RESUMO
Species that live in degraded habitats often show signs of physiological stress. Glucocorticoid hormones (e.g., corticosterone and cortisol) are often assessed as a proxy of the extent of physiological stress an animal has experienced. Our goal was to quantify glucocorticoids in free-ranging small mammals in fragments of Interior Atlantic Forest. We extracted glucocorticoids from fur samples of 106 small mammals (rodent genera Akodon and Oligoryzomys, and marsupial genera Gracilinanus and Marmosa) from six forest fragments (2-1200 ha) in the Reserva Natural Tapytá, Caazapá Department, Paraguay. To our knowledge, this is the first publication of corticosterone and cortisol levels for three of the four sampled genera (Akodon, Oligoryzomys, and Marmosa) in this forest system. We discovered three notable results. First, as predicted, glucocorticoid levels were higher in individuals living withing small forest fragments. Second, animals captured live using restraint trapping methods (Sherman traps) had higher glucocorticoid levels than those animals captured using kill traps (Victor traps), suggesting that hair glucocorticoid measures can reflect acute stress levels in addition to long-term glucocorticoid incorporation. These acute levels are likely due to urinary steroids diffusing into the hair shaft. This finding raises a concern about the use of certain trapping techniques in association with fur hormone analysis. Finally, as expected, we also detected genus-specific differences in glucocorticoid levels, as well as cortisol/corticosterone ratios.
Assuntos
Pelo Animal/química , Corticosterona/análise , Florestas , Glucocorticoides/análise , Hidrocortisona/análise , Marsupiais/classificação , Roedores/classificação , Animais , Biodiversidade , Feminino , Masculino , Paraguai , Estresse FisiológicoRESUMO
This study investigated neuroendocrine, autonomic, and cardiovascular changes evoked by daily exposure to the same type of stressor (homotypic) or different aversive stressor stimuli (heterotypic) in 60-days-old female normotensive Wistar rats and female spontaneously hypertensive rats (SHR). Both strains of rats were exposed for 10 consecutive days to either the homotypic stressor repeated restraint stress (RRS) or the heterotypic stressor chronic unpredictable stress (CUS). As expected, SHR had higher baseline blood pressure values and impaired baroreflex activity in relation to normotensive animals. Besides, SHR presented higher plasma corticosterone levels and decreased thymus weight. Both RRS and CUS increased baseline plasma corticosterone concentration and decreased body weight gain in both normotensive and SHR rats. In addition, both stress protocols caused hypertrophy of adrenal glands in normotensive rats. Regarding the cardiovascular effects, RRS increased basal heart rate in both rat strains, which was mediated by an increase in sympathetic tone to the heart. Besides, RRS increased baroreflex-mediated tachycardia in SHR animals, while CUS increased cardiac parasympathetic activity and pacemaker activity in normotensive rats. Taken together, these results indicate a stress type-specific effect, as identified by a vulnerability of both strains to the deleterious cardiovascular effects evoked by the homotypic stressor and a resilience to the impact of the heterotypic stressor. Vulnerability of hypertensive rats was evidenced by the absence of CUS-evoked adaptive cardiovascular responses and an increase of baroreflex tachycardia in SHR animals subjected to RRS. The somatic and HPA axis changes were overall independent of the chronic stress regimen and pre-existing hypertension.
Assuntos
Hipertensão/fisiopatologia , Estresse Psicológico/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/fisiopatologia , Doença Crônica/psicologia , Corticosterona/análise , Feminino , Frequência Cardíaca/fisiologia , Hipertensão/complicações , Sistema Hipotálamo-Hipofisário , Células Neuroendócrinas/fisiologia , Sistemas Neurossecretores/fisiopatologia , Sistema Hipófise-Suprarrenal , Cobertura de Condição Pré-Existente , Ratos , Ratos Endogâmicos SHR , Ratos WistarRESUMO
Early life stress (ELS) affects hippocampal neurogenesis, increases depressive-like behavior, and causes mild metabolic imbalance in early adulthood (2 months). However, whether these effects worsen in mid life remains unclear. To test whether age-dependent effects of ELS on hippocampal neurogenesis are related to deficient hypothalamic-pituitary-adrenal (HPA) axis feedback that causes increased comorbidity of depression and metabolic risk, we evaluated the effects of periodic maternal separation (MS180) in young (4-months-old) and middle-aged (10-months-old) adult rats. MS180 caused more severe depressive-like behavior in middle-aged adults than in young animals. There were no behavioral phenotypic differences between young MS180 and control middle-aged groups. MS180 similarly affected glucose tolerance, increased fasting corticosterone, insulin, and the quantitative insulin sensitivity check index (QUICKI) at both ages. However, middle-aged adult MS180 rats showed more severe age-induced obesity (>40% BW) than controls (>22% BW). MS180 differentially affected dorsal and ventral neurogenesis. In young adults, MS180 animals only showed a decrease in dorsal hippocampal neurogenesis as compared to their age-matched counterparts. In contrast, at 10 months of age, MS180 caused a similar decrease in both dorsal and ventral hippocampal neurogenesis as compared to age-matched controls, and a more severe decrease as compared to young animals. Taken together, our data indicate that MS180 animals show an early onset of age-induced alterations on depression and metabolic risk, and these effects relate to alterations in hippocampal neurogenesis.
Assuntos
Depressão , Neurogênese , Estresse Psicológico , Animais , Feminino , Masculino , Gravidez , Ratos , Fatores Etários , Comportamento Animal/fisiologia , Corticosterona/análise , Depressão/metabolismo , Depressão/fisiopatologia , Modelos Animais de Doenças , Proteína Duplacortina , Glucocorticoides/análise , Hipocampo/metabolismo , Sistema Hipotálamo-Hipofisário , Privação Materna , Neurogênese/fisiologia , Sistema Hipófise-Suprarrenal , Ratos Sprague-Dawley , Estresse Psicológico/fisiopatologiaRESUMO
The aim of this study was to compare the effects of beak trimming by hot blade or infrared radiation on production indicators and plasma levels of corticosterone in pullets. During the rearing phase, an entirely random delineation was used a 2 x 3 factorial design (two different techniques for beak trimming x 3 strains), a total of six treatments with six repetitions of 20 hens. In the growing phase, the previous treatments were divided into 12, with eight repetitions with seven hens. These treatments were then distributed in a factorial design of 2 x 3 x 2 (two methodologies for beak trimming during rearing phase x three strains x with or without beak trimming at ten weeks of age). In the rearing phase the birds treated by infrared radiation had a lower total consumption and a longer beak length. In the growing phase, the execution of beak trimming at ten weeks of age, led to a lower total consumption and a lower body weight, but a better food conversion, when compared to those hens that did not have beak treatment. Beak trimming at ten weeks did not change the plasmatic levels of corticosterone.(AU)
Assuntos
Animais , Corticosterona/análise , Corticosterona/síntese química , Aves Domésticas/metabolismo , Bem-Estar do AnimalRESUMO
The aim of this study was to compare the effects of beak trimming by hot blade or infrared radiation on production indicators and plasma levels of corticosterone in pullets. During the rearing phase, an entirely random delineation was used a 2 x 3 factorial design (two different techniques for beak trimming x 3 strains), a total of six treatments with six repetitions of 20 hens. In the growing phase, the previous treatments were divided into 12, with eight repetitions with seven hens. These treatments were then distributed in a factorial design of 2 x 3 x 2 (two methodologies for beak trimming during rearing phase x three strains x with or without beak trimming at ten weeks of age). In the rearing phase the birds treated by infrared radiation had a lower total consumption and a longer beak length. In the growing phase, the execution of beak trimming at ten weeks of age, led to a lower total consumption and a lower body weight, but a better food conversion, when compared to those hens that did not have beak treatment. Beak trimming at ten weeks did not change the plasmatic levels of corticosterone.
Assuntos
Animais , Aves Domésticas/metabolismo , Bem-Estar do Animal , Corticosterona/análise , Corticosterona/síntese químicaRESUMO
Steroid hormone assessment using non-invasive sample collection techniques can reveal the reproductive status of aquatic mammals and the physiological mechanisms by which they respond to changes in their environment. A portion of the eastern North Pacific blue whale (Balaenoptera musculus) population that seasonally visits the Gulf of California, Mexico has been monitored using photo-identified individuals for over 30â¯years. The whales use the area in winter-early spring for nursing their calves and feeding and it therefore is well suited for fecal sample collection. Using radioimmunoassays in 25 fecal samples collected between 2009 and 2012 to determine reproductive state and stress, we validated three steroid hormones (progesterone, corticosterone and cortisol) in adult female blue whales. Females that were categorized as pregnant had higher mean fecal progesterone metabolite concentrations (1292.6⯱â¯415.6â¯ng·g-1) than resting and lactating females (14.0⯱â¯3.7â¯ng·g-1; 23.0⯱â¯5.4â¯ng·g-1, respectively). Females classified as pregnant also had higher concentrations of corticosterone metabolites (37.5⯱â¯9.9â¯ng·g-1) than resting and lactating females (17.4⯱â¯2.0â¯ng·g-1; 16.8⯱â¯2.8â¯ng·g-1, respectively). In contrast, cortisol metabolite concentrations showed high variability between groups and no significant relationship to reproductive state. We successfully determined preliminary baseline parameters of key steroid hormones by reproductive state in adult female blue whales. The presence of pregnant or with luteal activity and known lactating females confirms that the Gulf of California is an important winter-spring area for the reproductive phase of these blue whales. The baseline corticosterone levels we are developing will be useful for assessing the impact of the increasing coastal development and whale-watching activities on the whales in the Gulf of California.
Assuntos
Balaenoptera/fisiologia , Fezes/química , Hormônios Esteroides Gonadais/análise , Reprodução/fisiologia , Animais , Balaenoptera/metabolismo , California , Corticosterona/análise , Corticosterona/metabolismo , Feminino , Hormônios Esteroides Gonadais/metabolismo , Gravidez , Progesterona/análise , Progesterona/metabolismo , Radioimunoensaio , Manejo de EspécimesRESUMO
In many species, chronic stress due to overcrowding during the juvenile period triggers several metabolic and behavioral pathologies in adulthood. The aim of this study was to determine whether a chronic stress condition (overcrowding) induces changes in plasma and hair corticosterone concentrations, overall growth, and organ weights in young Wistar rats. The experimental subjects were divided into 2 groups (control and overcrowded); the overcrowded subjects were exposed to overcrowding during days 38 through 65 after birth. Plasma and hair corticosterone concentrations were higher in overcrowded rats compared with control subjects. In addition, overcrowding reduced body and organ weight gains. These results demonstrate that measuring the concentration of corticosterone in hair samples is an effective, noninvasive method for monitoring chronic stress in rats.
Assuntos
Corticosterona/análise , Abrigo para Animais , Ratos/fisiologia , Estresse Fisiológico , Bem-Estar do Animal , Animais , Corticosterona/sangue , Cabelo/química , Masculino , Tamanho do Órgão , Ratos/crescimento & desenvolvimento , Ratos Wistar , TerritorialidadeRESUMO
Amphibian metamorphosis is complex and larval morphology and physiology are completely restructured during this time. Amphibians that live in unpredictable environments are often exposed to stressors that can directly and indirectly alter physiological systems during development, with subsequent consequences (carryover effects) later in life. In this study, we investigated the effects of water level reduction on development rate, spleen size and cellularity, and examined the role of corticosterone levels in premetamorphic, metamorphic, and postmetamorphic New Mexico spadefoot toads (Spea multiplicata). Based on previous studies, we hypothesized that declining water level would increase tadpole developmental rate, but with the trade-off of increasing corticosterone to a level that would subsequently affect spleen size and cellularity, thus prolonging potential immunological suppression. Declining water levels increased developmental rate by 3 days; however, there were no significant body size effects. Corticosterone (CORT) was negatively correlated with total length, snout vent length, body weight, and spleen weight at metamorphosis, suggesting that size at metamorphosis and the immune system may be affected by excessive CORT levels. When compared to other studies, our results support the view that multiple factors may be acting as stressors in the field affecting amphibian responses, and simple pathways as tested in this study may not adequately represent field conditions.
Assuntos
Anuros/crescimento & desenvolvimento , Metamorfose Biológica , Baço/anatomia & histologia , Estresse Fisiológico , Água , Animais , Anuros/fisiologia , Corticosterona/análise , Feminino , Sistema Imunitário , Masculino , Tamanho do Órgão , Baço/crescimento & desenvolvimentoRESUMO
Many environmental conditions elevate plasma corticosterone in laying birds, leading to elevated hormone accumulation in the egg. We investigated whether maternal yolk corticosterone levels in Greater Rheas differ between fresh eggs collected from an intensive (IRS) and a semi-extensive (SRS) rearing system. After HPLC validation, yolk corticosterone was measured using a corticosterone (125) I radio-immunoassay kit. Results (mean ± SE) showed that eggs collected from the IRS exhibited a significantly higher corticosterone concentration than eggs from SRS (89.88 ± 8.93 vs. 45.41 ± 5.48 ng/g yolk, respectively). Our findings suggest that rearing conditions under an intensive scheme (e.g., small pens with bare ground, no direct foraging and handling) might be perceived as more stressful for Greater Rhea females than semi-extensive rearing conditions (e.g., low animal density distributed in extensive areas and direct foraging), which would result in the transfer of higher yolk corticosterone levels. A better understanding of environmental conditions and female traits that affect yolk corticosterone deposition provides a background for future studies concerning the roles of maternal corticosterone on offspring development. Zoo Biol. 35:246-250, 2016. © 2016 Wiley Periodicals, Inc.
Assuntos
Animais de Zoológico/fisiologia , Corticosterona/metabolismo , Gema de Ovo/química , Meio Ambiente , Reiformes/fisiologia , Estresse Fisiológico/fisiologia , Criação de Animais Domésticos/normas , Animais , Corticosterona/análise , Feminino , Reiformes/metabolismoRESUMO
Exposure to adverse environmental conditions can elicit a stress response, which results in an increase in endogenous corticosterone levels. In early life stages, it has been thoroughly demonstrated that amphibian larval growth and development is altered as a consequence of chronic stress by interfering with the metamorphic process, however, the underlying mechanisms involved have only been partially disentangled. We examined the effect of intraspecific competition on corticosterone levels during larval development of the toad Rhinella arenarum and its ultimate effects on cell proliferation in particular brain areas as well as the pituitary gland. While overcrowding altered the number of proliferating cells in the pituitary gland, hypothalamus, and third ventricle of the brain, no differences were observed in areas which are less associated with neuroendocrine processes, such as the first ventricle of the brain. Apoptosis was increased in hypothalamic regions but not in the pituitary. With regards to pituitary cell populations, thyrotrophs but not somatoatrophs and corticotrophs showed a decrease in the cell number in overcrowded larvae. Our study shows that alterations in growth and development, produced by stress, results from an imbalance in the neuroendocrine systems implicated in orchestrating the timing of metamorphosis.
Assuntos
Encéfalo/crescimento & desenvolvimento , Bufo arenarum/crescimento & desenvolvimento , Proliferação de Células , Aglomeração , Sistemas Neurossecretores/crescimento & desenvolvimento , Hipófise/crescimento & desenvolvimento , Estresse Fisiológico , Animais , Apoptose , Encéfalo/citologia , Corticosterona/análise , Larva/citologia , Larva/crescimento & desenvolvimento , Metamorfose Biológica , Sistemas Neurossecretores/citologia , Hipófise/citologiaRESUMO
The Swiss Webster mice of the strain in animal facilities are individually and interesting and complex social behavior. The aggressiveness of adult male has varying intensity and is associated with hierarchical dominance. In approximately 5% of the animals we observed an exacerbation of aggressive behavior and the presence of severe damage to the other components of the group. Our goal in this work is to search to correlate the level of plasma corticosterone and their phenotypic behavioral categories: Har - the absence of aggressiveness; AgD - attacked and AgR animals - aggressive individuals, compared with the previous values to the regrouping (BfR). Our results demonstrate that the regrouping of adult male individuals is a stressor that promotes and decreased weight gain in categories and Har AgD and weight loss in individuals AgR. Furthermore, the values of plasma corticosterone rises in the first two categories, but is maintained in the category AgR. So, we believe that the exacerbation and / or uncontrolled aggression in some individuals is related to a Posttraumatic Stress Disorder (PTSD) characterized by sustained activation of the Hypothalamic-Pituitary-Adrenal (HPA) and the inability of the animal in dealing with new stress situations. (AU)
O camundongo da linhagem Swiss Webster em biotérios apresentam um interessante e complexo repertório de comportamentos individuais e sociais. A agressividade de machos adultos apresenta intensidade variável e está associada a dominância hierárquica. Em aproximadamente 5% dos animais observamos uma exacerbação do comportamento agressivo e a presença de graves lesões por lutas e mordidas nos demais componentes do grupo. Nosso objetivo nesse trabalho é buscar correlacionar o nível de corticosterona plasmática e as respectivas categorias fenotípicas comportamentais: Har ausência de agressividade; AgD animais agredidos e AgR indivíduos agressores, sendo comparados com o valores anteriores ao reagrupamento (BfR). Nossos resultados demonstram que o reagrupamento de indivíduos machos adultos é um agente estressor e que promove diminuição do ganho de peso nas categorias Har e AgD e perda de peso nos indivíduos AgR. Além disso, os valores médios de corticosterona plasmática eleva-se nas duas primeiras categorias, porém é mantida na categoria AgR. Então, acreditamos que a exacerbação e/ou descontrole da agressividade em alguns indivíduos esteja relacionado a um TEPT caracterizado pela ativação contínua do HHA e a incapacidade do animal em lidar com novas situações de estresse. (AU)
Assuntos
Animais , Camundongos , Corticosterona/administração & dosagem , Corticosterona/análise , Comportamento Animal , FenótipoRESUMO
The Swiss Webster mice of the strain in animal facilities are individually and interesting and complex social behavior. The aggressiveness of adult male has varying intensity and is associated with hierarchical dominance. In approximately 5% of the animals we observed an exacerbation of aggressive behavior and the presence of severe damage to the other components of the group. Our goal in this work is to search to correlate the level of plasma corticosterone and their phenotypic behavioral categories: Har - the absence of aggressiveness; AgD - attacked and AgR animals - aggressive individuals, compared with the previous values to the regrouping (BfR). Our results demonstrate that the regrouping of adult male individuals is a stressor that promotes and decreased weight gain in categories and Har AgD and weight loss in individuals AgR. Furthermore, the values of plasma corticosterone rises in the first two categories, but is maintained in the category AgR. So, we believe that the exacerbation and / or uncontrolled aggression in some individuals is related to a Posttraumatic Stress Disorder (PTSD) characterized by sustained activation of the Hypothalamic-Pituitary-Adrenal (HPA) and the inability of the animal in dealing with new stress situations.
O camundongo da linhagem Swiss Webster em biotérios apresentam um interessante e complexo repertório de comportamentos individuais e sociais. A agressividade de machos adultos apresenta intensidade variável e está associada a dominância hierárquica. Em aproximadamente 5% dos animais observamos uma exacerbação do comportamento agressivo e a presença de graves lesões por lutas e mordidas nos demais componentes do grupo. Nosso objetivo nesse trabalho é buscar correlacionar o nível de corticosterona plasmática e as respectivas categorias fenotípicas comportamentais: Har ausência de agressividade; AgD animais agredidos e AgR indivíduos agressores, sendo comparados com o valores anteriores ao reagrupamento (BfR). Nossos resultados demonstram que o reagrupamento de indivíduos machos adultos é um agente estressor e que promove diminuição do ganho de peso nas categorias Har e AgD e perda de peso nos indivíduos AgR. Além disso, os valores médios de corticosterona plasmática eleva-se nas duas primeiras categorias, porém é mantida na categoria AgR. Então, acreditamos que a exacerbação e/ou descontrole da agressividade em alguns indivíduos esteja relacionado a um TEPT caracterizado pela ativação contínua do HHA e a incapacidade do animal em lidar com novas situações de estresse.
Assuntos
Animais , Camundongos , Comportamento Animal , Corticosterona/administração & dosagem , Corticosterona/análise , FenótipoRESUMO
BACKGROUND: Hyperthyroidism (Hy) exerts a broad range of influences on a variety of physiological parameters. Its disruptive effect on cardiovascular system is one of its most remarkable impacts. Moreover, Hy has been clinically associated with stress - induced hyperactivation of the hypothalamic-pituitary-adrenal axis. OBJECTIVE: Evaluate the impact of short-term Hy on cardiac performance and adrenal activity of rats. METHODS: Induction of Hy in Wistar rats through injections of T3 (150 µg/kg) for 10 days (hyperthyroid group - HG) or vehicle (control group). The cardiovascular performance was evaluated by: echocardiography (ECHO); heart weight/body weight (mg/gr) ratio; contractility of isolated papillary muscles (IPM) and direct measurement of blood pressures. Adrenal activity was evaluated by adrenal weight/body weight (mg/gr) ratio and 24-hour fecal corticosterone (FC) levels on the, 5th and 10th days of T3 treatment. RESULTS: In HG, the ECHO showed reduction of the End Systolic and End Diastolic Volumes, Ejection, Total Diastolic and Isovolumic Relaxation Times, Diastolic and Systolic Areas and E/A ratio. Heart Rate, Ejection Fraction and Cardiac Output increased. The heart weight/body weight ratio was higher. Similarly, in IPM, the maximum rate of force decay during relaxation was higher in all extracellular calcium concentrations. Systolic blood pressure (SBP) levels were higher. (p ≤ 0.05). On the other hand, there was no difference in the adrenal weight/body weight ratio or in the 24-hour FC levels. CONCLUSIONS: Hy induces positive inotropic, chronotropic and lusitropic effects on the heart by direct effects of T3 and increases SBP. Those alterations are not correlated with changes in the adrenal activity.
Assuntos
Glândulas Suprarrenais/fisiopatologia , Coração/fisiopatologia , Hipertireoidismo/complicações , Hipertireoidismo/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Corticosterona/análise , Modelos Animais de Doenças , Ecocardiografia , Frequência Cardíaca/fisiologia , Masculino , Músculos Papilares/fisiopatologia , Ratos Wistar , Valores de Referência , Tiroxina/análise , Fatores de Tempo , Tri-Iodotironina/análiseRESUMO
Fundamento: O hipertireoidismo (Hi) exerce um amplo leque de influências em diversos parâmetros fisiológicos. Seu efeito perturbador sobre o sistema cardiovascular é um de seus impactos mais importantes. Além disso, o Hi foi clinicamente associado com o estresse induzido pela hiperativação do eixo hipotalâmico-pituitário-adrenal. Objetivo: Avaliar o impacto do Hi de curto prazo sobre o desempenho cardíaco e a atividade adrenal de ratos. Métodos: A indução de Hi em ratos Wistar através de injeções de T3 (150 μg/kg) por 10 dias (grupo com hipertireoidismo - GH) ou veículo (grupo controle). O desempenho cardiovascular foi avaliado por: ecocardiograma (ECO); razão peso do coração/peso corporal (mg/gr); contratilidade de músculos papilares isolados (MPI) e mensuração direta da pressão arterial. A atividade adrenal foi avaliada pela razão peso adrenal/ peso corporal (mg/gr) e níveis de 24 horas de corticosterona fecal (CF) no 1º, 5º e 10º dias de tratamento com T3. Resultados: No GH, o ECO mostrou redução dos Volumes Finais Sistólico e Diastólico, Tempos de Ejeção, Relaxamento Isovolumétrico e Diastólico Total, Áreas Sistólicas e Diastólica e razão E/A. Aumentaram a frequência cardíaca, a fração de ejeção e o débito cardíaco. A razão peso corporal/peso do coração foi maior. Da mesma forma, nos MPI, a taxa máxima de degradação da força durante o relaxamento foi maior em todas as concentrações extracelulares de cálcio. Os níveis de pressão arterial sistólica (PAS) foram maiores. (p ≤ 0,05). Por outro lado, não houve diferença na razão peso das adrenais/peso corporal ou níveis de 24 horas de CF. ...
Background: Hyperthyroidism (Hy) exerts a broad range of influences on a variety of physiological parameters. Its disruptive effect on cardiovascular system is one of its most remarkable impacts. Moreover, Hy has been clinically associated with stress - induced hyperactivation of the hypothalamic-pituitary-adrenal axis. Objective: Evaluate the impact of short-term Hy on cardiac performance and adrenal activity of rats. Methods: Induction of Hy in Wistar rats through injections of T3 (150 µg/kg) for 10 days (hyperthyroid group - HG) or vehicle (control group). The cardiovascular performance was evaluated by: echocardiography (ECHO); heart weight/body weight (mg/gr) ratio; contractility of isolated papillary muscles (IPM) and direct measurement of blood pressures. Adrenal activity was evaluated by adrenal weight/body weight (mg/gr) ratio and 24-hour fecal corticosterone (FC) levels on the, 5th and 10th days of T3 treatment. Results: In HG, the ECHO showed reduction of the End Systolic and End Diastolic Volumes, Ejection, Total Diastolic and Isovolumic Relaxation Times, Diastolic and Systolic Areas and E/A ratio. Heart Rate, Ejection Fraction and Cardiac Output increased. The heart weight/body weight ratio was higher. Similarly, in IPM, the maximum rate of force decay during relaxation was higher in all extracellular calcium concentrations. Systolic blood pressure (SBP) levels were higher. (p ≤ 0.05). On the other hand, there was no difference in the adrenal weight/body weight ratio or in the 24-hour FC levels. Conclusions: Hy induces positive inotropic, chronotropic and lusitropic effects on the heart by direct effects of T3 and increases SBP. Those alterations are not correlated with changes in the adrenal activity. .
Assuntos
Animais , Masculino , Glândulas Suprarrenais/fisiopatologia , Coração/fisiopatologia , Hipertireoidismo/complicações , Hipertireoidismo/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Pressão Sanguínea/fisiologia , Corticosterona/análise , Modelos Animais de Doenças , Ecocardiografia , Frequência Cardíaca/fisiologia , Músculos Papilares/fisiopatologia , Ratos Wistar , Valores de Referência , Fatores de Tempo , Tiroxina/análise , Tri-Iodotironina/análiseRESUMO
BACKGROUND: This study evaluates the effects of probiotic therapy (PT) in rats with ligature-induced periodontitis associated with restraint stress. METHODS: Sixty-four rats were divided into control, stress (STR), probiotic (PROB), periodontal disease (PD), STR-PROB, STR-PD, STR-PROB-PD, and PROB-PD groups. The probiotic was added to the drinking water for 44 days. PD was induced by a ligature. In STR groups, the animals were subjected to restraint stress for 2.5 hours per day for 30 days. RESULTS: Rats with PD exhibited increased alveolar bone loss (P <0.05), as well as increased levels of cyclooxygenase-2, serum C-terminal telopeptide (CTX), p38 mitogen-activated protein kinase (p38), and receptor activator of nuclear factor-κB ligand and decreased levels of osteoprotegerin (OPG). Stressed rats presented high levels of C-peptide, corticosterone, and glucose (P <0.05). In general, the presence of stress reduced the expression of CTX and p38 (P <0.05). PT reduced alveolar bone loss in unstressed animals. It also decreased expression of CTX and induced increased expression of OPG in unstressed animals with PD. However, PT was not effective in preventing bone loss or altering the expression of inflammatory markers in stressed animals. PT decreased the number of inflammatory cells in the periodontal tissue (P <0.05). Groups with stress and PD showed decreased villous height and crypt depth. Stress seemed to prevent part of the probiotic beneficial effects on the small intestine. CONCLUSIONS: Based on the methodology used, PT may reduce tissue breakdown resulting from PD in unstressed rats. The protocol used for restraint stress influenced the immunomodulatory effects of PT in intestinal and periodontal tissues.
Assuntos
Periodontite/terapia , Probióticos/uso terapêutico , Estresse Fisiológico/imunologia , Estresse Psicológico/complicações , Perda do Osso Alveolar/imunologia , Perda do Osso Alveolar/metabolismo , Animais , Glicemia/análise , Peptídeo C/análise , Colágeno Tipo I/sangue , Corticosterona/análise , Ciclo-Oxigenase 2/análise , Gengivite/imunologia , Gengivite/metabolismo , Gengivite/terapia , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Masculino , Osteoprotegerina/análise , Peptídeos/sangue , Periodontite/imunologia , Periodontite/metabolismo , Ligante RANK/análise , Ratos , Ratos Wistar , Estresse Psicológico/imunologia , Estresse Psicológico/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/análiseRESUMO
The objectives of the present study were to evaluate fecal concentrations of metabolites of glucocorticoids, measured by enzyme immunoassay with a cortisol antibody and by radioimmunoassay with a corticosterone antibody, and progesterone by radioimmunoassay with a progesterone antibody in blue-fronted parrot (Amazona aestiva) after ACTH challenge. The adrenal stimulation with ACTH (25 UI/animal) resulted in an increase of fecal glucocorticoids metabolites concentration, but it did not affect the concentrations of fecal progesterone metabolites. Although there were no synchronized peaks of glucocorticoid metabolites excretion measured by enzyme immunoassay and radioimmunoassay, there were two peaks of excretion, one at 2-4 hours and other at 8-10 hours. Despite the occurrence of peaks, the analysis of fecal glucocorticoids metabolites and progesterone metabolites showed no effect of group (control and treatment), moment (hours of sampling) and sex.
Os objetivos do presente trabalho foram avaliar as concentrações fecais de metabólitos de glicocorticoides, mensurados por enzimaimunoensaio, empregando-se anticorpos contra cortisol, e por radioimunoensaio, empregando-se anticorpo contra corticosterona, e dos metabólitos da progesterona, mensurados por raioimunoensaio empregando-se anticorpo contra progesterona, em papagaios-verdadeiros (Amazona aestiva) após desafio com ACTH. A estimulação da adrenal com 25 UI/animal de ACTH resultou na elevação das concentrações de metabólitos de glicocorticoides, mas não modificou a dos metabólitos da progesterona fecal em papagaio-verdadeiro. Embora não tenha sido observada a sincronização dos picos de excreção fecal dos metabólitos de glicocorticoides mensurados por enzimaimunoensaio e radioimunoensaio, houve dois picos de excreção, um entre 2 e 4 horas e outro entre 8 e 10 horas. Apesar dos picos, não foram detectados efeitos de Grupos (Tratamento x Controle), momento (horas de coleta) ou sexo (macho x fêmea) nos resultados observados nas concentrações fecais de metabólitos de glicocorticoides e de progesterona, com os métodos empregados.
Assuntos
Animais , Aves/metabolismo , Biomarcadores Tumorais/análise , Corticosterona/análise , Glucocorticoides/análise , Hidrocortisona/análise , Papagaios/metabolismo , Progesterona/análise , Fezes , Imunoensaio/métodosRESUMO
The objectives of the present study were to evaluate fecal concentrations of metabolites of glucocorticoids, measured by enzyme immunoassay with a cortisol antibody and by radioimmunoassay with a corticosterone antibody, and progesterone by radioimmunoassay with a progesterone antibody in blue-fronted parrot (Amazona aestiva) after ACTH challenge. The adrenal stimulation with ACTH (25 UI/animal) resulted in an increase of fecal glucocorticoids metabolites concentration, but it did not affect the concentrations of fecal progesterone metabolites. Although there were no synchronized peaks of glucocorticoid metabolites excretion measured by enzyme immunoassay and radioimmunoassay, there were two peaks of excretion, one at 2-4 hours and other at 8-10 hours. Despite the occurrence of peaks, the analysis of fecal glucocorticoids metabolites and progesterone metabolites showed no effect of group (control and treatment), moment (hours of sampling) and sex. (AU)
Os objetivos do presente trabalho foram avaliar as concentrações fecais de metabólitos de glicocorticoides, mensurados por enzimaimunoensaio, empregando-se anticorpos contra cortisol, e por radioimunoensaio, empregando-se anticorpo contra corticosterona, e dos metabólitos da progesterona, mensurados por raioimunoensaio empregando-se anticorpo contra progesterona, em papagaios-verdadeiros (Amazona aestiva) após desafio com ACTH. A estimulação da adrenal com 25 UI/animal de ACTH resultou na elevação das concentrações de metabólitos de glicocorticoides, mas não modificou a dos metabólitos da progesterona fecal em papagaio-verdadeiro. Embora não tenha sido observada a sincronização dos picos de excreção fecal dos metabólitos de glicocorticoides mensurados por enzimaimunoensaio e radioimunoensaio, houve dois picos de excreção, um entre 2 e 4 horas e outro entre 8 e 10 horas. Apesar dos picos, não foram detectados efeitos de Grupos (Tratamento x Controle), momento (horas de coleta) ou sexo (macho x fêmea) nos resultados observados nas concentrações fecais de metabólitos de glicocorticoides e de progesterona, com os métodos empregados.(AU)
Assuntos
Animais , Aves/metabolismo , Papagaios/metabolismo , Biomarcadores Tumorais/análise , Glucocorticoides/análise , Progesterona/análise , Corticosterona/análise , Hidrocortisona/análise , Fezes , Imunoensaio/métodosRESUMO
Os camundongos utilizados em biotérios pertencem à família Muridae, subfamília Murinae, ordem Rodentia, gênero Mus e espécie Mus musculus. São animais sociais e territoriais. Diversas linhagens foram desenvolvidas em laboratório porém apresentam comportamento agressivo semelhante ao de camundongos selvagens. O objetivo deste estudo foi caracterizar a estrutura hierárquica, características corporais e os níveis de hormônios em camundongos dominantes, subordinadas e não-agressivos. O modelo de avaliação do padrão de comportamento agressivo (PCA) classificou os animais da seguinte forma: LAg - indivíduos com comportamento agressivo baixo, HAg - dominante (altamente agressivo) e Sb - subordinado. O reagrupamento de camundongos macho adulto promove um efeito estressor considerável e influencia a formação de sua estrutura hierárquica. Comparações comportamentais antes (BfR) e após reagrupamento mostrou que o percentual de peso perdido por animais nas categorias especificadas foram as seguintes: Lag - 68,1% , HAg - 86,9% e Sb - 90,5% ; os níveis médios de corticosterona por categoria foram BfR : 43,5 ± 17,5, LAg: 177,0 ± 40,4, Hag: 72,8±23,8 e Sb: 136,4±51,2 ng/mL. Camundongos dominantes apresentaram diferenças nas características do corpo (principalmente a relação corpo/ cauda) em relação aos indivíduos subordinados. Também foram observadas duas posições hierárquicas adicionais: indivíduo neutro (sem comportamento agressivo) e subordinado alvo. (AU)
The mice used in animal facilities belong to the family Muridae, subfamily Murinae, order Rodentia, genus Mus and species Mus musculus. They are social and territorial animals. Several lineages developed in the laboratory show aggressive behavior similar to that of wild mice. The aim of this study was characterize the hierarchical structure, body characteristics and hormonal levels in dominant, subordinate and non-aggressive mice. The model established for spontaneous aggression (MSA) evaluates the pattern of aggressive behavior (PBA) and categorizes the animals as follows: LAg - individuals with low aggressive behavior, HAg dominant (highly aggressive) and Sb - subordinate. The regrouping of adult male mice produces substantial stress and influences the formation of their hierarchical structure. Behavioral comparisons before regrouping (BfR) and after regrouping showed that the percentage of body weight lost in mice was dependent of the specific categories as follows: LAg - 68.1%, HAg - 86.9% and Sb - 90.5%; the average corticosterone levels by category were BfR: 43.5±17.5, LAg: 177.0±40.4, HAg: 72.8±23.8 and Sb: 136.4±51.2 ng/mL. Dominant mice showed differences in body characteristics (primarily the body/tail relationship) relative to subordinate mice. Two additional hierarchical positions were observed: neutral individual (without aggressive behavior) and subordinate target (an animal that receives approximately 30% of the total number of attacks made by dominant animals). (AU)
Assuntos
Animais , Ratos , Muridae/classificação , Comportamento Animal , Hierarquia Social , Camundongos , Corticosterona/análise , Modelos AnimaisRESUMO
Os camundongos utilizados em biotérios pertencem à família Muridae, subfamília Murinae, ordem Rodentia, gênero Mus e espécie Mus musculus. São animais sociais e territoriais. Diversas linhagens foram desenvolvidas em laboratório porém apresentam comportamento agressivo semelhante ao de camundongos selvagens. O objetivo deste estudo foi caracterizar a estrutura hierárquica, características corporais e os níveis de hormônios em camundongos dominantes, subordinadas e não-agressivos. O modelo de avaliação do padrão de comportamento agressivo (PCA) classificou os animais da seguinte forma: LAg - indivíduos com comportamento agressivo baixo, HAg - dominante (altamente agressivo) e Sb - subordinado. O reagrupamento de camundongos macho adulto promove um efeito estressor considerável e influencia a formação de sua estrutura hierárquica. Comparações comportamentais antes (BfR) e após reagrupamento mostrou que o percentual de peso perdido por animais nas categorias especificadas foram as seguintes: Lag - 68,1% , HAg - 86,9% e Sb - 90,5% ; os níveis médios de corticosterona por categoria foram BfR : 43,5 ± 17,5, LAg: 177,0 ± 40,4, Hag: 72,8±23,8 e Sb: 136,4±51,2 ng/mL. Camundongos dominantes apresentaram diferenças nas características do corpo (principalmente a relação corpo/ cauda) em relação aos indivíduos subordinados. Também foram observadas duas posições hierárquicas adicionais: indivíduo neutro (sem comportamento agressivo) e subordinado alvo.
The mice used in animal facilities belong to the family Muridae, subfamily Murinae, order Rodentia, genus Mus and species Mus musculus. They are social and territorial animals. Several lineages developed in the laboratory show aggressive behavior similar to that of wild mice. The aim of this study was characterize the hierarchical structure, body characteristics and hormonal levels in dominant, subordinate and non-aggressive mice. The model established for spontaneous aggression (MSA) evaluates the pattern of aggressive behavior (PBA) and categorizes the animals as follows: LAg - individuals with low aggressive behavior, HAg dominant (highly aggressive) and Sb - subordinate. The regrouping of adult male mice produces substantial stress and influences the formation of their hierarchical structure. Behavioral comparisons before regrouping (BfR) and after regrouping showed that the percentage of body weight lost in mice was dependent of the specific categories as follows: LAg - 68.1%, HAg - 86.9% and Sb - 90.5%; the average corticosterone levels by category were BfR: 43.5±17.5, LAg: 177.0±40.4, HAg: 72.8±23.8 and Sb: 136.4±51.2 ng/mL. Dominant mice showed differences in body characteristics (primarily the body/tail relationship) relative to subordinate mice. Two additional hierarchical positions were observed: neutral individual (without aggressive behavior) and subordinate target (an animal that receives approximately 30% of the total number of attacks made by dominant animals).
Assuntos
Animais , Ratos , Comportamento Animal , Hierarquia Social , Muridae/classificação , Camundongos , Corticosterona/análise , Modelos AnimaisRESUMO
The intensification of animal production systems presents a potential impact on the welfare of animals. The objective of this work was to assess the welfare of quail Coturnixcoturnix japonicain two maintenance systems: battery cages (BC),and enriched aviary (EA),with saw-dust bedding, sand-bathing area and nests. The experiment procedure involved eight animals per holding area and four repetitions per treatment, an overall of 64 quails. Welfare was assessed through behavioral freedom, sanitary freedom (feather condition and injuries), blood analyses and glicocorticoid metabolites measurement in droppings. Results are presented in the BC order, followed by EA. Water drinking behavior and agonistic behavior were different between treatments (P<0.05). Feather condition was adequate in both treatments, except for the head in BC quails. Blood data were statistically different forred blood cells, hematocrit, hemoglobin, blood proteins, eosinophils, heterophils, lymphocytes and heterophil: lymphocyte ratio. Glicocorticoid metabolites levels were significantly different between maintenance systems. The behavioral and physiological welfare indicators showed higher welfare degree for quails in enriched aviary as compared to battery cages system.
O objetivo deste trabalho foi avaliar o bem-estar de codornas (Coturnix coturnix japonica) em dois sistemas de manutenção: gaiolas industriais em baterias (BC) e aviários enriquecidos (EA) com cama de serragem, caixa de areia e ninhos. O procedimento experimental envolveu oito animais por área experimental equatrorepetiçõesportratamento, totalizando64codornas. O bem-estar animal foi avaliado por meio da liberdade comportamental e da liberdade sanitária -condição das penas e ferimentos -, análises de sangue e mensuração de glicocorticoides nas fezes. Atividade de beber água e comportamento agonístico foram diferentes entre os tratamentos (P<0,05). A condição das penas foi adequada em ambos os tratamentos, exceto para a condição das cabeças em codornas do tratamento BC. Os dados do sangue foram diferentes para eritrócitos, hematócrito, hemoglobina, proteínas sanguíneas, eosinófilos, heterófilos e linfócitos e para a relação heterófilo:linfócito. Os níveis de metabólitos glicocorticoides foram significativamente diferentes entre os sistemas de manutenção. Os indicadores comportamentais e fisiológicos de bem-estar mostraramalto grau de bem-estar para as codornas no EA em relação às no BC.