急性恐惧应激对大鼠行为、激素水平及脑Erk1/2活化表达的影响

目的:探讨急性恐惧应激对大鼠情感行为、激素水平及不同脑区Erk1/2活化表达的影响。方法:采用足电击 白噪声刺激方式建立急性恐惧应激大鼠模型,观察其情感行为的改变;放射免疫法及荧光分光光度法检测血浆和脑组织激素水平;Westernblot检测Erk1/2的活化表达。结果:应激后大鼠旷场活动性降低、拒俘反应性增加、惊吓反应增强(P<0.01);血浆及脑组织去甲肾上腺素、5-羟色胺、皮质醇水平增高,而肾上腺髓质素水平降低(P<0.01);海马、纹状体、前额皮质、小脑等脑区磷酸化Erk1/2蛋白的表达均显著增高(P<0.01)。结论:急性恐惧应激可以显著影响大鼠的情感行为和激素水平,Erk1/2蛋白磷酸化水平的增高可能参与了急性恐惧应激所致的情感行为异常。     

A genome‐wide association study of coping behaviors suggests FBXO45 is associated with emotional expression

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.     

Regulation of emotional memory by hydrogen sulfide: role of GluN2B‐containing NMDA receptor in the amygdala

As an endogenous gaseous molecule, hydrogen sulfide (H₂S) has attracted extensive attention because of its multiple biological effects. However, the effect of H₂S on amygdala‐mediated emotional memory has not been elucidated. Here, by employing Pavlovian fear conditioning, an animal model widely used to explore the neural substrates of emotion, we determined whether H₂S could regulate emotional memory. It was shown that the H₂S levels in the amygdala of rats were significantly elevated after cued fear conditioning. Both intraamygdala and systemic administrations of H₂S markedly enhanced amygdala‐dependent cued fear memory in rats. Moreover, it was found that H₂S selectively increased the surface expression and currents of NMDA‐type glutamate receptor subunit 2B (GluN2B)‐containing NMDA receptors (NMDARs) in lateral amygdala of rats, whereas blockade of GluN2B‐containing NMDARs in lateral amygdala eliminated the effects of H₂S to enhance amygdalar long‐term potentiation and cued fear memory. These results demonstrate that H₂S can regulate amygdala‐dependent emotional memory by promoting the function of GluN2B‐containing NMDARs in amygdala, suggesting that H₂S‐associated signaling may hold potential as a new target for the treatment of emotional disorders.

     

Circadian and age-related changes in stress responsiveness of the adrenal cortex and erythrocyte antioxidant enzymes in female rhesus monkeys

Background The objective of this study was to evaluate the role of the adrenal cortex in the regulation of antioxidant enzyme defense and to characterize this regulation in different age periods. Methods Five young and five old female rhesus monkeys were subjected to 2 hours squeeze cage restraint stress at 0900 or 1500 hours. Plasma levels of corticosteroids and activities of erythrocyte antioxidant enzymes were measured before the stress and 30, 60, 120, 240 minutes after beginning of the stress. Results Young monkeys showed a circadian rhythm in stress responsiveness as measured by corticosteroids and glutathione reductase. The rhythm was attenuated in old animals. Age‐related changes in the overall level of response to the afternoon stress were also seen in the corticosteroid and glutathione reductase measures. Conclusions The study demonstrated that corticosteroids play an essential role in the regulation of antioxidant enzyme defense in stress conditions and that the reliability of their regulation decreases with age.     

Rapid facial mimicry in orangutan play

Emotional contagion enables individuals to experience emotions of others. This important empathic phenomenon is closely linked to facial mimicry, where facial displays evoke the same facial expressions in social partners. In humans, facial mimicry can be voluntary or involuntary, whereby its latter mode can be processed as rapid as within or at 1s. Thus far, studies have not provided evidence of rapid involuntary facial mimicry in animals.This study assessed whether rapid involuntary facial mimicry is present in orangutans (Pongo pygmaeus; N=25) for their open-mouth faces (OMFs) during everyday dyadic play. Results clearly indicated that orangutans rapidly mimicked OMFs of their playmates within or at 1s. Our study revealed the first evidence on rapid involuntary facial mimicry in non-human mammals. This finding suggests that fundamental building blocks of positive emotional contagion and empathy that link to rapid involuntary facial mimicry in humans have homologues in non-human primates.     

How contexts promote and prevent relapse to drug seeking

The contexts where drugs are self‐administered play an important role in regulating persistent drug taking and in relapse to such taking after periods of abstinence. Here, we review the behavioral and brain mechanisms enabling contexts to promote and prevent relapse to drug seeking. We review the key brain structures, their neuropharmacology and their connectivity. We discuss the similarities and differences between the mechanisms for context‐induced reinstatement of drug seeking vs. other forms of relapse to drug seeking in animal models and we highlight the numerous deficits in our understanding. We emphasize that current understanding, although significant, defies explanations in terms of models at the level of brain structures and their connectivity. Rather, we show that there is significant functional compartmentalization and segregation within these structures during reinstatement and extinction of drug seeking that parallels their anatomical segregation into circuits and channels. A key challenge is to recognize this complexity, understand how these circuits and channels are organized, as well as understand how different modes of activity of ensembles of neurons within them promote abstinence or relapse to drug seeking.     

公立医院职场排斥对护士情绪耗竭和工作满意度的影响

目的 探讨公立医院职场排斥对护士情绪耗竭和工作满意度的影响以及可能的机制。方法 采用横断面问卷调查法收集数据,采用多元阶层回归分析法进行数据统计分析。结果 职场排斥得分均值为（1.53±0.72）,处于较低水平;52.2%护士表现出情绪耗竭倾向;职场排斥能够显著预测护士的情感耗竭（β=0.186,P＜0.01）和工作满意度（β= -0.252,P＜0.01）。其中,情绪耗竭在二者之间扮演部分中介作用。结论 公立医院职场排斥在护理人群中并不普遍,但却应该引起关注;护士情绪耗竭较为严重。而且,职场排斥将直接或者通过情绪耗竭中介作用影响她们的工作满意度评价。     

Individuality of distress and discomfort calls in neonates with bass voices: Wild‐living goitred gazelles (Gazella subgutturosa) and saiga antelopes (Saiga tatarica)

Neonate ruminants produce distress calls when captured by a predator and discomfort milk begging calls when hungry. In many neonate ruminants, the distress and discomfort calls are high‐frequency vocalizations, in which the fundamental frequency is the key variable for recognition of their emotional arousal by caregivers. In contrast, in this study, we examine the low‐frequency open‐mouth distress and discomfort calls in the neonates of two species of wild‐living ungulates, which clearly highlight vocal tract resonances (formants). In the goitred gazelle (Gazella subgutturosa), the distress calls were higher in fundamental frequency (f0) and in the first and third formants than the discomfort calls. The accuracy of classifying individuals by variables of distress calls with discriminant function analysis (67%) was significantly lower than that of discomfort calls (85%). In the saiga (Saiga tatarica), only the third formant was higher in the distress calls than in the discomfort calls. The accuracy of classifying individuals by variables of distress calls (89%) did not differ significantly from that of discomfort calls (94%). Thus, the use of acoustic cues to vocal identity and to the degree of arousal differs between the two species. Calls were significantly more individualistic in the saiga, probably because this species lives in large herds and neonates use a ‘following’ antipredatory strategy, in which vocal individuality is crucial for mother–offspring communication. In contrast, goitred gazelles live in smaller groups and neonates use a ‘hiding’ antipredatory strategy. Accordingly, mothers can rely on additional environmental cues for spotting their young and this may decrease the necessity for individualization of the calls of neonates.     

Discomfort-related changes in pup ultrasonic calls of fat-tailed gerbils Pachyuromys duprasi

Rodent pups vocalize when placed in social isolation. We apply a method of “joint calls” for examining discomfort in rodent pup ultrasonic (>20 kHz) calls. Previously, this method has been developed for audible calls of fur farm mammals. Using a repeated measures design to exclude effects of individual identity and age on the analysed variables, we compared the ultrasonic call variables produced by 8–40-day pups of fat-tailed gerbils Pachyuromys duprasi during two subsequent experimental stages, the Isolation Stage and the Handling Stage. We considered that discomfort-related negative emotional arousal increased towards the Handling Stage compared to the Isolation Stage because of cumulative effects of handling and time of pup isolation from the nest. At the Isolation Stage, the call rate (calls/s) was higher from 10 to 18 days of age, whereas both the maximum amplitude frequency and power quartiles of joint calls were lower than at the Handling Stage from 20 to 32 days of age. At the same time, in audible (<20 kHz) vocalizations of a wide range of mammalian species, both the higher call rate and the upward shift of the maximum amplitude frequency and power quartiles indicate the discomfort-related increase of negative emotional arousal. We discuss the advantages of the method of joint calls for express-analyses of power variables for large sequences of ultrasonic vocalizations of complex acoustic structure during experimental trials.     

Prescribed “Breaks” as a Means to Disrupt Weight Control Efforts

Objective: Research on long‐term maintenance of weight loss is hampered by the fact that relapse typically does not occur until after 6 months. We sought to determine whether relapses could be induced earlier by intentionally interrupting the momentum of weight loss during a treatment program and thus provide a model for weight maintenance research. Research Methods and Procedures: Subjects (N = 142) were recruited at two centers and randomly assigned to a control group, a long break group (LB), or a short break group (SB). The control group received a standard behavioral weight loss program with 14 weekly sessions; the LB and SB groups received the same. However, the LB group took a 6‐week break after lesson 7, and the SB group took a 2‐week break after lessons 3, 6, and 9. Participants were instructed to stop all weight loss efforts during breaks. Results: Participants seemed to take breaks as prescribed, with interruptions in self‐monitoring, dietary adherence, and self‐weighing (but not in exercise). However, participants quickly resumed these behaviors after the break. Breaks produced a slowing of weight loss or slight regain, but weight losses during the breaks were not significantly different from the control group. Importantly, overall weight losses (0 to 5 months or 0 to 11 months) did not differ between conditions. Discussion: This study was not successful in developing a method to experimentally produce weight loss relapses. However, the finding that prescribed breaks do not have adverse effects may have clinical application.