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Anja Guenther - One of the best experts on this subject based on the ideXlab platform.
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life history trade offs are they linked to personality in a precocial mammal cavia aperea
Biology Letters, 2018Co-Authors: Anja GuentherAbstract:Life-history trade-offs are predicted to contribute to the maintenance of personality variation. Individuals with ‘fast’ lifestyles should develop faster, reproduce earlier and exhibit more risky behaviours. Evidence for such predicted links, however, remains equivocal. Here, I test how growth rate, timing of maturation, litter size and maternal effort correlate with exploration, boldness, fearlessness, docility and Escape Latency. I found several links that were predicted by recent theory while others were against theoretical predictions, e.g. fast-growing individuals were more fearful. Thus, while I found personality to be integrated with life history, I cannot fully support recent hypotheses aiming to explain such behaviour–life-history associations.
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raw data supporting manuscript "Life history trade-offs: are they linked to personality in a precocial mammal"
2018Co-Authors: Anja GuentherAbstract:These are raw data for life history traits (growth, maturation, litter size, reproductive effort) and behaviours (exploration, boldness, Escape Latency and docility) repeatedly measured in 100 female Cavia aperea. The animals were held in captivity, either under indoor or combined indoor-outdoor housing. All animals experienced natural photoperiods, animals in combined indoor-outdoor housing experienced natural temperatures in addition. For description of variables, see "read.me"
James L Meyerhoff - One of the best experts on this subject based on the ideXlab platform.
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activity wheel running reduces Escape Latency and alters brain monoamine levels after footshock
Brain Research Bulletin, 1997Co-Authors: Rod K Dishman, Kenneth J Renner, Shawn D Youngstedt, Thomas G Reigle, B N Bunnell, K A Burke, Edward H Mougey, James L MeyerhoffAbstract:Abstract We examined the effects of chronic activity wheel running on brain monoamines and Latency to Escape foot shock after prior exposure to uncontrollable, inescapable foot shock. Individually housed young (∼50 day) female Sprague-Dawley rats were randomly assigned to standard cages (sedentary) or cages with activity wheels. After 9–12 weeks, animals were matched in pairs on body mass. Activity wheel animals were also matched on running distance. An animal from each matched pair was randomly assigned to controllable or uncontrollable inescapable foot shock followed the next day by a foot shock Escape test in a shuttle box. Brain concentrations of norepinephrine (NE), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), 5-hydroxytryptamine (5-HT), and 5-hydroxyindole acetic acid (5-HIAA) were assayed in the locus coeruleus (LC), dorsal raphe (DR), central amygdala (AC), hippocampus (CA1), arcuate nucleus, paraventricular nucleus (PVN), and midbrain central gray. After prior exposure to uncontrollable foot shock, Escape Latency was reduced by 34% for wheel runners compared with sedentary controls. The shortened Escape Latency for wheel runners was associated with 61% higher NE concentrations in LC and 44% higher NE concentrations in DR compared with sedentary controls. Sedentary controls, compared with wheel runners, had 31% higher 5-HIAA concentrations in CA1 and 30% higher 5-HIAA concentrations in AC after uncontrollable foot shock and had 28% higher 5-HT and 33% higher 5-HIAA concentrations in AC averaged across both foot shock conditions. There were no group differences in monoamines in the central gray or in plasma prolactin or ACTH concentrations, despite 52% higher DA concentrations in the arcuate nucleus after uncontrollable foot shock and 50% higher DOPAC/DA and 17% higher 5-HIAA/5-HT concentrations in the PVN averaged across both foot shock conditions for sedentary compared with activity wheel animals. The present results extend understanding of the Escape-deficit by indicating an attenuating role for circadian physical activity. The altered monoamine levels suggest brain regions for more direct probes of neural activity after wheel running and foot shock.
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activity wheel running reduces Escape Latency and alters brain monoamine levels after footshock
Brain Research Bulletin, 1997Co-Authors: Rod K Dishman, Kenneth J Renner, Shawn D Youngstedt, Thomas G Reigle, B N Bunnell, K A Burke, Edward H Mougey, H S Yoo, James L MeyerhoffAbstract:We examined the effects of chronic activity wheel running on brain monoamines and Latency to Escape foot shock after prior exposure to uncontrollable, inescapable foot shock. Individually housed young (approximately 50 day) female Sprague-Dawley rats were randomly assigned to standard cages (sedentary) or cages with activity wheels. After 9-12 weeks, animals were matched in pairs on body mass. Activity wheel animals were also matched on running distance. An animal from each matched pair was randomly assigned to controllable or uncontrollable inescapable foot shock followed the next day by a foot shock Escape test in a shuttle box. Brain concentrations of norepinephrine (NE), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), 5-hydroxytryptamine (5-HT), and 5-hydroxyindole acetic acid (5-HIAA) were assayed in the locus coeruleus (LC), dorsal raphe (DR), central amygdala (AC), hippocampus (CA1), arcuate nucleus, paraventricular nucleus (PVN), and midbrain central gray. After prior exposure to uncontrollable foot shock, Escape Latency was reduced by 34% for wheel runners compared with sedentary controls. The shortened Escape Latency for wheel runners was associated with 61% higher NE concentrations in LC and 44% higher NE concentrations in DR compared with sedentary controls. Sedentary controls, compared with wheel runners, had 31% higher 5-HIAA concentrations in CA1 and 30% higher 5-HIAA concentrations in AC after uncontrollable foot shock and had 28% higher 5-HT and 33% higher 5-HIAA concentrations in AC averaged across both foot shock conditions. There were no group differences in monoamines in the central gray or in plasma prolactin or ACTH concentrations, despite 52% higher DA concentrations in the arcuate nucleus after uncontrollable foot shock and 50% higher DOPAC/DA and 17% higher 5-HIAA/5-HT concentrations in the PVN averaged across both foot shock conditions for sedentary compared with activity wheel animals. The present results extend understanding of the Escape-deficit by indicating an attenuating role for circadian physical activity. The altered monoamine levels suggest brain regions for more direct probes of neural activity after wheel running and foot shock.
Paolo Domenici - One of the best experts on this subject based on the ideXlab platform.
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Latency of mechanically stimulated Escape responses in the pacific spiny dogfish squalus suckleyi
The Journal of Experimental Biology, 2021Co-Authors: Mathias Schakmann, Victoria Becker, Mathias Sogaard, Jacob L Johansen, John F Steffensen, Paolo DomeniciAbstract:ABSTRACT Fast Escape responses to a predator threat are fundamental to the survival of mobile marine organisms. However, elasmobranchs are often underrepresented in such studies. Here, we measured the Escape Latency (time interval between the stimulus and first visible reaction) of mechanically induced Escape responses in the Pacific spiny dogfish, Squalus suckleyi, and in two teleosts from the same region, the great sculpin, Myoxocephalus polyacanthocephalus, and the pile perch, Rhacochilus vacca. We found that the dogfish had a longer minimum Latency (66.7 ms) compared with that for the great sculpin (20.8 ms) and pile perch (16.7 ms). Furthermore, the dogfish had a longer Latency than that of 48 different teleosts identified from 35 different studies. We suggest such long latencies in dogfish may be due to the absence of Mauthner cells, the giant neurons that control fast Escape responses in fishes.
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context dependent variability in the components of fish Escape response integrating locomotor performance and behavior
Journal of Experimental Zoology, 2010Co-Authors: Paolo DomeniciAbstract:Escape responses are used by most fish species in order to avoid predation. Escape responses include a number of behavioral and kinematic components, such as responsiveness, reaction distance, Escape Latency, directionality, and distance-derived performance. All of these components can contribute to Escape success. Work on the context-dependent variability has focused on reaction distance, and suggests that this component is largely determined by the relative cost and benefits of escaping (economic hypothesis). For example, reaction distance was found to depend on many factors related to perceived risk and cost of escaping, such as the attack speed and size of the predators, the proximity to refuges, and engagement in other activities (e.g., feeding). Evidence from many behavioral, kinematic, and physiological studies suggest that performance in other components of the Escape response is also not always maximized. For example, Escape latencies may increase in the presence of schooling neighbors, and Escape speed is higher in fish that have been subject to higher predation pressure. In addition, all Escape components are further modulated by the effect of environmental factors. Variability in Escape components can be interpreted by using both ultimate and proximate explanations, for example, the effect of stimulus strength on Escape Latency can be interpreted as the triggering neural threshold varying with stimulus strength (proximate explanation) and high intensity stimuli representing higher risk to the prey (ultimate explanation). An integrative approach is suggested for a full, ecologically relevant, assessment of Escape performance in fish. J. Exp. Zool. 313A:59–79, 2010. © 2010 Wiley-Liss, Inc.
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context dependent variability in the components of fish Escape response integrating locomotor performance and behavior
Journal of Experimental Zoology, 2010Co-Authors: Paolo DomeniciAbstract:Escape responses are used by most fish species in order to avoid predation. Escape responses include a number of behavioral and kinematic components, such as responsiveness, reaction distance, Escape Latency, directionality, and distance-derived performance. All of these components can contribute to Escape success. Work on the context-dependent variability has focused on reaction distance, and suggests that this component is largely determined by the relative cost and benefits of escaping (economic hypothesis). For example, reaction distance was found to depend on many factors related to perceived risk and cost of escaping, such as the attack speed and size of the predators, the proximity to refuges, and engagement in other activities (e.g., feeding). Evidence from many behavioral, kinematic, and physiological studies suggest that performance in other components of the Escape response is also not always maximized. For example, Escape latencies may increase in the presence of schooling neighbors, and Escape speed is higher in fish that have been subject to higher predation pressure. In addition, all Escape components are further modulated by the effect of environmental factors. Variability in Escape components can be interpreted by using both ultimate and proximate explanations, for example, the effect of stimulus strength on Escape Latency can be interpreted as the triggering neural threshold varying with stimulus strength (proximate explanation) and high intensity stimuli representing higher risk to the prey (ultimate explanation). An integrative approach is suggested for a full, ecologically relevant, assessment of Escape performance in fish.
Byung Hoon Yoon - One of the best experts on this subject based on the ideXlab platform.
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the seed extract of cassia obtusifolia ameliorates learning and memory impairments induced by scopolamine or transient cerebral hypoperfusion in mice
Journal of Pharmacological Sciences, 2007Co-Authors: Byung Hoon Yoon, Ji Wook Jung, Bum Young Shin, Jae Sue ChoiAbstract:In the present study, we assessed the effect of the ethanolic extract of the seeds of Cassia obtusifolia (COE) on the learning and memory impairments induced by scopolamine or transient bilateral common carotid artery occlusion (2VO). In a study of the cholinergic dysfunction induced by scopolamine, single COE (25, 50, or 100 mg/kg, p.o.) administration significantly attenuated scopolamine-induced cognitive impairments as determined by the passive avoidance and Y-maze tasks (P<0.05) and also reduced Escape-Latency on the Morris water maze task (P<0.05). In the 2VO study, COE (50 mg/kg, p.o.) significantly reversed 2VO-induced cognitive impairments in mice by the passive avoidance and the Y-maze tasks (P<0.05). Moreover, COE (50 mg/kg, p.o.) also reduced Escape-Latency and prolonged swimming time in the target quadrant during a probe trial of the Morris water maze task (P<0.05). In an in vitro study, COE was found to inhibit acetylcholinesterase activity in a dose-dependent manner (IC50 value: 81.6 μg/ml). Furthermore, COE also inhibited acetylcholinesterase activity in an ex vivo study. These results suggest that COE attenuates memory impairment induced by scopolamine or 2VO and that these effects are mediated by enhancing the cholinergic nervous system via acetylcholinesterase inhibition.
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gomisin a improves scopolamine induced memory impairment in mice
European Journal of Pharmacology, 2006Co-Authors: Donghyun Kim, Tran Manh Hung, Kihwan Bae, Ji Wook Jung, Seungjoo Lee, Byung Hoon Yoon, Jae Hoon Cheong, Jong Hoon RyuAbstract:Gomisin A is a component of the fruits of Schizandra chinesis which are widely used as a tonic in traditional Chinese medicine. In the present study, we assessed the effect of gomisin A on the learning and memory impairments induced by scopolamine. The cognition-enhancing effect of gomisin A was investigated using a passive avoidance test, the Y-maze test, and the Morris water maze test in mice. Drug-induced amnesia was induced by treating animals with scopolamine (1 mg/kg, i.p.). Gomisin A (5 mg/kg, p.o.) administration significantly reversed scopolamine-induced cognitive impairments in mice by the passive avoidance test and the Y-maze test (P<0.05), and also improved Escape Latency in the Morris water maze test at 5 mg/kg (P<0.05). Moreover, in an in vitro study, gomisin A was found to inhibit acetylcholinesterase activity in a dose-dependent manner (IC50 value; 15.5 microM). These results suggest that gomisin A may be a useful cognitive impairment treatment, and its beneficial effects are mediated, in part, via enhancing the cholinergic nervous system.
Aihua Wang - One of the best experts on this subject based on the ideXlab platform.
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the calcineurin inhibitor fk506 prevents cognitive impairment by inhibiting reactive astrogliosis in pilocarpine induced status epilepticus rats
Frontiers in Cellular Neuroscience, 2018Co-Authors: Zhihua Si, Tao Zhang, Shuqing Li, Zhan Huang, Yan He, Aihua WangAbstract:Status epilepticus (SE) is a severe clinical manifestation of epilepsy accompanying with cognitive impairment and brain damage. Astrocyte activation occurs following seizures and plays an important role in epilepsy-induced pathological injury, including cognitive impairment. FK506, an immunosuppressant used in clinical settings to prevent allograft rejection, has been shown to exhibit neuroprotective effects in central nervous system diseases. The present study was designed to investigate the effect of FK506 on cognitive impairment in a lithium-pilocarpine-induced SE rat model. It’s found that FK506 treatment significantly increased the Latency period to seizures and decreased the maximal intensity of seizures. FK506 treatment also markedly increased the surviving cells and reduced the neuron apoptosis after seizures. Meanwhile, FK506 treatment reduced the Escape Latency and prolonged the swimming distance in the Morris water maze test. In addition, FK506 treatment down-regulated the expression level of GFAP, a specific marker of astrocytes. In conclusion, FK506 could prevent and recover cognitive impairment by inhibiting reactive astrogliosis in pilocarpine-induced status epilepticus rats, suggesting that FK506 may be a promising agent for the treatment of epilepsy.