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Ponzoni L, Braida D, Bondiolotti G, Sala M. The Non-Peptide Arginine-Vasopressin v 1a Selective Receptor Antagonist, SR49059, Blocks the Rewarding, Prosocial, and Anxiolytic Effects of 3,4-Methylenedioxymethamphetamine and Its Derivatives in Zebra Fish. Front Psychiatry 2017; 8:146. [PMID: 28855876 PMCID: PMC5557732 DOI: 10.3389/fpsyt.2017.00146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 07/27/2017] [Indexed: 01/23/2023] Open
Abstract
3,4-Methylenedioxymethamphetamine (MDMA) and its derivatives, 2,5-dimethoxy-4-bromo-amphetamine hydrobromide (DOB) and para-methoxyamphetamine (PMA), are recreational drugs whose pharmacological effects have recently been attributed to serotonin 5HT2A/C receptors. However, there is growing evidence that the oxytocin (OT)/vasopressin system can modulate some the effects of MDMA. In this study, MDMA (2.5-10 mg/kg), DOB (0.5 mg/kg), or PMA (0.005, 0.1, or 0.25 mg/kg) were administered intramuscularly to adult zebra fish, alone or in combination with the V1a vasopressin antagonist, SR49059 (0.01-1 ng/kg), before carrying out conditioned place preference (CPP), social preference, novel tank diving, and light-dark tests in order to evaluate subsequent rewarding, social, and emotional-like behavior. The combination of SR49059 and each drug progressively blocked: (1) rewarding behavior as measured by CPP in terms of time spent in drug-paired compartment; (2) prosocial effects measured on the basis of the time spent in the proximity of a nacre fish picture; and (3) anxiolytic effects in terms of the time spent in the upper half of the novel tank and in the white compartment of the tank used for the light-dark test. Antagonism was obtained at SR49059 doses which, when given alone, did not change motor function. In comparison with a control group, receiving vehicle alone, there was a three to five times increase in the brain release of isotocin (the analog of OT in fish) after treatment with the most active doses of MDMA (10 mg/kg), DOB (0.5 mg/kg), and PMA (0.1 mg/kg) as evaluated by means of bioanalytical reversed-phase high-performance liquid chromatography. Taken together, these findings show that the OT/vasopressin system is involved in the rewarding, prosocial, and anxiolytic effects of MDMA, DOB, and PMA in zebra fish and underline the association between this system and the behavioral alterations associated with disorders related to substance abuse.
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Affiliation(s)
| | - Daniela Braida
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, Milan, Italy
| | - Gianpietro Bondiolotti
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), Università degli Studi di Milano, Milan, Italy
| | - Mariaelvina Sala
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche (CNR), Milan, Italy
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Abstract
Oxytocin is a hypothalamic neuropeptide first recognized as a regulator of parturition and lactation which has recently gained attention for its ability to modulate social behaviors. In this chapter, we review several aspects of the oxytocinergic system, focusing on evidence for release of oxytocin and its receptor distribution in the cortex as the foundation for important networks that control social behavior. We examine the developmental timeline of the cortical oxytocin system as demonstrated by RNA, autoradiographic binding, and protein immunohistochemical studies, and describe how that might shape brain development and behavior. Many recent studies have implicated oxytocin in cognitive processes such as processing of sensory stimuli, social recognition, social memory, and fear. We review these studies and discuss the function of oxytocin in the young and adult cortex as a neuromodulator of central synaptic transmission and mediator of plasticity.
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53
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Bershad AK, Miller MA, Baggott MJ, de Wit H. The effects of MDMA on socio-emotional processing: Does MDMA differ from other stimulants? J Psychopharmacol 2016; 30:1248-1258. [PMID: 27562198 PMCID: PMC8753974 DOI: 10.1177/0269881116663120] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
±3,4-Methylenedioxymethamphetamine (MDMA) is a popular recreational drug that enhances sociability and feelings of closeness with others. These "prosocial" effects appear to motivate the recreational use of MDMA and may also form the basis of its potential as an adjunct to psychotherapy. However, the extent to which MDMA differs from prototypic stimulant drugs, such as dextroamphetamine, methamphetamine, and methylphenidate, in either its behavioral effects or mechanisms of action, is not fully known. The purpose of this review is to evaluate human laboratory findings of the social effects of MDMA compared to other stimulants, ranging from simple subjective ratings of sociability to more complex elements of social processing and behavior. We also review the neurochemical mechanisms by which these drugs may impact sociability. Together, the findings reviewed here lay the groundwork for better understanding the socially enhancing effects of MDMA that distinguish it from other stimulant drugs, especially as these effects relate to the reinforcing and potentially therapeutic effects of the drug.
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Affiliation(s)
- Anya K Bershad
- Department of Psychiatry and Behavioral Neuroscience,Interdisciplinary Scientist Training Program; University of Chicago, Chicago, IL, USA
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54
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MDMA (‘Ecstasy’), oxytocin and vasopressin modulate social preference in rats: A role for handling and oxytocin receptors. Pharmacol Biochem Behav 2016; 150-151:115-123. [DOI: 10.1016/j.pbb.2016.10.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 09/15/2016] [Accepted: 10/05/2016] [Indexed: 11/18/2022]
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55
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Lawson SK, Gray AC, Woehrle NS. Effects of oxytocin on serotonin 1B agonist-induced autism-like behavior in mice. Behav Brain Res 2016; 314:52-64. [DOI: 10.1016/j.bbr.2016.07.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 07/12/2016] [Accepted: 07/16/2016] [Indexed: 01/19/2023]
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Regional c-Fos expression induced by peripheral oxytocin administration is prevented by the vasopressin 1A receptor antagonist SR49059. Brain Res Bull 2016; 127:208-218. [PMID: 27725169 DOI: 10.1016/j.brainresbull.2016.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 10/05/2016] [Accepted: 10/06/2016] [Indexed: 12/18/2022]
Abstract
Peripherally administered oxytocin induces a wide range of behavioural and physiological effects that are thought to be mediated by the oxytocin receptor (OTR). However, oxytocin also has considerable affinity for the vasopressin 1A receptor (V1AR), such that various oxytocinergic effects may in fact be mediated by the V1AR rather than the OTR. Here we used c-Fos immunohistochemistry to determine the extent to which the regional pattern of neuronal activation produced by peripheral oxytocin involves the V1AR. Male Wistar rats were administered oxytocin (1mg/kg, IP) alone, or following pre-treatment with the V1AR antagonist SR49059 (1mg/kg, IP), and were assessed for locomotor activity changes and for c-Fos expression across a number of brain regions. Oxytocin reduced the distance travelled by rats during a 70min test session, and this inhibitory behavioural effect was prevented by SR49059. Consistent with previous reports, oxytocin increased c-Fos expression in a number of brain regions. In several of these regions-the supraoptic and paraventricular (PVN) nuclei of the hypothalamus, locus coeruleus and nucleus of the solitary tract-the c-Fos response was prevented by SR49059 pre-treatment. Notably, SR49059 inhibited the c-Fos activation in oxytocin-synthesising magnocellular neurons in the PVN. However, c-Fos expression in the central amygdala to oxytocin was unaffected by SR49059. The current findings add to an increasing body of research suggesting that many of the functional effects of oxytocin may be V1AR mediated.
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57
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Baracz SJ, Cornish JL. The neurocircuitry involved in oxytocin modulation of methamphetamine addiction. Front Neuroendocrinol 2016; 43:1-18. [PMID: 27546878 DOI: 10.1016/j.yfrne.2016.08.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/14/2016] [Accepted: 08/11/2016] [Indexed: 12/13/2022]
Abstract
The role of oxytocin in attenuating the abuse of licit and illicit drugs, including the psychostimulant methamphetamine, has been examined with increased ferocity in recent years. This is largely driven by the potential application of oxytocin as a pharmacotherapy. However, the neural mechanisms by which oxytocin modulates methamphetamine abuse are not well understood. Recent research identified an important role for the accumbens core and subthalamic nucleus in this process, which likely involves an interaction with dopamine, glutamate, GABA, and vasopressin. In addition to providing an overview of methamphetamine, the endogenous oxytocin system, and the effects of exogenous oxytocin on drug abuse, we propose a neural circuit through which exogenous oxytocin modulates methamphetamine abuse, focusing on its interaction with neurochemicals within the accumbens core and subthalamic nucleus. A growing understanding of exogenous oxytocin effects at a neurochemical and neurobiological level will assist in its evaluation as a pharmacotherapy for drug addiction.
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Affiliation(s)
- Sarah J Baracz
- School of Psychology, University of Sydney, Sydney, NSW 2109, Australia; Department of Psychology, Macquarie University, North Ryde, NSW 2109, Australia.
| | - Jennifer L Cornish
- Department of Psychology, Macquarie University, North Ryde, NSW 2109, Australia.
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58
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Duque-Wilckens N, Steinman MQ, Laredo SA, Hao R, Perkeybile AM, Bales KL, Trainor BC. Inhibition of vasopressin V1a receptors in the medioventral bed nucleus of the stria terminalis has sex- and context-specific anxiogenic effects. Neuropharmacology 2016; 110:59-68. [PMID: 27452721 DOI: 10.1016/j.neuropharm.2016.07.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/12/2016] [Accepted: 07/16/2016] [Indexed: 02/06/2023]
Abstract
Vasopressin V1a receptors (V1aR) are thought to contribute to the pathophysiology of psychiatric disorders such as anxiety and depression, sparking interest in V1aR as a therapeutic target. Although the global effects of V1aR have been documented, less is known about the specific neural circuits mediating these effects. Moreover, few studies have examined context-specific V1aR function in both males and females. By using the California mouse, we first studied the effects of sex and social defeat stress on V1aR binding in the forebrain. In females but not males, V1aR binding in the bed nucleus of the stria terminalis (BNST) was negatively correlated to social interaction behavior. In females stress also increased V1aR binding in the nucleus accumbens (NAc). Infusions of V1aR antagonist in to the medioventral BNST (BNSTmv) had anxiogenic effects only in animals naïve to defeat. For males, inhibition of V1aR in BNSTmv had anxiogenic effects in social and nonsocial contexts, but for females, anxiogenic effects were limited to social contexts. In stressed females, inhibition of V1aR in the NAc shell had no effect on social interaction behavior, but had an anxiogenic effect in an open field test. These data suggest that V1aR in BNSTmv have anxiolytic and prosocial effects in males, and that in females, prosocial and anxiolytic effects of V1aR appear to be mediated independently by receptors in the BNSTmv and NAc shell, respectively. These findings suggest that males have more overlap in neural circuits modulating anxiety in social and nonsocial contexts than females.
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Affiliation(s)
| | - Michael Q Steinman
- Molecular, Cellular, and Integrative Physiology Graduate Group, University of California, Davis, USA
| | - Sarah A Laredo
- Animal Behavior Graduate Group, University of California, Davis, USA
| | - Rebecca Hao
- Department of Psychology, University of California, Davis, USA
| | | | - Karen L Bales
- Animal Behavior Graduate Group, University of California, Davis, USA; Department of Psychology, University of California, Davis, USA
| | - Brian C Trainor
- Animal Behavior Graduate Group, University of California, Davis, USA; Department of Psychology, University of California, Davis, USA.
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59
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Moderate Stress-Induced Social Bonding and Oxytocin Signaling are Disrupted by Predator Odor in Male Rats. Neuropsychopharmacology 2016; 41:2160-70. [PMID: 26830961 PMCID: PMC4908646 DOI: 10.1038/npp.2016.16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 02/08/2023]
Abstract
In times of stress, social support can serve as a potent buffering mechanism that enhances resilience. In humans, stress can promote protective affiliative interactions and prosocial behavior. Yet, stress also precipitates psychopathologies characterized by social withdrawal such as post-traumatic stress disorder (PTSD) and depression. The factors that drive adaptive vs maladaptive social responses to stress are not yet clear. Rodent studies have focused on pair-bonded, opposite-sex mates and suggest that a variety of stressors can induce social support-like behaviors. However, between same-sex conspecifics-particularly males-stress effects on social bonding are less understood and often associated with aggression and social unrest. We thus sought to investigate if a moderate stressor-3 h of acute immobilization-impacts social-support behaviors differently when experienced in a neutral vs more innately threatening context (ie, paired with predator odor). We found that moderate stress increased social support-seeking behavior in rat cagemates and facilitated long-term sharing of a limited water resource, decreased aggression, and strongly defined dominance ranks (an indicator of home cage stability). In contrast, experiencing the same stressor in the presence of predator odor eliminated the positive behavioral effects of moderate stress. Importantly, hypothalamic oxytocin (OT) signaling increased coincident with stress in a neutral-but not a predator odor-context. Our results define a novel rodent model of divergent stress effects on social affiliation and OT signaling dependent on odor context with particularly strong relevance to stress-related disorders such as PTSD, which are characterized by a disrupted ability to seek and maintain social bonds.
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60
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Abstract
Lysergic acid diethylamide (LSD), described as a classical hallucinogen, began its journey from the middle of the last century following an accidental discovery. Since then, it was used as a popular and notorious substance of abuse in various parts of the world. Its beneficial role as an adjunct to psychotherapy was much unknown, until some 'benevolent' experiments were carried out over time to explore some of its potential uses. But, many of its effects were unclear and seemed to be a psychedelic enigma. In this review article, we have described the receptor pharmacology, mechanism of action, effects and adverse effects of LSD on the normal body system. We have also highlighted its addictive potentials and the chances of developing tolerance. We have assimilated some of the interesting therapeutic uses of this drug, such as an antianxiety agent, a creativity enhancer, a suggestibility enhancer, and a performance enhancer. We have also described LSD to be successfully used in drug and alcohol dependence, and as a part of psychedelic peak therapy in terminally ill patients. The relevant chronological history and literature in the light of present knowledge and scenarios have been discussed. Based on available evidence, LSD could be tried therapeutically in certain specific conditions under controlled settings. But as we mention, due to all the safety concerns, the use of this nonaddictive 'entheogen' in actual practice warrants a lot of expertise, caution, cooperation and ethical considerations.
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Affiliation(s)
- Saibal Das
- Department of Pharmacology, Christian Medical College, Vellore, 632002, India
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61
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Dumais KM, Alonso AG, Bredewold R, Veenema AH. Role of the oxytocin system in amygdala subregions in the regulation of social interest in male and female rats. Neuroscience 2016; 330:138-49. [PMID: 27235738 DOI: 10.1016/j.neuroscience.2016.05.036] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/13/2016] [Accepted: 05/16/2016] [Indexed: 01/13/2023]
Abstract
We previously found that oxytocin (OT) receptor (OTR) binding density in the medial amygdala (MeA) correlated positively with social interest (i.e., the motivation to investigate a conspecific) in male rats, while OTR binding density in the central amygdala (CeA) correlated negatively with social interest in female rats. Here, we determined the causal involvement of OTR in the MeA and CeA in the sex-specific regulation of social interest in adult rats by injecting an OTR antagonist (5ng/0.5μl/side) or OT (100pg/0.5μl/side) before the social interest test (4-min same-sex juvenile exposure). OTR blockade in the CeA decreased social interest in males but not females, while all other treatments had no behavioral effect. To further explore the sex-specific involvement of the OT system in the CeA in social interest, we used in vivo microdialysis to determine possible sex differences in endogenous OT release in the CeA during social interest. Interestingly, males and females showed similar levels of extracellular OT release at baseline and during social interest, suggesting that factors other than local OT release mediate the sex-specific role of CeA-OTR in social interest. Moreover, we found a positive correlation between CeA-OT release and social investigation time in females. This was further reflected by reduced CeA-OT release during social interest in females that expressed low compared to high social interest. We discuss the possibility that this reduction in OT release may be a consequence, rather than a cause, of exposure to a social stimulus. Overall, our findings show for the first time that extracellular OT release in the CeA is similar between males and females and that OTR in the CeA plays a causal role in the regulation of social interest toward juvenile conspecifics in males.
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Affiliation(s)
- Kelly M Dumais
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Avenue, 300 McGuinn, Chestnut Hill, MA 02467, USA.
| | - Andrea G Alonso
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Avenue, 300 McGuinn, Chestnut Hill, MA 02467, USA
| | - Remco Bredewold
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Avenue, 300 McGuinn, Chestnut Hill, MA 02467, USA
| | - Alexa H Veenema
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Avenue, 300 McGuinn, Chestnut Hill, MA 02467, USA
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62
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Song Z, Larkin TE, Malley MO, Albers HE. Oxytocin (OT) and arginine-vasopressin (AVP) act on OT receptors and not AVP V1a receptors to enhance social recognition in adult Syrian hamsters (Mesocricetus auratus). Horm Behav 2016; 81:20-7. [PMID: 26975586 DOI: 10.1016/j.yhbeh.2016.02.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 01/24/2016] [Accepted: 02/05/2016] [Indexed: 11/20/2022]
Abstract
Social recognition is a fundamental requirement for all forms of social relationships. A majority of studies investigating the neural mechanisms underlying social recognition in rodents have investigated relatively neutral social stimuli such as juveniles or ovariectomized females over short time intervals (e.g., 2h). The present study developed a new testing model to study social recognition among adult males using a potent social stimulus. Flank gland odors are used extensively in social communication in Syrian hamsters and convey important information such as dominance status. We found that the recognition of flank gland odors after a 3min exposure lasted for at least 24h, substantially longer than the recognition of other social cues in rats and mice. Intracerebroventricular injections of OT and AVP prolonged the recognition of flank gland odor for up to 48h. Selective OTR but not V1aR agonists, mimicked these enhancing effects of OT and AVP. Similarly, selective OTR but not V1aR antagonists blocked recognition of the odors after 20min. In contrast, the recognition of non-social stimuli was not blocked by either the OTR or the V1aR antagonists. Our findings suggest both OT and AVP enhance social recognition via acting on OTRs and not V1aRs and that the recognition enhancing effects of OT and AVP are limited to social stimuli.
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Affiliation(s)
- Zhimin Song
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - Tony E Larkin
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - Maureen O' Malley
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - H Elliott Albers
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA.
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63
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Tamborski S, Mintz EM, Caldwell HK. Sex Differences in the Embryonic Development of the Central Oxytocin System in Mice. J Neuroendocrinol 2016; 28. [PMID: 26763721 DOI: 10.1111/jne.12364] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 12/28/2022]
Abstract
Recent studies suggest that oxytocin (OXT) may be important for organising the neural circuitry that underlies adult social behaviour. Although most of the work exploring these effects has focused on early postnatal development, there is evidence that OXT may also be important during foetal development. However, without an understanding of how the OXT system develops, the ability to functionally link OXT in foetal life to adult behaviour is limited. To understand where and when OXT could be acting during embryonic development to affect the organisation of neural substrates, we examined the development of the mouse OXT system from embryonic day (E) 12.5 through postnatal day (PND) 2 using OXT receptor (OXTR) binding and a quantitative polymerase chain reaction. In both males and females, OXTR binding was observed by E16.5 in the ventricular and subventricular zones, as well as the developing amygdala. In males, OXT mRNA was not detectable until PND2, whereas it was detectable by E16.5 in females. OXTR mRNA was detected by E12.5 in both sexes, although females appear to have more OXTR mRNA during foetal development than males. The present study is significant because it is the first to reveal an unexpected sex difference in the development of the OXT system and supports the possibility that OXT during foetal development may contribute to sex differences in adult behaviour.
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Affiliation(s)
- S Tamborski
- Laboratory of Neuroendocrinology and Behavior, Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - E M Mintz
- Department of Biological Sciences, Kent State University, Kent, OH, USA
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - H K Caldwell
- Laboratory of Neuroendocrinology and Behavior, Department of Biological Sciences, Kent State University, Kent, OH, USA
- School of Biomedical Sciences, Kent State University, Kent, OH, USA
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64
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Kent P, Awadia A, Zhao L, Ensan D, Silva D, Cayer C, James JS, Anisman H, Merali Z. Effects of intranasal and peripheral oxytocin or gastrin-releasing peptide administration on social interaction and corticosterone levels in rats. Psychoneuroendocrinology 2016; 64:123-30. [PMID: 26658172 DOI: 10.1016/j.psyneuen.2015.11.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/17/2015] [Accepted: 11/20/2015] [Indexed: 12/13/2022]
Abstract
The intranasal route of drug administration has gained increased popularity as it is thought to allow large molecules, such as peptide hormones, more direct access to the brain, while limiting systemic exposure. Several studies have investigated the effects of intranasal oxytocin administration in humans as this peptide is associated with prosocial behavior. There are, however, few preclinical studies investigating the effects of intranasal oxytocin administration in rodents. Oxytocin modulates hypothalamic-pituitary-adrenal (HPA) axis functioning and it has been suggested that oxytocin's ability to increase sociability may occur through a reduction in stress reactivity. Another peptide that appears to influence both social behavior and HPA axis activity is gastrin-releasing peptide (GRP), but it is not known if these GRP-induced effects are related. With this in mind, in the present study, we assessed the effects of intranasal and intraperitoneal oxytocin and GRP administration on social interaction and release of corticosterone in rats. Intranasal and intraperitoneal administration of 20, but not 5 μg, of oxytocin significantly increased social interaction, whereas intranasal and peripheral administration of GRP (20 but not 5 μg) significantly decreased levels of social interaction. In addition, while intranasal oxytocin (20 μg) had no effect on blood corticosterone levels, a marked increase in blood corticosterone levels was observed following intraperitoneal oxytocin administration. With GRP, intranasal (20 μg) but not peripheral administration increased corticosterone levels. These findings provide further evidence that intranasal peptide delivery can induce behavioral alterations in rodents which is consistent with findings from human studies. In addition, the peptide-induced changes in social interaction were not linked to fluctuations in corticosterone levels.
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Affiliation(s)
- Pamela Kent
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Alisha Awadia
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Leah Zhao
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada
| | - Donna Ensan
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Dinuka Silva
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Christian Cayer
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Jonathan S James
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Hymie Anisman
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Zul Merali
- University of Ottawa Institute of Mental Health Research, 1145 Carling Avenue, Ottawa, ON K1Z 7K4, Canada; Department of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Department of Psychiatry, University of Ottawa, Ottawa, ON K1N 6N5, Canada; Institute of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada.
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65
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Dumais KM, Alonso AG, Immormino MA, Bredewold R, Veenema AH. Involvement of the oxytocin system in the bed nucleus of the stria terminalis in the sex-specific regulation of social recognition. Psychoneuroendocrinology 2016; 64:79-88. [PMID: 26630388 PMCID: PMC4698213 DOI: 10.1016/j.psyneuen.2015.11.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/08/2015] [Accepted: 11/08/2015] [Indexed: 01/03/2023]
Abstract
Sex differences in the oxytocin (OT) system in the brain may explain why OT often regulates social behaviors in sex-specific ways. However, a link between sex differences in the OT system and sex-specific regulation of social behavior has not been tested. Here, we determined whether sex differences in the OT receptor (OTR) or in OT release in the posterior bed nucleus of the stria terminalis (pBNST) mediates sex-specific regulation of social recognition in rats. We recently showed that, compared to female rats, male rats have a three-fold higher OTR binding density in the pBNST, a sexually dimorphic area implicated in the regulation of social behaviors. We now demonstrate that OTR antagonist (5 ng/0.5 μl/side) administration into the pBNST impairs social recognition in both sexes, while OT (100 pg/0.5 μl/side) administration into the pBNST prolongs the duration of social recognition in males only. These effects seem specific to social recognition, as neither treatment altered total social investigation time in either sex. Moreover, baseline OT release in the pBNST, as measured with in vivo microdialysis, did not differ between the sexes. However, males showed higher OT release in the pBNST during social recognition compared to females. These findings suggest a sex-specific role of the OT system in the pBNST in the regulation of social recognition.
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Affiliation(s)
- Kelly M. Dumais
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA,Corresponding author: Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, McGuinn 300, Chestnut Hill, MA, 02467, USA, , 617-552-6149
| | - Andrea G. Alonso
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA
| | - Marisa A. Immormino
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA
| | - Remco Bredewold
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA
| | - Alexa H. Veenema
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA
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Empathic accuracy and oxytocin after tryptophan depletion in adults at risk for depression. Psychopharmacology (Berl) 2016; 233:111-20. [PMID: 26462806 PMCID: PMC4700075 DOI: 10.1007/s00213-015-4093-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 09/21/2015] [Indexed: 01/10/2023]
Abstract
RATIONALE Major depressive disorder (MDD) has been associated with disturbances in social functioning and in the brain serotonin system. Reduced levels of serotonin may negatively influence social functioning, for example by impairing the recognition of facial emotion expressions. OBJECTIVES The present study investigated the effect of acute tryptophan depletion (ATD), which reduces brain serotonin, on a related component of social functioning, empathic accuracy (EA), and oxytocin levels. METHODS Individuals with (FH+) and without (FH−) a family history of MDD participated in a randomized, double-blind, crossover study. On two separate test days, participants ingested tryptophan-deficient and nutritionally balanced amino acid mixtures. Six hours later, they performed an EA task, which involved watching videos of people recounting autobiographical emotional events. While watching, participants continuously rated how these people felt during the recounting. Mood state was repeatedly assessed using the Positive Affect and Negative Affect Schedule and a series of visual analogue scales. Blood samples obtained at baseline and 5 h after mixture ingestion were assessed for tryptophan and oxytocin levels. RESULTS ATD decreased circulating levels of tryptophan and oxytocin. Nevertheless, there were no significant effects of ATD on EA or mood in either FH group. CONCLUSIONS While previous studies have shown that acute reductions in brain serotonin alter the recognition of facial emotion expressions in never-depressed individuals, the present study suggests that empathic abilities may remain unaffected.
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Lee SY, Lee AR, Hwangbo R, Han J, Hong M, Bahn GH. Is Oxytocin Application for Autism Spectrum Disorder Evidence-Based? Exp Neurobiol 2015; 24:312-24. [PMID: 26713079 PMCID: PMC4688331 DOI: 10.5607/en.2015.24.4.312] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 11/25/2015] [Accepted: 11/25/2015] [Indexed: 01/06/2023] Open
Abstract
Autism spectrum disorder (ASD) is characterized by persistent deficits within two core symptom domains: social communication and restricted, repetitive behaviors. Although numerous studies have reported psychopharmacological treatment outcomes for the core symptom domains of ASD, there are not enough studies on fundamental treatments based on the etiological pathology of ASD. Studies on candidate medications related to the pathogenesis of ASD, such as naltrexone and secretin, were conducted, but the results were inconclusive. Oxytocin has been identified as having an important role in maternal behavior and attachment, and it has been recognized as a key factor in the social developmental deficit seen in ASD. Genetic studies have also identified associations between ASD and the oxytocin pathway. As ASD has its onset in infancy, parents are willing to try even experimental or unapproved treatments in an effort to avoid missing the critical period for diagnosis and treatment, which can place their child in an irreversible state. While therapeutic application of oxytocin for ASD is in its early stages, we have concluded that oxytocin would be a promising therapeutic substance via a thorough literature review focusing on the following: the relationship between oxytocin and sociality; single nucleotide polymorphisms as a biological marker of ASD; and validity verification of oxytocin treatment in humans. We also reviewed materials related to the mechanism of oxytocin action that may support its potential application in treating ASD.
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Affiliation(s)
- Seung Yup Lee
- Graduate School of Medicine, Kyung Hee University, Seoul 02543, Korea
| | - Ah Rah Lee
- Kyung Hee University School of Medicine, Seoul 02543, Korea
| | - Ram Hwangbo
- Department of Psychiatry, Kyung Hee University Hospital, Seoul 02447, Korea
| | - Juhee Han
- Department of Psychiatry, Kyung Hee University Hospital, Seoul 02447, Korea
| | - Minha Hong
- Department of Psychiatry, Seonam University, College of Medicine, Myongji Hospital, Goyang 10475, Korea
| | - Geon Ho Bahn
- Department of Psychiatry, Kyung Hee University School of Medicine, Seoul 02447, Korea
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Amoroso T. The Psychopharmacology of ±3,4 Methylenedioxymethamphetamine and its Role in the Treatment of Posttraumatic Stress Disorder. J Psychoactive Drugs 2015; 47:337-44. [DOI: 10.1080/02791072.2015.1094156] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Finkenwirth C, van Schaik C, Ziegler TE, Burkart JM. Strongly bonded family members in common marmosets show synchronized fluctuations in oxytocin. Physiol Behav 2015; 151:246-51. [PMID: 26232089 PMCID: PMC5916785 DOI: 10.1016/j.physbeh.2015.07.034] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/23/2015] [Accepted: 07/27/2015] [Indexed: 11/16/2022]
Abstract
Oxytocin is a key regulator of social bonding and is positively linked to affiliation and prosocial behavior in several mammal species. In chimpanzees, this link is dyad-specific as affiliative interactions only elicit high oxytocin release if they involve strongly bonded individuals. These studies involved isolated dyads and sampling events. Little is known about the role of oxytocin in affiliation and social bonding, and about potential long-term patterns of bonding-related and dyad-specific oxytocin effects within highly affiliative and cooperative social groups. Our aim was to investigate whether bonding-related oxytocin signatures linked to dyadic affiliation are present in family groups of cooperatively breeding marmoset monkeys (Callithrix jacchus) that show high levels of cohesion and cooperation. In 30 dyads from four family groups and one pair, we measured urinary baseline oxytocin over six weeks and analyzed the link to bond strength (mean dyadic affiliation). Strongly bonded dyads showed synchronized longitudinal fluctuations of oxytocin, indicating that dyad-specific oxytocin effects can also be traced in the group context and in an interdependent species. We discuss these results in light of the potential function of differentiated relationships between marmoset dyads other than the breeding pair, and the role of oxytocin as a mediator for social bonding.
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Affiliation(s)
- Christa Finkenwirth
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
| | - Carel van Schaik
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Toni E Ziegler
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, WI 53715, USA
| | - Judith M Burkart
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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Acute Effects of Lysergic Acid Diethylamide in Healthy Subjects. Biol Psychiatry 2015; 78:544-53. [PMID: 25575620 DOI: 10.1016/j.biopsych.2014.11.015] [Citation(s) in RCA: 258] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 10/28/2014] [Accepted: 11/11/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND After no research in humans for >40 years, there is renewed interest in using lysergic acid diethylamide (LSD) in clinical psychiatric research and practice. There are no modern studies on the subjective and autonomic effects of LSD, and its endocrine effects are unknown. In animals, LSD disrupts prepulse inhibition (PPI) of the acoustic startle response, and patients with schizophrenia exhibit similar impairments in PPI. However, no data are available on the effects of LSD on PPI in humans. METHODS In a double-blind, randomized, placebo-controlled, crossover study, LSD (200 μg) and placebo were administered to 16 healthy subjects (8 women, 8 men). Outcome measures included psychometric scales; investigator ratings; PPI of the acoustic startle response; and autonomic, endocrine, and adverse effects. RESULTS Administration of LSD to healthy subjects produced pronounced alterations in waking consciousness that lasted 12 hours. The predominant effects induced by LSD included visual hallucinations, audiovisual synesthesia, and positively experienced derealization and depersonalization phenomena. Subjective well-being, happiness, closeness to others, openness, and trust were increased by LSD. Compared with placebo, LSD decreased PPI. LSD significantly increased blood pressure, heart rate, body temperature, pupil size, plasma cortisol, prolactin, oxytocin, and epinephrine. Adverse effects produced by LSD completely subsided within 72 hours. No severe acute adverse effects were observed. CONCLUSIONS In addition to marked hallucinogenic effects, LSD exerts methylenedioxymethamphetamine-like empathogenic mood effects that may be useful in psychotherapy. LSD altered sensorimotor gating in a human model of psychosis, supporting the use of LSD in translational psychiatric research. In a controlled clinical setting, LSD can be used safely, but it produces significant sympathomimetic stimulation.
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Kamilar-Britt P, Bedi G. The prosocial effects of 3,4-methylenedioxymethamphetamine (MDMA): Controlled studies in humans and laboratory animals. Neurosci Biobehav Rev 2015; 57:433-46. [PMID: 26408071 DOI: 10.1016/j.neubiorev.2015.08.016] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 08/26/2015] [Accepted: 08/28/2015] [Indexed: 02/03/2023]
Abstract
Users of ±3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') report prosocial effects such as sociability and empathy. Supporting these apparently unique social effects, data from controlled laboratory studies indicate that MDMA alters social feelings, information processing, and behavior in humans, and social behavior in rodents. Here, we review this growing body of evidence. In rodents, MDMA increases passive prosocial behavior (adjacent lying) and social reward while decreasing aggression, effects that may involve serotonin 1A receptor mediated oxytocin release interacting with vasopressin receptor 1A. In humans, MDMA increases plasma oxytocin and produces feelings of social affiliation. It decreases identification of negative facial expressions (cognitive empathy) and blunts responses to social rejection, while enhancing responses to others' positive emotions (emotional empathy) and increasing social approach. Thus, consistent with drug folklore, laboratory administration of MDMA robustly alters social processing in humans and increases social approach in humans and animals. Effects are consistent with increased sociability, with mixed evidence about enhanced empathy. These neurobiologically-complex prosocial effects likely motivate recreational ecstasy use.
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Affiliation(s)
- Philip Kamilar-Britt
- Division on Substance Abuse, New York State Psychiatric Institute, 1051 Riverside Drive, MC 120, New York, NY 10032, United States.
| | - Gillinder Bedi
- Division on Substance Abuse, New York State Psychiatric Institute, Department of Psychiatry, College of Physicians and Surgeons of Columbia University, 1051 Riverside Drive, MC 120, New York, NY 10032, United States.
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Ferris CF, Yee JR, Kenkel WM, Dumais KM, Moore K, Veenema AH, Kulkarni P, Perkybile AM, Carter CS. Distinct BOLD Activation Profiles Following Central and Peripheral Oxytocin Administration in Awake Rats. Front Behav Neurosci 2015; 9:245. [PMID: 26441574 PMCID: PMC4585275 DOI: 10.3389/fnbeh.2015.00245] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 08/24/2015] [Indexed: 11/13/2022] Open
Abstract
A growing body of literature has suggested that intranasal oxytocin (OT) or other systemic routes of administration can alter prosocial behavior, presumably by directly activating OT sensitive neural circuits in the brain. Yet there is no clear evidence that OT given peripherally can cross the blood-brain barrier at levels sufficient to engage the OT receptor. To address this issue we examined changes in blood oxygen level-dependent (BOLD) signal intensity in response to peripheral OT injections (0.1, 0.5, or 2.5 mg/kg) during functional magnetic resonance imaging (fMRI) in awake rats imaged at 7.0 T. These data were compared to OT (1 μg/5 μl) given directly to the brain via the lateral cerebroventricle. Using a 3D annotated MRI atlas of the rat brain segmented into 171 brain areas and computational analysis, we reconstructed the distributed integrated neural circuits identified with BOLD fMRI following central and peripheral OT. Both routes of administration caused significant changes in BOLD signal within the first 10 min of administration. As expected, central OT activated a majority of brain areas known to express a high density of OT receptors, e.g., lateral septum, subiculum, shell of the accumbens, bed nucleus of the stria terminalis. This profile of activation was not matched by peripheral OT. The change in BOLD signal to peripheral OT did not show any discernible dose-response. Interestingly, peripheral OT affected all subdivisions of the olfactory bulb, in addition to the cerebellum and several brainstem areas relevant to the autonomic nervous system, including the solitary tract nucleus. The results from this imaging study do not support a direct central action of peripheral OT on the brain. Instead, the patterns of brain activity suggest that peripheral OT may interact at the level of the olfactory bulb and through sensory afferents from the autonomic nervous system to influence brain activity.
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Affiliation(s)
- Craig F Ferris
- Center for Translational NeuroImaging, Northeastern University , Boston, MA , USA
| | - Jason R Yee
- Center for Translational NeuroImaging, Northeastern University , Boston, MA , USA ; Kinsey Institute, Indiana University , Bloomington, IN , USA
| | | | - Kelly Marie Dumais
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College , Chestnut Hill, MA , USA
| | - Kelsey Moore
- Center for Translational NeuroImaging, Northeastern University , Boston, MA , USA
| | - Alexa H Veenema
- Neurobiology of Social Behavior Laboratory, Department of Psychology, Boston College , Chestnut Hill, MA , USA
| | - Praveen Kulkarni
- Center for Translational NeuroImaging, Northeastern University , Boston, MA , USA
| | | | - C Sue Carter
- Kinsey Institute, Indiana University , Bloomington, IN , USA
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Blanco-Gandía MC, Mateos-García A, García-Pardo MP, Montagud-Romero S, Rodríguez-Arias M, Miñarro J, Aguilar MA. Effect of drugs of abuse on social behaviour. Behav Pharmacol 2015. [DOI: 10.1097/fbp.0000000000000162] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Baracz SJ, Everett NA, Cornish JL. The Involvement of Oxytocin in the Subthalamic Nucleus on Relapse to Methamphetamine-Seeking Behaviour. PLoS One 2015; 10:e0136132. [PMID: 26284529 PMCID: PMC4540453 DOI: 10.1371/journal.pone.0136132] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 07/31/2015] [Indexed: 12/11/2022] Open
Abstract
The psychostimulant methamphetamine (METH) is an addictive drug of abuse. The neuropeptide oxytocin has been shown to modulate METH-related reward and METH-seeking behaviour. Recent findings implicated the subthalamic nucleus (STh) as a key brain region in oxytocin modulation of METH-induced reward. However, it is unclear if oxytocin acts in this region to attenuate relapse to METH-seeking behaviour, and if this action is through the oxytocin receptor. We aimed to determine whether oxytocin pretreatment administered into the STh would reduce reinstatement to METH use in rats experienced at METH self-administration, and if this could be reversed by the co-administration of the oxytocin receptor antagonist desGly-NH2,d(CH2)5[D-Tyr2,Thr4]OVT. Male Sprague Dawley rats underwent surgery to implant an intravenous jugular vein catheter and bilateral microinjection cannulae into the STh under isoflourane anaesthesia. Rats were then trained to self-administer intravenous METH (0.1 mg/kg/infusion) by lever press during 2-hour sessions under a fixed ratio 1 schedule for 20 days. Following extinction of lever press activity, the effect of microinjecting saline, oxytocin (0.2 pmol, 0.6 pmol, 1.8 pmol, 3.6 pmol) or co-administration of oxytocin (3.6 pmol) and desGly-NH2,d(CH2)5[D-Tyr2,Thr4]OVT (3 nmol) into the STh (200 nl/side) was examined on METH-primed reinstatement (1 mg/kg; i.p.). We found that local administration of the highest oxytocin dose (3.6 pmol) into the STh decreased METH-induced reinstatement and desGly-NH2,d(CH2)5[D-Tyr2,Thr4]OVT had a non-specific effect on lever press activity. These findings highlight that oxytocin modulation of the STh is an important modulator of relapse to METH abuse.
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Affiliation(s)
- Sarah Jane Baracz
- Department of Psychology, Macquarie University, Sydney, Australia, 2109
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WAY 267,464, a non-peptide oxytocin receptor agonist, impairs social recognition memory in rats through a vasopressin 1A receptor antagonist action. Psychopharmacology (Berl) 2015; 232:2659-67. [PMID: 25761839 DOI: 10.1007/s00213-015-3902-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 02/23/2015] [Indexed: 01/02/2023]
Abstract
RATIONALE Recent in vitro studies suggest that the oxytocin receptor (OTR) agonist WAY 267,464 has vasopressin 1A receptor (V1AR) antagonist effects. This might limit its therapeutic potential due to the positive involvement of the V1AR in social behavior. OBJECTIVES The objective of this study was to assess functional V1AR antagonist-like effects of WAY 267,464 in vivo using a test of social recognition memory. METHODS Adult experimental rats were tested for their recognition of a juvenile conspecific rat that they had briefly met 30 or 120 min previously. The modulatory effects of vasopressin (AVP), the selective V1AR antagonist SR49059, and WAY 267,464 were examined together with those of the selective OTR antagonist Compound 25 (C25). Drugs were administered immediately after the first meeting. RESULTS Control rats showed recognition of juveniles at a 30 min, but not a 120 min retention interval. AVP (0.005, but not 0.001 mg/kg intraperitoneal (i.p.)) improved memory such that recognition was evident after 120 min. This was prevented by pretreatment with SR49059 (1 mg/kg) and WAY 267,464 (10, 30, and 100 mg/kg). Given alone, SR49059 (1 mg/kg) and WAY 267,464 (30 and 100 mg/kg) impaired memory at a 30 min retention interval. The impairment with WAY 267,464 was not prevented by C25 (5 mg/kg), suggesting V1AR rather than OTR mediation of the effect. Given alone, C25 also impaired memory. CONCLUSIONS These results highlight a tonic role for endogenous AVP (and oxytocin) in social recognition memory and indicate that WAY 267,464 functions in vivo as a V1AR antagonist to prevent the memory-enhancing effects of AVP.
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Oxytocin and MDMA ('Ecstasy') enhance social reward in rats. Psychopharmacology (Berl) 2015; 232:2631-41. [PMID: 25772337 DOI: 10.1007/s00213-015-3899-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 02/16/2015] [Indexed: 01/05/2023]
Abstract
RATIONALE Oxytocin (OT), vasopressin (AVP) and 3,4 methylenedioxymethamphetamine (MDMA, 'Ecstasy') all increase social interaction in rats, perhaps by enhancing the rewarding value of social encounters. OBJECTIVES Here, we used the conditioned place preference (CPP) paradigm to assess the intrinsic rewarding effects of OT, AVP and MDMA, and whether these effects are enhanced by the presence of a conspecific, or a dynamic, tactile object (a tennis ball). METHODS Adult male rats received conditioning sessions in a CPP apparatus twice a day (vehicle at 10 a.m., drug at 3 p.m.). Experiment 1 involved conditioning with OT (0.5 mg/kg, intraperitoneal (i.p.)), AVP (0.005 mg/kg, i.p.) or MDMA (5 mg/kg, i.p.). Experiments 2 and 3 involved conditioning with the same treatments but in the presence of a conspecific receiving the same treatment (social-CPP) or in the presence of a tennis ball (object-CPP), respectively. Conditioned place preference was assessed 24 h, 2 weeks and 4 weeks later. RESULTS OT, AVP and MDMA did not produce a conventional CPP. However, when the conditioning environment also contained a conspecific both OT and MDMA induced a significant CPP lasting for at least 4 weeks. Rats given OT and MDMA also developed a more modest yet significant CPP for the environment where they encountered a tennis ball. CONCLUSIONS These results indicate that OT and MDMA can augment the rewarding effects of social interaction, but also interaction with a dynamic and tactile non-social object. AVP does not condition social- or object-CPPs and may promote social proximity by inducing generalized anxiety and defensive aggregation.
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Lukas M, Wöhr M. Endogenous vasopressin, innate anxiety, and the emission of pro-social 50-kHz ultrasonic vocalizations during social play behavior in juvenile rats. Psychoneuroendocrinology 2015; 56:35-44. [PMID: 25800147 DOI: 10.1016/j.psyneuen.2015.03.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 01/28/2015] [Accepted: 03/03/2015] [Indexed: 12/17/2022]
Abstract
Although the involvement of the neuropeptide arginine vasopressin (AVP) in rodent social interaction is already extensively characterized, little is known about its role in social communication. Rats communicate in the ultrasonic range by means of ultrasonic vocalizations (USV). Depending on developmental stage and affective state, rats emit various distinct types of USV, with appetitive 50-kHz USV being induced by positive social interactions, like juvenile social play, probably serving an affiliative communicative function, namely to (re)establish or induce social proximity. In rats and mice selectively bred for low (LAB) and high (HAB) anxiety-related behavior, the emission of isolation-induced distress USV during maternal deprivation as pups correlates with innate high levels of hypothalamic AVP availability. Moreover, male LAB and HAB rats express deficits in social approach towards conspecifics, together with high and/or abnormal forms of aggression when confronted with harmless opponents, possibly due to a lack of social communication skills. The aim of this study was therefore (1) to investigate and characterize social play behavior and concomitant pro-social 50-kHz USV emission in male and female, juvenile LAB and HAB rats and to compare them to non-selected Wistar (NAB) rats; and (2) to link these findings pharmacologically to the central AVP system via applying an AVP 1a receptor (V1aR) antagonist (0.75 μg; Manning compound) or synthetic AVP (1 ng) into the lateral ventricle of male juvenile NAB rats. Our results show that reduced social play behavior in highly anxious male and female, juvenile HAB rats is accompanied by low amounts of pro-social 50-kHz USV, as compared to respective LAB and NAB rats, possibly reflecting a lack of positive affective states in expectation of or following social interactions in these individuals. Secondly, although synthetic AVP did not alter social play behavior and pro-social 50-kHz USV, we demonstrated for the first time that a blockade of the central AVP system not only reduces juvenile social play behavior, but at the same time pro-social 50-kHz USV emission rates, indicating an involvement of the social neuropeptide in regulating affiliative communication in rodents.
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Affiliation(s)
- Michael Lukas
- Behavioral and Molecular Neurobiology, Faculty of Biology, University of Regensburg, 93053 Regensburg, Germany.
| | - Markus Wöhr
- Behavioral Neuroscience, Faculty of Psychology, Philipps-University of Marburg, 35032 Marburg, Germany.
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Abstract
PURPOSE OF REVIEW To provide a review of the recent advances in the diagnosis and treatment of psychiatric disorders in Prader-Willi syndrome (PWS). RECENT FINDINGS Research in the last 12 months has provided a descriptive prognosis of psychosis in PWS and highlighted the possible genes associated with the increased risk of psychosis for those with maternal uniparental disomy (mUPD). Several studies investigating social and communication skills have shown people with PWS to have difficulty with core, receptive and expressive language skills, interpreting emotional valence in faces, playing with children of their own age, understanding personal space and a developmental delay in the theory of mind. These social and communication deficits are often more pronounced in those with mUPD. Two recent clinical trials of oxytocin provide mixed results and highlight the need for an improved understanding of the neurobiological characteristics of the PWS brain. A recent pilot study suggests N-acetylcysteine may be a viable treatment for skin picking. SUMMARY Recent advances have contributed to our understanding of the emotional and behavioural problems associated with PWS, and provided directions for further research.
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Abstract
RATIONALE The drug ±3,4-methylenedioxymethamphetamine (MDMA, "ecstasy," "molly") is thought to produce prosocial effects and enhance social interaction. However, in most laboratory studies to date, the participants have been tested under nonsocial conditions, which may not simulate the effects the drug produces in more naturalistic social settings. METHODS Healthy experienced MDMA users participated in three laboratory sessions in which they received MDMA (0.5 or 1.0 mg/kg or placebo, double blind). They were randomly assigned to one of three social conditions, in which they were tested alone (solitary (SOL); N = 10), in the presence of a research assistant (research assistant present (RAP); N = 11) or in the presence of another participant who also received the drug (other participant present (OPP); N = 11). RESULTS As expected, MDMA increased heart rate and blood pressure and produced positive subjective effects in all the three groups. It also increased ratings of attractiveness of another person and increased social interaction in RAP and OPP. The social context affected certain responses to the drug. The effects of MDMA were greater in the OPP condition, compared to the SOL or RAP conditions, on measures of "feel drug," "dizzy," and on cardiovascular. But responses to the drug on other measures, including social behavior, did not differ across the conditions. CONCLUSIONS These findings provide some support for the idea that drugs produce greater effects when they are used in the presence of other drug users. However, the influence of the social context was modest, and it remains to be determined whether other variables related to social context would substantially alter the effects of MDMA or other drugs.
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Holley A, Bellevue S, Vosberg D, Wenzel K, Roorda S, Pfaus JG. The role of oxytocin and vasopressin in conditioned mate guarding behavior in the female rat. Physiol Behav 2015; 144:7-14. [PMID: 25724299 DOI: 10.1016/j.physbeh.2015.02.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 02/07/2015] [Accepted: 02/23/2015] [Indexed: 10/23/2022]
Abstract
We have shown previously that female rats given their first copulatory experiences with the same male rat display mate guarding behavior in the presence of that male provided a female competitor is also present. Females given access to the familiar male show more Fos induction within regions of the brain that contain oxytocin (OT) and vasopressin (AVP) cell bodies, notably the supraoptic (SON) and paraventricular nuclei (PVN) relative to females given sexual experience with different males. The present experiments examined whether the Fos induction we previously observed within the SON and PVN occurred within OT and/or AVP neurons, and whether exogenous administration of OT or AVP prior to female rats first sexual experience could potentiate the acquisition of mate guarding behavior. Female rats that display conditioned mate guarding had significantly more double-labeled Fos/OT neurons in both SON and PVN, and significantly more Fos/AVP neurons in the PVN. Peripheral administration of OT or AVP prior to their first sexual experience with the familiar male facilitated different aspects of mate guarding: OT augmented affiliative behaviors and presenting responses whereas AVP augmented interference behavior. These results indicate that female rats' first experiences with sexual reward when paired with the same male induce changes to bonding networks in the brain. Moreover peripheral administration of OT or AVP during their first sexual experience can augment different aspects of mate guarding behavior.
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Affiliation(s)
- Amanda Holley
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada.
| | - Shannon Bellevue
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada
| | - Daniel Vosberg
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada
| | - Kerstin Wenzel
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada
| | - Sieger Roorda
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada
| | - James G Pfaus
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, QC H4B 1R6 Canada
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81
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Oxytocin prevents ethanol actions at δ subunit-containing GABAA receptors and attenuates ethanol-induced motor impairment in rats. Proc Natl Acad Sci U S A 2015; 112:3104-9. [PMID: 25713389 DOI: 10.1073/pnas.1416900112] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Even moderate doses of alcohol cause considerable impairment of motor coordination, an effect that substantially involves potentiation of GABAergic activity at δ subunit-containing GABA(A) receptors (δ-GABA(A)Rs). Here, we demonstrate that oxytocin selectively attenuates ethanol-induced motor impairment and ethanol-induced increases in GABAergic activity at δ-GABA(A)Rs and that this effect does not involve the oxytocin receptor. Specifically, oxytocin (1 µg i.c.v.) given before ethanol (1.5 g/kg i.p.) attenuated the sedation and ataxia induced by ethanol in the open-field locomotor test, wire-hanging test, and righting-reflex test in male rats. Using two-electrode voltage-clamp electrophysiology in Xenopus oocytes, oxytocin was found to completely block ethanol-enhanced activity at α4β1δ and α4β3δ recombinant GABA(A)Rs. Conversely, ethanol had no effect when applied to α4β1 or α4β3 cells, demonstrating the critical presence of the δ subunit in this effect. Oxytocin had no effect on the motor impairment or in vitro effects induced by the δ-selective GABA(A)R agonist 4,5,6,7-tetrahydroisoxazolo(5,4-c)pyridin-3-ol, which binds at a different site on δ-GABA(A)Rs than ethanol. Vasopressin, which is a nonapeptide with substantial structural similarity to oxytocin, did not alter ethanol effects at δ-GABA(A)Rs. This pattern of results confirms the specificity of the interaction between oxytocin and ethanol at δ-GABA(A)Rs. Finally, our in vitro constructs did not express any oxytocin receptors, meaning that the observed interactions occur directly at δ-GABA(A)Rs. The profound and direct interaction observed between oxytocin and ethanol at the behavioral and cellular level may have relevance for the development of novel therapeutics for alcohol intoxication and dependence.
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82
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Lukas M, de Jong TR. Conspecific Interactions in Adult Laboratory Rodents: Friends or Foes? Curr Top Behav Neurosci 2015; 30:3-24. [PMID: 27240675 DOI: 10.1007/7854_2015_428] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Interactions between adult conspecifics, including sexual behaviors, affiliation, and aggression are crucial for the well-being, survival, and reproduction of mammals. This holds true for any mammalian species, but certainly for humans: An inability to optimally navigate the social system can have a strong negative impact on physical and mental health. Translational rodent models have been used for decades to unravel the neural pathways and substrates involved in normal and abnormal conspecific interactions. Researchers in the field of translational social neuroscience face a double challenge: Not only do they need to pay considerable attention to the behavioral ecology of their model species or their ancestors, they also have to expect a relatively large variability in behavior and adjust their experimental design accordingly. In this chapter, we will lay out traditional and novel rodent models and paradigms to study sexual, affiliative, and aggressive interactions among adult conspecifics. We will discuss the merits and main findings and briefly consider the most promising novel directions. Finally, we review the modulatory involvement of two major players in mammal social interaction: the central oxytocin and vasopressin system.
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Affiliation(s)
- Michael Lukas
- Molecular and Behavioral Neurobiology, University of Regensburg, Regensburg, Germany.
| | - Trynke R de Jong
- Molecular and Behavioral Neurobiology, University of Regensburg, Regensburg, Germany
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83
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Acute and repeated intranasal oxytocin administration exerts anti-aggressive and pro-affiliative effects in male rats. Psychoneuroendocrinology 2015; 51:112-21. [PMID: 25305547 DOI: 10.1016/j.psyneuen.2014.09.019] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 09/18/2014] [Accepted: 09/18/2014] [Indexed: 11/24/2022]
Abstract
Socio-emotional deficits and impulsive/aggressive outbursts are prevalent symptoms of many neuropsychiatric disorders, and intranasal administration of oxytocin (OXT) is emerging as a putative novel therapeutic approach to curb these problems. Recently, we demonstrated potent anti-aggressive and pro-social effects of intracerebroventricular (icv) OXT administration in male rats. The present study tested whether similar behavioral effects are induced when OXT is delivered intranasally. Heart-rate and blood-pressure responses were telemetrically monitored to investigate whether peripheral physiological effects were provoked after intranasal OXT administration. Intranasal OXT administration in resident animals reduced offensive aggression and increased social exploration toward an unfamiliar male intruder. Using a partner-preference test, intranasal OXT also strengthened the bonding between the male resident and its female partner. No changes in cardiovascular (re)activity were found, indicating an absence of direct peripheral physiological effects after intranasal OXT treatment. In conclusion, although the precise route and mechanisms of nose-to-brain transport/communication remain to be elucidated, our data demonstrated intranasal OXT to be an effective application method for suppressing intermale aggression and enhancing social affiliation.
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84
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Hicks C, Ramos L, Reekie T, Misagh GH, Narlawar R, Kassiou M, McGregor IS. Body temperature and cardiac changes induced by peripherally administered oxytocin, vasopressin and the non-peptide oxytocin receptor agonist WAY 267,464: a biotelemetry study in rats. Br J Pharmacol 2014; 171:2868-87. [PMID: 24641248 DOI: 10.1111/bph.12613] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 01/14/2014] [Accepted: 01/26/2014] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE There is current interest in oxytocin (OT) as a possible therapeutic in psychiatric disorders. However, the usefulness of OT may be constrained by peripheral autonomic effects, which may involve an action at both OT and vasopressin V1A receptors. Here, we characterized the cardiovascular and thermoregulatory effects of OT, vasopressin (AVP) and the non-peptide OT receptor agonist WAY 267,464 in rats, and assessed the relative involvement of the OT and V1A receptors in these effects. EXPERIMENTAL APPROACH Biotelemetry in freely moving male Wistar rats was used to examine body temperature and heart rate after OT (0.01 - 1 mg kg(-1); i.p.), AVP (0.001 - 0.1 mg kg(-1); i.p.) or WAY 267,464 (10 and 100 mg kg(-1); i.p.). The actions of the OT receptor antagonist Compound 25 (C25, 5 and 10 mg kg(-1)) and V1A receptor antagonist SR49059 (1 and 10 mg kg(-1)) were studied, as well as possible V1A receptor antagonist effects of WAY 267,464. KEY RESULTS OT and AVP dose-dependently reduced body temperature and heart rate. WAY 267,464 had similar, but more modest, effects. SR49059, but not C25, prevented the hypothermia and bradycardia induced by OT and AVP. WAY 267,464 (100 mg·kg(-1)) prevented the effects of OT, and to some extent AVP. CONCLUSIONS AND IMPLICATIONS Peripherally administered OT and AVP have profound cardiovascular and thermoregulatory effects that appear to principally involve the V1A receptor rather than the OT receptor. Additionally, WAY 267,464 is not a simple OT receptor agonist, as it has functionally relevant V1A antagonist actions.
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Affiliation(s)
- C Hicks
- School of Psychology, University of Sydney, Sydney, NSW, Australia
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85
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Looking for prosocial genes: ITRAQ analysis of proteins involved in MDMA-induced sociability in mice. Eur Neuropsychopharmacol 2014; 24:1773-83. [PMID: 25241352 DOI: 10.1016/j.euroneuro.2014.08.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/25/2014] [Accepted: 08/10/2014] [Indexed: 12/20/2022]
Abstract
Social behavior plays a fundamental role in life of many animal species, allowing the interaction between individuals and sharing of experiences, needs, and goals across them. In humans, some neuropsychiatric diseases, including anxiety, posttraumatic stress disorder and autism spectrum disorders, are often characterized by impaired sociability. Here we report that N-Methyl-3,4-methylenedioxyamphetamine (MDMA, "Ecstasy") at low dose (3mg/kg) has differential effects on mouse social behavior. In some animals, MDMA promotes sociability without hyperlocomotion, whereas in other mice it elevates locomotor activity without affecting sociability. Both WAY-100635, a selective antagonist of 5-HT1A receptor, and L-368899, a selective oxytocin receptor antagonist, abolish prosocial effects of MDMA. Differential quantitative analysis of brain proteome by isobaric tag for relative and absolute quantification technology (iTRAQ) revealed 21 specific proteins that were highly correlated with sociability, and allowed to distinguish between entactogenic prosocial and hyperlocomotor effects of MDMA on proteome level. Our data suggest particular relevance of neurotransmission mediated by GABA B receptor, as well as proteins involved in energy maintenance for MDMA-induced sociability. Functional association network for differentially expressed proteins in cerebral cortex, hippocampus and amygdala were identified. These results provide new information for understanding the neurobiological substrate of sociability and may help to discover new therapeutic approaches to modulate social behavior in patients suffering from social fear and low sociability.
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86
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Oxytocin and vasopressin modulate the social response to threat: a preclinical study. Int J Neuropsychopharmacol 2014; 17:1621-33. [PMID: 24807123 DOI: 10.1017/s1461145714000388] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Individuals in many species increase their proximity to others in threatening situations (defensive aggregation), increasing their chance of survival and reducing the adverse psychological impact of stressors. However, the basic neurobiology of defensive aggregation is not well understood. Here we examined the role of the social neuropeptides oxytocin (OT) and vasopressin (AVP) in this response. Groups of rats were exposed to a ball of cat fur (an innate threat stimulus) in a large arena, causing prolonged periods of tight social grouping (huddling). The modulatory effects of OT and AVP on huddling were examined both alone and in conjunction with relevant antagonists. To determine specificity of treatment effects to social grouping, the effects of the same treatments were also assessed in individual rats exposed to cat fur and given the opportunity to hide. OT (0.5 mg/kg, i.p.) and AVP (0.01 mg/kg, i.p.) increased huddling in rats socially exposed to cat fur, whereas the selective V1A AVP receptor antagonist SR49059 (3 mg/kg, i.p.) decreased huddling. The effects of OT were prevented by pre-treatment with SR49059 (3 mg/kg), while those of AVP were prevented by the V1B receptor antagonist SSR149415 (30 mg/kg, i.p.). OT had no effect on huddling when groups of four rats were tested with no cat fur present whereas AVP increased huddling under these conditions. Neither OT, nor SR49059, affected hiding in individual rats exposed to cat fur. However, AVP increased hiding, an effect prevented by SSR149415 (30 mg/kg, i.p.). These results suggest that OT acts on V1A receptors to promote a social response to threat without altering the more general defensive response. Conversely, AVP appears to increase generalised anxiety via V1B receptors, which subsequently results in huddling. A hitherto unrecognised function of oxytocin is therefore to promote social affiliation during threatening situations.
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87
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A window into the intoxicated mind? Speech as an index of psychoactive drug effects. Neuropsychopharmacology 2014; 39:2340-8. [PMID: 24694926 PMCID: PMC4138742 DOI: 10.1038/npp.2014.80] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Revised: 01/20/2014] [Accepted: 03/24/2014] [Indexed: 11/09/2022]
Abstract
Abused drugs can profoundly alter mental states in ways that may motivate drug use. These effects are usually assessed with self-report, an approach that is vulnerable to biases. Analyzing speech during intoxication may present a more direct, objective measure, offering a unique 'window' into the mind. Here, we employed computational analyses of speech semantic and topological structure after ±3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') and methamphetamine in 13 ecstasy users. In 4 sessions, participants completed a 10-min speech task after MDMA (0.75 and 1.5 mg/kg), methamphetamine (20 mg), or placebo. Latent Semantic Analyses identified the semantic proximity between speech content and concepts relevant to drug effects. Graph-based analyses identified topological speech characteristics. Group-level drug effects on semantic distances and topology were assessed. Machine-learning analyses (with leave-one-out cross-validation) assessed whether speech characteristics could predict drug condition in the individual subject. Speech after MDMA (1.5 mg/kg) had greater semantic proximity than placebo to the concepts friend, support, intimacy, and rapport. Speech on MDMA (0.75 mg/kg) had greater proximity to empathy than placebo. Conversely, speech on methamphetamine was further from compassion than placebo. Classifiers discriminated between MDMA (1.5 mg/kg) and placebo with 88% accuracy, and MDMA (1.5 mg/kg) and methamphetamine with 84% accuracy. For the two MDMA doses, the classifier performed at chance. These data suggest that automated semantic speech analyses can capture subtle alterations in mental state, accurately discriminating between drugs. The findings also illustrate the potential for automated speech-based approaches to characterize clinically relevant alterations to mental state, including those occurring in psychiatric illness.
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88
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Schmid Y, Hysek CM, Simmler LD, Crockett MJ, Quednow BB, Liechti ME. Differential effects of MDMA and methylphenidate on social cognition. J Psychopharmacol 2014; 28:847-56. [PMID: 25052243 DOI: 10.1177/0269881114542454] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Social cognition is important in everyday-life social interactions. The social cognitive effects of 3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') and methylphenidate (both used for neuroenhancement and as party drugs) are largely unknown. We investigated the acute effects of MDMA (75 mg), methylphenidate (40 mg) and placebo using the Facial Emotion Recognition Task, Multifaceted Empathy Test, Movie for the Assessment of Social Cognition, Social Value Orientation Test and the Moral Judgment Task in a cross-over study in 30 healthy subjects. Additionally, subjective, autonomic, pharmacokinetic, endocrine and adverse drug effects were measured. MDMA enhanced emotional empathy for positive emotionally charged situations in the MET and tended to reduce the recognition of sad faces in the Facial Emotion Recognition Task. MDMA had no effects on cognitive empathy in the Multifaceted Empathy Test or social cognitive inferences in the Movie for the Assessment of Social Cognition. MDMA produced subjective 'empathogenic' effects, such as drug liking, closeness to others, openness and trust. In contrast, methylphenidate lacked such subjective effects and did not alter emotional processing, empathy or mental perspective-taking. MDMA but not methylphenidate increased the plasma levels of oxytocin and prolactin. None of the drugs influenced moral judgment. Effects on emotion recognition and emotional empathy were evident at a low dose of MDMA and likely contribute to the popularity of the drug.
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Affiliation(s)
- Yasmin Schmid
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
| | - Cédric M Hysek
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
| | - Linda D Simmler
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
| | - Molly J Crockett
- Wellcome Trust Centre for Neuroimaging, University College London, London, UK
| | - Boris B Quednow
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry Zurich, Zurich, Switzerland
| | - Matthias E Liechti
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
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89
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Kirkpatrick MG, Francis SM, Lee R, de Wit H, Jacob S. Plasma oxytocin concentrations following MDMA or intranasal oxytocin in humans. Psychoneuroendocrinology 2014; 46:23-31. [PMID: 24882155 PMCID: PMC4088952 DOI: 10.1016/j.psyneuen.2014.04.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 04/01/2014] [Accepted: 04/07/2014] [Indexed: 01/09/2023]
Abstract
MDMA (±3,4-methylenedioxymethamphetamine, 'ecstasy') is reportedly used recreationally because it increases feelings of sociability and interpersonal closeness. Prior work suggests that the pro-social effects of MDMA may be mediated by release of oxytocin. A direct examination of plasma levels of oxytocin after acute doses of oxytocin and MDMA, in the same individuals, would provide further evidence for the idea that MDMA produces its pro-social effects by increasing oxytocin. Fourteen healthy MDMA users participated in a 4-session, double-blind study in which they received oral MDMA (0.75 and 1.5mg/kg), intranasal oxytocin (20IU or 40IU), and placebo. Plasma oxytocin concentrations, as well as cardiovascular and subjective effects were assessed before and at several time points after drug administration. MDMA (1.5mg/kg only) increased plasma oxytocin levels to a mean peak of 83.7pg/ml at approximately 90-120min, compared to 18.6pg/ml after placebo. Intranasal oxytocin (40IU, but not 20IU) increased plasma oxytocin levels to 48.0pg/ml, 30-60min after nasal spray administration. MDMA dose-dependently increased heart rate, blood pressure, feelings of euphoria (e.g., 'High' and 'Like Drug'), and feelings of sociability, whereas oxytocin had no cardiovascular or subjective effects. The subjective and cardiovascular responses to MDMA were not related to plasma oxytocin levels, although the N was small for this analysis. Future studies examining the effects of oxytocin antagonists on responses to MDMA will help to determine the mechanism by which MDMA produces pro-social effects.
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Affiliation(s)
- Matthew G. Kirkpatrick
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA
| | - Sunday M. Francis
- Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA
| | - Royce Lee
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA.
| | - Suma Jacob
- Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA
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90
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Ramos L, Hicks C, Caminer A, McGregor IS. Inhaled vasopressin increases sociability and reduces body temperature and heart rate in rats. Psychoneuroendocrinology 2014; 46:46-51. [PMID: 24882157 DOI: 10.1016/j.psyneuen.2014.04.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 03/24/2014] [Accepted: 04/07/2014] [Indexed: 11/28/2022]
Abstract
The neuropeptides vasopressin (AVP) and oxytocin (OT) have therapeutic potential across a range of psychiatric disorders. However, there is uncertainty about the effectiveness of the intranasal route of administration that is often used to deliver these neuropeptides. Recent preclinical studies, typically involving anesthetized or restrained animals, have assessed intranasal AVP or OT effects, and have obtained somewhat inconsistent results. Here we obtained intranasal administration of AVP in rats by nebulizing the peptide (1ml of 5 or 10mg/ml solution) into a small enclosed chamber over a 2min period in which well-habituated, unanesthetized, unrestrained, rats were placed. Rats were immediately removed from the chamber and tested in the social interaction test, or assessed for changes in heart rate and body temperature using biotelemetry. Results showed that rats exposed to nebulized AVP (5 or 10mg/ml) showed increased social proximity (adjacent lying) and decreased anogenital sniffing in the social interaction test. Biotelemetry showed substantial and long lasting (>1h) hypothermic and bradycardic effects of nebulized AVP. These behavioral and physiological effects of nebulized AVP mimic those observed in recent studies with peripherally injected AVP. Plasma AVP concentrations were substantially increased 10min after nebulized AVP, producing levels above those seen with a behaviorally effective injected dose of AVP (0.005mg/kg intraperitoneal). This study thus provides a novel and effective method for neuropeptide administration to rodents.
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Affiliation(s)
- Linnet Ramos
- School of Psychology, Brennan MacCallum Building, University of Sydney, NSW 2006, Australia
| | - Callum Hicks
- School of Psychology, Brennan MacCallum Building, University of Sydney, NSW 2006, Australia
| | - Alex Caminer
- School of Psychology, Brennan MacCallum Building, University of Sydney, NSW 2006, Australia
| | - Iain S McGregor
- School of Psychology, Brennan MacCallum Building, University of Sydney, NSW 2006, Australia.
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91
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Oxytocin in the prelimbic medial prefrontal cortex reduces anxiety-like behavior in female and male rats. Psychoneuroendocrinology 2014; 45:31-42. [PMID: 24845174 PMCID: PMC4067951 DOI: 10.1016/j.psyneuen.2014.03.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 03/18/2014] [Accepted: 03/20/2014] [Indexed: 01/31/2023]
Abstract
The neuropeptide oxytocin (OT) is anxiolytic in rodents and humans. However, the specific brain regions where OT acts to regulate anxiety requires further investigation. The medial prefrontal cortex (mPFC) has been shown to play a role in the modulation of anxiety-related behavior. In addition, the mPFC contains OT-sensitive neurons, expresses OT receptors, and receives long range axonal projections from OT-producing neurons in the hypothalamus, suggesting that the mPFC may be a target where OT acts to diminish anxiety. To investigate this possibility, female rats were administered OT bilaterally into the prelimbic (PL) region of the mPFC and anxiety-like behavior assessed. In addition, to determine if the effects of OT on anxiety-like behavior are sex dependent and to evaluate the specificity of OT, male and female anxiety-like behavior was tested following delivery of either OT or the closely related neuropeptide arginine vasopressin (AVP) into the PL mPFC. Finally, the importance of endogenous OT in the regulation of anxiety-like behavior was examined in male and female rats that received PL infusions of an OT receptor antagonist (OTR-A). Overall, even though males and females showed some differences in their baseline levels of anxiety-like behavior, OT in the PL region of the mPFC decreased anxiety regardless of sex. In contrast, neither AVP nor an OTR-A affected anxiety-like behavior in males or females. Together, these findings suggest that although endogenous OT in the PL region of the mPFC does not influence anxiety, the PL mPFC is a site where exogenous OT may act to attenuate anxiety-related behavior independent of sex.
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92
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Kuypers KPC, de la Torre R, Farre M, Yubero-Lahoz S, Dziobek I, Van den Bos W, Ramaekers JG. No evidence that MDMA-induced enhancement of emotional empathy is related to peripheral oxytocin levels or 5-HT1a receptor activation. PLoS One 2014; 9:e100719. [PMID: 24972084 PMCID: PMC4074089 DOI: 10.1371/journal.pone.0100719] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/23/2014] [Indexed: 11/24/2022] Open
Abstract
The present study aimed at investigating the effect of MDMA on measures of empathy and social interaction, and the roles of oxytocin and the 5-HT1A receptor in these effects. The design was placebo-controlled within-subject with 4 treatment conditions: MDMA (75 mg), with or without pindolol (20 mg), oxytocin nasal spray (40 IU+16 IU) or placebo. Participants were 20 healthy poly-drug MDMA users, aged between 18–26 years. Cognitive and emotional empathy were assessed by means of the Reading the Mind in the Eyes Test and the Multifaceted Empathy Test. Social interaction, defined as trust and reciprocity, was assessed by means of a Trust Game and a Social Ball Tossing Game. Results showed that MDMA selectively affected emotional empathy and left cognitive empathy, trust and reciprocity unaffected. When combined with pindolol, these effects remained unchanged. Oxytocin did not affect measures of empathy and social interaction. Changes in emotional empathy were not related to oxytocin plasma levels. It was concluded that MDMA (75 mg) selectively enhances emotional empathy in humans. While the underlying neurobiological mechanism is still unknown, it is suggested that peripheral oxytocin does not seem to be the main actor in this; potential candidates are the serotonin 2A and the vasopressin 1A receptors. Trial Registration MDMA & PSB NTR 2636
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Affiliation(s)
- Kim P. C. Kuypers
- Dept. of Neuropsychology & Psychopharmacology, Fac. of Psychology & Neuroscience, Maastricht University, Maastricht, the Netherlands
- * E-mail:
| | - Rafael de la Torre
- IMIM- Hospital del Mar- Research institute, Human Pharmacology & Clinical Neurosciences Research Group, Barcelona, Spain
| | - Magi Farre
- IMIM- Hospital del Mar- Research institute, Human Pharmacology & Clinical Neurosciences Research Group, Barcelona, Spain
| | - Samanta Yubero-Lahoz
- IMIM- Hospital del Mar- Research institute, Human Pharmacology & Clinical Neurosciences Research Group, Barcelona, Spain
| | - Isabel Dziobek
- Cluster of Excellence Languages of Emotion, Freie Universität, Berlin, Germany
| | - Wouter Van den Bos
- Center for Adaptive Rationality (ARC), Max-Planck-Institute for Human Development, Berlin, Germany
| | - Johannes G. Ramaekers
- Dept. of Neuropsychology & Psychopharmacology, Fac. of Psychology & Neuroscience, Maastricht University, Maastricht, the Netherlands
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93
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Kirkpatrick MG, Lee R, Wardle MC, Jacob S, de Wit H. Effects of MDMA and Intranasal oxytocin on social and emotional processing. Neuropsychopharmacology 2014; 39:1654-63. [PMID: 24448644 PMCID: PMC4023138 DOI: 10.1038/npp.2014.12] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 01/11/2014] [Accepted: 01/15/2014] [Indexed: 11/09/2022]
Abstract
MDMA (± 3,4-methylenedioxymethamphetamine, 'ecstasy') is used recreationally, reportedly because it increases feelings of empathy, sociability, and interpersonal closeness. One line of evidence suggests that MDMA produces these effects by releasing oxytocin, a peptide involved in social bonding. In the current study, we investigated the acute effects of MDMA and oxytocin on social and emotional processing in healthy human volunteers. MDMA users (N = 65) participated in a 4-session, within-between-subjects study in which they received oral MDMA (0.75, 1.5 mg/kg), intranasal oxytocin (20 or 40 IU), or placebo under double-blind conditions. The primary outcomes included measures of emotion recognition and sociability (desire to be with others). Cardiovascular and subjective effects were also assessed. As expected, MDMA dose-dependently increased heart rate and blood pressure and feelings of euphoria (eg, 'High' and 'Like Drug'). On measures of social function, MDMA impaired recognition of angry and fearful facial expressions, and the larger dose (1.5 mg/kg) increased desire to be with others, compared with placebo. Oxytocin produced small but significant increases in feelings of sociability and enhanced recognition of sad facial expressions. Additionally, responses to oxytocin were related to responses to MDMA with subjects on two subjective measures of sociability. Thus, MDMA increased euphoria and feelings of sociability, perhaps by reducing sensitivity to subtle signs of negative emotions in others. The present findings provide only limited support for the idea that oxytocin produces the prosocial effects of MDMA.
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Affiliation(s)
- Matthew G Kirkpatrick
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA
| | - Royce Lee
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA
| | - Margaret C Wardle
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA
| | - Suma Jacob
- Department of Psychiatry, University of Minnesota, Chicago, IL, USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neurosciences, University of Chicago, Chicago, IL, USA,Department of Psychiatry and Behavioral Neuroscience, MC 3077, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA, Tel: +1 773 702 5855, Fax: +1 773 834 7698, E-mail:
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Suraev AS, Bowen MT, Ali SO, Hicks C, Ramos L, McGregor IS. Adolescent exposure to oxytocin, but not the selective oxytocin receptor agonist TGOT, increases social behavior and plasma oxytocin in adulthood. Horm Behav 2014; 65:488-96. [PMID: 24631584 DOI: 10.1016/j.yhbeh.2014.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 01/17/2014] [Accepted: 03/02/2014] [Indexed: 11/28/2022]
Abstract
There are indications that exposing adolescent rodents to oxytocin (OT) may have positive "trait-changing" effects resulting in increased sociability and decreased anxiety that last well beyond acute drug exposure and into adulthood. Such findings may have relevance to the utility of OT in producing sustained beneficial effects in human psychiatric conditions. The present study further examined these effects using an intermittent regime of OT exposure in adolescence, and using Long Evans rats, that are generally more sensitive to the acute prosocial effects of OT. As OT has substantial affinity for the vasopressin V1a receptor (V1aR) in addition to the oxytocin receptor (OTR), we examined whether a more selective peptidergic OTR agonist - [Thr4, Gly7]-oxytocin (TGOT) - would have similar lasting effects on behavior. Male Long Evans rats received OT or TGOT (0.5-1mg/kg, intraperitoneal), once every three days, for a total of 10 doses during adolescence (postnatal day (PND) 28-55). Social and anxiety-related behaviors were assessed during acute administration as well as later in adulthood (from PND 70 onwards). OT produced greater acute behavioral effects than TGOT, including an inhibition of social play and reduced rearing, most likely reflecting primary sedative effects. In adulthood, OT but not TGOT pretreated rats displayed lasting increases in social interaction, accompanied by an enduring increase in plasma OT. These findings confirm lasting behavioral and neuroendocrine effects of adolescent OT exposure. However, the absence of such effects with TGOT suggests possible involvement of the V1aR as well as the OTR in this example of developmental neuroplasticity.
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Affiliation(s)
| | - Michael T Bowen
- School of Psychology, University of Sydney, NSW 2006, Australia
| | - Sinan O Ali
- School of Psychology, University of Sydney, NSW 2006, Australia
| | - Callum Hicks
- School of Psychology, University of Sydney, NSW 2006, Australia
| | - Linnet Ramos
- School of Psychology, University of Sydney, NSW 2006, Australia
| | - Iain S McGregor
- School of Psychology, University of Sydney, NSW 2006, Australia.
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95
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Lukas M, Neumann ID. Social preference and maternal defeat-induced social avoidance in virgin female rats: sex differences in involvement of brain oxytocin and vasopressin. J Neurosci Methods 2014; 234:101-7. [PMID: 24709115 DOI: 10.1016/j.jneumeth.2014.03.013] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/24/2014] [Accepted: 03/25/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Research concerning non-reproductive sociability in rodents is mainly restricted to assessing the effects of oxytocin (OXT) and arginine-vasopressin (AVP) in male rats and mice. Comparable studies on natural social preference and social avoidance in females are substantially lacking. NEW METHOD Here, we adapted a behavioral paradigm for monitoring social preference of female rats consisting of two consecutive exposures to either non-social or social stimuli. Further, to induce stimulus-specific social avoidance, female rats were exposed to a single 10-min maternal defeat by a lactating dam. RESULTS Social preference towards same-sex conspecifics in female rats was shown to be independent of the estrous cycle and even more pronounced than in male rats. Intracerebroventricular (icv) application of OXT, AVP, or their selective receptor antagonists or agonists, did not alter naturally-occurring social preference in female rats. Stimulus-specific social avoidance could be induced by prior exposure to a lactating rat: an effect that could not be reversed/overcome by icv OXT. COMPARISON WITH EXISTING METHOD(S) The female social preference paradigm for rats established in this study detected subtle sex differences in social preference behavior of rats. Further, stimulus-specific social deficits could be induced in female rats using an acute exposure to social defeat - as previously observed in male rodents. CONCLUSIONS Female rats show strong social preference behavior, which can be prevented by social defeat, but does not seem to be regulated by the OXT or AVP systems. Accordingly, icv application of synthetic OXT does not reverse maternal defeat-induced social avoidance in female rats.
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Affiliation(s)
- Michael Lukas
- Department of Behavioral and Molecular Neurobiology, University of Regensburg, 93053 Regensburg, Germany.
| | - Inga D Neumann
- Department of Behavioral and Molecular Neurobiology, University of Regensburg, 93053 Regensburg, Germany
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96
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Wardle MC, Kirkpatrick MG, de Wit H. 'Ecstasy' as a social drug: MDMA preferentially affects responses to emotional stimuli with social content. Soc Cogn Affect Neurosci 2014; 9:1076-81. [PMID: 24682132 DOI: 10.1093/scan/nsu035] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is used recreationally to improve mood and sociability, and has generated clinical interest as a possible adjunct to psychotherapy. One way that MDMA may produce positive 'prosocial' effects is by changing responses to emotional stimuli, especially stimuli with social content. Here, we examined for the first time how MDMA affects subjective responses to positive, negative and neutral emotional pictures with and without social content. We hypothesized that MDMA would dose-dependently increase reactivity to positive emotional stimuli and dampen reactivity to negative stimuli, and that these effects would be most pronounced for pictures with people in them. The data were obtained from two studies using similar designs with healthy occasional MDMA users (total N = 101). During each session, participants received MDMA (0, 0.75 and 1.5 mg/kg oral), and then rated their positive and negative responses to standardized positive, negative and neutral pictures with and without social content. MDMA increased positive ratings of positive social pictures, but reduced positive ratings of non-social positive pictures. We speculate this 'socially selective' effect contributes to the prosocial effects of MDMA by increasing the comparative value of social contact and closeness with others. This effect may also contribute to its attractiveness to recreational users.
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Affiliation(s)
- Margaret C Wardle
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL 60637, USA
| | - Matthew G Kirkpatrick
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL 60637, USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL 60637, USA
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