Influência de fatores individuais e sociais sobre as respostas endócrina e comportamental de callithrix jacchus a desafios ambientais físicos e sociais

Regarding the growing number of human beings with physical and mental pathologies associated to different stressor agents, attempts are being made to validate animal models with a close phylogenetic resemblance to man, to study stress response. Callithrix jacchus has been widely used in biomedical research, including on stress, but there is scarce information in the literature about how individual and social factors modulate stressor response in this species. This study uses 4 approaches to investigate the response of male and female adult C. jacchus, under situations of stress, and in the first we show evidence of the importance of this animal as an experimental model in research involving the hypothalamus-pituitary-adrenal axis. And we investigate if sex and baseline cortisol levels modulate the behavioral and hormonal response to separation. In two additional approaches investigate if type of social support (co-specific parent or non-parent) and social rank interfere in behavioral and hormonal when the animal are exposure to a new environment, paired with a co-specific (F2), exposure of the animal to a new environment, isolated (F3) or during reunion (F4). Finally, we also investigated the androgen levels in the males, with a focus on the challenge hypothesis, referring to environmental responsiveness and male-male exposure to relatives and non-relatives of C. jacchus. It was observed that: (1) the baseline cortisol of the animal is predictive of cortisol reactivity at separation; (2) males and females do not show dimorphism in the response of cortisol to stressors, although the females have higher baseline levels of this hormone and exhibit higher frequencies of anxiety-related behaviors; (3) only social support provided by relatives proved to be effective in buffering the cortisol response. In behavioral terms this response was dimorphic, showing that only the male dyads displayed an attenuated response to stress; (4) the males showed differences in cortisol levels as a function of social rank and study phases, whereas in the females no such alterations were observed. The males with indefinite dominance hierarchy (IDH) had reduced cortisol in F2 and F4, while the IDH females showed an increase in F3 and F4; (5) the males of relative and non-relative dyads did not exhibit variations in androgen levels as a function of a new environment. These results, taken together, (a) corroborate the use of C. jacchus as a good animal model for stress-related studies, given that they exhibit similar behavioral and physiological alterations to those of human beings in response to stressor agents; (b) point to the importance of considering individual and social modulating factors during experiments with stressors; (c) provide more reliable comparison parameters in studies where these primates are used as animal models, and (d) show that androgens vary as a function of genetic proximity (relative or non-relative) when the animals are faced with physical and social environmental challenges, thus providing important information for studying the challenge hypothesis in this species

Antidepressivos modificam a extinção de uma memória aversiva em ratas

Treatment of major depression, posttraumatic stress disorder and other psychopathologies with antidepressants can be associated with improvement of the cognitive deficits related to these disorders. Although the mechanisms of these effects are not completely elucidated, alterations in extinction of aversive memories are believed to be present in these psychopathologies. Moreover, researches with laboratory animals usually focus on male subjects, and we have recently verified that extinction of an aversive task is reduced in female rats when compared to males. In the present study, female rats were long-term treated with clinically used antidepressants (fluoxetine, nortriptyline or mirtazapine) and tested in the plus-maze discriminative avoidance and forced swimming tests in order to evaluate learning, memory, extinction, anxiety and depression-related behaviors. All groups learned the task, but learning was somewhat faster in nortriptyline and mirtazapine-treated animals . Task retrieval was also showed by all experimental groups. Chronic treatment with fluoxetine, but not with the other antidepressants, increased extinction of the discriminative task. In the forced swimming test, animals treated with fluoxetine and mirtazapine showed decreased immobility duration. In conclusion, antidepressants interfere with learning and female rats treated with fluoxetine presented increased extinction of the aversive memory task. On the other hand, both fluoxetine and mirtazapine were effective in the forced swimming test, suggesting dissociation between the antidepressant effects and the extinction of aversive memories

Avaliação dos efeitos da retirada do etanol em curto e longo prazo sobre respostas comportamentais relacionadas à ansiedade e sobre células imunorreativas para a serotonina no núcleo dorsal da Rafe em ratas

Ethanol withdrawn individuals present a wealth of signs and symptoms, some of them related with anxiety. To better understand brain areas involved in anxiety caused by ethanol abstinence, preclinical studies have been employing models of ethanol consumption followed by withdrawal in rodents submitted to behavioral tests of anxiety, such as the elevated plus-maze. The aim of this study was to investigate if short- or long-term ethanol withdrawal could alter both anxiety-related behaviors in the elevated plus-maze (EPM) and open field tests and the number of serotonin immunorreactive cels in the dorsal raphe nucleus, a midbrain area associated with anxiety. Female Wistar rats (90 days old) were submitted to increasing concentrations of ethanol (2% for 3 days, 4% for 3 days and 6% for 15 days) as the only source of liquid diet and the control group received water ad libitum. Both groups received food ad libitum. In the behavioral experiments, on 21st day of consumption, ethanol was substituted by water (withdrawal) and 72 h or 21 days after withdrawal animals were submitted to the EPM, where it was evaluated the percentage of time and entries in the open arms and the entries in the enclosed arms during 5 minutes. Twenty and four hours after testing in the EPM, animals were submitted to the open field test for 15 minutes, where the distance traveled by the animals was observed along this period. During the first 5 minutes, the distance traveled, entries and time spent in the center of the test were analyzed. In the immunohistochemistry study, animals were submitted to 21 days of consumption of ethanol followed or not by 72 hours and 21 days of withdrawal previously perfusion, brain tissue preparation and quantification of serotonin dyed cells in the dorsal and caudal portions in the dorsal raphe nucleus. Behavioral data showed that both short- and long-term ethanol withdrawals reduced the open arms exploration in the EPM. In the open field test there were no locomotor activity changes during the total 15 minutes; however, longterm ethanol withdrawal reduced the exploration in the center of the open field during the first 5 minutes. In the immunohistochemistry step, there were no differences, when short- and long-term withdrawn groups were compared with control group; nevertheless, the chronic consumption of ethanol decreased the number of serotonergic immunorreactive cells in the dorsal part of dorsal raphe nucleus. Taken together, results here obtained suggest that both short- and long-term ethanol withdrawals promoted an anxiogenic-like effect that was not related with changes in the serotonin immunorreactivity in the dorsal and caudal parts of the dorsal raphe nucleus.

Apitidão funcional e comportamentos relacionados à saúde em mulheres idosas do município de Jequié-BA

The identification of the factors that interfere in the decline of functional conditions is useful in the planning of actions addressing the improvement in the conditions of the lives of elderly people. The purpose of this investigation was to analyze the relationship between social demographics and health aspects of the functional condition in elderly women of low income of the Brazilian northeast. This crosssectional study involved a representative sample of 222 women with an average age of 70 years (± 7.1), belonging to coexisting groups and that were resident in the urban area of the municipal district of Jequié /Bahia. In order to achieve this objective, a battery of physical tests of functional aptitude was carried out previously tested in pilot study, anthropometric measurements collected with a comparison of the measures referred to the reported weight and height as well as the application of an interview with questions containing subjects related to social demographic variables, clinical conditions and health, physical conditions and behaviors. Descriptive statistics Proceedings (frequency, average, standard deviation and percent distribution) were used for statistic analysis, and the calculation of the respective odds ratio by binary logistics regression, for the analysis of factors hierarchically grouped; p<0.05. The prevalence of 56% (n=122) of women considered with moderated or serious type of functional limitations was found, In which from multi-varied hierarchical analysis, significant association was verified with the age group over 80 years (p=0.02), conditions of widowhood (p=0.04), presence of arterial hypertension (p=0.001), and physical inactivity during leisure time (p=0.03). On the other hand for functional incapacities the prevalence was of 46.8% (n=104) being associated to the increase of the age (p=0.01), hospitalization (p=0.02), absence of physical activities along their lives (p=0.001) and the occurrence of alterations in the cognitive function (p=0.001). The normative table for the parameters of physical fitness generated conducive to health professionals in the diagnosis of health conditions and the prescription of physical exercises. The identified characteristics that are associated with the functional limitations / functional incapacities suggest a complex causal net in the determination of the functional condition in elderly women. However, actions addressed to the incentive of the practice of physical activities in the leisure time and the preservation of the cognitive function can contribute to a life with more quality for these people. This research was multidisciplinary approach to involve elements of psychology, nutrition and Physical Education in the elucidation of the object of study related to the functional condition of elderly women

Estilo de vida individual de universitários jovens com excesso de peso da Universidade Católica de Murcia-Espanha

Individual lifestyle includes health and risk behaviors that can altar health status. Excess weight is a public health problem of modern civilization and there is an estimated mean prevalence of 45% in European countries. In Spain, the Murcia Region is an area of high morbidity and mortality from cardiovascular disorders. In this study we assess the differences in health and risk behaviors in ove/weight and normal weight undergraduates at the Universidad Católica San Antonio de Murcia (UCAM). Methods: Transversal design of parallel groups (overweight - cases and normal weight - control) , formed using the anthropometric technique. A questionnaire applied to a sample of 471 undergraduates of either sex, between the ages of 18 and 29 years, enrolled in 4 bachelor degree courses (ADE, CA, PER, PUB) at UCAM. We performed a standardized measurement of body mass (weight in kg), height (in meters) using a Seca® scale with calibrated stadiometer, waist and hip circumferences (in cm) with an inelastic tape and skinfolds thickness (triceps and subscapular in mm) with a Holtain® caliper, to calculate body mass index (BMI), waist-to-hip ratio (WHR) and the sum of skinfolds (SSF). We applied a lifestyle questionnaire about alcohol and tobacco consumption, knowledge and behaviors related to health indicators (arterial pressure and cholesterol), diet and physical activity. The information was collected in April and May, 2001 at the UCAM laboratory of Applied Nutrition. Statistical analysis: analysis of independent groups, contingency tables that reveal which qualitativa variables show differences and associations between the groups, Pearson's chi-square,and a significance levei of p < 0.05 followed by a residual analysis (1.96). Descriptive statistics (mean and standard deviation) were used to establish the two groups: case and contrai with 65 men and 26 women each who had BMI < 25 kg/m2. Results: A total of 65 of the men assessed (14%) and 26 (6%) of the women were overweight. Mean body mass index of the case group was 27. 78 ±: 2.83 kg/m2 in the men and 26.26 ± 1.37 kg/m2 in the women, while contrai group men had mean BMI of 22.36 ± 1.72 kg/m2, while for the women it was 20.76 ±: 2.13 kg/m2. The self-declared values of weight and height were underestimated, but with high accuracy, sensitivity and specificity. Thus, these can be used to calculate the BMI of overweight Spanish undergraduates. Regular vigorous physical activity was observed only in normal weight men. The analysis showed the following significant differences for the qualitativa variables of the two groups. The contrai group was interested in arterial hypertension, believed that they were not overweight, that they had no abdominal fat, and had not considered controlling 'fatty food consumption. Those who thought of controlling it sometimes, did so without professional help. However, part of the overweight group believed that they were overweight and had abdominal fat between average and considerable, had often or always considered controlling fatty foods and had often or always tried to control consumption with the help of professionals. They had always thought of engaging in physical activities, unlike the normal weight individuals. Nearly all (95%) of the overweight undergraduates and most (75%) of the normal weight group reported that they sometimes or always controlled fatty food ingestion. Mean physical activity was nearly twice as high in the summer than in the winter. Conclusions: The overweight undergraduates in this sample displayed a lifestyle with a greater number of healthy behaviors when compared to normal weight individuals

Análise de qualidade da atenção à criança na estratégia saúde da família: o óbito infantil evitável como referência

Alma-Ata declaration bring the Primary Attention to the Health (PAH) as first level of health attention for individuals, family and community, which considers infant group as priority. Several initiatives that gave bases to integral attention to the children health formalized in the principles of Unique Health System. Family Health Strategy (FHS) comes to strengthen this attention, instituting new ways of work organization and professional practices that gave impact in their quality indicators. One of them is children mortality, showing decline in their values. Though, studies indicates persistence of avoidable infant deaths. In Natal RN, this reality is also perceptible leading to inquietudes, mainly at the space of services production, it means, which motivated the accomplishment of the present study intending to analyse the way that the organizational and structural processes as long as the professional practices in FHS interfered in the quality of children s health attention who died by avoidable death in the year of 2007 in municipal district of Natal-RN. It treats, therefore, to an exploratory and descriptive survey of cases study type, thar had as primary sources the oficial documents of MH, the family prontuary, pregnant card, child card and testimony obt ined from instrument of research elaborated based in investigation form of infant death by MH, applied to 10 mothers of children who had avoidable death. In analysis it was appealed silmultaneous triangulation of methods and sources, allowing a bigger aproximation from obtained informations. To elucidate the cases, the aspects studied were analyzed to the light of explicative model of Social Determinants of Health. Among individual and family aspects were highlighted the related to age, schooling, family habits and customs and mother s economic condition, besides of pregnancy age, newborn weight and associated diseases, which don t differ from literature about the theme. Reffering to the factors organizational and structural processes and professionals practice, highlihgted, the treatment given by the professionals, the territorialization and adscription of areas, the difficulty of having access to the services or sleepers and the reference and counterreference. But also, the ausence or few greet, the lack of communication, few assiduity and ponctuality by professionals in service, among others. In a general way mothers considers the attendance received in the hospital good and very good , opnions that in the Basic Attention weren t so favorable, in spite of many of predictible actions in this level have been performed in the studied cases. It is observed, therefore, that the social determinants of health has a strong influence in ocurrence of infant deaths, what implicates in a large actuation by Infant Mortality Committee from municipal district. This way, it becomes fundamental the reflection and evaluation about the effectiveness and execution by the processes of vigilance to health in FHUs; the rethink about the social determinants of health in a wide and articulate way to the services quality, to permanent education, to management in service, to the given attention and to the way how it is installed the popular participation and social control. To the professionals it is presented the great challenge to review their daily practice, their values, behaviors and commitment, which ones must be guided by logical of sharing, work in team, humanescence and alterity, not only by the accomplishment of a professional duty

Composição ictiofaunística e estratégias reprodutivas de quatro espécies de peixes nativos da Bacia Hidrográfica Piranhas - Assu, Rio Grande do Norte

This study focuses on the fish fauna composition and reproductive strategies of four native fish species in relation to environmental variables of the Piranhas-Assu hydrographic basin of the Caatinga biome, Rio Grande do Norte, Brazil. Fish and environmental data were collected monthly during the period September 2008 to February 2010, in the Marechal Dutra reservoir and River Acauã a tributary of Piranhas- Assu. The fish were measured, weighed and dissected, and the gonads were removed, weighed and examined macroscopically for identification and determination of gonad maturation stages. The results of this work generated seven articles. The first article is about the fish fauna composition of the Piranhas-Assu hydrographic basin, Rio Grande do Norte. The 602 fish samples captured were distributed in four orders (Characiformes, Perciformes, Siluriformes and Synbranchiformes), 11 families and 22 species, of which 17 are endemic to the Caatinga ecoregion. The order Characiformes was more representative followed by Perciformes, Siluriformes and Synbranchiformes. The second article is about the length-weight relationship and growth of seven native fish species Crenicichla menezesi, Cichlasoma orientale, Triportheus angulatus, Psectrogaster rhomboides, Pimelodella gracilis, Prochilodus brevis and Leporinus piau from a semiarid Brazilian reservoir. The third article is about the reproductive aspects of Crenicichla menezesi. Males were larger, heavier and with a slight predominance as compared to females. Four stages of gonadal development were characterized, being immature, maturing, mature and spent. The females reached sexual maturity earlier than males, with an average fecundity of 398 oocytes per batch. The spawning was partial with a long reproductive period. The fourth article deals with the reproductive strategy of Leporinus piau a neotropical freshwater fish in semi-arid region of Brazil. The population of L. piau (n = 211) showed a slight predominance of males (55%), with larger and heavier females. The males matured earlier than the females. This species presented total spawning, with an average fecundity of 55,000 mature oocytes. Rainfall and concentration of dissolved oxygen acted as influential factors during the spawning season. L. piau shows a seasonal reproductive strategy. The fifth article is related to the morphometric-meristic characteristics and reproductive aspects of freshwater sardine, Triportheus angulatus from River Acauã of the Caatinga biome. There was a predominance of larger females, reaching first maturation before males. There was total spawning during the rainy period of the region. The sixth article reports on the reproductive strategy of Psectrogaster rhomboides. The sex ratio was 1M: 1F, with negative allometric growth. Males reached sexual maturity earlier than females Females and males showed four stages of gonadal development and spawned during the rainy season. The fecundity was low and this species presented total spawning. The seventh article reports on the dynamics of territorial behavior of Crenicichla menezesi. Ten agonistic behaviors displayed by the males were observed: frontal and lateral threat, chasing, circular chasing, perpendicular, lateral and mouth attacks, escape, parallel positioning and stationary. The formation of four social groups was observed among males: without interaction; interaction with submission and escape; with frontal and lateral agonistic interactions. In social interactions between males and females, it was observed that the larger males interacted more among themselves and with the larger females. The large male established its territory and the two small males along with the small female were excluded from the other groups. These studies clarified the fish fauna composition and reproductive strategies of four native species Crenicichla menezesi, Leporinus piau, Triportheus angulatus and Psectrogaster rhomboides of the Piranhas- Assu hydrographic basin of the Caatinga biome, Rio Grande do Norte, Brazil.

Comportamento alimentar do camarão marinho farfantenaeus subtilis em condições laboratoriais

Shrimp culture represents an important activity to brazilian economy. The northeastern region has presented high levels of production because of its climatic conditions. An important factor for the activity´s major development is related to the introduction of the species Litopenaeus vannamei. The use of an exotic species can disturb the ecosystem. In the last decades, L. vannamei has been the only species cultivated in Brazilian farms, there not being an alternative species for shrimp culture. So, there is an urgent need to developing new studies with the native species, which might represent an alternative concerning shrimp production, with emphasis on Farfantepenaeus subtilis. Another important aspect related to the activity is feeding management, once it is quite usual that feed offer on the pond does not take into account either the species´ physiology and behavior or the influence of environmental variables, such as light cycle and substrate. That knowledge may optimize management and so reduce the impact of effluents in the environment. This study´s objective was characterizing feeding behavior of F. subtilis in laboratory. For that, an ethogram was developed, using 20 wild animals which were observed through ad libitum and all occurrences methods. Two experiments were developed in order to register feeding behavior on different substrates, along 15 days, each. In the first experiment, 40 animals were distributed in eight aquaria, half being observed during the light phase of the 24 hour cycle and the other half in the dark phase, both in halimeda substrate. In the second experiment, 20 animals were distributed in four aquaria, under similar conditions as the previous ones, but in sand substrate. In both experiments, animals were observed respectively one, four, seven and ten hours after the beginning of the phase, for light phase, for the dark phase, in ten minute observation windows, before and immediately after feed offer. The following behaviors were registered: feed ingestion, ingestion of other items, inactivity, exploration, vertical exploration, swimming, crawling, digging, burrowing, and moving by the animals. Observation windows after feed offer also included latency to reach the tray and to ingest feed. Nineteen behaviors were described for the species. F. subtilis presented more behavioral activities in halimeda substrate even in the light phase, while burrowing was predominant in sand substrate. In both substrates, moving, crawling and exploration were more frequent after feed offer, but inactivity and burrowing were more frequent before that. Feed ingestion was more frequent in halimeda, both in light and dark phases. Weight gain was also more prominent in that substrate. In sand substrtate, ingestion was more frequent in the dark phase, which suggests that higher granulometry facilitates feed ingestion in F. subtilis juveniles. Our results demonstrate the importance of studies for the better knowledge of the species, specially its response to environmental stimuli, in order to improve animal management

Adaptação e validação da escala de dependência de exercício físico em versão tradicional e informatizada

While providing physical and psychological benefits, excessive exercise could be or cause a compulsive behavior, making the individual dependent on it. In a parallel discussion, computerized psychological instruments, for a hand, reflects the development of information technology and your applicability to other areas, but also shows little advance for Psychological Assessment. In this perspective, this study aims to adapt the Exercise Dependence Scale (EDS-R) in two formats (paper-and-pencil and computerized) and evaluate evidence of factorial and convergent validity, and reliability of each version and compare them with each other. It is also proposed to observe the relationship of some bio-demographic (Sex, age, frequency, duration and intensity of practice exercise) and the exercise dependence (DEF). For this purpose, 709 regular physical activity practitioners, selected by procedures non-probabilistic sampling, responded a adapted version of EDS-R, Muscle Appearance Satisfaction Scale (MASS), Body Modification Scale (BMS) and a demographic questionnaire, analyzed through Exploratory Factor Analysis, Cronbach's Alpha and not parametric tests. Both the traditional version and the computer showed a seven factors structure, explaining 57 and 62% of the variance, respectively, and Cronbach's alphas of 0.83 and 0.89. Factors were: (1) intentionality, (2) continuity, (3) tolerance, (4) reduction of other activities, (5) lack of control, (6) abstinence and (7) time spent on exercise. Relationships were observed between the Exercise Dependence and the variables: age, diets, consumption of food supplements and medicines for weight change, desire to do plastic surgery and body satisfaction. We observed also a positive correlation between the DEF and the frequency, duration and intensity of exercise, and the factor "Dependence on exercising" from MASS, indicating convergent validity of the EDS-R. Finally, comparisons between the two formats were equivalent, with few changes: computerized version achieved higher DEF scores. Based on these results, it can be concluded that the EDS-R has factorial and convergent validity, reliability, to measure exerceise dependence on traditional e computerized formats. DEF is related to actions used to body modification and behaviors toward exercise. Finally, it was found equivalence between the formats, especially in psychometric parameters, thus suggesting feasibility of a computerized assessment. However, it was observed that the computerized data has sample recruiting strategies more limited

Adolescentes preocupadas em conquistar um corpo magro: Um estudo sobre discursos produzidos em diários eletrônicos

The concern about a good physical condition is heavily present nowadays, in documentary films about health and in the media, and it is also expressed through the outstanding growth of physical academies, beauty institutes and aesthetic medicine and all kind of aesthetic surgeries. In the western world the body wave is a significant trend, characterized by the great investments in body image. However, what is overlooked is the fact that in parallel trend grows the number of teenagers, especially females, with all kind of problems related to their body image. As adolescence is a moment of transformations, teenagers tend to be more aware of their body image and often neglect food ingestion and try to build their bodies following the images they have from top models and movie stars. The low self-esteem accompanying this sort of experience is an additional problem. Therefore the research aim to analyze discourses regarding the body image produced in world wide web diaries (blogs). The blogs selection was made through the site www.blogs.com.br, which is considered the widest guide of electronic diaries in Brazil. We looked after blogs including the keyword body and from adolescents aged 10 to 19, who showed concern about a slim body. Three blogs were chosen, considering the example criteria. Discourse analysis shows that these teenagers feel unsatisfied with their bodies, searching by all means the thinness presented as a aesthetic paradigm in western societies which often implies neglecting their own health, using appetite inhibitor drugs, restricting or totally abstaining food ingestion for long periods of time, or provoking themselves vomits after ingesting food. These behaviors, together with intense fear of gaining weight, can be characterized as alimentary disorders, related to the body image. As they usually hide this sort of behaviors from family and friends who do not share this concern, the blogs seem to be an easy tool for adolescents to find peers with whom to share common values and ideas and reaffirm their identities and virtual sense of community

Sinalização endógena do sistema Nociceptina/Orfanina FQ - receptor NOP: envolvimento na modulação da depressão experimental induzida por lipopolissacarídeo

During the last decades, it has been established that there is a relationship between major depression and activation of immune system. Nociceptin/orphanin FQ (N/OFQ) is the natural ligand of a Gi-protein coupled receptor named NOP, both compose the peptidergic system wich is involved in the regulation of mood states and inflammatory responses. Considering these actions, the present thesis aimed to investigate the consequences of blocking NOP signaling in lipopolysaccharide (LPS)-induced sickness and depressive-like behaviors in mice. Systemic administration of LPS doses, that do not cause sepsis in mice, induce changes in their behaviors related with activity of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukins 6 (IL-6) and 1β (IL-1 β). At the time points of 2 to 6 h and 24 h after intraperitoneal injection, mice treated with LPS displayed, respectively, sickness and depressive-like behaviors. In the present work the administration of LPS 0.8 mg/kg (ip) significantly induced sickness signs in Swiss and CD-1 mice, such as weight loss, transient reduction in rectal temperature and decrease of food and water intake. Moreover at 24 h after LPS injection these same mice strains displayed significantly increased immobility time on the tail suspension test (TST) when compared with control mice, this alteration was not related with possible locomotion impairments as verified on the open field test. Treatment with Nortriptyline 30 mg/kg (ip, 60 min prior the TST) reduced the immobility time of control and LPS-treated mice and was used as standard antidepressant. The NOP receptor antagonist SB-612111 (10 mg/kg, ip), 30 min prior LPS, did not modify LPS-induced sickness signs and depressive-like behavior. However, when injected 24 h after LPS treatment, SB-612111 (ip, 30 min prior the TST) as well as the peptidergic NOP receptor antagonist UFP-101 (10 nmol/2μL, icv, 5 min prior the TST) significantly reversed the toxin effects. The protocol of LPS-induced depressive-like states was also tested in NOP receptor knockout mice (NOP(-/-)) and their respective wild types (NOP(+/+)). LPS evoked transient rectal temperature reduction in NOP(-/-) mice and loss of body weight, food and water intake reduction in both NOP(+/+) and NOP(-/-) mice. The consumption of water was significantly different due to the genotype. LPS injection induced transient changes in pro-inflammatory cytokines. At 6 h after LPS injection, serum levels of TNF-α were significantly increased in NOP(+/+) and NOP(-/-) mice, as the IL-6 levels were significantly increased just in NOP(+/+) serum. At 24 h after LPS treatment the pro-inflammatory cytokines had returned to the baseline levels in both genotypes. LPS treatment elicited depressive-like effects in NOP(+/+) but not in NOP(-/-) mice. The data obtained during the execution of this doctoral thesis reveal that pharmacological and genetic blockade of NOP signaling does not affect LPS evoked sickness signs while reversing depressive-like behavior. In conclusion, these results highlight the involvement of the peptidergic system N/OFQ - NOP receptor in the modulation of behaviors related to mood and activation of the immune system.