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1.
Artigo em Inglês | MEDLINE | ID: mdl-33772638

RESUMO

The dopaminergic system of zebrafish is complex and the numerous pathways and receptors in the central nervous system (CNS) are being extensively studied. A critical factor for the synthesis, activation and release of catecholamines (CAs) is the presence of tyrosine hydroxylase, an enzyme which converts L-tyrosine into levodopa. Levodopa thus is the intermediary in the synthesis of dopamine (DA) and norepinephrine (NE) and promotes its release; therefore, CAs play an important role in the CNS with hormonal functions. Here, we use levodopa/carbidopa to clarify the involvement of the dopaminergic pathway in the stress response in zebrafish submitted to an acute stress challenge. Acute stress was induced by chasing fish with a net for 2 min and assessed by measuring whole-body cortisol levels. Two experiments were carried out, the first with exposure to levodopa/carbidopa and the second with exposure to AMPT and levodopa/carbidopa. Levodopa/carbidopa balances the stress response through its action on the zebrafish hypothalamic-pituitary-adrenal (HPA) axis. Changes in cortisol levels suggest that DA was related to the balance of the stress response and that NE decreased this response. These effects were specific to stress since levodopa/carbidopa did not induce changes in cortisol in non-stressed fish.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32800866

RESUMO

Methylphenidate (MPH) is a psychostimulant widely misused to increase wakefulness by drivers and students. Also, MPH can be found in dietary supplements in a clandestine manner aiming to burst performance of physical exercise practitioners. The abusive use of high doses of caffeine (CAF) in these contexts is equally already known. Here, we demonstrate the behavioral, oxidative and mitochondrial effects after acute exposure to high doses of MPH (80 mg/L) and CAF (150 mg/L), alone or associated (80 mg/L + 150 mg/L, respectively). We used zebrafish as animal model due to its high translational relevance. We evaluated the behavioral effects using the Novel Tank Test (NTT), Social Preference Test (SPT) and Y-maze Task and analyzed biomarkers of oxidative stress and activity of mitochondrial respiratory chain complexes. MPH alone induced antisocial behavior. MPH inhibited lipid peroxidation. The association of MPH + CAF presented memory impairment and anxiogenic behavior. In oxidative status, it inhibited lipid peroxidation, increased protein carbonylation and mitochondrial complex II, III and IV activity. Our results demonstrate that MPH and CAF alone negatively impact the typical behavioral of zebrafish. When associated, changes in cognition, memory, oxidative and mitochondrial status are more relevant.

3.
Pharmacol Biochem Behav ; 189: 172841, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31893526

RESUMO

Environmental pollution caused by antipsychotic residues is a relevant ecological problem. Studies revealed that residues of these drugs are present in a wide range of different ecosystems and can have adverse effects on non-target organisms even in low environmental concentrations. Among these antipsychotic drugs, aripiprazole (APPZ) is a second-generation atypical antipsychotic that is a partial agonist of dopaminergic and serotoninergic receptors. APPZ is used to treat schizophrenia, bipolar disorder, autism, obsessive-compulsive disorder, and anxiety or panic disorders. Thus, in this study we posed the following question: "What will be the behavioral effects of waterborne APPZ on fish?" To answer this question, we exposed adult zebrafish to different APPZ concentrations (0.556, 5.56, and 556 ng/L) for 15 min and evaluated their exploratory, anxiety-like, social, and anti-predatory behaviors. Our results showed that, despite the apparent beneficial reversal of stress-induced social impairment and anxiety-like behavior, APPZ exposure impaired the anti-predatory reaction of adult zebrafish. Taken altogether, our results show that APPZ-exposed zebrafish may have a decreased perception of predators, even at concentrations lower than those already detected in the environment. A failure to exhibit an antipredatory response may favor the predator, decrease the fitness of the prey species, and, consequently, affect the food chain. Our results highlight the risks and consequences associated with APPZ residues in water, which may affect aquatic life and endanger species that depend on appropriate behavioral responses for survival.

4.
Environ Sci Pollut Res Int ; 26(25): 26293-26303, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286368

RESUMO

Since behavior is the connection between the internal physiological processes of an animal and its interaction with the environment, a complete behavioral repertoire is crucial for fish survival and fitness, at both the individual and population levels. Thus, unintended exposure of non-target organisms to antipsychotic residues in the environment can impact their normal behavior, and some of these behavioral changes can be seen during the entire life of the animal and passed to subsequent generations. Although there are some reports related to transgenerational toxicology, little is known of the long-term consequences of exposure to pharmaceutical compounds such as risperidone. Here, we show that zebrafish exposed to risperidone (RISP) during embryonic and larval stages presented impaired anti-predatory behavior during adulthood, characterizing a persistent effect. We also show that some of these behavioral changes are present in the following generation, characterizing a transgenerational effect. This suggests that even short exposures to environmentally relevant concentrations, at essential stages of development, can persist throughout the whole life of the zebrafish, including its offspring. From an environmental perspective, our results suggested possible risks and long-term consequences associated with drug residues in water, which can affect aquatic life and endanger species that depend on appropriate behavioral responses for survival.


Assuntos
Risperidona/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Comportamento Animal/efeitos dos fármacos , Ecotoxicologia/métodos , Embrião não Mamífero/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Masculino , Comportamento Predatório/efeitos dos fármacos , Peixe-Zebra/embriologia , Peixe-Zebra/fisiologia
5.
Arch Environ Contam Toxicol ; 77(3): 443-451, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31190101

RESUMO

Environmental contamination caused by the human occupancy and economic activities that generate a wide range of contaminated effluents that reach natural water resources, is a current reality. Residues of agrichemicals used in plant production were detected in different environments and in different countries. Among these agrochemicals, we studied a glyphosate-based herbicide (GBH), a fipronil-based insecticide (FBI), and their mixtures (GBH + FBI). Zebrafish exposed to 3 and 5 mg/L of GBH spend more time in the top zone and less time in the bottom zone. Fish exposed to 0.009 and 0.018 mg/L of FBI spent less time in the bottom zone, whereas zebrafish exposed to the three GBH + FBI mixtures spend more time in the top zone compared with unexposed control fish. This clear anxiolytic pattern, in an environmental context, can directly impair the ability of fish to avoid or evade predators. We concluded that both glyphosate-based herbicide and fipronil-based insecticide and their mixtures alter zebrafish behavior, which may result in significant repercussions on the maintenance of the species as well as on the food chain and the ecosystem.


Assuntos
Glicina/análogos & derivados , Praguicidas/toxicidade , Pirazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Ecossistema , Feminino , Glicina/toxicidade , Humanos , Masculino , Comportamento Predatório
6.
Sci Rep ; 8(1): 13908, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30224742

RESUMO

Here we show that the novel object recognition test can discriminate between high (HRN, neophobic) and low (LRN, neophilic) novelty responders in zebrafish populations. Especially when we observe the latency to the first entry in the novel object zone, zebrafish did not maintain these behavioral phenotypes in sequential tests and only the HRN group returned to their initial responsive behavior when exposed to fluoxetine. Our results have important implications for behavioral data analysis since such behavioral differences can potentially increase individual response variability and interfere with the outcomes obtained from various behavioral tasks. Our data reinforce the validity of personality determination in zebrafish since we show clear differences in behavior in response to fluoxetine.


Assuntos
Comportamento Animal/efeitos dos fármacos , Fluoxetina/farmacologia , Peixe-Zebra/fisiologia , Animais , Masculino
7.
Sci Rep ; 7(1): 14121, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074994

RESUMO

The ability to avoid and escape from predators are clearly relevant behaviors from the ecological perspective and directly interfere with the survival of organisms. Detected in the aquatic environment, risperidone can alter the behavior of exposed species. Considering the risk of exposure in the early stages of life, we exposed zebrafish embryos to risperidone during the first 5 days of life. Risperidone caused hyperactivity in exposed larvae, which in an environmental context, the animals may be more vulnerable to predation due to greater visibility or less perception of risk areas.


Assuntos
Comportamento Animal/efeitos dos fármacos , Resíduos de Drogas/farmacologia , Larva/efeitos dos fármacos , Psicotrópicos/farmacologia , Risperidona/farmacologia , Poluentes Químicos da Água/farmacologia , Peixe-Zebra , Animais , Relação Dose-Resposta a Droga
8.
Gen Comp Endocrinol ; 252: 236-238, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28716505

RESUMO

In this article, we show that the tyrosine hydroxylase inhibitor α-Methyl-l-tyrosine (AMPT) decreased the responsiveness of the zebrafish stress axis to an acute stressful challenge. These effects were specific for responses to stimulation, since unstimulated (basal) cortisol levels were not altered by AMPT. Moreover, AMPT decreased the stress response 15min after stimulation, but not after that time period. To our knowledge, this is the first report about the effects of AMPT on the neuroendocrine axis of adult zebrafish in acute stress responses. Overall, these results suggest a mechanism of catecholamine-glucocorticoid interplay in neuroendocrine responses of fish, pointing an interesting avenue for physiological research, as well as an important endpoint that can be disrupted by environmental contamination. Further experiments will unravel the mechanisms by which AMPT blocked the cortisol response.


Assuntos
Inibidores Enzimáticos/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/antagonistas & inibidores , Peixe-Zebra/fisiologia , alfa-Metiltirosina/farmacologia , Animais , Feminino , Hidrocortisona/sangue , Masculino , Tirosina 3-Mono-Oxigenase/metabolismo , Peixe-Zebra/sangue
9.
Environ Toxicol ; 32(7): 1964-1972, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28371364

RESUMO

The glucocorticoid cortisol, the end product of hypothalamus-pituitary-interrenal axis in zebrafish (Danio rerio), is synthesized via steroidogenesis and promotes important physiological regulations in response to a stressor. The failure of this axis leads to inability to cope with environmental challenges preventing adaptive processes in order to restore homeostasis. Pesticides and agrichemicals are widely used, and may constitute an important class of environmental pollutants when reach aquatic ecosystems and nontarget species. These chemical compounds may disrupt hypothalamus-pituitary-interrenal axis by altering synthesis, structure or function of its constituents. We present evidence that organophosphorus exposure disrupts stress response by altering the expression of key genes of the neural steroidogenesis, causing downregulation of star, hsp70, and pomc genes. This appears to be mediated via muscarinic receptors, since the muscarinic antagonist scopolamine blocked these effects.


Assuntos
Disruptores Endócrinos/toxicidade , Inseticidas/toxicidade , Metil Paration/toxicidade , Receptores Muscarínicos/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Proteínas de Choque Térmico HSP72/genética , Proteínas de Choque Térmico HSP72/metabolismo , Hidrocortisona/metabolismo , Locomoção/efeitos dos fármacos , Antagonistas Muscarínicos/farmacologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Pró-Opiomelanocortina/genética , Pró-Opiomelanocortina/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/metabolismo , Escopolamina/farmacologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
Neurosci Lett ; 650: 114-117, 2017 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-28445770

RESUMO

Several studies have reported the presence of methylphenidate (MPH) in effluents; however, its impacts on aquatic life are not yet well understood. Here, we investigated the effects of acute exposure on endocrine and behavioral stress responses to environmentally relevant concentrations of MPH in zebrafish. We show that MPH blunts the response of cortisol to stress in zebrafish. On the other hand, MPH stresses fish per se. Additionally, MPH seems to modulate anxiety-like behaviors. We conclude that the presence of MPH in aquatic environments can alter neuroendocrine and behavior responses, which might considerably impact fish survival and welfare.


Assuntos
Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Hidrocortisona/metabolismo , Metilfenidato/administração & dosagem , Estresse Fisiológico/efeitos dos fármacos , Poluentes Químicos da Água/administração & dosagem , Peixe-Zebra/fisiologia , Animais , Estimulantes do Sistema Nervoso Central/administração & dosagem , Relação Dose-Resposta a Droga , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/fisiologia , Feminino , Humanos , Estresse Fisiológico/fisiologia
11.
Zebrafish ; 14(1): 51-59, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27672711

RESUMO

In this study, we show that an adaptation of the spinning test can be used as a model to study the exercise-exhaustion-recovery paradigm in fish. This forced swimming test promotes a wide range of changes in the hypothalamus-pituitary-interrenal axis functioning, intermediary metabolism, as well in fish behavior at both exercise and recovery periods. Our results pointed that this adapted spinning test can be considered a valuable tool for evaluating drugs and contaminant effects on exercised fish. This can be a suitable protocol both to environmental-to evaluate contaminants that act in fish energy mobilization and recovery after stressors-and translational perspectives-effects of drugs on exercised or stressed humans.


Assuntos
Glucose/análise , Hidrocortisona/análise , Condicionamento Físico Animal/métodos , Natação , Peixe-Zebra/fisiologia , Animais , Comportamento Animal , Creatina Quinase/análise , Metabolismo Energético , Modelos Animais , Estresse Fisiológico , Peixe-Zebra/sangue
12.
Sci Rep ; 6: 37612, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27874070

RESUMO

Here we provide, at least to our knowledge, the first evidence that aripiprazole (APPZ) in the water blunts the stress response of exposed fish in a concentration ten times lower than the concentration detected in the environment. Although the mechanism of APPZ in the neuroendocrine axis is not yet determined, our results highlight that the presence of APPZ residues in the environment may interfere with the stress responses in fish. Since an adequate stress response is crucial to restore fish homeostasis after stressors, fish with impaired stress response may have trouble to cope with natural and/or imposed stressors with consequences to their welfare and survival.


Assuntos
Aripiprazol/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Feminino , Hidrocortisona/metabolismo , Masculino
13.
Arch Environ Contam Toxicol ; 71(3): 415-22, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27423874

RESUMO

In agriculture intensive areas, fishponds and natural water bodies located in close proximity to these fields receive water with variable amounts of agrichemicals. Consequently, toxic compounds reach nontarget organisms. For instance, aquatic organisms can be exposed to tebuconazole-based fungicides (TBF), glyphosate-based herbicides (GBH), and atrazine-based herbicides (ABH) that are potentially dangerous, which motivates the following question: Are these agrichemicals attractant or aversive to fish? To answer this question, adult zebrafish were tested in a chamber that allows fish to escape from or seek a lane of contaminated water. This attraction and aversion paradigm was evaluated with zebrafish in the presence of an acute contamination with these compounds. We showed that only GBH was aversive to fish, whereas ABH and TBF caused neither attraction nor aversion for zebrafish. Thus, these chemicals do not impose an extra toxic risk by being an attractant for fish, although TBF and ABH can be more deleterious, because they induce no aversive response. Because the uptake and bioaccumulation of chemicals in fish seems to be time- and dose-dependent, a fish that remains longer in the presence of these substances tends to absorb higher concentrations than one that escapes from contaminated sites.


Assuntos
Agroquímicos/toxicidade , Peixes/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Aprendizagem da Esquiva , Comportamento Animal , Testes de Toxicidade , Peixe-Zebra
14.
PLoS One ; 10(10): e0140800, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26473477

RESUMO

The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but its impacts on aquatic organisms are not yet well understood. This study investigated the effects of acute exposure to the antipsychotic risperidone on the stress and behavioral responses in zebrafish. It became clear that intermediate concentration of risperidone inhibited the hypothalamic-pituitary-interrenal axis and displayed anxiolytic-like effects in zebrafish. The data presented here suggest that the presence of this antipsychotic in aquatic environments can alter neuroendocrine and behavior profiles in zebrafish.


Assuntos
Ansiolíticos/efeitos adversos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Risperidona/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Peixe-Zebra/metabolismo , Animais , Ansiolíticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/patologia , Sistema Hipófise-Suprarrenal/patologia , Risperidona/farmacologia , Poluentes Químicos da Água/farmacologia
15.
Ciênc. rural ; 38(3): 723-728, maio-jun. 2008. tab
Artigo em Português | LILACS | ID: lil-480184

RESUMO

Com o objetivo de se avaliarem os resultados do uso de endoscopia rígida e da técnica por tubo endotraqueal de colheita de líquido traqueobrônquico, foram utilizados 28 cães, errantes ou domiciliados, distribuídos em dois grupos. Nos cães do grupo 1, aplicou-se a técnica de lavado traqueobrônquico em 14 cães, sendo sete sadios e sete com sinais clínicos respiratórios. Nos do grupo 2, utilizou-se a mesma técnica, entretanto com endoscopia rígida, em sete cães sadios e em sete cães com sinais clínicos de doença respiratória. Os dados evidenciaram que o procedimento utilizando-se endoscópio rígido resultou em menor volume de solução infundida e em maior porcentagem de solução recuperada. Não houve diferença significativa quanto ao tempo de duração da execução da técnica. A contagem bacteriana foi mais alta nas amostras coletadas por endoscópio rígido, porém não houve diferença significativa na contagem de células nucleadas totais. Portanto, o uso da endoscopia rígida para colheita de líquido traqueobrônquico mostrou-se mais vantajosa do que a técnica convencional utilizando-se o tubo endotraqueal, pois fornece imagens das vias aéreas e permite acompanhamento visual da lavagem.


The present study aimed to evaluate the results of rigid endoscopy and endotracheal tube techniques for collecting tracheobronchic fluid from dogs. Twenty eight erratic or housed dogs, were allocated into to two groups. In group 1, tracheobronchic washing was applied to seven healthy dogs and seven dogs with clinical signs of respiratory disease. In group 2, seven healthy and seven dogs with respiratory disease were submitted to endo-bronchial washing by rigid endoscopy. Using rigid endoscopy, a lower volume was introduced but a higher percentage of washing fluid was recovered. There was no difference regarding the time necessary to perform both techniques. Bacterial counts were higher in samples collected by rigid endoscopy, but there was no difference in total nucleated cell counts from these samples. Thus, the use of rigid endoscopy to collect tracheobronchic fluid was found to be advantageous when compared to the conventional technique using endotracheal tube.


Assuntos
Animais , Cães , Endoscópios/veterinária , Herpesvirus Canídeo 1 , Intubação Intratraqueal/veterinária
16.
Braz. j. vet. res. anim. sci ; 37(5): 382-387, 2000. ilus, graf
Artigo em Português | LILACS | ID: lil-327435

RESUMO

Três vias de fornecimento de dietas pós-operatórias foram comparadas na cicatrizaçäo de esofagostomia cervical. Foram utilizados 15 cäes, divididos em três grupos (GI, GII e GIII). No GI foi procedida à fluidoterapia durante 48 horas, alimento líquido durante mais 48 horas e pastoso por 72 horas (dieta tradicional), no GII o alimento foi fornecido por sonda faringogástrica, colocada por faringostomia, e no GIII por sonda gástrica, implantada por gastrostomia endoscópica percutânea. Para avaliar a cicatrizaçäo, foram realizados exame clínico diário e esofagoscopias semanais, durante seis semanas. A endoscopia perceberam-se algumas ocorrências indesejáveis que retardam a cicatrizaçäo da mucosa esofágica: edema entre os pontos na primeira endoscopia pós-operatória (GI) e ulceraçöes na mucosa esofágica pelo atrito da sonda faringogástrica sobre a cicatriz (GII). A alimentaçäo por sonda gástrica resultou em menor tempo de cicatrizaçäo (1,40 ñ 0,55 semanas, p < 0,01), em comparaçäo aos alimentados por sonda faringogástrica (4,25 ñ 1,50 semanas). No GIII as características clínicas da cicatrizaçäo foram de melhor qualidade, provavelmente devido à ausência de movimentos de deglutiçäo e de atrito do bolo alimentar sobre a ferida cirúrgica. Com base nos resultados, recomenda-se o uso de nutriçäo enteral por sonda gástrica colocada por gastrostomia endoscópica percutânea, durante os primeiros sete dias de pós-operatório, e, na ausência de um endoscópio, a dieta tradicional, que resulta em cicatrizaçäo de melhor qualidade do que o uso de sonda por faringostomia


Assuntos
Animais , Feminino , Esofagostomia , Gastrostomia , Faringostomia , Período Pós-Operatório
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