquisition of cocaine CPP and the activation of the whole accumbens corridor. EGR1 activation was predominantly found in dynorphin-labeled cells, i.e., presumably D1 receptor-expressing medium spiny neurons (D1-MSNs), with D2-MSNs (immunolabeled with an anti-DRD2 antibody) being less affected. Cholinergic interneurons or GABAergic interneurons positive for parvalbumin, neuropeptide Y or calretinin were not involved in these CPP-related EGR1 changes. Glial cells did not show any EGR1 expression either. The present findings could be of relevance for the therapy of impaired social interaction in substance use disorders, depression, psychosis, and autism spectrum disorders.
Collapse
Affiliation(s)
- Janine M Prast
- Experimental Psychiatry Unit, Innsbruck Medical University Innsbruck, Austria
| | - Aurelia Schardl
- Experimental Psychiatry Unit, Innsbruck Medical University Innsbruck, Austria
| | | | - Georg Dechant
- Institute for Neuroscience, Innsbruck Medical University Innsbruck, Austria
| | - Alois Saria
- Experimental Psychiatry Unit, Innsbruck Medical University Innsbruck, Austria
| | - Gerald Zernig
- Experimental Psychiatry Unit, Innsbruck Medical University Innsbruck, Austria ; Department of Psychology, Leopold-Franzens University of Innsbruck Innsbruck, Austria
| |
Collapse
|
7
|
Thomsen M, Fulton BS, Caine SB. Acute and chronic effects of the M1/M4-preferring muscarinic agonist xanomeline on cocaine vs. food choice in rats. Psychopharmacology (Berl) 2014; 231:469-79. [PMID: 23995301 PMCID: PMC3947149 DOI: 10.1007/s00213-013-3256-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 08/15/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE We previously showed that the M1/M4-preferring muscarinic agonist xanomeline can acutely attenuate or eliminate cocaine self-administration in mice. OBJECTIVE 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. METHODS 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. RESULTS 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. CONCLUSIONS 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.
Collapse
Affiliation(s)
- Morgane Thomsen
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, Belmont, MA, USA,
| | | | | |
Collapse
|
8
|
Han GF, Wang M, Jin Y, Chen LZ. Synthesis and Characterization of Benzochromeno[2,3-b]tetrahydroquinolinone Derivatives. J Heterocycl Chem 2013. [DOI: 10.1002/jhet.1101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Guang-Fan Han
- Biological and Chemical Engineering Institute; Jiangsu University of Science and Technology; Zhenjiang Jiangsu 212003 China
| | - Ming Wang
- Biological and Chemical Engineering Institute; Jiangsu University of Science and Technology; Zhenjiang Jiangsu 212003 China
| | - Yan Jin
- Biological and Chemical Engineering Institute; Jiangsu University of Science and Technology; Zhenjiang Jiangsu 212003 China
| | - Li-Zhuang Chen
- Biological and Chemical Engineering Institute; Jiangsu University of Science and Technology; Zhenjiang Jiangsu 212003 China
| |
Collapse
|
9
|
Prast JM, Kummer KK, Barwitz CM, Humpel C, Dechant G, Zernig G. Acetylcholine, drug reward and substance use disorder treatment: intra- and interindividual striatal and accumbal neuron ensemble heterogeneity may explain apparent discrepant findings. Pharmacology 2012; 90:264-73. [PMID: 23018268 DOI: 10.1159/000342636] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 08/13/2012] [Indexed: 11/19/2022]
Abstract
Converging evidence from different independent laboratories suggests that acetylcholine may play an important role in drug reward and that modulation of the cholinergic system may be useful for the treatment of substance use disorders. In this commentary, we try to reconcile apparently discrepant animal behavioral, human behavioral and clinical data with a unifying hypothesis positing that the modulation of drug-versus natural stimuli-mediated reward by cholinergic interneurons in the nucleus accumbens (and the dorsal striatum) is restricted to distinct neuron ensembles that show considerable intra- and interindividual variation with respect to their spatial distribution. The precise targeting of these interindividually variable neuron ensembles would be a prerequisite for a successful pharmacotherapy based on the modulation of the cholinergic system. We also provide experimental data to support our unifying hypothesis.
Collapse
Affiliation(s)
- Janine M Prast
- Experimental Psychiatry Unit, Innsbruck Medical University, Innsbruck, Austria
| | | | | | | | | | | |
Collapse
|
10
|
Thomsen M, Lindsley CW, Conn PJ, Wessell JE, Fulton BS, Wess J, Caine SB. Contribution of both M1 and M4 receptors to muscarinic agonist-mediated attenuation of the cocaine discriminative stimulus in mice. Psychopharmacology (Berl) 2012; 220:673-85. [PMID: 21964721 PMCID: PMC3314162 DOI: 10.1007/s00213-011-2516-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 09/17/2011] [Indexed: 12/23/2022]
Abstract
RATIONALE We previously showed that muscarinic agonists with M(1) and/or M(4) receptor affinities attenuated cocaine discrimination and self-administration in wild-type mice but not in M(1)/M(4) double-knockout mice. OBJECTIVE This study aims to elucidate the respective contributions of M(1) and M(4) receptors to this effect. METHODS Knockout mice lacking either the M(1) subtype (M (1) (-/-) ) or the M(4) subtype (M (4) (-/-) ) and wild-type mice were trained to discriminate 10 mg/kg cocaine from saline. Muscarinic ligands were tested for modulation of cocaine discrimination: xanomeline (M(1)/M(4)-preferring agonist), VU0357017 (M(1)-selective partial agonist), 77-LH-28-1 (M(1) agonist), and BQCA (M(1)-selective positive allosteric modulator). RESULTS Xanomeline produced rightward shifts in the cocaine dose-effect curve in all three genotypes, but most robustly in wild-type mice. VU0357017 produced rightward shifts in the cocaine dose-effect curve in wild-type and M (4) (-/-) mice, but not in M (1) (-/-) mice. Response rates were suppressed by xanomeline in wild-type and M (1) (-/-) but not in M (4) (-/-) mice and were unaltered by VU0357017. 77-LH-28-1 and BQCA also showed evidence of attenuating cocaine's discriminative stimulus, but at doses that suppressed responding or had other undesirable effects. Intriguingly, both VU0357017 and 77-LH-28-1 exhibited U-shaped dose-effect functions in attenuating cocaine discrimination. None of the drugs substituted for the cocaine stimulus. CONCLUSIONS Attenuation of the cocaine stimulus by VU0357017 depended upon M(1) receptors, and full effects of xanomeline depended upon both M(1) and M(4) receptors. Therefore M(1)-selective agonists and mixed M(1)/M(4) agonists may be promising leads for developing medications that block cocaine's effects.
Collapse
Affiliation(s)
- Morgane Thomsen
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, Belmont, MA, USA.
| | - Craig W. Lindsley
- Vanderbilt Program in Drug Discovery, Vanderbilt Specialized Chemistry Center (Molecular Libraries Probe Production Centers Network; MLPCN), Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - P. Jeffrey Conn
- Vanderbilt Program in Drug Discovery, Vanderbilt Specialized Chemistry Center (Molecular Libraries Probe Production Centers Network; MLPCN), Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jeffrey E. Wessell
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, Belmont, Massachusetts
| | - Brian S. Fulton
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, Belmont, Massachusetts
| | - Jürgen Wess
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - S. Barak Caine
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, Belmont, Massachusetts
| |
Collapse
|
11
|
Thomsen M, Conn PJ, Lindsley C, Wess J, Boon JY, Fulton BS, Fink-Jensen A, Caine SB. Attenuation of cocaine's reinforcing and discriminative stimulus effects via muscarinic M1 acetylcholine receptor stimulation. J Pharmacol Exp Ther 2009; 332:959-69. [PMID: 19996296 DOI: 10.1124/jpet.109.162057] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
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 (4-hydroxy-2-butynyl)-1-trimethylammonium-3-chlorocarbanilate chloride (McN-A-343), and the novel M(1)-selective agonist 1-(1-2-methylbenzyl)-1,4-bipiperidin-4-yl)-1H benzo[d]imidazol-2(3H)-one (TBPB) were tested as substitution and/or pretreatment to cocaine. Both muscarinic antagonists partially substituted for cocaine and enhanced its discriminative stimulus. Conversely, muscarinic agonists blunted cocaine discrimination and abolished cocaine self-administration with varying effects on food-maintained behavior. Specifically, increasing selectivity for the M(1) subtype (oxotremorine < xanomeline < TBPB) conferred lesser nonspecific rate-suppressing effects, with no rate suppression for TBPB. In mutant mice lacking M(1) and M(4) receptors, xanomeline failed to diminish cocaine discrimination while rate-decreasing effects were intact. Our data suggest that central M(1) receptor activation attenuates cocaine's abuse-related effects, whereas non-M(1)/M(4) receptors probably contribute to undesirable effects of muscarinic stimulation. These data provide the first demonstration of anticocaine effects of systemically applied, M(1) receptor agonists and suggest the possibility of a new approach to pharmacotherapy for cocaine addiction.
Collapse
Affiliation(s)
- Morgane Thomsen
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA.
| | | | | | | | | | | | | | | |
Collapse
|