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Headley DB, Weinberger NM. Relational associative learning induces cross-modal plasticity in early visual cortex. Cereb Cortex 2015; 25:1306-18. [PMID: 24275832 PMCID: PMC4397573 DOI: 10.1093/cercor/bht325] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Neurobiological theories of memory posit that the neocortex is a storage site of declarative memories, a hallmark of which is the association of two arbitrary neutral stimuli. Early sensory cortices, once assumed uninvolved in memory storage, recently have been implicated in associations between neutral stimuli and reward or punishment. We asked whether links between neutral stimuli also could be formed in early visual or auditory cortices. Rats were presented with a tone paired with a light using a sensory preconditioning paradigm that enabled later evaluation of successful association. Subjects that acquired this association developed enhanced sound evoked potentials in their primary and secondary visual cortices. Laminar recordings localized this potential to cortical Layers 5 and 6. A similar pattern of activation was elicited by microstimulation of primary auditory cortex in the same subjects, consistent with a cortico-cortical substrate of association. Thus, early sensory cortex has the capability to form neutral stimulus associations. This plasticity may constitute a declarative memory trace between sensory cortices.
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Affiliation(s)
- Drew B Headley
- Center for the Neurobiology of Learning and Memory, Department of Neurobiology and Behavior, University of California, Irvine, CA 92697-3800, USA
| | - Norman M Weinberger
- Center for the Neurobiology of Learning and Memory, Department of Neurobiology and Behavior, University of California, Irvine, CA 92697-3800, USA
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Gerber B, Yarali A, Diegelmann S, Wotjak CT, Pauli P, Fendt M. Pain-relief learning in flies, rats, and man: basic research and applied perspectives. Learn Mem 2014; 21:232-52. [PMID: 24643725 PMCID: PMC3966540 DOI: 10.1101/lm.032995.113] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Memories relating to a painful, negative event are adaptive and can be stored for a lifetime to support preemptive avoidance, escape, or attack behavior. However, under unfavorable circumstances such memories can become overwhelmingly powerful. They may trigger excessively negative psychological states and uncontrollable avoidance of locations, objects, or social interactions. It is therefore obvious that any process to counteract such effects will be of value. In this context, we stress from a basic-research perspective that painful, negative events are "Janus-faced" in the sense that there are actually two aspects about them that are worth remembering: What made them happen and what made them cease. We review published findings from fruit flies, rats, and man showing that both aspects, respectively related to the onset and the offset of the negative event, induce distinct and oppositely valenced memories: Stimuli experienced before an electric shock acquire negative valence as they signal upcoming punishment, whereas stimuli experienced after an electric shock acquire positive valence because of their association with the relieving cessation of pain. We discuss how memories for such punishment- and relief-learning are organized, how this organization fits into the threat-imminence model of defensive behavior, and what perspectives these considerations offer for applied psychology in the context of trauma, panic, and nonsuicidal self-injury.
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Affiliation(s)
- Bertram Gerber
- Leibniz Institut für Neurobiologie (LIN), Abteilung Genetik von Lernen und Gedächtnis, 39118 Magdeburg, Germany
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Quinn JJ, Skipper RA, Claflin DI. Infant stress exposure produces persistent enhancement of fear learning across development. Dev Psychobiol 2013; 56:1008-16. [PMID: 24264998 DOI: 10.1002/dev.21181] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 10/27/2013] [Indexed: 01/03/2023]
Abstract
In recent years, it has become increasingly clear that early life stress experiences persistently impact subsequent physiological, cognitive, and emotional responses. In cases of trauma, these early experiences can result in anxiety disorders such as phobias and posttraumatic stress disorder. In the present paper, we examined the effects of infant footshock stress exposure at postnatal day (PND) 17 on subsequent contextual fear conditioning at postnatal days 18 (Experiment 1), 24 (Experiment 2), or 90 (Experiment 3). In each experiment, PND17 footshock stress exposure enhanced later fear conditioning, indicating that the stress enhancement of fear learning (SEFL) persists throughout development. Memory for the original stress exposure context was gradually forgotten, with significant fear expression evident at PND20, and a complete lack of fear expression in that same context at PND90. These data suggest that the stress-enhancing component of infant fear learning is dissociable from the infant contextual fear memory per se. In other words, early life stress produces persistent effects on subsequent cognition that are independent of the memory for that early life event.
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Affiliation(s)
- Jennifer J Quinn
- Department of Psychology, Center for Neuroscience and Behavior, Miami University, 100 Psychology Building, 90N. Patterson Ave., Oxford, OH, 45056.
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Ruiz-Diaz M, Torrero C, Regalado M, Salas M. Perinatal undernourishment and handling: effects on olfactory discrimination in the newborn rat. Nutr Neurosci 2013. [DOI: 10.1179/147683010x12611460764408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Kramer K, van de Weerd H, Mulder A, Van Heijningen C, Baumans V, Remie R, Voss HP, van Zutphen BFM. Effect of conditioning on the increase of heart rate and body temperature provoked by handling in the mouse. Altern Lab Anim 2013; 32 Suppl 1A:177-81. [PMID: 23577455 DOI: 10.1177/026119290403201s29] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
To assess the effect of procedures on animal welfare, various physiological parameters, such as body weight, hormone levels in plasma and/or urine, heart rate (HR), blood pressure and body temperature (BT), can be used. When measuring physiological parameters with techniques involving restraint of the animals, the results must be interpreted with caution, since restraint itself may have an effect on those parameters. Radio-telemetry, using an implantable transmitter, provides a way to obtain more accurate and reliable physiological measurements from freely moving animals in their own environment. In this study, we have used radio-telemetry to investigate the influence of conditioning on the increase of HR and BT as provoked by handling of mice. It was found that, after a conditioning period of 12 days, the increase of HR due to handling was significantly reduced.
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Affiliation(s)
- Klaas Kramer
- Department of Health, Safety and the Environment, Free University, Amsterdam, The Netherlands.
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Schreurs BG, Burhans LB, Smith-Bell CA, Mrowka SW, Wang D. Ontogeny of trace eyeblink conditioning to shock-shock pairings in the rat pup. Behav Neurosci 2013; 127:114-20. [PMID: 23244289 PMCID: PMC3939836 DOI: 10.1037/a0031298] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rats are responsive to shock from an early age, but eyeblink conditioning to a tone-conditioned stimulus (conditional stimulus; CS) paired with a shock-unconditioned stimulus (US) does not emerge until postnatal Day 20 (P20). More generalized postural responses such as conditioned freezing can occur at P16. Using the same periorbital shock as both the CS and US in a US-US conditioning paradigm previously shown to be effective in adult animals, we found that shock-shock pairings with a 200-ms trace interval resulted in eyeblink conditioning in younger animals than previously thought. Some rat pups showed conditioned eyeblink responses as early as P12, and by P18, conditioned responses were fully developed in all animals. Unpaired control subjects confirmed that responding in paired subjects was associative. Although many stimuli can act as a CS in adults, the advantage of using US-US pairings is that responses to the first US ensure young rat pups are capable of detecting the stimulus-something that may not be true when auditory or visual stimuli are used early in the development of altricial animals. The US-US pairing paradigm could be used to study the ontogeny and neural substrates of learning and memory before other sensory systems mature, and evaluate learning and memory in animal models of early developmental disorders.
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Affiliation(s)
- Bernard G Schreurs
- Blanchette Rockefeller Neurosciences Institute, 8 Medical Center Drive, West Virginia University, Morgantown, WV 26505, USA.
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Freeman JH, Duffel JW. Eyeblink conditioning using cochlear nucleus stimulation as a conditioned stimulus in developing rats. Dev Psychobiol 2009; 50:640-6. [PMID: 18688803 DOI: 10.1002/dev.20331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Previous studies demonstrated that the development of auditory conditioned stimulus (CS) input to the cerebellum may be a neural mechanism underlying the ontogenetic emergence of eyeblink conditioning in rats. The current study investigated the role of developmental changes in the projections of the cochlear nucleus (CN) in the ontogeny of eyeblink conditioning using electrical stimulation of the CN as a CS. Rat pups were implanted with a bipolar stimulating electrode in the CN and given six 100-trial training sessions with a 300 ms stimulation train in the CN paired with a 10 ms periorbital shock unconditioned stimulus (US) on postnatal days (P) 17-18 or 24-25. Control groups were given unpaired presentations of the CS and US. Rats in both age groups that received paired training showed significant increases in eyeblink conditioned responses across training relative to the unpaired groups. The rats trained on P24-25, however, showed stronger conditioning relative to the group trained on P17-18. Rats with missed electrodes in the inferior cerebellar peduncle or in the cerebellar cortex did not show conditioning. The findings suggest that developmental changes in the CN projections to the pons, inferior colliculus, or medial auditory thalamus may be a neural mechanism underlying the ontogeny of auditory eyeblink conditioning.
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Affiliation(s)
- John H Freeman
- Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, Iowa 52242, USA.
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Shionoya K, Moriceau S, Lunday L, Miner C, Roth TL, Sullivan RM. Development switch in neural circuitry underlying odor-malaise learning. Learn Mem 2006; 13:801-8. [PMID: 17101877 PMCID: PMC1783635 DOI: 10.1101/lm.316006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Fetal and infant rats can learn to avoid odors paired with illness before development of brain areas supporting this learning in adults, suggesting an alternate learning circuit. Here we begin to document the transition from the infant to adult neural circuit underlying odor-malaise avoidance learning using LiCl (0.3 M; 1% of body weight, ip) and a 30-min peppermint-odor exposure. Conditioning groups included: Paired odor-LiCl, Paired odor-LiCl-Nursing, LiCl, and odor-saline. Results showed that Paired LiCl-odor conditioning induced a learned odor aversion in postnatal day (PN) 7, 12, and 23 pups. Odor-LiCl Paired Nursing induced a learned odor preference in PN7 and PN12 pups but blocked learning in PN23 pups. 14C 2-deoxyglucose (2-DG) autoradiography indicated enhanced olfactory bulb activity in PN7 and PN12 pups with odor preference and avoidance learning. The odor aversion in weanling aged (PN23) pups resulted in enhanced amygdala activity in Paired odor-LiCl pups, but not if they were nursing. Thus, the neural circuit supporting malaise-induced aversions changes over development, indicating that similar infant and adult-learned behaviors may have distinct neural circuits.
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Affiliation(s)
- Kiseko Shionoya
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Stephanie Moriceau
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Lauren Lunday
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Cathrine Miner
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Tania L. Roth
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
| | - Regina M. Sullivan
- Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019, USA
- Corresponding author.E-mail ; fax (405) 325-2699
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Rosenkranz JA, Buffalari DM, Grace AA. Opposing influence of basolateral amygdala and footshock stimulation on neurons of the central amygdala. Biol Psychiatry 2006; 59:801-11. [PMID: 16373067 DOI: 10.1016/j.biopsych.2005.09.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2005] [Revised: 07/14/2005] [Accepted: 09/22/2005] [Indexed: 12/12/2022]
Abstract
BACKGROUND The basolateral complex (BLA) and the central nucleus of the amygdala (CeA) are believed to mediate the expression of affective responses. After affective learning, conditioned stimulus-related information is thought to be conveyed from the BLA to the CeA; the medial CeA (Cem), in turn, projects to hypothalamic and brainstem structures involved with induction of affective responses. Although the conditioned stimulus and unconditioned stimulus both evoke affective responses, the precise response often differs. It is unknown whether this difference is represented by distinct activity patterns of single Cem neurons. Furthermore, the nature of the interaction between the BLA and Cem is unknown. METHODS Using in vivo extracellular and intracellular recordings, we examined how the BLA affects the Cem and compared this with effects induced by footshock (unconditioned stimulus) in the same neurons. RESULTS Our results demonstrate that, contrary to conventional views, BLA stimulation primarily inhibits Cem neurons by a polysynaptic circuit, and show that single Cem neurons respond to both BLA input and footshock in an opposite manner. CONCLUSIONS These results demonstrate the predominantly inhibitory nature of the BLA-Cem interaction. These data further demonstrate the distinct cellular events that might lead to differential modulation of conditioned and unconditioned affective responses.
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Affiliation(s)
- J Amiel Rosenkranz
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Zhang WN, Murphy CA, Feldon J. Behavioural and cardiovascular responses during latent inhibition of conditioned fear: measurement by telemetry and conditioned freezing. Behav Brain Res 2004; 154:199-209. [PMID: 15302126 DOI: 10.1016/j.bbr.2004.02.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 02/10/2004] [Accepted: 02/11/2004] [Indexed: 10/26/2022]
Abstract
This study assessed freezing behaviour and cardiovascular responses during the expression of latent inhibition of conditioned fear. Animals that were either repeatedly preexposed (PE) to a tone conditioned stimulus (CS) or naive to the tone (non-preexposed; NPE) subsequently experienced three presentations of the tone paired with footshock. Animals were tested 24 h later in the context of the footshock chamber, and on the following day, in the presence of the tone CS. Changes in heart rate and blood pressure were recorded by radio-telemetry. The PE rats spent more time freezing to the conditioned contextual cues and exhibited higher blood pressures during the last half of the context test session than did the NPE animals. During the tone test, the PE rats exhibited less conditioned freezing to the tone CS compared with the NPE animals, i.e. expression of the latent inhibition. This behavioural effect was associated with a significant increase in heart rate, but not blood pressure, in the PE but not the NPE animals. Our results suggest that the increased blood pressures of the PE rats during the context test directly reflect their greater fear of the conditioning context. In contrast, the increased heart rate response but decreased freezing shown by PE rats in response to the tone CS may be due to the fact that lower stress levels (e.g. PE condition) elicit sympathetically-mediated increases in heart rate, whereas higher stress levels (e.g. NPE condition) activate both sympathetic and parasympathetic systems, thus eliminating any CS-induced increase in heart rate in the NPE rats.
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Affiliation(s)
- Wei-Ning Zhang
- Behavioral Neurobiology Laboratory, The Swiss Federal Institute of Technology Zurich, Schorenstrasse 16, CH-8603 Schwerzenbach, Switzerland
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Bouwknecht JA, Hijzen TH, van der Gugten J, Dirks A, Maes RA, Hen R, Geyer MA, Olivier B. Startle responses, heart rate, and temperature in 5-HT1B receptor knockout mice. Neuroreport 2000; 11:4097-102. [PMID: 11192635 DOI: 10.1097/00001756-200012180-00037] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Relative to wildtype mice, mice lacking 5-HT1B receptors (5-HT1B KO) exhibit exaggerated heart rate and body temperature responses to environmental stimuli. In contrast, acoustic startle reactivity is reduced in 5-HT1B KO mice. We combined heart rate and temperature measurement with startle response paradigms in order to elucidate this apparent contradiction. Habituation and footshock-induced sensitization paradigms modulate startle reactivity. Reduced startle reactivity and unaltered habituation in 5-HT1B KO mice were replicated. Heart rate and temperature were unaffected by startle stimuli, but increased markedly in response to transportation and handling procedures. Footshocks caused a mild startle-sensitization and tachycardia in both genotypes. The physiological hyper-reactivity in 5-HT1B KO mice is a subtle phenotypic difference that contrasts with the phenotypic decrease in startle reactivity.
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Affiliation(s)
- J A Bouwknecht
- Department of Psychopharmacology, Faculty of Pharmacy, Utrecht University, The Netherlands
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13
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Abstract
After a few pairings of a threatening stimulus with a formerly neutral cue, animals and humans will experience a state of conditioned fear when only the cue is present. Conditioned fear provides a critical survival-related function in the face of threat by activating a range of protective behaviors. The present review summarizes and compares the results of different laboratories investigating the neuroanatomical and neurochemical basis of conditioned fear, focusing primarily on the behavioral models of freezing and fear-potentiated startle in rats. On the basis of these studies, we describe the pathways mediating and modulating fear. We identify several key unanswered questions and discuss possible implications for the understanding of human anxiety disorders.
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Affiliation(s)
- M Fendt
- Tierphysiologie, Universität Tübingen, Germany.
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Abstract
This series of experiments was designed to reexamine the ontogenetic emergence of the fear-potentiated startle response in rats. Previous results (Hunt, Richardson, & Campbell, 1994) indicated that potentiated startle to a light conditioned stimulus (CS) paired with an acoustic unconditioned stimulus (US) was not observed until 30 days of age. In the present experiments, subjects were given pairings of a light CS with a brief footshock unconditioned stimulus (US) and were tested for fear-potentiated startle 24 hr later. Subjects 23 and 30 days of age exhibited significant potentiated responding in the presence of the light, while 17-and 20-day-olds did not. Subjects 17 days of age did reliably express conditioned decreases in heart rate to the light at the 24-hr test. The failure to observe fear-potentiated startle at the youngest age was shown not to be due to a general disruption of conditioned fear responding by either (a) pretest startle stimulus presentations or (b) contextual characteristics of the startle testing apparatus. The capacity to express fear through a potentiated startle response develops later than the capacity for other defensive responses in the rat.
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Affiliation(s)
- P S Hunt
- Department of Psychology, College of William & Mary, Williamsburg, VA 23187-8795, USA
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Abstract
It is generally recognized that during development the capacity to express learning in terms of changes in somatomotor activity is evident earlier than the capacity for learned changes in autonomic responding (e.g., heart rate). In this series of experiments, findings indicate that changes in heart rate to a visual conditioned stimulus (CS) paired with a footshock unconditioned stimulus (US) can be observed as early in development in the rat as freezing responses. However, cardiac responses are inhibited from being expressed by preweanlings (but not adults) during CS-US pairings, the time when heart rate responses are often measured. This inhibition appears to arise from US exposure, and dissipates completely within 2 hr of training. These findings are discussed with respect to developmental changes in US-evoked autonomic arousal and response system dissociations.
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Hunt PS, Richardson R, Hess MF, Campbell BA. Emergence of conditioned cardiac responses to an olfactory CS paired with an acoustic startle UCS during development: Form and autonomic origins. Dev Psychobiol 1997. [DOI: 10.1002/(sici)1098-2302(199703)30:2<151::aid-dev6>3.0.co;2-p] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Blanc J, Baudrie V, Tulen J, Ponchon P, Gaudet E, Elghozi JL. Social isolation affects the pattern of cardiovascular responses to repetitive acoustic startle stimuli. Clin Exp Pharmacol Physiol 1997; 24:40-5. [PMID: 9043804 DOI: 10.1111/j.1440-1681.1997.tb01781.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
1. The aim of this study was to investigate the cardiovascular responses to repetitive alerting stimuli in rats subjected to intermittent social isolation, in comparison with animals housed in pairs. 2. Ten male Wistar rats were implanted with a blood pressure (BP) telemetric system and enrolled in a randomized cross-over study design. Rats were either isolated or housed in pairs for an 8 day period. At the end of each period, the animals were exposed to five acoustic stimuli (110 dB at 15 kHz, 80 ms after the impact, duration 700 ms) at 60 s intervals. For each stimulus, maximal BP and heart rate (HR) responses were calculated. BP variability was analysed in the frequency domain before the first stimulation using power spectral analysis. 3. Isolated animals showed more faster breathing (1.71 vs 1.42 Hz in the paired condition). The 0.4 Hz zone of the systolic BP spectral power was not significantly affected by isolation (1.11 vs 0.85 mmHg2). BP and HR resting levels of isolated rats (121 mmHg for the systolic BP and 290 b.p.m.) were similar to those of animals housed in pairs (119 mmHg for the systolic BP and 279 b.p.m.). 4. The first acoustic stimulus caused a brief rise in BP of a comparable amplitude in both conditions (24 +/- 2 mmHg). A biphasic HR response was also observed, but the delayed bradycardia was more marked during isolation (37 vs 6 b.p.m. decrease). BP and HR levels were restored within 20 s. 5. Interestingly, BP responses were progressively attenuated to become negligible at the fifth presentation (1 mmHg) in the isolated state, while during the paired state a substantial pressor response (13 mmHg) after each successive stimulus was maintained. Paired rats exhibited a constant HR profile across the trials, consisting in a slight HR increase (< 5 b.p.m.), concomitant with the BP elevation, followed by a delayed bradycardia (around 15 b.p.m.). HR profiles in the isolated condition differed markedly: HR rises increased in magnitude with the trial number, reaching 30 b.p.m. after the 5th trial. 6. Spontaneous BP and HR increases, as observed throughout the experiment were quantitatively small (6 mmHg and < 10 b.p.m.) in the two conditions. 7. These data indicate that isolation markedly affects the BP habituation profile to repetitive alerting stimuli. The BP response attenuation might unmask a tachycardic response. Alternatively, the amplified tachycardia following the latter stimuli might express sensitization to the conditioned fear resulting from isolation.
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Affiliation(s)
- J Blanc
- Pharmacologie, CNRS URA 1482, Faculté de Médecine Necker, Paris, France
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