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101.
目的: 探索对香豆酸(p-CA)对慢性束缚应激(CRS)诱导小鼠抑郁样行为的作用。方法: 实验分两批进行,第一批小鼠随机分成对照组(Control),慢性束缚应激组(CRS)和慢性束缚应激+p-CA组(CRS+p-CA),每组8只,其中慢性束缚应激小鼠每天接受4 h的束缚应激,连续束缚21 d,而对照组小鼠留在笼中不被打扰。第22日小鼠腹腔注射溶媒(10%吐温80)或p-CA(100 mg/kg),注射后1 h进行自发活动测试(LMA),注射后4 h进行强迫游泳测试(FST),注射后24 h进行悬尾测试。第二批小鼠随机分成慢性束缚应激组(CRS) ,慢性束缚应激+ANA-12(原肌球蛋白激酶B拮抗剂)组(CRS+ANA-12)和慢性束缚应激+p-CA组(CRS+ p-CA)慢性束缚应激+p-CA +ANA-12组(CRS+ p-CA +ANA-12),每组8只,4组小鼠每天接受4 h的束缚应激,连续束缚21 d。第22日小鼠腹腔注射溶媒(10%吐温80)或p-CA(100 mg/kg),ANA-12(0.5 mg/kg)在p-CA注射前30 min给药。注射后1 h进行自发活动测试(LMA),注射后2 h进行强迫游泳测试(FST),注射后24 h进行悬尾测试。结果: ①在实验一中,与Control组相比,CRS组小鼠强迫游泳和悬尾测试中不动时间显著性增多(P<0.05);而与CRS组相比,CRS+ p-CA组小鼠不动时间显著性减少(P<0.05,P<0.01)。②在实验二中,与CRS组相比,CRS+ p-CA组小鼠强迫游泳和悬尾测试中不动时间显著性减少(P<0.05);而与CRS+ p-CA组相比,CRS+ p-CA +ANA-12组小鼠强迫游泳和悬尾测试中不动时间显著性增多(P<0.05)。结论: P-CA改善慢性束缚应激诱导小鼠抑郁样行为,TrkB受体可能介导了此作用。 相似文献
102.
Cintia Organo Quintana Min Tang 《Journal of experimental marine biology and ecology》2007,352(2):392-406
The present study employed simultaneously methods to investigate particle and solute transport and reaction rates in sandy sediments inhabited by two worms (2500 m− 2) with different feeding modes. Heteromastus filiformis is a head-down deposit-feeder and the main activities exerted by this worm are transport of particles as faecal pellets from subsurface to surface sediments and burrow ventilation. Marenzelleria viridis is a surface deposit-feeder that actively searches for food by burrowing near the sediment surface, producing a network of ventilated galleries in this zone. M. viridis exhibited 1.5 to 2.2 times higher particle mixing rates (Db = 3.3 to 4 × 10− 3 cm− 2 d− 1) compared to H. filiformis. In M. viridis treatments, continuous advection (eddy diffusion) was the major factor influencing solute transport resulting in apparent diffusion rates (Da = 2.2 cm− 2 d− 1), which were 3 times higher than molecular diffusion within the sediment. In H. filiformis inhabited sediments, the transport of solutes was discontinuous and driven by a surprisingly high nonlocal exchange (α = 1.1-1.3 d− 1), emphasizing its strong irrigation effects. Accordingly, the enhancement of solute fluxes was more pronounced for H. filiformis compared to M. viridis. Depth integrated TCO2 production derived from diagenetic modelling, which takes into account three reaction zones, is in good agreement with rates obtained from measured fluxes, indicating the applicability of both approaches to get reliable rates. However, the reaction rates showed that the presence of animals had a modest effect on microbial carbon oxidation. The results proved that transport conditions are deeply related to feeding modes. Exchange of solutes was the most important transport process by H. filiformis, while M. viridis affected both mixing and solute transport. 相似文献
103.
The concept of personality implies individual differences in behavior and physiology that show some degree of repeatability/consistency over time and across contexts. Most studies of animal personality, particularly studies of individuals' variation in physiological mechanisms, have been conducted on selected individuals in controlled conditions. We attempted to detect consistent behaviors as well as physiological patterns in greylag ganders (Anser anser) from a free-roaming flock living in semi-natural conditions. We tested 10 individuals repeatedly, in a handling trial, resembling tests for characterization of "temperaments" in captive animals. We recorded the behavior of the same 10 individuals during four situations in the socially intact flock: (1) a "low density feeding condition", (2) a "high density feeding condition", (3) a "low density post-feeding situation" and (4) while the geese rested. We collected fecal samples for determination of excreted immuno-reactive corticosterone (BM) and testosterone metabolites (TM) after handling trials, as well as the "low density feeding" and the "high density feeding" conditions. BM levels were very highly consistent over the repeats of handling trials, and the "low density feeding condition" and tended to be consistent over the first two repeats of the "high density feeding condition". Also, BM responses tended to be consistent across contexts. Despite seasonal variation, there tended to be inter-test consistency of TM, which pointed to some individual differences in TM as well. Aggressiveness turned out to be a highly repeatable trait, which was consistent across social situations, and tended to correlate with an individual's resistance during handling trials. Also, "proximity to the female partner" and "sociability" - the average number of neighboring geese in a close distance while resting - were consistent. We conclude that aggressiveness, "affiliative tendencies" and levels of excreted corticosterone and testosterone metabolites may be crucial factors of personality in geese. 相似文献
104.
Siberian hamsters (Phodopus sungorus) exhibit reproductive and immunological responses to photoperiod. Short (<10-h light/day) days induce gonadal atrophy, increase leukocyte concentrations, and attenuate thermoregulatory and behavioral responses to infection. Whereas hamster reproductive responses to photoperiod are dependent on pineal melatonin secretion, the role of the pineal in short-day induced changes in immune function is not fully understood. To examine this, adult hamsters were pinealectomized (PINx) or sham-PINx, and transferred to short days (9-h light/day; SD) or kept in their natal long-day (15-h light/day; LD) photoperiod. Intact and PINx hamsters housed in LD maintained large testes over the next 12 weeks; sham-PINx hamsters exhibited gonadal regression in SD, and PINx abolished this effect. Among pineal-intact hamsters, blood samples revealed increases in leukocyte, lymphocyte, CD62L+ lymphocyte, and T cell counts in SD relative to LD; PINx did not affect leukocyte numbers in LD hamsters, but abolished the SD increase in these measures. Hamsters were then treated with bacterial lipopolysaccharide (LPS), which induced thermoregulatory (fever), behavioral (anorexia, reductions in nest building), and somatic (weight loss) sickness responses in all groups. Among pineal-intact hamsters, febrile and behavioral responses to LPS were attenuated in SD relative to LD. PINx did not affect sickness responses to LPS in LD hamsters, but abolished the ameliorating effects of SD on behavioral responses to LPS. Surprisingly, PINx failed to abolish the effect of SD on fever. In common with the reproductive system, PINx induces the LD phenotype in most aspects of the immune system. The pineal gland is required for photoperiodic regulation of circulating leukocytes and neural-immune interactions that mediate select aspects of sickness behaviors. 相似文献
105.
Age-related differences in the performance, diffusion, and maintenance of stone handling, a behavioral tradition in Japanese macaques 总被引:1,自引:1,他引:0
Identifying the sources of behavioral diversity in non-human primates is vital to understanding the evolution of human behavior. Stone handling (SH, hereafter) is a form of object play consisting of the manipulation of stones by performing various behavioral patterns. This behavior is socially transmitted from generation to generation in Japanese macaques (Macaca fuscata), as a behavioral tradition. SH behavior in particular may reflect on the origin and evolution of stone-tool material culture. The objective of this study was to assess how group size, age structure, and age- and sex-related differences may account for the substantial intra- and inter-troop variations in SH reported in ten troops of Japanese macaques. Our results supported the hypothesis that patterns of variation in SH across troops reflected variability in group size and composition in age classes. We found that troop size was correlated with the proportion of troop members exhibiting SH simultaneously. The effect of troop size on the synchronized performance of SH may reveal the contagious nature of play. Our results suggest that the age structure of the group may affect the diffusion of SH. As predicted by the surplus energy hypothesis, a major functional hypothesis about play, intra-group variation in SH reflected more age- than sex-related differences. SH mainly occurred and was more frequent in younger than in older individuals, whereas no significant sex differences were found. SH episodes were shorter, more vigorous, and SH patterns were more diverse and less complex in immature than in mature individuals. The present findings reveal that age-related factors and group size may constrain the performance, diffusion, and maintenance of SH within a troop. Contrary to most other socially transmitted stone-tool using behaviors in non-human primates and early hominids, there is no optimal SH pattern. Provided some form of social learning, the non-adaptive nature of SH may allow particular SH pattern preferences to emerge at the group level. Our findings urge the use of an inter-populational comparative approach based on multivariate analyses when addressing the question of the evolution of behavioral traditions in primate and human populations. 相似文献
106.
Aiko Watanabe Hiroko Eda-Fujiwara Takeji Kimura 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(1):81-97
Among avian species that communicate using vocalization, songbirds (oscine Passeriformes), hummingbirds (Trochiliformes),
and parrots (Psittaciformes) are vocal learners. Early studies showed that songbirds require auditory feedback for song development
in young and maintenance in adults. To determine whether auditory feedback is also necessary for adult song maintenance in
non-passerine species, we deprived adult male budgerigars (Psittaciformes) of auditory input by surgical cochlear removal.
Songs of the deafened birds changed within 6 months after auditory deprivation. In postoperative songs, high narrowband syllables,
which comprised frequency-modulated narrowband elements with relatively high fundamental frequencies of 2–4 kHz, decreased
significantly. High harmonic broadband syllables, with fundamental frequencies ≥2 kHz, also decreased. The altered proportions
of syllables were subsequently retained, and maintained 12 months after deafening. The sequence linearity score, a parameter
representing the stereotypy of the syllable sequence, was higher than that before deafening. The inter-syllable silence was
prolonged. Little change was observed in the songs of intact and sham-operated birds. The significant decrease in high-frequency
syllables and song alteration followed by stabilization resembled the results with songbirds, although song stabilization
took a long time in budgerigars. Therefore, our results suggest that psittacine budgerigars and oscine songbirds require auditory
feedback similarly for adult song maintenance. 相似文献
107.
Jacob M. Vigil 《Human nature (Hawthorne, N.Y.)》2007,18(2):143-161
Several hypotheses on the form and function of sex differences in social behaviors were tested. The results suggest that friendship
preferences in both sexes can be understood in terms of perceived reciprocity potential—capacity and willingness to engage in a mutually beneficial relationship. Divergent social styles may in turn reflect trade-offs
between behaviors selected to maintain large, functional coalitions in men and intimate, secure relationships in women. The
findings are interpreted from a broad socio-relational framework of the types of behaviors that facilitate selective advertisement
and investment of reciprocity potential across individuals and within groups of men and women.
相似文献
Jacob M. VigilEmail: |
108.
Guang Wang Yong Li Jie Li Dongxia Zhang Chao Luo Bingqian Zhang Xiaochuan Sun 《Journal of cellular biochemistry》2019,120(9):15248-15254
microRNAs (miRNAs) can function as a tumor suppressor or oncogenic genes in human cancers. Alternation expression of miR-199a-5p has been revealed in several human cancers. However, its expression pattern and biological roles in glioma remain unclear. Expression levels of miR-199a-5p in glioma were evaluated at first. The effects of miR-199a-5p expression on cell proliferation, migration, and invasion were investigated using the MTT assay, wound-healing assay, and transwell invasion assay. The expression of miR-199a-5p was found to be reduced in glioma cell lines. Overexpression of miR-199a-5p inhibits glioma cell proliferation, migration, and invasion in vitro. Furthermore, the target of miR-199a-5p was predicted by TargetScan and validated by luciferase activity reporter assay. We found magnesium transporter 1 (MAGT1) was a direct target of miR-199a-5p. Overexpression of MAGT1 reversed the effects of miR-199a-5p on glioma cell behaviors. Taken together, our study revealed that miR-199a-5p and MAGT1 have the potential to be used as a biomarker for glioma. 相似文献
109.
110.
C. Shimanoe T. Hachiya M. Hara Y. Nishida K. Tanaka Y. Sutoh A. Shimizu A. Hishida S. Kawai R. Okada T. Tamura K. Matsuo H. Ito E. Ozaki D. Matsui R. Ibusuki I. Shimoshikiryo N. Takashima A. Kadota K. Arisawa H. Uemura S. Suzuki M. Watanabe K. Kuriki K. Endoh H. Mikami Y. Nakamura Y. Momozawa M. Kubo M. Nakatochi M. Naito K. Wakai 《Genes, Brain & Behavior》2019,18(2)
Individuals use coping behaviors to deal with unpleasant daily events. Such behaviors can moderate or mediate the pathway between psychosocial stress and health‐related outcomes. However, few studies have examined the associations between coping behaviors and genetic variants. We conducted a genome‐wide association study (GWAS) on coping behaviors in 14088 participants aged 35 to 69 years as part of the Japan Multi‐Institutional Collaborative Cohort Study. Five coping behaviors (emotional expression, emotional support seeking, positive reappraisal, problem solving and disengagement) were measured and analyzed. A GWAS analysis was performed using a mixed linear model adjusted for study area, age and sex. Variants with suggestive significance in the discovery phase (N = 6403) were further examined in the replication phase (N = 7685). We then combined variant‐level association evidence into gene‐level evidence using a gene‐based analysis. The results showed a significant genetic contribution to emotional expression and disengagement, with an estimation that the 19.5% and 6.6% variance in the liability‐scale was explained by common variants. In the discovery phase, 12 variants met suggestive significance (P < 1 × 10?6) for association with the coping behaviors and perceived stress. However, none of these associations were confirmed in the replication stage. In gene‐based analysis, FBXO45, a gene with regulatory roles in synapse maturation, was significantly associated with emotional expression after multiple corrections (P < 3.1 × 10?6). In conclusion, our results showed the existence of up to 20% genetic contribution to coping behaviors. Moreover, our gene‐based analysis using GWAS data suggests that genetic variations in FBXO45 are associated with emotional expression. 相似文献