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Jing L, Ma C, Xu L, Richter-Levin G. Distinct Neural Representations and Cognitive Behaviors Attributable to Naturally Developed Active Avoidance or Reactive Escape Strategies in the Male Rat. Int J Neuropsychopharmacol 2023; 26:761-772. [PMID: 37725443 PMCID: PMC10674082 DOI: 10.1093/ijnp/pyad054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 09/18/2023] [Indexed: 09/21/2023] Open
Abstract
BACKGROUND The high individual variability in coping with stress is often attributed to genetic background differences, sustained environmental conditions, or a combination of both. However, the neural mechanisms underlying coping style variability are still poorly understood. METHODS Here we examined the impact of a single extended emotional challenge on coping style variability and the associated involvement of the hippocampus, medial prefrontal cortex (mPFC), and periaqueductal gray (PAG). Male Sprague-Dawley rats (n = 170) were trained in an extended 2-way shuttle avoidance (eTWSA) task for 7 days, and daily avoidance rates were measured. Forced swim test, elevated plus maze, or Morris water maze was tested before or after eTWSA exposure. Excitotoxic lesion of the hippocampal dentate gyrus (DG) was performed by Ibotenic infusion. Transient pharmacological blocking of DG, mPFC, or PAG was performed by muscimol or CNQX+TTX infusion. RESULTS Exposing rats to eTWSA was found to lead to naturally developing dichotomous, not continuous, coping styles, which we termed active avoidance (AA) or reactive escape (RE). Prior emotional responses did not predict the developing coping style. AA was associated with beneficial outcomes, including reduced behavioral despair and improved spatial learning. RE led to impaired spatial retrieval. AA was abolished by lesioning or pharmacological blocking of the DG. RE was prevented by blocking mPFC or PAG. CONCLUSION The results indicate that a single exposure to a significant emotional challenge can lead, in otherwise healthy individuals, to dichotomous development of an active or reactive coping style with distinctive neural correlates and subsequent behavioral significance.
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Affiliation(s)
- Liang Jing
- Sagol Department of Neurobiology, Department of Psychology, University of Haifa, Haifa, Israel
- The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Israel
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China
| | - Chen Ma
- Sagol Department of Neurobiology, Department of Psychology, University of Haifa, Haifa, Israel
- Key Laboratory of Animal Models and Human Disease Mechanisms, Lab of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Israel
| | - Lin Xu
- Key Laboratory of Animal Models and Human Disease Mechanisms, Lab of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- CAS Centre for Excellence in Brain Science and Intelligent Technology, Shanghai, China
- Mental Health Institute, Second Xiangya Hospital of Central South University, Changsha, China
- KIZ-SU Joint Laboratory of Animal Model and Drug Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Gal Richter-Levin
- Sagol Department of Neurobiology, Department of Psychology, University of Haifa, Haifa, Israel
- The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, Israel
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Zhang J, Li W, Liao T, Li M, Yao X, Zhang Y, Zhang B, Zhang J, Jiang X, Wang K, Jing L. Diazepam promotes active avoidance extinction associating with increased dorsal CA3 and amygdala activity. Brain Res 2023; 1817:148481. [PMID: 37429455 DOI: 10.1016/j.brainres.2023.148481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/05/2023] [Accepted: 07/07/2023] [Indexed: 07/12/2023]
Abstract
Active avoidance (AA) is an adaptive response to potentially harmful situations while maladapted avoidance that does not extinguish is one of the core symptoms of anxiety and post-traumatic stress disorder. However, the neural mechanisms of AA extinction and its relationship to anxiety remain unclear. We examined AA extinction during three extinction training sessions in two-way active avoidance paradigm and tested the effect of anxiolytic on AA extinction. Then we performed a meta-analysis of rodent studies, identified anxiolytic diazepam facilitates AA acquisition, and tested the same treatment in AA extinction. Diazepam-treated rats significantly reduced avoidance in the first two extinction training, compared with the saline-treated rats, and the reduction in avoidance remained in the third drug-free session. Then we explored extinction associated hippocampal and amygdala activity in saline-and diazepam-treated rats using c-Fos immunostaining following the last extinction session. The density of c-Fos positive cells was higher in dorsal CA3 of the diazepam group than in that of saline-treated animals, and was also higher in the central and basolateral amygdala regions of diazepam-treated rats than in that of saline-treated animals. Combined, these results suggest anxiolytics promotes AA extinction associated with dorsal CA3 and amygdala activity changes.
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Affiliation(s)
- Juan Zhang
- Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wenjun Li
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China
| | - Taohong Liao
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China
| | - Meijuan Li
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China
| | - Xiaoqing Yao
- Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yan Zhang
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China
| | - Bingyu Zhang
- Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Juanjuan Zhang
- Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xiao Jiang
- Research Center for Translational Medicine, The Second Hospital of Anhui Medical University, Hefei, China; The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China..
| | - Kai Wang
- The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China.; Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
| | - Liang Jing
- Research Center for Translational Medicine, The Second Hospital of Anhui Medical University, Hefei, China; The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China..
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3
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Mathieson E, Irving C, Koberna S, Nicholson M, Otto MW, Kantak KM. Role of preexisting inhibitory control deficits vs. drug use history in mediating insensitivity to aversive consequences in a rat model of polysubstance use. Psychopharmacology (Berl) 2022; 239:2377-2394. [PMID: 35391547 PMCID: PMC8989405 DOI: 10.1007/s00213-022-06134-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 03/30/2022] [Indexed: 10/26/2022]
Abstract
RATIONALE The nature and predictors of insensitivity to aversive consequences of heroin + cocaine polysubstance use are not well characterized. OBJECTIVES Translational methods incorporating a tightly controlled animal model of drug self-administration and measures of inhibitory control and avoidance behavior might be helpful for clarifying this issue. METHODS The key approach for distinguishing potential contributions of pre-existing inhibitory control deficits vs. drug use history in meditating insensitivity to aversive consequences was comparison of two rat strains: Wistar (WIS/Crl), an outbred strain, and the spontaneously hypertensive rat (SHR/NCrl), an inbred strain shown previously to exhibit heightened cocaine and heroin self-administration and poor inhibitory control relative to WIS/Crl. RESULTS In separate tasks, SHR/NCrl displayed greater impulsive action and compulsive-like behavior than WIS/Crl prior to drug exposure. Under two different schedules of drug delivery, SHR/NCrl self-administered more cocaine than WIS/Crl, but self-administered a similar amount of heroin + cocaine as WIS/Crl. When half the session cycles were punished by random foot shock, SHR/NCrl initially were less sensitive to punishment than WIS/Crl when self-administering cocaine, but were similarly insensitive to punishment when self-administering heroin + cocaine. Based on correlation analyses, only trait impulsivity predicted avoidance capacity in rats self-administering cocaine and receiving yoked-saline. In contrast, only amount of drug use predicted avoidance capacity in rats self-administering heroin + cocaine. Additionally, baseline drug seeking and taking predicted punishment insensitivity in rats self-administering cocaine or heroin + cocaine. CONCLUSIONS Based on the findings revealed in this animal model, human laboratory research concerning the nature and predictors of insensitivity to aversive consequences in heroin and cocaine polysubstance vs. monosubstance users is warranted.
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Affiliation(s)
- Elon Mathieson
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA
| | - Carolyn Irving
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA
| | - Sarah Koberna
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA
| | - Megan Nicholson
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA
| | - Michael W Otto
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA
| | - Kathleen M Kantak
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA.
- Center for Systems Neuroscience, Boston University, Boston, MA, USA.
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Fernández-Teruel A, Tobeña A. Revisiting the role of anxiety in the initial acquisition of two-way active avoidance: pharmacological, behavioural and neuroanatomical convergence. Neurosci Biobehav Rev 2020; 118:739-758. [PMID: 32916193 DOI: 10.1016/j.neubiorev.2020.08.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 07/10/2020] [Accepted: 08/15/2020] [Indexed: 12/19/2022]
Abstract
Two-way active avoidance (TWAA) acquisition constitutes a particular case of approach -avoidance conflict for laboratory rodents. The present article reviews behavioural, psychopharmacological and neuroanatomical evidence accumulated along more than fifty years that provides strong support to the contention that anxiety is critical in the transition from CS (conditioned stimulus)-induced freezing to escape/avoidance responses during the initial stages of TWAA acquisition. Thus, anxiolytic drugs of different types accelerate avoidance acquisition, anxiogenic drugs impair it, and avoidance during these initial acquisition stages is negatively associated with other typical measures of anxiety. In addition behavioural and developmental treatments that reduce or increase anxiety/stress respectively facilitate or impair TWAA acquisition. Finally, evidence for the regulation of TWAA acquisition by septo-hippocampal and amygdala-related mechanisms is discussed. Collectively, the reviewed evidence gives support to the initial acquisition of TWAA as a paradigm with considerable predictive and (in particular) construct validity as an approach-avoidance conflict-based rodent anxiety model.
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Affiliation(s)
- Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Autonomous University of Barcelona, 08193-Bellaterra, Barcelona, Spain.
| | - Adolf Tobeña
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, School of Medicine, Autonomous University of Barcelona, 08193-Bellaterra, Barcelona, Spain
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5
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A missing link between depression models: Forced swimming test, helplessness and passive coping in genetically heterogeneous NIH-HS rats. Behav Processes 2020; 177:104142. [DOI: 10.1016/j.beproc.2020.104142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/28/2020] [Accepted: 05/17/2020] [Indexed: 01/11/2023]
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6
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Giorgi O, Corda MG, Fernández-Teruel A. A Genetic Model of Impulsivity, Vulnerability to Drug Abuse and Schizophrenia-Relevant Symptoms With Translational Potential: The Roman High- vs. Low-Avoidance Rats. Front Behav Neurosci 2019; 13:145. [PMID: 31333426 PMCID: PMC6624787 DOI: 10.3389/fnbeh.2019.00145] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/18/2019] [Indexed: 12/14/2022] Open
Abstract
The bidirectional selective breeding of Roman high- (RHA) and low-avoidance (RLA) rats for respectively rapid vs. poor acquisition of active avoidant behavior has generated two lines/strains that differ markedly in terms of emotional reactivity, with RHA rats being less fearful than their RLA counterparts. Many other behavioral traits have been segregated along the selection procedure; thus, compared with their RLA counterparts, RHA rats behave as proactive copers in the face of aversive conditions, display a robust sensation/novelty seeking (SNS) profile, and show high impulsivity and an innate preference for natural and drug rewards. Impulsivity is a multifaceted behavioral trait and is generally defined as a tendency to express actions that are poorly conceived, premature, highly risky or inappropriate to the situation, that frequently lead to unpleasant consequences. High levels of impulsivity are associated with several neuropsychiatric conditions including attention-deficit hyperactivity disorder, obsessive-compulsive disorder, schizophrenia, and drug addiction. Herein, we review the behavioral and neurochemical differences between RHA and RLA rats and survey evidence that RHA rats represent a valid genetic model, with face, construct, and predictive validity, to investigate the neural underpinnings of behavioral disinhibition, novelty seeking, impulsivity, vulnerability to drug addiction as well as deficits in attentional processes, cognitive impairments and other schizophrenia-relevant traits.
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Affiliation(s)
- Osvaldo Giorgi
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Maria G Corda
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Universitat Autónoma de Barcelona, Barcelona, Spain
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7
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Río-Álamos C, Piludu MA, Gerbolés C, Barroso D, Oliveras I, Sánchez-González A, Cañete T, Tapias-Espinosa C, Sampedro-Viana D, Torrubia R, Tobeña A, Fernández-Teruel A. Volumetric brain differences between the Roman rat strains: Neonatal handling effects, sensorimotor gating and working memory. Behav Brain Res 2019; 361:74-85. [DOI: 10.1016/j.bbr.2018.12.033] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 11/23/2018] [Accepted: 12/17/2018] [Indexed: 12/20/2022]
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8
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Coping-Style Behavior Identified by a Survey of Parent-of-Origin Effects in the Rat. G3-GENES GENOMES GENETICS 2018; 8:3283-3291. [PMID: 30135107 PMCID: PMC6169385 DOI: 10.1534/g3.118.200489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this study we investigate the effects of parent of origin on complex traits in the laboratory rat, with a focus on coping style behavior in stressful situations. We develop theory, based on earlier work, to partition heritability into a component due to a combination of parent of origin, maternal, paternal and shared environment, and another component that estimates classical additive genetic variance. We use this theory to investigate the effects on heritability of the parental origin of alleles in 798 outbred heterogeneous stock rats across 199 complex traits. Parent-of-origin-like heritability was on average 2.7fold larger than classical additive heritability. Among the phenotypes with the most enhanced parent-of-origin heritability were 10 coping style behaviors, with average 3.2 fold heritability enrichment. To confirm these findings on coping behavior, and to eliminate the possibility that the parent of origin effects are due to confounding with shared environment, we performed a reciprocal F1 cross between the behaviorally divergent RHA and RLA rat strains. We observed parent-of-origin effects on F1 rat anxiety/coping-related behavior in the Elevated Zero Maze test. Our study is the first to assess genetic parent-of-origin effects in rats, and confirm earlier findings in mice that such effects influence coping and impulsive behavior, and suggest these effects might be significant in other mammals, including humans.
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9
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Affiliation(s)
- A Fernández-Teruel
- Department of Psychiatry and Forensic Medicine (Medical Psychology Unit), Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - A Tobeña
- Department of Psychiatry and Forensic Medicine (Medical Psychology Unit), Institute of Neurosciences, School of Medicine, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
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10
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Padurariu M, Antioch I, Balmus I, Ciobica A, El-Lethey HS, Kamel MM. Describing some behavioural animal models of anxiety and their mechanistics with special reference to oxidative stress and oxytocin relevance. Int J Vet Sci Med 2017; 5:98-104. [PMID: 30255057 PMCID: PMC6137856 DOI: 10.1016/j.ijvsm.2017.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/14/2017] [Accepted: 08/29/2017] [Indexed: 12/14/2022] Open
Abstract
It is now generally accepted that animal studies are playing an important role in the understanding of anxiety disorders, since they contribute to the current knowledge regarding the mechanisms and possible therapeutic approaches in anxiety. In the present review we will detail some essential aspects of behavioral animal models of anxiety related to social defeat paradigm, elevated plus maze, elevated zero or T maze, light/dark box, social interaction test or tests based on predator models, considering the latest theories and methodological approaches in this area of research, as well as our previous studies focusing on anxiety manifestations in a variety of species including rats, zebrafish, dogs and pigs. Moreover, in this context, we will focus on the recent theories concerning oxidative stress, as well as importance of oxytocin administration (especially the intranasal route). This could be important considering that these two factors are currently being investigated as possible mechanisms (oxidative stress status) and related therapeutic target (both intranasal oxytocin and antioxidants) in the pathology of the anxiety disorders.
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Affiliation(s)
- Manuela Padurariu
- “Grigore T. Popa” University of Medicine and Pharmacy, 16, Universitatii Street, 700115 Iasi, Romania
| | - Iulia Antioch
- “Alexandru Ioan Cuza” University, 11, Carol I, 700506 Iaşi, Romania
| | - Ioana Balmus
- “Alexandru Ioan Cuza” University, 11, Carol I, 700506 Iaşi, Romania
| | - Alin Ciobica
- Department of Research, Faculty of Biology, “Alexandru Ioan Cuza” University, 11, Carol I, 700506 Iaşi, Romania
- Center of Biomedical Research of the Romanian Academy, Iasi Branch, Romania
- The Academy of the Romanian Scientists, Bucharest, Splaiul Independentei 54, 050094, Romania
| | - Heba S. El-Lethey
- Department of Animal Hygiene and Management, Faculty of Veterinary Medicine, Cairo University, Cairo, Egypt
| | - Mervat M. Kamel
- Department of Animal Hygiene and Management, Faculty of Veterinary Medicine, Cairo University, Cairo, Egypt
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11
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Acoustic startle response in rats predicts inter-individual variation in fear extinction. Neurobiol Learn Mem 2017; 139:157-164. [PMID: 28131759 DOI: 10.1016/j.nlm.2017.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/12/2017] [Accepted: 01/19/2017] [Indexed: 11/23/2022]
Abstract
Although a large portion of the population is exposed to a traumatic event at some point, only a small percentage of the population develops post-traumatic stress disorder (PTSD), suggesting the presence of predisposing factors. Abnormal acoustic startle response (ASR) has been shown to be associated with PTSD, implicating it as a potential predictor of the development of PTSD-like behavior. Since poor extinction and retention of extinction learning are characteristic of PTSD patients, it is of interest to determine if abnormal ASR is predictive of development of such deficits. To determine whether baseline ASR has utility in predicting the development of PTSD-like behavior, the relationship between baseline ASR and freezing behavior following Pavlovian fear conditioning was examined in a group of adult, male Sprague-Dawley rats. Baseline acoustic startle response (ASR) was assessed preceding exposure to a Pavlovian fear conditioning paradigm where freezing behavior was measured during fear conditioning, extinction training, and extinction testing. Although there was no relationship between baseline ASR and fear memory following conditioning, rats with low baseline ASR had significantly lower magnitude of retention of the extinction memory than rats with high baseline ASR. The results suggest that baseline ASR has value as a predictive index of the development of a PTSD-like phenotype.
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12
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Ayers L, Agostini A, Schulkin J, Rosen JB. Effects of oxytocin on background anxiety in rats with high or low baseline startle. Psychopharmacology (Berl) 2016; 233:2165-2172. [PMID: 27004789 PMCID: PMC4864502 DOI: 10.1007/s00213-016-4267-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 02/29/2016] [Indexed: 01/17/2023]
Abstract
RATIONALE Oxytocin has antianxiety properties in humans and rodents. However, the antianxiety effects have been variable. OBJECTIVES To reduce variability and to strengthen the antianxiety effect of oxytocin in fear-potentiated startle, two experiments were performed. First, different amounts of light-shock pairings were given to determine the optimal levels of cue-specific fear conditioning and non-predictable startle (background anxiety). Second, the antianxiety effects of oxytocin were examined in rats with high and low pre-fear conditioning baseline startle to determine if oxytocin differentially affects high and low trait anxiety rats. METHODS Baseline pre-fear conditioning startle responses were first measured. Rats then received 1, 5, or 10 light-shock pairings. Fear-potentiated startle was then tested with two trial types: light-cued startle and non-cued startle trials. In the second experiment, rats fear conditioned with 10 light-shock pairings were administered either saline or oxytocin before a fear-potentiated startle test. Rats were categorized as low or high startlers by their pre-fear conditioning startle amplitude. RESULTS Ten shock pairings produced the largest non-cued startle responses (background anxiety), without increasing cue-specific fear-potentiated startle compared to one and five light-shock pairings. Cue-specific fear-potentiated startle was unaffected by oxytocin. Oxytocin reduced background anxiety only in rats with low pre-fear startle responses. CONCLUSIONS Oxytocin has population selective antianxiety effects on non-cued unpredictable threat, but only in rats with low pre-fear baseline startle responses. The low startle responses are reminiscent of humans with low startle responses and high trait anxiety.
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Affiliation(s)
- Luke Ayers
- Department of Psychology, Widener University, Chester, PA
| | - Andrew Agostini
- Department of Psychological and Brain Sciences, University of
Delaware, Newark, DE
| | - Jay Schulkin
- Department of Neuroscience, Georgetown University, Washington,
DC
| | - Jeffrey B. Rosen
- Department of Psychological and Brain Sciences, University of
Delaware, Newark, DE
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13
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Variability in emotional responsiveness and coping style during active avoidance as a window onto psychological vulnerability to stress. Physiol Behav 2016; 158:90-9. [PMID: 26922874 DOI: 10.1016/j.physbeh.2016.02.036] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/23/2016] [Accepted: 02/24/2016] [Indexed: 10/22/2022]
Abstract
Individual differences in coping styles are associated with psychological vulnerability to stress. Recent animal research suggests that coping styles reflect trade-offs between proactive and reactive threat responses during active avoidance paradigms, with proactive responses associated with better stress tolerance. Based on these preclinical findings, we developed a novel instructed active avoidance paradigm to characterize patterns of proactive and reactive responses using behavioral, motoric, and autonomic measures in humans. Analyses revealed significant inter-individual variability not only in the magnitude of general emotional responsiveness but also the likelihood to specifically express proactive or reactive responses. In men but not women, individual differences in general emotional responsiveness were linked to increased trait anxiety while proactive coping style was linked to increased trait aggression. These patterns are consistent with preclinical findings and suggest that instructed active avoidance paradigms may be useful in assessing psychological vulnerability to stress using objective behavioral measures.
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14
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Sánchez-González A, Esnal A, Río-Álamos C, Oliveras I, Cañete T, Blázquez G, Tobeña A, Fernández-Teruel A. Association between prepulse inhibition of the startle response and latent inhibition of two-way avoidance acquisition: A study with heterogeneous NIH-HS rats. Physiol Behav 2015; 155:195-201. [PMID: 26700617 DOI: 10.1016/j.physbeh.2015.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 12/20/2022]
Abstract
This study presents the first evaluation of the associations between responses in two paradigms related to schizophrenia in the genetically heterogeneous NIH-HS rat stock. NIH-HS rats are a stock of genetically heterogeneous animals that have been derived from eight different inbred strains. A rotational breeding schedule has been followed for more than eighty generations, leading to a high level of genetic recombination that makes the NIH-HS rats a unique tool for studying the genetic basis of (biological, behavioral, disease-related) complex traits. Previous work has dealt with the characterization of coping styles, cognitive and anxiety/fear-related profiles of NIH-HS rats. In the present study we have completed their characterization in two behavioral models, prepulse inhibition (PPI) and latent inhibition (LI) of the two-way active avoidance response, that appear to be related to schizophrenia or to schizophrenia-relevant symptoms. We have found that these rats display PPI for each of the four prepulse intensities tested, allowing their stratification in high, medium and low PPI subgroups. When testing these three subgroups for LI of two-way active avoidance acquisition it has been observed that the LowPPI and MediumPPI subgroups present impaired LI, which, along with the fact that the HighPPI group presents significant LI, allows us to hypothesize that responses in these two paradigms are somehow related and that selection of NIH-HS rats for Low vs HighPPI could make a promising animal model for the study of clusters of schizophrenia-relevant symptoms and their underlying neurobiological mechanisms.
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Affiliation(s)
- Ana Sánchez-González
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain.
| | - Aitor Esnal
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Cristóbal Río-Álamos
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Ignasi Oliveras
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Toni Cañete
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Gloria Blázquez
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Adolf Tobeña
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain.
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15
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Lalanza JF, Sanchez-Roige S, Cigarroa I, Gagliano H, Fuentes S, Armario A, Capdevila L, Escorihuela RM. Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats. Sci Rep 2015; 5:16166. [PMID: 26538081 PMCID: PMC4633642 DOI: 10.1038/srep16166] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 10/05/2015] [Indexed: 12/11/2022] Open
Abstract
Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.
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Affiliation(s)
- Jaume F Lalanza
- Institut de Neurociències, Departament de Psiquiatria i Medicina Legal, Fac de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain.,Laboratori de Psicologia de l'Esport, Departament de Psicologia Bàsica, Fac Psicologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Sandra Sanchez-Roige
- Institut de Neurociències, Departament de Psiquiatria i Medicina Legal, Fac de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Igor Cigarroa
- Institut de Neurociències, Departament de Psiquiatria i Medicina Legal, Fac de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain.,Carrera de Kinesiología, Facultad de Salud, Universidad Santo Tomás, Los Ángeles, región del Bio-Bio, Chile
| | - Humberto Gagliano
- Red de trastornos adictivos (RTA) and Institut de Neurociències, Unitat de Fisiologia Animal, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Silvia Fuentes
- Red de trastornos adictivos (RTA) and Institut de Neurociències, Unitat de Fisiologia Animal, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Antonio Armario
- Red de trastornos adictivos (RTA) and Institut de Neurociències, Unitat de Fisiologia Animal, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Lluís Capdevila
- Laboratori de Psicologia de l'Esport, Departament de Psicologia Bàsica, Fac Psicologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Rosa M Escorihuela
- Institut de Neurociències, Departament de Psiquiatria i Medicina Legal, Fac de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
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Río-Ȧlamos C, Oliveras I, Cañete T, Blázquez G, Martínez-Membrives E, Tobeña A, Fernández-Teruel A. Neonatal handling decreases unconditioned anxiety, conditioned fear, and improves two-way avoidance acquisition: a study with the inbred Roman high (RHA-I)- and low-avoidance (RLA-I) rats of both sexes. Front Behav Neurosci 2015. [PMID: 26217201 PMCID: PMC4498386 DOI: 10.3389/fnbeh.2015.00174] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The present study evaluated the long-lasting effects of neonatal handling (NH; administered during the first 21 days of life) on unlearned and learned anxiety-related responses in inbred Roman High- (RHA-I) and Low-avoidance (RLA-I) rats. To this aim, untreated and neonatally-handled RHA-I and RLA-I rats of both sexes were tested in the following tests/tasks: a novel object exploration (NOE) test, the elevated zero maze (ZM) test, a “baseline acoustic startle” (BAS) test, a “context-conditioned fear” (CCF) test and the acquisition of two-way active—shuttle box—avoidance (SHAV). RLA-I rats showed higher unconditioned (novel object exploration test -“NOE”-, elevated zero maze test -“ZM”-, BAS), and conditioned (CCF, SHAV) anxiety. NH increased exploration of the novel object in the NOE test as well as exploration of the open sections of the ZM test in both rat strains and sexes, although the effects were relatively more marked in the (high anxious) RLA-I strain and in females. NH did not affect BAS, but reduced CCF in both strains and sexes, and improved shuttle box avoidance acquisition especially in RLA-I (and particularly in females) and in female RHA-I rats. These are completely novel findings, which indicate that even some genetically-based anxiety/fear-related phenotypes can be significantly modulated by previous environmental experiences such as the NH manipulation.
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Affiliation(s)
- Cristóbal Río-Ȧlamos
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Ignasi Oliveras
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Toni Cañete
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Gloria Blázquez
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Esther Martínez-Membrives
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Adolf Tobeña
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of Barcelona Barcelona, Spain
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Martínez-Membrives E, López-Aumatell R, Blázquez G, Cañete T, Tobeña A, Fernández-Teruel A. Spatial learning in the genetically heterogeneous NIH-HS rat stock and RLA-I/RHA-I rats: revisiting the relationship with unconditioned and conditioned anxiety. Physiol Behav 2015; 144:15-25. [PMID: 25747770 DOI: 10.1016/j.physbeh.2015.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/27/2015] [Accepted: 03/02/2015] [Indexed: 12/15/2022]
Abstract
To characterize learning/memory profiles for the first time in the genetically heterogeneous NIH-HS rat stock, and to examine whether these are associated with anxiety, we evaluated NIH-HS rats for spatial learning/memory in the Morris water maze (MWM) and in the following anxiety/fear tests: the elevated zero-maze (ZM; unconditioned anxiety), a context-conditioned fear test and the acquisition of two-way active avoidance (conditioned anxiety). NIH-HS rats were compared with the Roman High- (RHA-I) and Low-Avoidance (RLA-I) rat strains, given the well-known differences between the Roman strains/lines in anxiety-related behavior and in spatial learning/memory. The results show that: (i) As expected, RLA-I rats were more anxious in the ZM test, displayed more frequent context-conditioned freezing episodes and fewer avoidances than RHA-I rats. (ii) Scores of NIH-HS rats in these tests/tasks mostly fell in between those of the Roman rat strains, and were usually closer to the values of the RLA-I strain. (iii) Pigmented NIH-HS (only a small part of NIH-HS rats were albino) rats were the best spatial learners and displayed better spatial memory than the other three (RHA-I, RLA-I and NIH-HS albino) groups. (iv) Albino NIH-HS and RLA-I rats also showed better learning/memory than the RHA-I strain. (v) Within the NIH-HS stock, the most anxious rats in the ZM test presented the best learning and/or memory efficiency (regardless of pigmentation). In summary, NIH-HS rats display a high performance in spatial learning/memory tasks and a passive coping strategy when facing conditioned conflict situations. In addition, unconditioned anxiety in NIH-HS rats predicts better spatial learning/memory.
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Affiliation(s)
- Esther Martínez-Membrives
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
| | - Regina López-Aumatell
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Gloria Blázquez
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Toni Cañete
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Adolf Tobeña
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
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Oliveras I, Río-Álamos C, Cañete T, Blázquez G, Martínez-Membrives E, Giorgi O, Corda MG, Tobeña A, Fernández-Teruel A. Prepulse inhibition predicts spatial working memory performance in the inbred Roman high- and low-avoidance rats and in genetically heterogeneous NIH-HS rats: relevance for studying pre-attentive and cognitive anomalies in schizophrenia. Front Behav Neurosci 2015; 9:213. [PMID: 26347624 PMCID: PMC4539526 DOI: 10.3389/fnbeh.2015.00213] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 07/30/2015] [Indexed: 01/10/2023] Open
Abstract
Animal models of schizophrenia-relevant symptoms are increasingly important for progress in our understanding of the neurobiological basis of the disorder and for discovering novel and more specific treatments. Prepulse inhibition (PPI) and working memory, which are impaired in schizophrenic patients, are among the symptoms/processes modeled in those animal analogs. We have evaluated whether a genetically-selected rat model, the Roman high-avoidance inbred strain (RHA-I), displays PPI deficits as compared with its Roman low-avoidance (RLA-I) counterpart and the genetically heterogeneous NIH-HS rat stock. We have investigated whether PPI deficits predict spatial working memory impairments (in the Morris water maze; MWM) in these three rat types (Experiment 1), as well as in a separate sample of NIH-HS rats stratified according to their extreme (High, Medium, Low) PPI scores (Experiment 2). The results from Experiment 1 show that RHA-I rats display PPI and spatial working memory deficits compared to both RLA-I and NIH-HS rats. Likewise, in Experiment 2, "Low-PPI" NIH-HS rats present significantly impaired working memory with respect to "Medium-PPI" and "High-PPI" NIH-HS subgroups. Further support to these results comes from correlational, factorial, and multiple regression analyses, which reveal that PPI is positively associated with spatial working memory performance. Conversely, cued learning in the MWM was not associated with PPI. Thus, using genetically-selected and genetically heterogeneous rats, the present study shows, for the first time, that PPI is a positive predictor of performance in a spatial working memory task. These results may have translational value for schizophrenia symptom research in humans, as they suggest that either by psychogenetic selection or by focusing on extreme PPI scores from a genetically heterogeneous rat stock, it is possible to detect a useful (perhaps "at risk") phenotype to study cognitive anomalies linked to schizophrenia.
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Affiliation(s)
- Ignasi Oliveras
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
- *Correspondence: Ignasi Oliveras and Alberto Fernández-Teruel, Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Autonomous University of Barcelona, 08913 Bellaterra, Barcelona, Spain ;
| | - Cristóbal Río-Álamos
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
| | - Toni Cañete
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
| | - Gloria Blázquez
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
| | - Esther Martínez-Membrives
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
| | - Osvaldo Giorgi
- Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, Department of Life and Environmental Sciences, University of CagliariCagliari, Italy
| | - Maria G. Corda
- Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, Department of Life and Environmental Sciences, University of CagliariCagliari, Italy
| | - Adolf Tobeña
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Institute of Neurosciences, Autonomous University of BarcelonaBarcelona, Spain
- *Correspondence: Ignasi Oliveras and Alberto Fernández-Teruel, Medical Psychology Unit, Department of Psychiatry and Forensic Medicine, School of Medicine, Autonomous University of Barcelona, 08913 Bellaterra, Barcelona, Spain ;
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Galatzer-Levy IR, Moscarello J, Blessing EM, Klein J, Cain CK, LeDoux JE. Heterogeneity in signaled active avoidance learning: substantive and methodological relevance of diversity in instrumental defensive responses to threat cues. Front Syst Neurosci 2014; 8:179. [PMID: 25309354 PMCID: PMC4173321 DOI: 10.3389/fnsys.2014.00179] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 09/05/2014] [Indexed: 11/13/2022] Open
Abstract
Individuals exposed to traumatic stressors follow divergent patterns including resilience and chronic stress. However, researchers utilizing animal models that examine learned or instrumental threat responses thought to have translational relevance for Posttraumatic Stress Disorder (PTSD) and resilience typically use central tendency statistics that assume population homogeneity. This approach potentially overlooks fundamental differences that can explain human diversity in response to traumatic stressors. The current study tests this assumption by identifying and replicating common heterogeneous patterns of response to signaled active avoidance (AA) training. In this paradigm, rats are trained to prevent an aversive outcome (shock) by performing a learned instrumental behavior (shuttling between chambers) during the presentation of a conditioned threat cue (tone). We test the hypothesis that heterogeneous trajectories of threat avoidance provide more accurate model fit compared to a single mean trajectory in two separate studies. Study 1 conducted 3 days of signaled AA training (n = 81 animals) and study 2 conducted 5 days of training (n = 186 animals). We found that four trajectories in both samples provided the strongest model fit. Identified populations included animals that acquired and retained avoidance behavior on the first day (Rapid Avoiders: 22 and 25%); those who never successfully acquired avoidance (Non-Avoiders; 20 and 16%); a modal class who acquired avoidance over 3 days (Modal Avoiders; 37 and 50%); and a population who demonstrated a slow pattern of avoidance, failed to fully acquire avoidance in study 1 and did acquire avoidance on days 4 and 5 in study 2 (Slow Avoiders; 22.0 and 9%). With the exception of the Slow Avoiders in Study 1, populations that acquired demonstrated rapid step-like increases leading to asymptotic levels of avoidance. These findings indicate that avoidance responses are heterogeneous in a way that may be informative for understanding both resilience and PTSD as well as the nature of instrumental behavior acquisition. Characterizing heterogeneous populations based on their response to threat cues would increase the accuracy and translatability of such models and potentially lead to new discoveries that explain diversity in instrumental defensive responses.
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Affiliation(s)
| | - Justin Moscarello
- Department of Arts and Sciences, Center for Neural Science, New York University New York, NY, USA
| | - Esther M Blessing
- Department of Psychiatry, New York University School of Medicine New York, NY, USA
| | - JoAnna Klein
- Department of Arts and Sciences, Center for Neural Science, New York University New York, NY, USA
| | - Christopher K Cain
- Department of Psychiatry, New York University School of Medicine New York, NY, USA ; Department of Arts and Sciences, Center for Neural Science, New York University New York, NY, USA ; Nathan Klein Institute Orangeburg, SC, USA
| | - Joseph E LeDoux
- Department of Arts and Sciences, Center for Neural Science, New York University New York, NY, USA ; Nathan Klein Institute Orangeburg, SC, USA
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Ursinus WW, Van Reenen CG, Reimert I, Bolhuis JE. Tail biting in pigs: blood serotonin and fearfulness as pieces of the puzzle? PLoS One 2014; 9:e107040. [PMID: 25188502 PMCID: PMC4154847 DOI: 10.1371/journal.pone.0107040] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 08/14/2014] [Indexed: 12/04/2022] Open
Abstract
Tail biting in pigs is a widespread problem in intensive pig farming. The tendency to develop this damaging behaviour has been suggested to relate to serotonergic functioning and personality characteristics of pigs. We investigated whether tail biting in pigs can be associated with blood serotonin and with their behavioural and physiological responses to novelty. Pigs (n = 480) were born in conventional farrowing pens and after weaning at four weeks of age they were either housed barren (B) or in straw-enriched (E) pens. Individual pigs were exposed to a back test and novel environment test before weaning, and after weaning to a novel object (i.e. bucket) test in an unfamiliar arena. A Principal Component Analysis on behaviours during the tests and salivary cortisol (novel object test only) revealed five factors for both housing systems, labeled ‘Early life exploration’, ‘Near bucket’, ‘Cortisol’, ‘Vocalizations & standing alert’, and ‘Back test activity’. Blood samples were taken at 8, 9 and 22 weeks of age to determine blood platelet serotonin. In different phases of life, pigs were classified as tail biter/non-tail biter based on tail biting behaviour, and as victim/non-victim based on tail wounds. A combination of both classifications resulted in four pig types: biters, victims, biter/victims, and neutrals. Generally, only in phases of life during which pigs were classified as tail biters, they seemed to have lower blood platelet serotonin storage and higher blood platelet uptake velocities. Victims also seemed to have lower blood serotonin storage. Additionally, in B housing, tail biters seemed to consistently have lower scores of the factor ‘Near bucket’, possibly indicating a higher fearfulness in tail biters. Further research is needed to elucidate the nature of the relationship between peripheral 5-HT, fearfulness and tail biting, and to develop successful strategies and interventions to prevent and reduce tail biting.
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Affiliation(s)
- Winanda W. Ursinus
- Adaptation Physiology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
- Animal behaviour & Welfare, Wageningen UR Livestock Research, Wageningen, The Netherlands
- * E-mail:
| | - Cornelis G. Van Reenen
- Animal behaviour & Welfare, Wageningen UR Livestock Research, Wageningen, The Netherlands
| | - Inonge Reimert
- Adaptation Physiology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - J. Elizabeth Bolhuis
- Adaptation Physiology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
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Genomes and phenomes of a population of outbred rats and its progenitors. Sci Data 2014; 1:140011. [PMID: 25977769 PMCID: PMC4381735 DOI: 10.1038/sdata.2014.11] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/12/2014] [Indexed: 01/31/2023] Open
Abstract
Finding genetic variants that contribute to phenotypic variation is one of the main challenges of modern genetics. We used an outbred population of rats (Heterogeneous Stock, HS) in a combined sequence-based and genetic mapping analysis to identify sequence variants and genes contributing to complex traits of biomedical relevance. Here we describe the sequences of the eight inbred progenitors of the HS and the variants that segregate between them. We report the genotyping of 1,407 HS rats, and the collection from 2,006 rats of 195 phenotypic measures that are relevant to models of anxiety, type 2 diabetes, hypertension and osteoporosis. We make available haplotype dosages for the 1,407 genotyped rats, since genetic mapping in the HS is best carried out by reconstructing each HS chromosome as a mosaic of the progenitor genomes. Finally, we have deposited an R object that makes it easy to incorporate our sequence data into any genetic study of HS rats. Our genetic data are available for both Rnor3.4 and Rnor5.0 rat assemblies.
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Knapp DJ, Daws LC, Overstreet DH. Behavioral Characteristics of Pharmacologically Selected Lines of Rats: Relevance to Depression. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/wjns.2014.43026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Baud A, Flint J, Fernandez-Teruel A, Consortium TRGSM. Identification of Genetic Variants Underlying Anxiety and Multiple Sclerosis in Heterogeneous Stock Rats. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/wjns.2014.43025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Estanislau C, Díaz-Morán S, Cañete T, Blázquez G, Tobeña A, Fernández-Teruel A. Context-dependent differences in grooming behavior among the NIH heterogeneous stock and the Roman high- and low-avoidance rats. Neurosci Res 2013; 77:187-201. [DOI: 10.1016/j.neures.2013.09.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 09/25/2013] [Accepted: 09/30/2013] [Indexed: 10/26/2022]
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Lichtenberg NT, Kashtelyan V, Burton AC, Bissonette GB, Roesch MR. Nucleus accumbens core lesions enhance two-way active avoidance. Neuroscience 2013; 258:340-6. [PMID: 24275320 DOI: 10.1016/j.neuroscience.2013.11.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 11/13/2013] [Accepted: 11/14/2013] [Indexed: 12/24/2022]
Abstract
The majority of work examining the nucleus accumbens core (NAc) has focused on functions pertaining to behaviors guided by appetitive outcomes. These studies have pointed to the NAc as being critical for motivating behavior toward desirable outcomes. For example, we have recently shown that lesions of the NAc impaired performance on a reward-guided decision-making task that required rats to choose between differently valued rewards. Unfortunately, much less is known about the role that the NAc plays in motivating behavior when aversive outcomes are predicted. To address this issue we asked if NAc lesions impact performance on a two-way active avoidance task in which rats must learn to shuttle back and forth in a behavioral training box in order to avoid a footshock predicted by an auditory tone. Although bilateral NAc lesions initially impaired reward-guided decision-making, we found that the same lesions improved acquisition and retention of two-way active avoidance.
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Affiliation(s)
- N T Lichtenberg
- Department of Psychology, University of Maryland, College Park, MD 20742, United States
| | - V Kashtelyan
- Department of Psychology, University of Maryland, College Park, MD 20742, United States
| | - A C Burton
- Department of Psychology, University of Maryland, College Park, MD 20742, United States; Program in Neuroscience and Cognitive Science, University of Maryland, College Park, MD 20742, United States
| | - G B Bissonette
- Department of Psychology, University of Maryland, College Park, MD 20742, United States
| | - M R Roesch
- Department of Psychology, University of Maryland, College Park, MD 20742, United States; Program in Neuroscience and Cognitive Science, University of Maryland, College Park, MD 20742, United States.
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Díaz-Morán S, Palència M, Mont-Cardona C, Cañete T, Blázquez G, Martínez-Membrives E, López-Aumatell R, Sabariego M, Donaire R, Morón I, Torres C, Martínez-Conejero JA, Tobeña A, Esteban FJ, Fernández-Teruel A. Gene expression in hippocampus as a function of differential trait anxiety levels in genetically heterogeneous NIH-HS rats. Behav Brain Res 2013; 257:129-39. [PMID: 24095878 DOI: 10.1016/j.bbr.2013.09.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 09/20/2013] [Accepted: 09/23/2013] [Indexed: 02/07/2023]
Abstract
To identify genes involved in the development/expression of anxiety/fear, we analyzed the gene expression profile in the hippocampus of genetically heterogeneous NIH-HS rats. The NIH-HS rat stock is a unique genetic resource for the fine mapping of quantitative trait loci (QTLs) to very small genomic regions, due to the high amount of genetic recombinants accumulated along more than 50 breeding generations, and for the same reason it can be expected that those genetically heterogeneous rats should be especially useful for studying differential gene expression as a function of anxiety, fearfulness or other complex traits. We selected high- and low-anxious NIH-HS rats according to the number of avoidance responses they performed in a single 50-trial session of the two-way active avoidance task. Rats were also tested in unconditioned anxiety/fearfulness tests, i.e. the elevated zero-maze and a "novel-cage activity" test. Three weeks after behavioral testing, the hippocampus was dissected and prepared for the microarray study. There appeared 29 down-regulated and 37 up-regulated SNC-related genes (fold-change>|2.19|, FDR<0.05) in the "Low-anxious" vs. the "High-anxious" group. Regression analyses (stepwise) revealed that differential expression of some genes could be predictive of anxiety/fear responses. Among those genes for which the present results suggest a link with individual differences in trait anxiety, nine relevant genes (Avpr1b, Accn3, Cd74, Ltb, Nrg2, Oprdl1, Slc10a4, Slc5a7 and RT1-EC12), tested for validation through qRT-PCR, have either neuroendocrinological or neuroinmunological/inflammation-related functions, or have been related with the hippocampal cholinergic system, while some of them have also been involved in the modulation of anxiety or stress-related (neurobiological and behavioral) responses (i.e. Avpr1b, Oprdl1). The present work confirms the usefulness of NIH-HS rats as a good animal model for research on the neurogenetic basis or mechanisms involved in anxiety and/or fear, and suggest that some MHC-(neuroinmunological/inflammation)-related pathways, as well as the cholinergic system within the hippocampus, may play a role in shaping individual differences in trait anxiety.
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Affiliation(s)
- Sira Díaz-Morán
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, School of Medicine, Autonomous University of Barcelona, Barcelona, Spain
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Díaz-Morán S, Palència M, Mont-Cardona C, Cañete T, Blázquez G, Martínez-Membrives E, López-Aumatell R, Sabariego M, Donaire R, Morón I, Torres C, Martínez-Conejero JA, Tobeña A, Esteban FJ, Fernández-Teruel A. Gene expression in amygdala as a function of differential trait anxiety levels in genetically heterogeneous NIH-HS rats. Behav Brain Res 2013; 252:422-31. [PMID: 23777796 DOI: 10.1016/j.bbr.2013.05.066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/07/2013] [Accepted: 05/10/2013] [Indexed: 12/12/2022]
Abstract
To identify genes involved in anxiety/fear traits, we analyzed the gene expression profile in the amygdala of genetically heterogeneous NIH-HS rats. The NIH-HS rat stock has revealed to be a unique genetic resource for the fine mapping of Quantitative Trait Loci (QTLs) to very small genomic regions, due to the high amount of genetic recombinants accumulated along more than 50 breeding generations, and for the same reason it can be expected that those genetically heterogeneous rats should be especially useful for studying differential gene expression as a function of anxiety-(or other)-related traits. We selected high- and low-anxious NIH-HS rats differing in their number of avoidances in a single 50-trial session of the two-way active avoidance task. Rats were also tested in unconditioned anxiety tests (e.g., elevated zero-maze). Three weeks after behavioural testing, the amygdala was dissected and prepared for the microarray study. There appeared 6 significantly down-regulated and 28 up-regulated genes (fold-change >|2|, FDR<0.05) between the low- and high-anxious groups, with central nervous system-related functions. Regression analyses (stepwise) revealed that differential expression of some genes could be predictive of anxiety/fear responses. Among those genes for which the present results suggest a link with individual differences in trait anxiety, six relevant genes were examined with qRT-PCR, four of which (Ucn3, Tacr3, H2-M9 and Arr3) were validated. Remarkably, some of them are characterized by sharing known functions related with hormonal HPA-axis responses to (and/or modulation of) stress, anxiety or fear, and putative involvement in related neurobehavioural functions. The results confirm the usefulness of NIH-HS rats as a good animal model for research on the neurogenetic basis of anxiety and fear, while suggesting the involvement of some neuropeptide/neuroendocrine pathways on the development of differential anxiety profiles.
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Affiliation(s)
- Sira Díaz-Morán
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, School of Medicine, Universidad Autónoma de Barcelona, Barcelona, Spain.
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28
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Ursinus WW, Bolhuis JE, Zonderland JJ, Rodenburg TB, de Souza AS, Koopmanschap RE, Kemp B, Korte-Bouws GAH, Korte SM, van Reenen CG. Relations between peripheral and brain serotonin measures and behavioural responses in a novelty test in pigs. Physiol Behav 2013; 118:88-96. [PMID: 23685231 DOI: 10.1016/j.physbeh.2013.05.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/02/2013] [Accepted: 05/06/2013] [Indexed: 11/16/2022]
Abstract
Pigs differ in their behavioural responses towards environmental challenges. Individual variation in maladaptive responses such as tail biting, may partly originate from underlying biological characteristics related to (emotional) reactivity to challenges and serotonergic system functioning. Assessing relations between behavioural responses and brain and blood serotonin parameters may help in understanding susceptibility to the development of maladaptive responses. The objective of the current study was, therefore, to assess the relationship between the pigs' serotonergic parameters measured in both blood and brain, and the behaviour of pigs during a novelty test. Pigs (n=31) were subjected to a novelty test at 11weeks of age, consisting of 5-min novel environment exposure after which a novel object (a bucket) was introduced for 5min. Whole blood serotonin, platelet serotonin level, and platelet serotonin uptake were determined at 13weeks of age. Levels of serotonin, its metabolite and serotonin turnover were determined at 19weeks of age in the frontal cortex, hypothalamus and hippocampus. The behaviour of the pigs was different during exposure to a novel object compared to the novel environment only, with more fear-related behaviours exhibited during novel object exposure. Platelet serotonin level and brain serotonergic parameters in the hippocampus were interrelated. Notably, the time spent exploring the test arena was significantly correlated with both platelet serotonin level and right hippocampal serotonin activity (turnover and concentration). In conclusion, the existence of an underlying biological trait - possibly fearfulness - may be involved in the pig's behavioural responses toward environmental challenges, and this is also reflected in serotonergic parameters.
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Affiliation(s)
- Winanda W Ursinus
- Wageningen University, Department of Animal Sciences, Adaptation Physiology Group, P.O. Box 338, 6700 AH, Wageningen, The Netherlands.
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Palència M, Díaz-Morán S, Mont-Cardona C, Cañete T, Blázquez G, Martínez-Membrives E, López-Aumatell R, Tobeña A, Fernández-Teruel A. Helplessness-like escape deficits of NIH-HS rats predict passive behavior in the forced swimming test: Relevance for the concurrent validity of rat models of depression. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/wjns.2013.32012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Díaz-Morán S, Martínez-Membrives E, López-Aumatell R, Cañete T, Blázquez G, Palencia M, Mont-Cardona C, Estanislau C, Tobeña A, Fernández-Teruel A. What can we learn on rodent fearfulness/anxiety from the genetically heterogeneous NIH-HS rat stock? ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojpsych.2013.32022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
To maximize their chances of survival, animals need to rapidly and efficiently respond to aversive situations. These responses can be classified as active or passive and depend on the specific nature of threats, but also on individual fear coping styles. In this study, we show that the control of excitatory and inhibitory brain neurons by type-1 cannabinoid (CB₁) receptors is a key determinant of fear coping strategies in mice. In classical fear conditioning, a switch between initially predominant passive fear responses (freezing) and active behaviors (escape attempts and risk assessment) develops over time. Constitutive genetic deletion of CB₁ receptors in CB₁⁻/⁻ mice disrupted this pattern by favoring passive responses. This phenotype can be ascribed to endocannabinoid control of excitatory neurons, because it was reproduced in conditional mutant mice lacking CB₁ receptors from cortical glutamatergic neurons. CB₁ receptor deletion from GABAergic brain neurons led to the opposite phenotype, characterized by the predominance of active coping. The CB₁ receptor agonist Δ⁹-tetrahydrocannabinol exerted a biphasic control of fear coping strategies, with lower and higher doses favoring active and passive responses, respectively. Finally, viral re-expression of CB₁ receptors in the amygdala of CB₁⁻/⁻ mice restored the normal switch between the two coping strategies. These data strongly suggest that CB₁ receptor signaling bimodally controls the spontaneous adoption of active or passive coping strategies in individuals. This primary function of the endocannabinoid system in shaping individual behavioral traits should be considered when studying the mechanisms of physiological and pathological fear.
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Díaz-Morán S, Palència M, Mont-Cardona C, Cañete T, Blázquez G, Martínez-Membrives E, López-Aumatell R, Tobeña A, Fernández-Teruel A. Coping style and stress hormone responses in genetically heterogeneous rats: comparison with the Roman rat strains. Behav Brain Res 2011; 228:203-10. [PMID: 22178313 DOI: 10.1016/j.bbr.2011.12.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 11/27/2011] [Accepted: 12/02/2011] [Indexed: 01/22/2023]
Abstract
The purpose of the present study was to evaluate for the first time the stress-induced hypothalamus-pituitary-adrenal (HPA), adrenocorticotropic hormone (ACTH), corticosterone and prolactin responses of the National Institutes of Health genetically heterogeneous rat stock (N/Nih-HS rats) in comparison with responses of the relatively high and low stress-prone Roman Low- (RLA-I) and High-Avoidance (RHA-I) rat strains. The same rats were also compared (experiment 1) with respect to their levels of unconditioned anxiety (elevated zero-maze test), novelty-induced exploratory behavior, conditioned fear and two-way active avoidance acquisition. In experiment 2, naive rats from these three strains/stocks were evaluated for "depressive-like" behavior in the forced swimming test. N/Nih-HS and RLA-I rats showed significantly higher post-stress ACTH, corticosterone and prolactin levels than RHA-I rats. N/Nih-HS rats also presented the highest context-conditioned freezing responses, extremely poor two-way avoidance acquisition and very low novelty-induced exploratory behavior. Experiment 2 showed that, compared to RHA-I rats, N/Nih-HS and RLA-I rats displayed significantly less struggling (escape-directed) and increased immobility responses in the forced swimming test. Factor analysis of data from experiment 1 showed associations among behavioral and hormonal responses, with a first factor comprising high loadings of elevated zero-maze variables and lower loadings of conditioned fear, two-way avoidance acquisition and hormonal measures, while a second factor mainly grouped conditioned fear and two-way avoidance acquisition with novelty-induced exploration and post-stress prolactin. Thus, regarding their anxiety/fearfulness, passive coping style, "depressive-like" and stress-induced hormonal responses the N/Nih-HS rats resemble the phenotype profiles of the relatively high-anxious and stress-prone RLA-I rat strain.
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Affiliation(s)
- Sira Díaz-Morán
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, School of Medicine, Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain
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López-Aumatell R, Martínez-Membrives E, Vicens-Costa E, Cañete T, Blázquez G, Mont-Cardona C, Johannesson M, Flint J, Tobeña A, Fernández-Teruel A. Effects of environmental and physiological covariates on sex differences in unconditioned and conditioned anxiety and fear in a large sample of genetically heterogeneous (N/Nih-HS) rats. Behav Brain Funct 2011; 7:48. [PMID: 22118015 PMCID: PMC3254066 DOI: 10.1186/1744-9081-7-48] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 11/25/2011] [Indexed: 11/17/2022] Open
Abstract
Physiological and environmental variables, or covariates, can account for an important portion of the variability observed in behavioural/physiological results from different laboratories even when using the same type of animals and phenotyping procedures. We present the results of a behavioural study with a sample of 1456 genetically heterogeneous N/Nih-HS rats, including males and females, which are part of a larger genome-wide fine-mapping QTL (Quantitative Trait Loci) study. N/Nih-HS rats have been derived from 8 inbred strains and provide very small distance between genetic recombinations, which makes them a unique tool for fine-mapping QTL studies. The behavioural test battery comprised the elevated zero-maze test for anxiety, novel-cage (open-field like) activity, two-way active avoidance acquisition (related to conditioned anxiety) and context-conditioned freezing (i.e. classically conditioned fear). Using factorial analyses of variance (ANOVAs) we aimed to analyse sex differences in anxiety and fear in this N/Nih-HS rat sample, as well as to assess the effects of (and interactions with) other independent factors, such as batch, season, coat colour and experimenter. Body weight was taken as a quantitative covariate and analysed by covariance analysis (ANCOVA). Obliquely-rotated factor analyses were also performed separately for each sex, in order to evaluate associations among the most relevant variables from each behavioural test and the common dimensions (i.e. factors) underlying the different behavioural responses. ANOVA analyses showed a consistent pattern of sex effects, with females showing less signs of anxiety and fear than males across all tests. There were also significant main effects of batch, season, colour and experimenter on almost all behavioural variables, as well as "sex × batch", "sex × season" and "sex × experimenter" interactions. Body weight showed significant effects in the ANCOVAs of most behavioural measures, but sex effects were still present in spite of (and after controlling for) these "body weight" effects. Factor analyses of relevant variables from each test showed a two-fold factor structure in both sexes, with the first factor mainly representing anxiety and conditioned fear in males, while in females the first factor was dominated by loadings of activity measures. Thus, besides showing consistent sex differences in anxiety-, fear- and activity-related responses in N/Nih-HS rats, the present study shows that females' behaviour is predominantly influenced by activity while males are more influenced by anxiety. Moreover, the results point out that, besides "sex" effects, physiological variables such as colour and body weight, and environmental factors as batch/season or "experimenter", have to be taken into account in both behavioural and quantitative genetic studies because of their demonstrated influences on phenotypic outcomes.
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