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Yadav SK, Nagar DP, Bhattacharya R. Effect of fentanyl and its three novel analogues on biochemical, oxidative, histological, and neuroadaptive markers after sub-acute exposure in mice. Life Sci 2020; 246:117400. [PMID: 32032645 DOI: 10.1016/j.lfs.2020.117400] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/19/2020] [Accepted: 02/02/2020] [Indexed: 10/25/2022]
Abstract
AIMS Comparative sub-acute toxicity, including tolerance and dependence potential of fentanyl and its three novel and potent analogues was determined in mice. MAIN METHODS Comparative sub-acute (21 d, intraperitoneal; 1/10 LD50) toxicity of fentanyl and its three novel analogues viz., N-(1-(2-phenoxyethyl)-4-piperidinyl) propionanilide (2), N-isopropyl-3-(4-(N-phenylpropionamido)piperidin-1-yl)propanamide (5), and N-t-butyl-3-(4-(N-phenylpropionamido)piperidin-1-yl)propanamide (6) was determined in mice. Animals were observed for additional seven days to assess the recovery. The brain, liver and kidney toxicity was assessed on the basis of various biochemical, oxidative, histological, and neuroadaptive markers. The expression levels of key neuronal markers associated with drug tolerance and dependence were investigated by western blot and immunohistochemistry. KEY FINDINGS Fentanyl and its analogues caused abnormal levels of liver and kidney specific biomarkers in plasma. Brain malondialdehyde (MDA) levels were raised by all the treatments and kidney MDA level by analogue 6 (21 d). Reduced glutathione levels in brain, liver, and kidney were diminished by all the treatments (21 & 28 d) and a significant change in the levels of antioxidant enzymes was also produced mainly after 21 d. The deleterious effects of fentanyl and its analogues were further substantiated by corresponding histopathological changes in brain, liver and kidney (21 & 28 d). These compounds were also found to produce neuroadaptive changes as evidenced by the increased expression levels of c-Fos, glucocorticoid receptor, N-methyl-d-aspartate receptor1 and μ-opioid receptor (21 & 28 d). SIGNIFICANCE Three novel analogues of fentanyl were envisaged to have alternative therapeutic potentials. However, their comparative sub-acute toxicity revealed undesirable side effects, thereby masking their therapeutic ability.
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Affiliation(s)
- Shiv Kumar Yadav
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474 002, M.P., India
| | - D P Nagar
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474 002, M.P., India
| | - Rahul Bhattacharya
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474 002, M.P., India.
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Tao YM, Yu C, Wang WS, Hou YY, Xu XJ, Chi ZQ, Ding YQ, Wang YJ, Liu JG. Heteromers of μ opioid and dopamine D 1 receptors modulate opioid-induced locomotor sensitization in a dopamine-independent manner. Br J Pharmacol 2017; 174:2842-2861. [PMID: 28608532 DOI: 10.1111/bph.13908] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 05/15/2017] [Accepted: 05/26/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE Exposure to opiates induces locomotor sensitization in rodents, which has been proposed to correspond to the compulsive drug-seeking behaviour. Numerous studies have demonstrated that locomotor sensitization can occur in a dopamine transmission-independent manner; however, the underlying mechanisms are unclear. EXPERIMENTAL APPROACH Co-immunoprecipitation, BRET and cross-antagonism assays were used to demonstrate the existence of receptor heterodimers. Function of heterodimers was evaluated by behavioural studies of locomotor sensitization. KEY RESULTS The dopamine D1 receptor antagonist SCH23390 antagonized the signalling initiated by stimulation of μ opioid receptors with agonists in transfected cells expressing two receptors and in striatal tissues from wild-type but not D1 receptor knockout (KO) mice, suggesting that SCH23390 modified μ receptor function via receptor heteromers, as the ability of an antagonist of one of the receptors to inhibit signals originated by stimulation of the partner receptor was a characteristic of receptor heteromers. The existence of μ receptor-D1 receptor heterodimers was further supported by biochemical and biophysical assays. In vivo, when dopamine release was absent (by destruction of the dopaminergic projection from the ventral tegmental area to the striatum), SCH23390 still significantly inhibited μ receptor agonist-induced behavioural responses in rats. Additionally, we demonstrated that D1 or μ receptor KO mice and thus unable to form μ receptor-D1 receptor heterodimers, failed to show locomotor sensitization to morphine. CONCLUSION AND IMPLICATIONS Our results suggest that μ receptor-D1 receptor heterodimers may be involved in the dopamine-independent expression of locomotor sensitization to opiates.
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Affiliation(s)
- Yi-Min Tao
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Chuan Yu
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Wei-Sheng Wang
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Yuan-Yuan Hou
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Xue-Jun Xu
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Zhi-Qiang Chi
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Yu-Qiang Ding
- Department of Anatomy and Neurobiology, Tongji University School of Medicine, Shanghai, China
| | - Yu-Jun Wang
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
| | - Jing-Gen Liu
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Science, Collaborative Innovation Center for Brain Science, Shanghai, China
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ZióŁkowska B, Gieryk A, Solecki W, PrzewŁocki R. Temporal and anatomic patterns of immediate-early gene expression in the forebrain of C57BL/6 and DBA/2 mice after morphine administration. Neuroscience 2014; 284:107-124. [PMID: 25290009 DOI: 10.1016/j.neuroscience.2014.09.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Although morphine was previously reported to produce an instant induction of c-fos in the striatum, our recent studies have demonstrated that the expression of numerous immediate early genes (IEGs) is significantly elevated at delayed time-points (several hours) after morphine administration. To better dissect the time-course of opioid-produced IEG induction, we used in situ hybridization to examine the expression of the IEGs c-fos, zif268 and arc in the mouse forebrain at several time-points after acute morphine injection. To link drug-produced behavioral changes with the activity of specific neuronal complexes, this study was performed comparatively in the C57BL/6 and DBA/2 mouse strains, which differ markedly in their locomotor responses to opioids and opioid reward. Our study demonstrates that morphine produces two episodes of IEG induction, which are separate in time (30 min vs. 4-6 h) and which have different neuroanatomic distribution. At 30 min, one or more IEGs were induced in circumscribed subregions of the dorsal striatum (dStr) and of the nucleus accumbens (NAc) shell, as well as in the lateral septum. The observed inter-strain differences in IEG expression at 30 min support earlier proposals that activation of the dorsomedial striatum may mediate morphine-elicited locomotor stimulation (both effects were present only in the C57BL/6 strain). In contrast, NAc shell activation does not appear to be linked to morphine-elicited changes in locomotor behavior. The second IEG induction (of arc and of zif268) was more widespread, involving most of the dStr and the cortex. The second IEG induction peaked earlier in the DBA/2 mice than in the C57BL/6 mice (4 h compared with 6 h) and displayed no apparent relation to locomotor behavior. This delayed episode of IEG activation, which has largely been overlooked thus far, may contribute to the development of long-term effects of opioids such as tolerance, dependence and/or addiction.
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Affiliation(s)
- B ZióŁkowska
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland.
| | - A Gieryk
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
| | - W Solecki
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; Department of Neurobiology and Neuropsychology, Institute of Applied Psychology, Jagiellonian University, Łojasiewicza 4, 30-348 Kraków, Poland
| | - R PrzewŁocki
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; Department of Neurobiology and Neuropsychology, Institute of Applied Psychology, Jagiellonian University, Łojasiewicza 4, 30-348 Kraków, Poland
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Ziółkowska B, Korostyński M, Piechota M, Kubik J, Przewłocki R. Effects of morphine on immediate-early gene expression in the striatum of C57BL/6J and DBA/2J mice. Pharmacol Rep 2013; 64:1091-104. [PMID: 23238466 DOI: 10.1016/s1734-1140(12)70906-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 05/22/2012] [Indexed: 12/25/2022]
Abstract
BACKGROUND Immediate early gene (IEG) induction elicited by drugs of abuse may contribute to development of plastic changes in the brain responsible for drug-induced behavioral changes leading to addiction. The aim of the present study was to characterize the changes in IEG expression in the striatum and nucleus accumbens produced by an acute or chronic administration of morphine. METHODS In order to search for a possible relationship between morphine-induced IEG expression and behavior, the experiment was performed on two inbred strains of mice, C57BL/6J and DBA/2J, which differ markedly in their sensitivity to the rewarding and locomotor stimulatory actions of opiates. Gene expression was assessed using RT-PCR and DNA microarrays. RESULTS The experiments demonstrated a prolonged or a delayed up-regulation of 14 IEG in the striatum at 4 h after morphine administration. Among them, a cluster of 8 genes, including 6 inducible transcription factors (c-fos, fra-2, junB, zif268 (egr1), egr2, NGFI-B) and 2 effector IEG (arc and mkp1) seemed to be regulated in concert in response to morphine. This group of genes was induced to a greater degree after chronic than acute morphine administration selectively in C57BL/6J mice and the difference bore apparently no relationship to opiate-produced locomotor activation. The strain-selective regulation was also demonstrated for cyclin L2 and tPA after an acute morphine injection. CONCLUSIONS Our data indicate that morphine up-regulates many IEG in the mouse striatum at a strikingly delayed time-point and that these changes are genotype-dependent. They also suggest inter-strain differences in the development of striatal neuroadaptations to chronic morphine treatment.
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Affiliation(s)
- Barbara Ziółkowska
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, PL 31-343 Kraków, Poland.
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Seip-Cammack KM, Reed B, Zhang Y, Ho A, Kreek MJ. Tolerance and sensitization to chronic escalating dose heroin following extended withdrawal in Fischer rats: possible role of mu-opioid receptors. Psychopharmacology (Berl) 2013; 225:127-40. [PMID: 22829433 PMCID: PMC3494815 DOI: 10.1007/s00213-012-2801-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 07/02/2012] [Indexed: 01/07/2023]
Abstract
RATIONALE/OBJECTIVES Heroin addiction is characterized by recurrent cycles of drug use, abstinence, and relapse. It is likely that neurobiological changes during chronic heroin exposure persist across withdrawal and impact behavioral responses to re-exposure. We hypothesized that, after extended withdrawal, heroin-withdrawn rats would express behavioral tolerance and/or sensitization in response to heroin re-exposure and that these responses might be associated with altered mu-opioid receptor (MOPr) activity. METHODS Male Fischer rats were exposed chronically to escalating doses of heroin (7.5-75 mg/kg/day), experienced acute spontaneous withdrawal and extended (10-day) abstinence, and were re-exposed chronically to heroin. Homecage behaviors and locomotor activity in response to heroin, as well as somatic withdrawal signs, were recorded. Separate groups of rats were sacrificed after extended abstinence and MOPr expression and G-protein coupling were analyzed using [(3)H]DAMGO and [(35)S]GTPγS assays. RESULTS The depth of behavioral stupor was lower during the initial days of heroin re-exposure compared to the initial days of the first exposure period. Behavioral responses (e.g., stereotypy) and locomotion were elevated in response to heroin re-exposure at low doses. Rats conditioned for heroin place preference during the chronic re-exposure period expressed heroin preference during acute withdrawal; this preference was stronger than rats conditioned during chronic heroin exposure that followed chronic saline and injection-free periods. Extended withdrawal was associated with increased MOPr expression in the caudate-putamen and frontal and cingulate cortices. No changes in G-protein coupling were identified. CONCLUSIONS Aspects of tolerance/sensitization to heroin are present even after extended abstinence and may be associated with altered MOPr density.
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Affiliation(s)
- Katharine M Seip-Cammack
- Laboratory of the Biology of Addictive Diseases, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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Lee B, Sur B, Yeom M, Shim I, Lee H, Hahm DH. Effect of berberine on depression- and anxiety-like behaviors and activation of the noradrenergic system induced by development of morphine dependence in rats. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2012; 16:379-86. [PMID: 23269899 PMCID: PMC3526741 DOI: 10.4196/kjpp.2012.16.6.379] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 11/05/2012] [Accepted: 11/10/2012] [Indexed: 01/12/2023]
Abstract
The purpose of this study was to evaluate whether berberine (BER) administration could attenuate depression- and anxiety-like behaviors and increase corticotrophin-releasing factor (CRF) and tyrosine hydroxylase (TH) expression following chronic morphine withdrawal in rats. Male rats were exposed to chronic, intermittent, escalating morphine (10~50 mg/kg) for 10 days. After the last morphine injection, depression- and anxiety-like beahvior associated with morphine discontinuation persisted for at least three days during withdrawal without any change in ambulatory activity. Daily BER administration significantly decreased immobility in the forced swimming test and increased open-arm exploration in the elevated plus maze test. BER administration also significantly blocked the increase in hypothalamic CRF expression and TH expression in the locus coeruleus (LC) and the decrease in hippocampal brain-derived neurotrophic factor (BDNF) mRNA expression. Taken together, these findings demonstrated that BER administration significantly reduced morphine withdrawal-associated behaviors following discontinuation of repeated morphine administration in rats, possibly through modulation of hypothalamic CRF and the central noradrenergic system. BER may be a useful agent for treating or alleviating complex withdrawal symptoms and preventing morphine use relapses.
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Affiliation(s)
- Bombi Lee
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Bongjun Sur
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Mijung Yeom
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Insop Shim
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Hyejung Lee
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Dae-Hyun Hahm
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
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Lee B, Shim I, Lee H, Yin CS, Park HK, Yang JS, Hahm DH. Morphine-induced locomotor response and Fos expression in rats are inhibited by acupuncture. Neurol Res 2010; 32 Suppl 1:107-10. [PMID: 20034457 DOI: 10.1179/016164109x12537002794444] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVES The aim of this study was to investigate the effect of acupuncture to the acupuncture point HT7 (Sinmun) on morphine-induced behavioral sensitization and the neuronal changes in nucleus accumbens and striatum in rats. METHODS Male Sprague-Dawley rats were given repeated injections of morphine hydrochloride for 5 days followed by 3 day withdrawal and one challenge injection. The acupuncture treatment was performed for 1 minute once a day for 3 days of withdrawal period and its effect on morphine-induced changes of locomotor activity and Fos expression was examined. RESULTS The acupuncture stimulation to HT7 significantly suppressed the morphine-induced increases in the locomotor activity and Fos expression in the nucleus accumbens and striatum, as compared to the controls of non-acupoint or the acupoint on other meridian. DISCUSSION These results demonstrated that the inhibitory effect of the acupuncture stimulation to HT7 on morphine-induced behavioral sensitization was closely associated with the suppression of dopamine biosynthesis and its activity in the post-synaptic neurons in nucleus accumbens and striatum. It means that the behavioral effect of the acupuncture can originate from the modulation of the same neuronal mechanism in the central dopaminergic system as in the morphine-induced behavioral sensitization. This modulation was also strictly confined to the stimulation of the specific acupoint, because the stimulation to other acupoint (TE5) on another meridian did not show the modulating effect despite being relatively close to each other. It can be therefore suggested that the acupuncture stimulation has an acupoint-specific property, and might be a useful therapeutic alternative with few side effects for treating morphine addiction.
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Affiliation(s)
- Bombi Lee
- Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul 130-701, Korea
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He L, Kim JA, Whistler JL. Biomarkers of morphine tolerance and dependence are prevented by morphine-induced endocytosis of a mutant mu-opioid receptor. FASEB J 2009; 23:4327-34. [PMID: 19679639 DOI: 10.1096/fj.09-133223] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Growing evidence shows that trafficking of the mu-opioid receptor (MOR) is a critical process in functional recovery from desensitization following activation and plays important roles in morphine tolerance and dependence largely because of the failure of morphine to promote such trafficking. However, morphine tolerance and dependence are believed to be mediated by multiple mechanisms, including well-documented biochemical changes in cAMP activity, N-methyl-D-aspartate receptors (NMDARs), glucocorticoid receptors (GRs), and c-fos. Here, we assess the consequences of promoting morphine-induced endocytosis on these biochemical changes utilizing a knock-in mouse model, RMOR, in which MORs undergo morphine-induced endocytosis. Chronic morphine treatment of wild-type (WT) mice promoted superactivation of adenylyl cyclase, alterations in NMDARs, and up-regulation of GR and c-fos in distinct brain regions. Notably, none of these biochemical changes occurred in the RMOR-knock-in mice. Together, these data demonstrate that morphine tolerance and dependence are mediated by multiple biochemical mechanisms and that MOR endocytosis plays a critical role in each of these mechanisms.
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Affiliation(s)
- Li He
- Ernest Gallo Clinic and Research Center, Department of Neurology, University of California-San Francisco, Emeryville, CA 94608, USA
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Hamlin AS, McNally GP, Fred Westbrook R, Osborne PB. Induction of Fos proteins in regions of the nucleus accumbens and ventrolateral striatum correlates with catalepsy and stereotypic behaviours induced by morphine. Neuropharmacology 2009; 56:798-807. [DOI: 10.1016/j.neuropharm.2009.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Boikess SR, Marshall JF. A sensitizing d-amphetamine regimen induces long-lasting spinophilin protein upregulation in the rat striatum and limbic forebrain. Eur J Neurosci 2008; 28:2099-107. [DOI: 10.1111/j.1460-9568.2008.06481.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ballard KA, Pellegrino TC, Alonzo NC, Nugent AL, Bayer BM. Enhanced immune sensitivity to stress following chronic morphine exposure. J Neuroimmune Pharmacol 2007; 1:106-15. [PMID: 18040796 DOI: 10.1007/s11481-005-9008-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Chronic administration of escalating doses ofmorphine leads to neuroadaptive changes precipitating development of tolerance to many of the acute effects of morphine, such as analgesia, activation of the hypothalamic-pituitary-adrenal (HPA) axis and suppression of immune cell activities. Interestingly, morphine tolerance has also been shown to be accompanied by heightened immunosuppressive effects of restraint stress using a rodent model. These observations have led to the hypothesis that the altered neuronal state accompanying opioid tolerance may contribute to this enhanced immune sensitivity to stress. To further test this hypothesis using different stressors, Sprague-Dawley rats were treated chronically with morphine for at least 8 days and then challenged with either psychological (water stress) or systemic stressors [morphine withdrawal, lipopolysaccharide (10 mug/kg i.p. challenge)]. It was found that, independent of the type of stress employed, morphine-tolerant animals displayed significantly lower mitogen-stimulated blood lymphocyte responses when compared to the responses of similarly treated saline controls. To determine whether direct activation of central stress pathways may also lead to enhanced immune sensitivity, morphine-tolerant animals were centrally injected with IL-1beta (1 ng/mul i.c.v.), a cytokine that activates the HPA axis by central mechanisms. Similar to the other types of stress, this direct central challenge was also found to be more immunosuppressive in morphine-tolerant animals compared to controls. Collectively, these studies demonstrate that morphine-tolerant animals have an enhanced susceptibility to the debilitating effects of a variety of stressors on immune cell function, an effect that is likely due to the neuroadaptive changes that develop during chronic morphine exposure.
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Affiliation(s)
- Kimberly A Ballard
- Department of Neuroscience, Georgetown University Medical Center, 3900 Reservoir Road, Washington DC 20007, USA
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Golovko AI, Golovko SI, Leontieva LV. The neurochemistry of the psychological dependence syndrome in addictive diseases of chemical etiology. NEUROCHEM J+ 2007. [DOI: 10.1134/s1819712407010011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Repeated opiate administration alters gene expression in different brain regions of rodents, an effect which may contribute to plastic changes associated with addictive behaviour. There is increasing evidence that multiple transcription factors are induced in morphine tolerance, sensitization and during morphine withdrawal. Whereas morphine treatment does not lead to major alterations in the expression of mu-opioid receptors (MOR), there is transcriptional regulation of proteins involved in MOR trafficking such as GRK2 or beta arrestin 2 as well as altered expression of other receptors such as dopamine receptors, NMDA receptors, GABA(A) receptor and alpha(2A) adrenoceptor. Recent gene expression profiling studies reveal additional clusters of morphine-responsive genes: whereas single dose administration has been shown to predominantly reduce expression of genes involved in metabolic function, ascending morphine doses leading to morphine tolerance revealed induction of genes which alter patterns of synaptic connectivity such as arc or ania-3. These genes remained elevated after precipitated withdrawal, which also triggered the expression of several transcriptional activators and repressors. In addition, morphine has been shown to be a strong inducer of heat shock protein 70, a cell protective protein which might counter-regulate opiate-induced neurotoxicity. Temporal expression profiles during a chronic morphine application schedule revealed discrete and fluctuating expression of gene clusters such as transcription factors, G-protein-coupled receptors and neuropeptides. Prolonged abstinence seems to be characterized by up-regulation of several transcription factors and persistent down-regulation of ligand gated ion channels such as glutamatergic and GABA-ergic receptor subunits. These long-term changes in receptor expression suggest a persistent alteration of synaptic signalling after morphine treatment.
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Affiliation(s)
- Susanne Ammon-Treiber
- Institute of Pharmacology and Toxicology, Otto-von-Guericke University, Magdeburg, Germany.
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Singh ME, Verty ANA, Price I, McGregor IS, Mallet PE. Modulation of morphine-induced Fos-immunoreactivity by the cannabinoid receptor antagonist SR 141716. Neuropharmacology 2004; 47:1157-69. [PMID: 15567425 DOI: 10.1016/j.neuropharm.2004.08.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2003] [Revised: 07/19/2004] [Accepted: 08/17/2004] [Indexed: 11/20/2022]
Abstract
A growing body of evidence suggests the existence of a functional interaction between opioid and cannabinoid systems. The present study further investigated this functional interaction by examining the combined effects of morphine and the cannabinoid receptor antagonist SR 141716 on Fos-immunoreactivity (Fos-IR), a marker for neural activation. Male albino Wistar rats were treated with SR 141716 (3 mg/kg, intraperitoneally), morphine HCl (10 mg/kg, subcutaneously), vehicle, or SR 141716 and morphine combined (n = 6 per group). Rats were injected with morphine or its vehicle 30-min after administration of SR 141716 or its vehicle and perfused 3 h later. Locomotor activity and body temperature were both increased in the morphine-treated group and SR 141716 significantly inhibited these effects. Morphine increased Fos-IR in several brain regions including the caudate-putamen (CPu), cortex (cingulate, insular and piriform), nucleus accumbens (NAS) shell, lateral septum (LS), bed nucleus of the stria terminalis (BNST), median preoptic nucleus (MnPO), medial preoptic nucleus (MPO), hypothalamus (paraventricular, dorsomedial and ventromedial), paraventricular thalamic nucleus (PV), amygdala (central and basolateral nuclei), dorsolateral periaqueductal gray, ventral tegmental area (VTA), and Edinger-Westphal nucleus. SR 141716 alone increased Fos-IR in the cortex (cingulate, insular and piriform), NAS (shell), LS, BNST, hypothalamus (paraventricular, dorsomedial and ventromedial), PV, amygdala (central, basolateral and medial nuclei), VTA, and Edinger-Westphal nucleus. SR 141716 attenuated morphine-induced Fos-IR in several regions including the CPu, cortex, NAS (shell), LS, MnPO, MPO, paraventricular and dorsomedial hypothalamus, PV, basolateral amygdala, VTA, and Edinger-Westphal nucleus (EW). These results provide further support for functional interplay between the cannabinoid and opioid systems. Possible behavioural and physiological implications of the interactive effects of SR 141716 on morphine-induced Fos-IR are discussed.
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Affiliation(s)
- M E Singh
- School of Psychology, University of New England, Armidale, NSW 2351, Australia
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Ferguson SM, Thomas MJ, Robinson TE. Morphine-induced c-fos mRNA expression in striatofugal circuits: modulation by dose, environmental context, and drug history. Neuropsychopharmacology 2004; 29:1664-74. [PMID: 15138436 DOI: 10.1038/sj.npp.1300465] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Opiates and psychostimulants produce many shared behavioral and neurobiological adaptations, such as behavioral sensitization and the induction of immediate early genes in the caudate-putamen (CPu). Previous studies indicate that factors such as dose, the environmental context surrounding drug administration and drug history can influence both morphine- and psychostimulant-induced behavioral sensitization. In addition, these factors can modulate the ability of psychostimulants to engage striatofugal circuits in the CPu. The present study, therefore, sought to examine whether these factors have similar influences over the ability of morphine to engage cortico-striatofugal circuits. We report that, when given in the home cage, morphine produced a small, but significant increase in the number of c-fos+ striatonigral cells and c-fos+ cells in cingulate cortex, but had no effect on the number of c-fos+ striatopallidal cells. When given in a novel test environment, however, morphine dramatically increased the number of c-fos+ striatonigral cells in a dose-dependent fashion, and this effect was maintained following repeated treatment. Unexpectedly, morphine treatment in a novel environment produced a dose-dependent reduction in the number of c-fos+ striatopallidal cells and c-fos+ cells in cingulate cortex, relative to exposure to novelty alone-effects that were reversed by repeated morphine treatment. We suggest that alterations in c-fos expression patterns in striatofugal circuits following morphine administration may be involved in drug-experience-dependent plasticity.
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Affiliation(s)
- Susan M Ferguson
- Neuroscience Program, University of Michigan, Ann Arbor, MI 48109-1109, USA
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16
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Xi ZX, Wu G, Stein EA, Li SJ. Opiate tolerance by heroin self-administration: An fMRI study in rat. Magn Reson Med 2004; 52:108-14. [PMID: 15236373 DOI: 10.1002/mrm.20119] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Functional MRI (fMRI) was employed to determine whether repeated heroin self-administration (SA) produces tolerance or sensitization in the brain of heroin-SA rats. Twelve rats were evenly divided into saline and heroin (0.06 mg/kg, 4 hr/day) SA groups. There was a progressive increase in drug-SA behavior and daily heroin intake during the 8-9 days of heroin-SA training. Within 24 hr after the last session of daily SA, acute heroin (0.1 mg/kg) administration induced regional blood oxygen level-dependent (BOLD) signals in both groups of rats. The positive BOLD signals appeared mainly in the cortical regions, including the prefrontal cortex, cingulate, and olfactory cortex, while the negative BOLD signals were predominantly located in subcortical regions such as caudate and putamen, nucleus accumbens, thalamus, and hypothalamus. However, the number of activated voxels or BOLD-signal intensity was significantly less in heroin-SA rat in regions of prefrontal cortex, nucleus accumbens, and thalamus, etc., compared to the changes in the saline control rats. Application of gamma-vinyl GABA (100 mg/kg), an irreversible GABA-transaminase inhibitor, failed to block opiate actions in the heroin-SA rats. Together, these data suggest that repeated heroin-SA produces tolerance or desensitization of opiate actions in the rat brain, which may in turn potentiate drug SA behavior and drug intake.
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Affiliation(s)
- Zheng-Xiong Xi
- Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, Maryland, USA
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17
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Viganò D, Rubino T, Di Chiara G, Ascari I, Massi P, Parolaro D. Mu opioid receptor signaling in morphine sensitization. Neuroscience 2003; 117:921-9. [PMID: 12654343 DOI: 10.1016/s0306-4522(02)00825-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We used a previously reported model of morphine sensitization that elicited a complex behavioral syndrome involving stereotyped and non stereotyped activity. To identify the mechanism of these long-lasting processes, we checked the density of mu opioid receptors, receptor-G-protein coupling and the cyclic AMP (cAMP) cascade. In morphine-sensitized animals mu opioid receptor autoradiography revealed a significant increase in the caudate putamen (30% versus controls), nucleus accumbens shell (16%), prefrontal and frontal cortex (26%), medial thalamus (43%), hypothalamus (200%) and central gray (89%). Concerning morphine's activation of G proteins in the brain, investigated in the guanylyl 5'-[gamma-(35)S]thio]triphosphate ([(35)S]GTPgammaS) binding assay, a significant increase in net [(35)S]GTPgammaS binding was seen in the caudate putamen (39%) and hypothalamus (27%). In the caudate putamen this was due to an increase in the amount of activated G proteins, and in the hypothalamus to a greater affinity of G proteins for guanosine triphosphate (GTP). The main second messenger system linked to the opioid receptor is the cAMP pathway. In the striatum basal cAMP levels were significantly elevated in sensitized animals (70% versus controls) and [D-Ala(2), N-Me-Phe(4), Gly(5)-ol]-enkephalin (DAMGO) significantly inhibited forskolin-stimulated cAMP production in control (30%) but not in sensitized rats. In the hypothalamus no significant changes were observed in basal cAMP levels and DAMGO inhibition. These cellular events induced by morphine pre-exposure could underlie the neuroadaptive processes involved in morphine sensitization.
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Affiliation(s)
- D Viganò
- Department of Pharmacology, Chemotherapy and Tossicology, University of Milan, via Vanvitelli 32, 20129, Milan, Italy
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18
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Tso PH, Wong YH. Molecular basis of opioid dependence: role of signal regulation by G-proteins. Clin Exp Pharmacol Physiol 2003; 30:307-16. [PMID: 12859419 DOI: 10.1046/j.1440-1681.2003.03835.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
1. Morphine and opiate narcotics are potent analgesics that have a high propensity to induce tolerance and physical dependence following their repeated administration. 2. The molecular basis of opiate dependence has not been completely elucidated, although the participation of opioid receptors is a prerequisite. Cellular dependence on opioids is believed to result from the chronic stimulation of opioid-regulated signalling networks. 3. As G-protein-coupled receptors, the opioid receptors must rely on heterotrimeric G-proteins for signal transduction. Recent advances in our understanding of G-protein signalling have unveiled novel signalling molecules and mechanisms, some of which may be intricately involved in the manifestation of opiate dependence. 4. In the present review, we will attempt to trace chronic opioid signals along elaborate G-protein-regulated pathways.
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Affiliation(s)
- Prudence H Tso
- Department of Biochemistry, the Molecular Neuroscience Center and The Biotechnology Research Institute, Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
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19
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Harris GC, Aston-Jones G. Enhanced morphine preference following prolonged abstinence: association with increased Fos expression in the extended amygdala. Neuropsychopharmacology 2003; 28:292-9. [PMID: 12589382 DOI: 10.1038/sj.npp.1300037] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We previously found that chronically morphine-pretreated, abstinent rats show stronger preferences for morphine-associated environments than placebo-pretreated rats. Here we show that this increased preference persisted for at least 5 weeks after withdrawal of chronic morphine. To determine brain regions involved in this behavior, we examined neural activation (as indexed by Fos-like proteins) induced by a morphine-conditioned place preference test. Placebo-pretreated (P) morphine-conditioned rats showed significantly elevated Fos in the anterior cingulate cortex (Cg), nucleus accumbens core (Ac-C) and shell (Ac-S), ventral lateral and dorsal lateral bed nucleus of the stria terminialis (BNST-VL and -DL), and central and basolateral amygdala nuclei (ACE, ABL) when compared to nonconditioned P rats. Chronically morphine-pretreated (M) rats that exhibited enhanced morphine preference 5 weeks after morphine withdrawal showed significantly greater Fos in all the same areas except the BNST-DL relative to conditioned P or nonconditioned M rats. Place preference measures and Fos expression were positively correlated in the Cg and ABL, for conditioned P animals, and in the Cg, ABL and BNST-VL for conditioned M animals. These results indicate a relationship between place preference behavior and neural indices of activation in the forebrain in response to morphine-conditioned cues that may be chronically modulated by prior morphine exposure.
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Affiliation(s)
- Glenda C Harris
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
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20
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Mayer P, Erdtmann-Vourliotis M, Riechert U, Ammon S, Höllt V. Mild stress sensitizes the brain's response to morphine. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2002; 104:143-7. [PMID: 12225868 DOI: 10.1016/s0169-328x(02)00330-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Behavioral experiments demonstrate that stress alters the individual's attitude towards opiates. In search for the underlying neuronal mechanisms we investigated the influence of stress on morphine-induced c-fos expression in the brain, and, vice versa, the influence of morphine application on the brain's c-fos response to stress. In our experiments, mild stress was induced either by brief immobilization (1 min) or by exposing the rats to a noisy and unfamiliar environment. These kinds of stress, unlike severe stress, did not elicit c-fos expression in the paraventricular nucleus of the hypothalamus. However, c-fos expression was observed in the lateral septum, medial striatum, claustrum and in the cingulate and piriform cortices under these conditions. The stress-induced c-fos induction was markedly decreased by a moderate (10 mg/kg) dose of morphine. On the other hand, morphine alone (50 mg/kg) caused only a weak c-fos expression in nai;ve animals despite of the rather high dose. If, however, this morphine dose was applied in the presence of a stressful stimulus, a pronounced c-fos expression in the dorsal striatum resulted. This c-fos signal was comparable with the signal seen in morphine-sensitized animals. Thus, distressing conditions seem to alter the brain's response to morphine at the level of gene expression, and this could be important for initiating voluntary opiate intake.
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Affiliation(s)
- P Mayer
- Institute for Pharmacology and Toxicology, Otto von Guericke University Magdeburg, Magdeburg, Germany
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21
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D'Este L, Scontrini A, Casini A, Pontieri FE, Renda TG. Heroin sensitization as mapped by c-Fos immunoreactivity in the rat striatum. Brain Res 2002; 933:144-9. [PMID: 11931859 DOI: 10.1016/s0006-8993(02)02312-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Immunohistochemistry was used to map the induction of c-Fos protein in the forebrain of rats treated with heroin. Acute injection of heroin to drug-naive rats caused significant induction of c-Fos protein in the nucleus accumbens shell, whereas the same dose of heroin given to drug-sensitized rats significantly increased c-Fos immunoreactivity in the dorsomedial caudate-putamen. These results show that the heroin-induced pattern of c-Fos protein in the rat striatum differs according to the rat's drug history. These findings may represent a neural correlate of the motor components of heroin sensitization.
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Affiliation(s)
- Loredana D'Este
- Institute of Human Anatomy, I Faculty of Medicine, Via Borelli 50, 00161, Rome, Italy.
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22
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Erdtmann-Vourliotis M, Mayer P, Ammon S, Riechert U, Höllt V. Distribution of G-protein-coupled receptor kinase (GRK) isoforms 2, 3, 5 and 6 mRNA in the rat brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2001; 95:129-37. [PMID: 11687284 DOI: 10.1016/s0006-8993(01)03046-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
There is limited knowledge about the distribution of the different G-protein-coupled receptor kinases (GRKs) in the rat brain, especially for the recently cloned isoforms GRK5 and GRK6. In this work an overview will be given of the mRNA expression patterns of four G-protein-coupled receptor kinases, GRK2 (betaARK1), GRK3 (betaARK2), GRK5 and GRK6 in the rat brain. As now shown by us and recently by others GRK2 and GRK3 are widely distributed in rat brain with nearly the same expression pattern. But GRK3, in general, appeared to be weaker expressed than GRK2 in most brain areas. Exceptions were the islands of Calleja, the compact part of the substantia nigra and the locus coeruleus. GRK3 mRNA was very low expressed or absent in the striatum and in some hypothalamic and thalamic nuclei. The expression pattern of GRK6 was also similar to GRK2. In the caudate putamen GRK6 yielded the strongest hybridization signal of all GRK types. GRK5 took a special position. The message for this form was not expressed ubiquitously in the brain but was mainly localized in limbic brain regions with a very prominent expression in the lateral septal area. GRK5 may therefore be involved in reward and addiction. Accordingly, a higher expression level of GRK5 mRNA was found in the lateral septum of cocaine-sensitized rats as compared to controls.
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Affiliation(s)
- M Erdtmann-Vourliotis
- Institute for Pharmacology and Toxicology, Otto-von-Guericke-Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
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23
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Abstract
People with a genetic predisposition for substance abuse have defects in genes for the opioid peptides and receptors. A high number of polymorphisms have been detected in the mu-opioid receptor, some of which result in pharmacological alterations. The opioid peptide proopiomelanocortin proved extraordinarily rich in mutations that often lead to severe phenotypical consequences. Prodynorphin displays a polymorphic regulation of transcription. Variants of the mu- and the delta-opioid receptor showed positive associations with opiate and/or alcohol addiction in some studies. However, these associations were weak, indicating a small contribution of the opioid system to these disorders.
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MESH Headings
- Alleles
- Enkephalins/genetics
- Enkephalins/pharmacology
- Genetic Predisposition to Disease
- Humans
- Polymorphism, Genetic
- Protein Precursors/genetics
- Protein Precursors/pharmacology
- Receptors, Opioid, delta/genetics
- Receptors, Opioid, delta/physiology
- Receptors, Opioid, kappa/genetics
- Receptors, Opioid, kappa/physiology
- Receptors, Opioid, mu/genetics
- Receptors, Opioid, mu/physiology
- Substance-Related Disorders/genetics
- beta-Endorphin/genetics
- beta-Endorphin/pharmacology
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Affiliation(s)
- P Mayer
- Institute for Pharmacology and Toxicology, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
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24
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Abstract
This paper is the twenty-second installment of the annual review of research concerning the opiate system. It summarizes papers published during 1999 that studied the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects, although stress-induced analgesia is included. The specific topics covered this year include stress; tolerance and dependence; learning, memory, and reward; eating and drinking; alcohol and other drugs of abuse; sexual activity, pregnancy, and development; mental illness and mood; seizures and other neurologic disorders; electrical-related activity; general activity and locomotion; gastrointestinal, renal, and hepatic function; cardiovascular responses; respiration and thermoregulation; and immunologic responses.
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Affiliation(s)
- A L Vaccarino
- Department of Psychology, University of New Orleans, New Orleans, LA 70148, USA.
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25
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Erdtmann-Vourliotis M, Mayer P, Riechert U, Höllt V. Prior experience of morphine application alters the c-fos response to MDMA ('ecstasy') and cocaine in the rat striatum. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2000; 77:55-64. [PMID: 10814832 DOI: 10.1016/s0169-328x(00)00040-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Repeated morphine application usually leads to the development of tolerance but under certain circumstances sensitization may arise simultaneously. This phenomenon becomes obvious in behavioral tests as increasing locomotor activity and increasing drug self-administration during a course of chronic morphine application. It was suggested recently that sensitization could contribute to addiction. The molecular mechanisms of sensitization may include the long lasting increase in neuronal responsiveness to morphine which was observed in defined brain areas after repeated morphine injections. In this work, we studied whether morphine-sensitized Wistar rats also display an enhanced neuronal activity in response to other drugs of abuse (so called co-sensitization). The substances to be tested were injected as single doses 4 weeks after completion of a 10-day morphine pretreatment. MDMA (3, 4-methylenedioxymethamphetamine, 6 mg/kg) as a single test dose yielded a c-fos response in a wide range of brain areas. In the caudate putamen, the expression pattern of c-fos was clearly altered if the rats had received repeated morphine application previously. In this case, the MDMA-induced c-fos expression was markedly confined to the centromedial, mesolimbic aspect of the striatum whereas it had a diffuse appearance in rats not exposed to the opiate earlier. Cocaine application (50 mg/kg) elicited an intense c-fos expression in the medial striatum if the animals were morphine-pretreated; it was virtually absent in drug-naive rats after the same cocaine dose. Ten mg/kg cocaine had a similar but weaker effect. No difference in the c-fos expression pattern between morphine and saline pretreated animals was observed in the case of a THC (Delta(9)-tetrahydrocannabinol, 25 mg/kg) or an LSD (lysergic acid diethylamide, 1 mg/kg) test application. These findings imply that morphine sensitizes the brain towards other addicting drugs. In consequence, morphine sensitization obviously does not solely reflect alterations in mu-opioid receptor signaling. Rather, it seems to reflect further rearrangements within the mesolimbic system.
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Affiliation(s)
- M Erdtmann-Vourliotis
- Institute for Pharmacology and Toxicology, Otto-von-Guericke Universität, Leipziger Str. 44, 39120, Magdeburg, Germany
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26
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Erdtmann-Vourliotis M, Mayer P, Riechert U, Höllt V. Acute injection of drugs with low addictive potential (delta(9)-tetrahydrocannabinol, 3,4-methylenedioxymethamphetamine, lysergic acid diamide) causes a much higher c-fos expression in limbic brain areas than highly addicting drugs (cocaine and morphine). BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 71:313-24. [PMID: 10521585 DOI: 10.1016/s0169-328x(99)00207-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It is regarded as a common pharmacological property responsible for the addictive potential of drugs of abuse that they are able to activate brain areas involved in the sensation of pleasure, especially the nucleus accumbens. To investigate the connection between addictive potential and stimulation of critical brain areas in more detail, we studied c-fos accumulation in response to various addicting drugs in direct comparison. The substances were injected into drug-naive rats, and c-fos mRNA levels were measured throughout the brain by in situ hybridization. Cocaine in a high dose of 50 mg/kg yielded only a discrete c-fos expression in the medial and central striatum. Morphine (50 mg/kg) caused a weak c-fos synthesis in the lateral septum. THC (delta(9)-tetrahydrocannabinol), 25 mg/kg, induced c-fos mRNA again in the lateral septum and furthermore in large parts of the striatum including the nucleus accumbens. LSD (lysergic acid diamide), 1 mg/kg, elicited a similar c-fos expression pattern as THC, but there was additionally a very strong hybridization signal in the cerebral cortex, especially in the upper layers, and in the ventral part of the periaqueductal gray. The widest range of brain areas was activated by MDMA (3, 4-methylenedioxymethamphetamine, 'ecstasy'), 6 mg/kg. In addition to the regions that responded to LSD, there was a very pronounced c-fos signal in the nucleus accumbens core and shell and in the mammillary nuclei. Taken together, our study revealed that the drugs with the highest addictive potential, cocaine and morphine, yielded a very low c-fos synthesis throughout the brain whereas the brain regions closely linked to pleasure (especially the nucleus accumbens) responded strongly to drugs with an apparently lower addictive potential (THC, LSD, MDMA).
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Affiliation(s)
- M Erdtmann-Vourliotis
- Institute for Pharmacology and Toxicology, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
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