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Lipp HP, Krackow S, Turkes E, Benner S, Endo T, Russig H. IntelliCage: the development and perspectives of a mouse- and user-friendly automated behavioral test system. Front Behav Neurosci 2024; 17:1270538. [PMID: 38235003 PMCID: PMC10793385 DOI: 10.3389/fnbeh.2023.1270538] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/18/2023] [Indexed: 01/19/2024] Open
Abstract
IntelliCage for mice is a rodent home-cage equipped with four corner structures harboring symmetrical double panels for operant conditioning at each of the two sides, either by reward (access to water) or by aversion (non-painful stimuli: air-puffs, LED lights). Corner visits, nose-pokes and actual licks at bottle-nipples are recorded individually using subcutaneously implanted transponders for RFID identification of up to 16 adult mice housed in the same home-cage. This allows for recording individual in-cage activity of mice and applying reward/punishment operant conditioning schemes in corners using workflows designed on a versatile graphic user interface. IntelliCage development had four roots: (i) dissatisfaction with standard approaches for analyzing mouse behavior, including standardization and reproducibility issues, (ii) response to handling and housing animal welfare issues, (iii) the increasing number of mouse models had produced a high work burden on classic manual behavioral phenotyping of single mice. and (iv), studies of transponder-chipped mice in outdoor settings revealed clear genetic behavioral differences in mouse models corresponding to those observed by classic testing in the laboratory. The latter observations were important for the development of home-cage testing in social groups, because they contradicted the traditional belief that animals must be tested under social isolation to prevent disturbance by other group members. The use of IntelliCages reduced indeed the amount of classic testing remarkably, while its flexibility was proved in a wide range of applications worldwide including transcontinental parallel testing. Essentially, two lines of testing emerged: sophisticated analysis of spontaneous behavior in the IntelliCage for screening of new genetic models, and hypothesis testing in many fields of behavioral neuroscience. Upcoming developments of the IntelliCage aim at improved stimulus presentation in the learning corners and videotracking of social interactions within the IntelliCage. Its main advantages are (i) that mice live in social context and are not stressfully handled for experiments, (ii) that studies are not restricted in time and can run in absence of humans, (iii) that it increases reproducibility of behavioral phenotyping worldwide, and (iv) that the industrial standardization of the cage permits retrospective data analysis with new statistical tools even after many years.
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Affiliation(s)
- Hans-Peter Lipp
- Faculty of Medicine, Institute of Evolutionary Medicine, University of Zürich, Zürich, Switzerland
| | - Sven Krackow
- Institute of Pathology and Molecular Pathology, University Hospital Zürich, Zürich, Switzerland
| | - Emir Turkes
- Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Seico Benner
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Ibaraki, Japan
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Faraji J, Metz GAS. Infrared Thermography Reveals Sex-Specific Responses to Stress in Mice. Front Behav Neurosci 2020; 14:79. [PMID: 32523518 PMCID: PMC7261839 DOI: 10.3389/fnbeh.2020.00079] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 04/28/2020] [Indexed: 01/20/2023] Open
Abstract
Psychogenic hyperthermia is a stress-related condition reported mostly in women. Neuroendocrine responses to stress in females differ from those in males, and these differences cannot be explained solely based on hypothalamic-pituitary-adrenal (HPA) axis activity. Here, we used infrared (IR) thermographic imaging to record changes in cutaneous temperature following two types of stressful experiences in female and male mice. Mice were exposed to either single-session restraint stress or vertical exploration (rearing) deprivation and were monitored for exploratory activity and IR surface thermal changes. Females displayed higher rearing activity than males during the dark phase of the light cycle. Both sexes showed similar plasma corticosterone (CORT) responses after a challenge with restraint and rearing deprivation. However, only females responded to rearing deprivation with increased cutaneous temperature in the head and back, and a reduced thermal response in the tail. Circulating CORT levels were not correlated with the thermal variations. These findings, for the first time, provide evidence for sex-specific cutaneous thermal responses to short-term stress in mice following transient vertical-activity deprivation that may mimic clinical psychogenic hyperthermia.
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Affiliation(s)
- Jamshid Faraji
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.,Faculty of Nursing & Midwifery, Golestan University of Medical Sciences, Gorgan, Iran
| | - Gerlinde A S Metz
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
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3
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Environmental experiences influence cortical volume in territorial and nonterritorial side-blotched lizards, Uta stansburiana. Anim Behav 2016. [DOI: 10.1016/j.anbehav.2016.01.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Faraji J, Soltanpour N, Moeeini R, Hosseini SA, Pakdel S, Moharrerie A, Arjang K, Soltanpour N, Metz GA. Regional vulnerability of the hippocampus to repeated motor activity deprivation. Behav Brain Res 2016; 301:178-89. [DOI: 10.1016/j.bbr.2015.12.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 11/11/2015] [Accepted: 12/18/2015] [Indexed: 12/12/2022]
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5
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Croston R, Branch C, Kozlovsky D, Dukas R, Pravosudov V. Heritability and the evolution of cognitive traits: Table 1. Behav Ecol 2015. [DOI: 10.1093/beheco/arv088] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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6
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Genetic variability, individuality and the evolution of the mammalian brain. Behav Processes 2014; 35:19-33. [PMID: 24896017 DOI: 10.1016/0376-6357(95)00037-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/1995] [Indexed: 12/14/2022]
Abstract
The neo-Darwinian theory of evolution has difficulty in explaining the rapid evolution of mammalian brain and behavior. I shall argue that the plasticity mechanisms of the brain (i.e., system homeostasis, developmental reorganization, structural adult plasticity, and cognition and learning) have evolved primarily as genetic buffer systems which protect subtle mutations influencing brain structures from natural selection. These buffer systems permit accumulation of genetic variation in the higher system levels of the brain (simply defined as structures with late differentiation), while low-level systems are kept constant by natural selection. The organization of this intrinsic genetic buffering system provides several features facilitating neo-Darwinian evolution: In conclusion, the evolutionary appearance of cognition and intelligence is an ordinary biological mechanism compensating evolutionary drags such as long lifespans and fewer offspring. The concept has heuristic value for identifying gene-brain-behavior relationships and for explaining behavioral consequences of artifical gene deletions.
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Alves R, Carvalho JGBD, Venditti MAC. High- and Low-Rearing Rats Differ in the Brain Excitability Controlled by the Allosteric Benzodiazepine Site in the GABA<sub>A</sub> Receptor. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/jbbs.2012.23036] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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8
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Calandreau L, Márquez C, Bisaz R, Fantin M, Sandi C. Differential impact of polysialyltransferase ST8SiaII and ST8SiaIV knockout on social interaction and aggression. GENES BRAIN AND BEHAVIOR 2011; 9:958-67. [PMID: 20659171 DOI: 10.1111/j.1601-183x.2010.00635.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Previous studies using neuronal cell adhesion molecule (NCAM) -/- knockout (KO) mice provided evidence for a role of NCAMs in social behaviors. However, polysialic acid (PSA), the most important post-translational modification of NCAM, was also absent in these mice, which makes it difficult to distinguish between the specific involvement of either PSA or NCAM in social interactions. To address this issue, we assessed two lines of mice deficient for one of the two sialyltransferase enzymes required for the polysialylation of NCAM, sialyltransferase-X (St8SiaII or STX) and polysialyltransferase (ST8SiaIV or PST), in a series of tests for social behaviors. Results showed that PST KO mice display a decreased motivation in social interaction. This deficit can be partly explained by olfactory deficits and was associated with a clear decrease in PSA-NCAM expression in all brain regions analyzed (amygdala, septum, bed nucleus of the stria terminalis and frontal cortices). STX KO mice displayed both a decreased social motivation and an increased aggressive behavior that cannot be explained by olfactory deficits. This finding might be related to the reduced anxiety-like behavior, increased locomotion and stress-induced corticosterone secretion observed in these mice. Moreover, STX KO mice showed mild increase of PSA-NCAM expression in the lateral septum and the orbitofrontal cortex. Altogether, these findings support a role for PSA-NCAM in the regulation of social behaviors ranging from a lack of social motivation to aggression. They also underscore STX KO mice as an interesting animal model that combines a behavioral profile of violence and hyperactivity with reduced anxiety-like behavior.
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Affiliation(s)
- L Calandreau
- Laboratory of Behavioral Genetics, Brain Mind Institute, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland.
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Balemans MC, Huibers MM, Eikelenboom NW, Kuipers AJ, van Summeren RC, Pijpers MM, Tachibana M, Shinkai Y, van Bokhoven H, Van der Zee CE. Reduced exploration, increased anxiety, and altered social behavior: Autistic-like features of euchromatin histone methyltransferase 1 heterozygous knockout mice. Behav Brain Res 2010; 208:47-55. [DOI: 10.1016/j.bbr.2009.11.008] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 10/27/2009] [Accepted: 11/01/2009] [Indexed: 11/16/2022]
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10
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Kobayashi K. Hippocampal Mossy Fiber Synaptic Transmission and Its Modulation. VITAMINS AND HORMONES 2010; 82:65-85. [DOI: 10.1016/s0083-6729(10)82004-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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11
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Kobayashi K, Ikeda Y, Suzuki H. Locomotor activity correlates with modifications of hippocampal mossy fibre synaptic transmission. Eur J Neurosci 2006; 24:1867-73. [PMID: 17040477 DOI: 10.1111/j.1460-9568.2006.05079.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The hippocampus has long been implicated in memory formation. Although accumulating evidence suggests involvement of the hippocampus in other brain functions including locomotor regulation and emotional processes, cellular and synaptic bases underlying these functions remain largely unknown. We here report that environmental manipulations in mice unveiled the association of locomotor activity with the hippocampal mossy fibre (MF) synaptic transmission. Electrophysiological recordings of synaptic responses were made using hippocampal slices prepared from mice whose behaviour had been analysed. Environmental enrichment induced parallel decreases in open-field locomotor activity and MF synaptic facilitation. Facilitation induced by paired-pulse stimulation at relatively long intervals (>or=200 ms) was selectively reduced while the basal synaptic efficacy and high-frequency transmission were unaffected. Social isolation caused a change in behaviour in an elevated plus-maze, but neither the open-field activity nor the MF synaptic transmission was significantly altered. Effects of dopamine, a neurotransmitter essential for locomotor regulation, on the MF synapse were also examined using these mice. Environmental manipulations did not cause significant changes in potentiation of the MF synaptic transmission induced by dopamine. However, analysis of behavioural and electrophysiological results in individual subjects revealed that locomotor activity negatively correlates with magnitude of the dopamine-induced potentiation. These results suggest that the MF synapse plays important roles in the regulation of locomotor activity. We propose that the MF synapse can serve as the synaptic model for certain forms of locomotor regulation, with potential importance for investigation of the pathophysiology of psychiatric diseases using animal models.
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Affiliation(s)
- Katsunori Kobayashi
- Department of Pharmacology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan.
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12
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Pennanen L, Wolfer DP, Nitsch RM, Götz J. Impaired spatial reference memory and increased exploratory behavior in P301L tau transgenic mice. GENES BRAIN AND BEHAVIOR 2006; 5:369-79. [PMID: 16879631 DOI: 10.1111/j.1601-183x.2005.00165.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The neuropathological hallmark shared between Alzheimer's disease (AD) and familial frontotemporal dementia (FTDP-17) are neurofibrillary tangles (NFT) which are composed of filamentous aggregates of the microtubule-associated protein tau. Their formation has been reproduced in transgenic mice, which express the FTDP-17-associated mutation P301L of tau. In these mice, tau aggregates are found in many brain areas including the hippocampus and the amygdala, both of which are characterized by NFT formation in AD. Previous studies using an amygdala-specific test battery revealed an increase in exploratory behavior and an accelerated extinction of conditioned taste aversion in these mice. Here, we assessed P301L mice in behavioral tests known to depend on an intact hippocampus. Morris water maze and Y-maze revealed intact spatial working memory but impairment in spatial reference memory at 6 and 11 months of age. In addition, a modest disinhibition of exploratory behavior at 6 months of age was confirmed in the open field and the elevated O-maze and was more pronounced during aging.
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Affiliation(s)
- L Pennanen
- Division of Psychiatry Research, University of Zurich, Zurich, Switzerland
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Abstract
Many mammals spontaneously rear on their hind legs in response to novelty. The current paper is the first review of rearing behaviour, and is intended to collate findings from different perspectives that are not usually brought together. We suggest that rearing is a useful marker of environmental novelty, that the hippocampal formation is a crucial component of the system controlling rearing in novel environments, and that rearing is one of several ethological measures that can profitably be used to assess hippocampal learning and memory. Consideration is given to the following topics: the possible functions of rearing in information-gathering and escape behaviour; the modulation of rearing by various factors such as anxiety/ fear emotionality; comparative perspectives on rearing; neuroanatomical circuits involved in rearing with particular reference to the hippocampal formation and its afferents and efferents; and the role of the hippocampal formation in uncharted and mismatch environmental novelty. The review concludes with testable predictions about rearing, environmental novelty and the hippocampus.
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Affiliation(s)
- Colin Lever
- Department ofAnatomy and Developmental Biology, University College London, London, UK.
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14
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Alves R, Barbosa de Carvalho JG, Benedito MAC. High and low rearing subgroups of rats selected in the open field differ in the activity of K+-stimulated p-nitrophenylphosphatase in the hippocampus. Brain Res 2005; 1058:178-82. [PMID: 16153614 DOI: 10.1016/j.brainres.2005.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Revised: 08/01/2005] [Accepted: 08/05/2005] [Indexed: 11/19/2022]
Abstract
Na(+)/K(+)-adenosinetriphosphatase (Na(+)/K(+)-ATPase) is of paramount importance for the proper functioning of the organism. The enzyme is involved in several aspects of brain function, such as the repolarization of the neuronal membranes and neurotransmitters uptake/release. Therefore, individual differences in the activity of brain Na(+)/K(+)-ATPase may result in differences in the functioning of the brain, which, in consequence, could lead to behavioral divergences. Individual differences in rearing, an exploratory behavior, have been shown to be genetically determined. In rats, the inhibition of the activity of Na(+)/K(+)-ATPase was reported to induce changes in the exploratory behavior. The aim of this work was to verify if subgroups of rats selected according to the number of rearings (high and low rearing subgroups) in the open field test differ in the activity of Na(+)/K(+)-ATPase in brain regions. Adult, male outbred Wistar rats were selected in the open field test according to the number of rearings in subgroups of high (HR) and low (LR) rearing responders. After a rest of about 20 days after the open field session, HR and LR rats were sacrificed. In the first experiment, frontal cortex, striatum, brainstem, hippocampus and the amygdala (including the overlying limbic cortex) were dissected. The reaction of dephosphorylation of Na(+)/K(+)-ATPase (K(+) stimulated p-nitrophenylphosphatase) was assayed in homogenates rich in synaptosomes. The results obtained showed a statistically significant higher activity of K(+)p-nitrophenylphosphatase only in the hippocampus of HR subgroup of rats. This result was replicated in two other subsequent experiments with different HR and LR subgroups of rats selected at different times of the year. Our data suggest that the difference in the activity of Na(+)/K(+)-ATPase in the hippocampus is innate and is involved in the expression of the rearing behavior.
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Affiliation(s)
- Rosana Alves
- Departamento de Psicobiologia, Universidade Federal de São Paulo, SP, Brazil
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15
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Affiliation(s)
- Reuven Dukas
- Animal Behavior Group, Department of Psychology, McMaster University, Hamilton, Ontario, L8S 4K1, Canada;
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16
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Pan WX, McNaughton N. The supramammillary area: its organization, functions and relationship to the hippocampus. Prog Neurobiol 2004; 74:127-66. [PMID: 15556285 DOI: 10.1016/j.pneurobio.2004.09.003] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2004] [Accepted: 09/15/2004] [Indexed: 11/18/2022]
Abstract
The supramammillary area of the hypothalamus, although small in size, can have profound modulatory effects on the hippocampal formation and related temporal cortex. It can control hippocampal plasticity and also has recently been shown to contain cells that determine the frequency of hippocampal rhythmical slow activity (theta rhythm). We review here its organization and anatomical connections providing an atlas and a new nomenclature. We then review its functions particularly in relation to its links with the hippocampus. Much of its control of behaviour and its differential activation by specific classes of stimuli is consistent with a tight relationship with the hippocampus. However, its ascending connections involve not only caudal areas of the cortex with close links to the hippocampus but also reciprocal connections with more rostral areas such as the infralimbic and anterior cingulate cortices. These latter areas appear to be the most rostral part of a network that, via the medial septum, hippocampus and lateral septum, is topographically mapped into the hypothalamus. The supramammillary area is thus diffusely connected with areas that control emotion and cognition and receives more topographically specific return information from areas that control cognition while also receiving ascending information from brain stem areas involved in emotion. We suggest that it is a key part of a network that recursively transforms information to achieve integration of cognitive and emotional aspects of goal-directed behaviour.
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Affiliation(s)
- Wei-Xing Pan
- Department of Physiology and Center for Neuroscience, University of Otago, POB56, Dunedin, New Zealand
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17
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Prior H, Schwegler H, Marashi V, Sachser N. Exploration, emotionality, and hippocampal mossy fibers in nonaggressive AB/Gat and congenic highly aggressive mice. Hippocampus 2004; 14:135-40. [PMID: 15058491 DOI: 10.1002/hipo.10166] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
AB/Gat mice and congenic mice bred for high aggressiveness (CS/ag) were tested for exploratory behavior in novel situations and anxiety-related behavior, using an open-field test and the elevated plus-maze test. Subsequently, the size of hippocampal mossy fiber terminal fields was evaluated. Considerably higher exploratory activity was found in nonaggressive mice, whereas aggressive mice exhibited more anxiety-related behavior. Larger intra- and infrapyramidal mossy fiber terminal fields (IIP-MF) and a larger hilus were found in the highly aggressive strain. Within the nonaggressive AB/Gat strain, larger IIP-MF were correlated with higher exploratory behavior and lower anxiety in the plus-maze test. Within the aggressive strain, no individual correlations between hippocampal morphometry and behavior were found. The results corroborate the "ecotype hypothesis," which suggests that mice of subpopulations with highly aggressive males tend to display reduced exploratory behavior. The findings support the view that genetic factors involved in aggressive behavior also affect hippocampal connectivity. However, our results do not support the hypothesis that a higher level of aggressiveness is necessarily related to smaller IIP-MF.
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Affiliation(s)
- Helmut Prior
- AE Biopsychologie, Ruhr-Universität Bochum, Bochum, Germany.
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Huot RL, Plotsky PM, Lenox RH, McNamara RK. Neonatal maternal separation reduces hippocampal mossy fiber density in adult Long Evans rats. Brain Res 2002; 950:52-63. [PMID: 12231228 DOI: 10.1016/s0006-8993(02)02985-2] [Citation(s) in RCA: 308] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Neonatal maternal separation of rat pups leads to a stable stress hyper-responsive phenotype characterized by increased basal levels of corticotropin releasing factor (CRF) mRNA in the hypothalamic and extra-hypothalamic nuclei, increased hypothalamic CRF release, and enhanced adrenocorticotrophin hormone (ACTH) and corticosterone (CORT) responses to psychological stressors. Stress and exposure to glucocorticoids either early in life or in adulthood have been associated with hippocampal atrophy and impairments in learning and memory. In this study, male Long Evans rat pups were exposed to daily 3-h (HMS180) or 15-min (HMS15) periods of maternal separation on postnatal days (PND) 2-14 or normal animal facility rearing. Maternal separation and subsequent reunion with the dam resulted in elevated plasma CORT levels versus HMS15 animals at PND7, a time when rat pups are normally hyporesponsive to stressors and show limited pituitary-adrenal responses. As adults, HMS180 rats exhibited elevated indices of anxiety, startle-induced pituitary-adrenal hyper-responsiveness, and slight, but significant impairment on acquisition in the Morris water maze task. In addition, HMS180 rats exhibited decreased mossy fiber density in the stratum oriens region of the hippocampus as measured by Timm's staining, but no change in volume of the dentate gyrus. These changes may be the result of neonatal exposure to elevated glucocorticoids and/or changes in other signaling systems in response to maternal separation. Overall the results suggest that repeated, daily, 3-h maternal separations during critical periods of hippocampal development can disrupt hippocampal cytoarchitecture in a stable manner. The resulting change in morphology may contribute to the subtle, but consistent learning deficit and overall stress hyper-responsive phenotype observed in these animals.
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Affiliation(s)
- Rebecca L Huot
- Stress Neurobiology Laboratory, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, 1639 Pierce Drive, Atlanta, GA 30322, USA
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Eshel G, Reisler G, Berkovitch M, Shapira S, Grauer E, Barr J. Comparison of fast versus slow rewarming following acute moderate hypothermia in rats. Paediatr Anaesth 2002; 12:235-42. [PMID: 11903937 DOI: 10.1046/j.1460-9592.2002.00801.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The aim of this study was to compare the biochemical and physiological responses of fast vs. slow rewarming from moderate hypothermia in anaesthetized rats. METHODS Anaesthetized rats were surface cooled to 28 degrees C, for 20 min, then rewarmed either quickly over 30 min or slowly over 120 min with monitoring of vital signs, systemic vascular resistance (SVR), cardiac output, biochemical changes and activity for 31 days. RESULTS At hypothermia, cardiac output decreased to 77 +/- 38 ml x min(-1) and lactate increased to 4.62 +/- 4.73 mmol x l(-)1. Fast rewarming caused an abrupt increase in cardiac output (270 +/- 24 ml x min(-1)) and a sharp drop in SVR (325.6 +/- 23.3 dyne x s(-1) x cm(-5)), compared with a smoother course with cardiac output (142 +/- 18 ml x min(-1), P < 0.01) and SVR (662.8 +/- 41.0 dyne x s(-1) x cm(-5), P < 0.01), measured during slow rewarming. Lactate failed to return to normal values (upon returning to normothermia) (2.5 +/- 0.75 mmol x l(-1)) only in the fast rewarming group. In both groups, activity in the open field was not different from control rats. CONCLUSIONS In rats, moderate hypothermia for 20 min does not appear to cause lasting biochemical or behavioural consequences, whether rewarming lasted over 30 or 120 min. However, there was a greater early change in cardiac output and heart rate, due to systemic vasodilatation in the fast rewarming animals. These acute changes may have consequences in patients with compromised cardiovascular reserves.
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Affiliation(s)
- Gideon Eshel
- Pediatric Intensive Care Unit, Assaf Harofeh Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Zerifin, Israel
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Lassalle JM, Bataille T, Halley H. Reversible inactivation of the hippocampal mossy fiber synapses in mice impairs spatial learning, but neither consolidation nor memory retrieval, in the Morris navigation task. Neurobiol Learn Mem 2000; 73:243-57. [PMID: 10775494 DOI: 10.1006/nlme.1999.3931] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The role played by hippocampal mossy fibers in the learning and memory processes implemented in the Morris swimming navigation task has been studied in C57BL/6 mice by selective and reversible inactivation of mossy fiber synaptic fields by diethyldithiocarbamate. The functional integrity of the mossy fibers proved essential for the storage of the spatial representation on the modifiable synapses of the recurrent collaterals of the CA3 pyramidal cells, whereas it is not necessary for the consolidation and recall of spatial memories. The results suggest that mossy fibers are preferentially involved in new learning. They are consistent with the hypothesis that the hippocampal CA3 region might act as an autoassociation memory.
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Affiliation(s)
- J M Lassalle
- Laboratoire d'Ethologie et Psychologie Animale, Université Paul Sabatier, Toulouse, UMR 5550 CNRS, France.
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Pleskacheva MG, Wolfer DP, Kupriyanova IF, Nikolenko DL, Scheffrahn H, Dell'Omo G, Lipp HP. Hippocampal mossy fibers and swimming navigation learning in two vole species occupying different habitats. Hippocampus 2000; 10:17-30. [PMID: 10706213 DOI: 10.1002/(sici)1098-1063(2000)10:1<17::aid-hipo2>3.0.co;2-o] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We showed previously for mice that size differences of the infrapyramidal hippocampal mossy fiber projection (IIP-MF) correlate with spatial learning abilities. In order to clarify the role of the IIP-MF in a natural environment, we studied the bank vole (Clethrionomys glareolus), adapted to a wide range of different habitats, and the root vole (Microtus oeconomus), living in homogenous grassland habitats with small home ranges. Morphometry on Timm-stained horizontal brain sections of six C. glareolus and six M. oeconomus revealed that the size of the entire mossy fiber projection was 42% larger in C. glareolus than M. oeconomus. C. glareolus had also an IIP-MF projection about 230% larger than that of the root vole. A sample of captured animals was then transferred to the laboratory (C. glareolus, n = 23; M. oeconomus, n = 15) and underwent testing for swimming navigation according to a standardized protocol used to assess water maze learning in about 2,000 normal and transgenic mice. Both species learned faster than laboratory mice. Overall escape times showed no differences, but path length was significantly reduced in C. glareolus, which also showed superior performance in a variety of scores assessing spatial search patterns. On the other hand, M. oeconomus showed faster swimming speed, and strong thigmotaxis combined with circular swimming. M. oeconomus also scored at chance levels during the probe trial, about as poorly as mutant knockout mice considered to be deficient in spatial memory. These differences probably reflect differential styles of water maze learning rather than spatial memory deficits: C. glareolus appears to be superior in inhibiting behavior interfering with proper spatial search behavior, while M. oeconomus succeeds in escaping by using rapid circular swimming. We assume that size variations of the IIP-MF correspond to a mechanism stabilizing hippocampal processing during spatial learning or complex activities. This corresponds to the ecological lifestyle of the two species and is in line with previous observations on the role of the IIP-MF.
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Affiliation(s)
- M G Pleskacheva
- Laboratory of Physiology and Genetics of Behavior, Faculty of Biology, Moscow State University, Russia
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Prior H, Schwegler H, Dücker G. Dissociation of spatial reference memory, spatial working memory, and hippocampal mossy fiber distribution in two rat strains differing in emotionality. Behav Brain Res 1997; 87:183-94. [PMID: 9331486 DOI: 10.1016/s0166-4328(97)02282-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Rats of the inbred strains DA/Han and BDE/Han were compared on two complex spatial learning tasks, a spatial reference memory task in a 16-unit multiple T-maze and a spatial working memory task in an eight-arm radial-maze. In addition, sizes of hippocampal mossy fiber terminal fields were measured. BDE rats showed marked superiority in multiple T-maze learning whereas DA rats outperformed BDE rats on the radial-maze task. DA rats had significantly larger intra- and infrapyramidal mossy fiber terminal fields (IIP-MF). This is consistent with findings from other studies suggesting that large IIP-MF are related to excellent spatial radial-maze learning, but it also indicates that size of IIP-MF is correlated with processing of a specific type of spatial information rather than with overall spatial abilities. BDE rats had more extended suprapyramidal mossy fiber projections (SP-MF) and a larger hilus. Rats of both strains differed in exploratory behaviour and emotionality: DA rats revealed little freezing and had a high rearing activity, whereas BDE rats showed frequent freezing and reared rarely. Results suggest that IIP-MF are involved with flexible expression of memory, updating environmental information and parallel processing whereas SP-MF might be linked to processing of familiar information. Presumably, emotional factors contribute to performance differences.
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Affiliation(s)
- H Prior
- Universität Münster, Institut für Neuro- und Verhaltensbiologie, Germany.
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Lipp HP, Collins RL, Hausheer-Zarmakupi Z, Leisinger-Trigona MC, Crusio WE, Nosten-Bertrand M, Signore P, Schwegler H, Wolfer DP. Paw preference and intra-/infrapyramidal mossy fibers in the hippocampus of the mouse. Behav Genet 1996; 26:379-90. [PMID: 8771898 DOI: 10.1007/bf02359482] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The size of the intra-/infrapyramidal mossy fiber projections (IIP-MF) and their left/right asymmetry were assessed in 86 mice of either sex, including 26 animals from two mouse lines bred for strong or weak paw preference, 38 mice of a randomly bred F3 generation derived from an eight-way cross, and 22 mice with variably sized corpora callosa in which only the left hippocampus was measured. Prior to morphometry, all mice were tested for paw preference. In addition, we compared the strain means in paw preference as observed in nine inbred mouse strains with known differences in their IIP-MF distribution. Mice bred for strong paw preference had a 70% larger IIP-MF projection than weakly lateralized and dyscallosal mice; random-bred mice fell in-between the extremes. The individual scores of the strength of paw preference were positively correlated with the extent of the IIP-MF. Among the inbred strains, the extent of the IIP-MF was similarly correlated with the strength of paw preference. The acallosal mice showed a significant negative correlation between extent of the IIP-MF projection and test-retest reliability of paw use. The left-right asymmetry of the IIP-MF was significantly and positively correlated with the direction of paw preference in the entire sample. We conclude that size and asymmetry of the IIP-MF projection are some of the many factors influencing the direction of paw preference and its strength, albeit moderately. We hypothesize that mice with larger IIP-MF projections use a given paw more consistently, being perhaps more resistant to interferences, and that left-right asymmetries of the IIP-MF may bias and/or reinforce an initial choice of a paw. In addition, the data provide another example of correlations between IIP-MF variations and nonspatial behavior.
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Affiliation(s)
- H P Lipp
- Institute of Anatomy, University of Zürich-Irchel, Switzerland.
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