RESUMO
1. Ross × Ross 308 male broilers were used to study the impact of 14, 17, 20 and 23 h of light (L) on flock behavioural patterns and 24 h melatonin rhythm synchrony during the photophase. 2. Behaviour in two pens (n = 53) per lighting treatment was digitally recorded for 24 h in trial 1 (27-28 d of age (d 27)) and two (42-43 d (d 42)), and quantified using a scan sampling technique at 10 min intervals. Regression procedures were used to test flock trend analysis between behavioural (resting, standing, walking and feeding) variables and time during the photophase. 3. The presence of a flock melatonin rhythm was determined by radioimmunoassay of blood samples collected at 6 times for birds raised on 23L and 8 times for 14, 17 and 20L birds (n = 6 per time) over a 24 h period (d 21) in experiment 1. 4. Quadratic and linear relationships between time and behaviour during the photophase were frequent in 14L and 17L birds, sporadic in 20L birds and non-existent in 23L birds. Relationships were noted in inactive resting (d 27: 14L and 17L; d 42: 14L and 20L), walking (d 27: 14L and 17L), standing (d 27 and d 42: 14L, 17L and 20L) and feeding (d 27: 14L and 17L). A quadratic time × melatonin relationship existed in 14L, 17L and 20L flocks only. 5. Behaviour during the photophase and 24 h melatonin production indicates that flocks exposed to 23L do not develop synchronised rhythms, increasing the risk of suffering from sleep fragmentation.
Assuntos
Criação de Animais Domésticos , Comportamento Animal/efeitos da radiação , Galinhas/fisiologia , Melatonina/sangue , Atividade Motora , Fotoperíodo , Bem-Estar do Animal , Animais , Comportamento de Ingestão de Líquido/efeitos da radiação , Comportamento Alimentar/efeitos da radiação , Locomoção/efeitos da radiação , Masculino , Distribuição AleatóriaRESUMO
Introduction Traumatic experiences and disordered sleep are strongly associated with drinking problems. We examined the effects of experiencing the Great East Japan Earthquake and subsequent nuclear power plant accident, and of sleep problems, on behavioral changes observed in non-drinkers.Methods This study examined cross-sectional data from the Mental Health and Lifestyle Survey conducted among residents in restricted areas of Fukushima in 2012. Participants were 21,454 evacuees aged 20 years or older at the time of disaster. People who did not drink before the disaster but became drinkers afterwards were compared with the rest of the cohort. We analyzed the association between behavioral changes in non-drinkers and potentially predictive variables, using logistic regression.Results The behavioral change of non-drinkers becoming drinkers (n=2,148) was significantly related to being male (OR=1.93, 95% CI:1.74-2.15), being younger (21-49 yrs, OR=1.85, 95% CI: 1.60-2.13), having less educational attainment (up to high school graduate, OR=1.21, 95% CI:1.09-1.35), smoking (OR=1.22, 95% CI:1.08-1.38), losing family or relatives (OR=1.21, 95% CI:1.07-1.37), change in employment (OR=1.19, 95% CI:1.07-1.32), having severe sleep problems as measured by a Japanese version of the Athens Insomnia Scale (3-8, OR=1.45, 95% CI:1.30-1.62), and severity of traumatic symptoms as measured by the PTSD Checklist Stressor-Specific (PCL-S) score (<44, OR=1.33, 95% CI:1.17-1.51).Conclusion Having sleep problems and having more severe traumatic symptoms are significantly related to non-drinkers becoming drinkers.
Assuntos
Comportamento de Ingestão de Líquido/efeitos da radiação , Acidente Nuclear de Fukushima , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto JovemRESUMO
At the organismic level, exposure to radiation can produce taste aversion (CTA) learning and emesis, which have been proposed as behavioral endpoints that are mediated by harmful effects of radiations on peripheral systems, primarily the gastrointestinal system. Thus, the aim of the present investigation was to study the gastroprotective action of hydroalcoholic extract of zingiber rhizome (Zingiber officinale Rosc.) against radiation-induced conditioned taste aversion (CTA) in both male and female species of animals, for testing its potential as a behavioral radioprotector. Administration of zingiber extract 1 h before 2-Gy gamma-radiation was significantly effective in blocking the saccharin avoidance response, with 200 and 250 mg/kg b.wt. i.p., being the most effective doses for male and female rats, respectively. A comparison of the efficacy of zingiber extract with two antiemetic drugs, ondansteron and dexamethasone, revealed that the extract rendered comparable protection against radiation-induced CTA. Our experiments also confirmed the existence of sex dichotomy (i.e., the sex of animal greatly influenced response towards radiation exposure) in relation to behavioral responses (CTA) or differential metabolism. The observed gender variations were hypothesized to be a result of hormonal fluctuations and differences in pharmacological parameters in male and female rats. To correlate the mechanism of action, the free-radical-scavenging potential of zingiber extract to scavenge hydroxyl ion and nitric oxide was also tested, in cell-free system and a concentration of 1000 microg/ml, was found to be the most potent, which has been proposed as one the many activities assisting in its overall ability to modulate radiation-induced taste aversion. The results demonstrate that Z. officinale possesses antioxidant, radioprotective and neuromodulatory properties that can be effectively utilized for behavioral radioprotection and for efficiently mitigating radiation-induced CTA in both males and females species.
Assuntos
Condicionamento Psicológico/efeitos da radiação , Comportamento de Ingestão de Líquido/efeitos da radiação , Paladar/efeitos da radiação , Zingiber officinale , Animais , Antieméticos/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Dexametasona/farmacologia , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Feminino , Sequestradores de Radicais Livres/farmacologia , Raios gama , Masculino , Ondansetron/farmacologia , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Ratos , Ratos Sprague-Dawley , Sacarina , Paladar/efeitos dos fármacos , Irradiação Corporal Total/efeitos adversosRESUMO
The aim of the present study was to investigate the neurobehavioral protective efficacy of a hydroalcoholic extract of ginger (Zingiber officinale Rosc.) in mitigating gamma radiation-induced conditioned taste aversion in Sprague-Dawley rats. Administration of Zingiber extract 1 h before 2-Gy gamma irradiation was effective in blocking the saccharin avoidance response for 5 post-treatment observational days, both in a dose- and time-dependent manner, with 200 mg/kg b.w. i.p. being the most effective dose. Highest saccharin intake in all the groups was observed on the fifth post-treatment day. The potential of ginger extract to inhibit lipid peroxidation induced by radiation (2 Gy) and ascorbate-ion stress in brain homogenate and its ability to scavenge highly reactive superoxide anions were evaluated. The 1000-microg/ml and 2000-microg/ml concentration of ginger extract showed the highest efficiency in scavenging free radicals and in inhibiting lipid peroxidation. The lipid peroxidation and superoxide-anion scavenging ability of the extract further supports its radioprotective properties. The results clearly establish the neurobehavioral efficacy of ginger extract and the antioxidant properties appear to be a contributing factor in its overall ability to modulate radiation-induced conditioned taste aversion. Ginger extract has tremendous potential for clinical applications in mitigation of radiation-induced emesis in humans.
Assuntos
Condicionamento Psicológico/efeitos dos fármacos , Extratos Vegetais/farmacologia , Paladar/efeitos dos fármacos , Zingiber officinale , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/efeitos da radiação , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Condicionamento Psicológico/efeitos da radiação , Relação Dose-Resposta a Droga , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos da radiação , Sequestradores de Radicais Livres/farmacologia , Raios gama , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Masculino , Malondialdeído/metabolismo , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Sacarina/administração & dosagem , Paladar/efeitos da radiação , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de TempoRESUMO
The increased use of mobile phones has raised the question of possible health effects of such devices, particularly the risk of cancer. It seems unlikely that the low-level radiofrequency (RF) radiation emitted by them would damage DNA directly, but its ability to act as a tumor promoter is less well characterized. In the current study, we evaluated the effect of low-level RF radiation on the development of cancer initiated in mice by ionizing radiation. Two hundred female CBA/S mice were randomized into four equal groups at the age of 3 to 5 weeks. The mice in all groups except the cage-control group were exposed to ionizing radiation at the beginning of the study and then to RF radiation for 1.5 h per day, 5 days a week for 78 weeks. One group was exposed to continuous NMT (Nordic Mobile Telephones)-type frequency-modulated RF radiation at a frequency of 902.5 MHz and a nominal average specific absorption rate (SAR) of 1.5 W/kg. Another group was exposed to pulsed GSM (Global System for Mobile)-type RF radiation (carrier-wave frequency 902.4 MHz, pulse frequency 217 Hz) at a nominal average SAR of 0.35 W/kg. The control animals were sham-exposed. Body weight, clinical signs, and food and water consumption were recorded regularly. Hematological examinations and histopathological analyses of all lesions and major tissues were performed on all animals. The RF-radiation exposures did not increase the incidence of any neoplastic lesion significantly. We conclude that the results do not provide evidence for cancer promotion by RF radiation emitted by mobile phones.
Assuntos
Neoplasias Induzidas por Radiação/etiologia , Telefone , Animais , Comportamento de Ingestão de Líquido/efeitos da radiação , Contagem de Eritrócitos , Comportamento Alimentar/efeitos da radiação , Feminino , Camundongos , Camundongos Endogâmicos CBA , Neoplasias Induzidas por Radiação/classificação , Tamanho do Órgão/efeitos da radiação , Raios XRESUMO
Recent findings have implicated endogenous opiates in radiation-induced behavioral change. The present experiment further investigated this hypothesis by observing alterations in morphine self-administration after irradiation. Under the presumption that the release of endogenous opiates would decrease the need for exogenously supplied morphine, we hypothesized that after radiation exposure morphine-experienced mice would self-administer less of the opiate. C57BL/6J mice had continuous access to two drinking flasks which contained either water or morphine in saccharine water. Irradiated mice drank significantly less morphine than did sham-irradiated controls. This decrease was naloxone-reversible and could not be entirely attributed to a generalized radiogenic hypodipsia or taste aversion. These results are consistent with the hypothesis that radiation-induced behavioral changes may be due, in part, to the fluctuations of endogenous opiates.
Assuntos
Comportamento de Ingestão de Líquido/efeitos da radiação , Endorfinas/fisiologia , Morfina/administração & dosagem , Naloxona/farmacologia , Animais , Radioisótopos de Cobalto , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sacarina , SoluçõesRESUMO
BACKGROUND: In a substantial proportion of depressed patients, stressful life events play a role in triggering the evolution of the illness. Exposure to stress has effects on different levels in laboratory animals as well and for the rat it has been shown that chronic mild stress (CMS) can cause antidepressant-reversible depressive-like effects. The adoption of the model to the mouse seems to be problematic, depending on the strain used and behavioural endpoint defined. Our aim was to evaluate the applicability of CMS to mice in order to induce behavioural alterations suggested to reflect depression-like symptoms. METHODOLOGY/PRINCIPAL FINDINGS: A weekly CMS protocol was applied to male mice of different mouse strains (D2Ola, BL/6J and BL/6N) and its impact on stress-sensitive behavioural measures (anhedonia-, anxiety- and depression-related parameters) and body weight was assessed. Overnight illumination as commonly used stressor in CMS protocols was particularly investigated in terms of its effect on general activity and subsequently derived saccharin intake. CMS application yielded strain-dependent behavioural and physiological responses including 'paradox' anxiolytic-like effects. Overnight illumination was found to be sufficient to mimic anhedonic-like behaviour in BL/6J mice when being applied as sole stressor. CONCLUSIONS/SIGNIFICANCE: The CMS procedure induced some behavioural changes that are compatible with the common expectations, i.e. 'anhedonic' behaviour, but in parallel behavioural alterations were observed which would be described as 'anomalous' (e.g. decreased anxiety). The results suggest that a shift in the pattern of circadian activity has a particular high impact on the anhedonic profile. Changes in activity in response to novelty seem to drive the 'anomalous' behavioural alterations as well.
Assuntos
Ansiedade/complicações , Estresse Psicológico/complicações , Animais , Peso Corporal/efeitos da radiação , Doença Crônica , Comportamento Consumatório , Comportamento de Ingestão de Líquido/efeitos da radiação , Luz , Masculino , Camundongos , Testes Neuropsicológicos , Sacarina/metabolismo , Fatores de Tempo , Aumento de Peso/efeitos da radiaçãoRESUMO
Feedback lighting provides illumination primarily during the subjective night (i.e., the photosensitive portion of the circadian cycle) in response to a given behavior. This technique has previously been used to test the nonparametric model of entrainment in nocturnal rodents. In three species (Rattus norvegicus, Mesocricetus auratus, and Mus musculus), the free-running period of the locomotor activity rhythm was similar whether the animals were exposed to continuous light or discrete light pulses occurring essentially only during the subjective night (i.e., feedback lighting). In the current experiments, feedback lighting was presented to squirrel monkeys so that light fell predominantly during the subjective night. Feedback lighting was linked to the drinking behavior in this diurnal primate so that when the animal drank, the lights went out. Despite the seemingly adverse predicament, the monkeys maintained regular circadian drinking rhythms. Furthermore, just as the period of the free-running activity rhythms of nocturnal rodents exposed to continuous light or feedback lighting were similar, the period of the drinking rhythms of the squirrel monkeys in continuous light and feedback lighting were comparable (25.6 +/- 0.1 and 25.9 +/- 0.1 hours, respectively), despite a substantial decrease in the total amount of light exposure associated with feedback lighting. The free-running period of monkeys exposed to continuous dark (24.5 +/- 0.1 hours) was significantly shorter than either of the two lighting conditions (P < 0.001). The results presented for the drinking rhythm were confirmed by examination of the temperature and activity rhythms. Therefore, discrete light pulses given predominately during the subjective night are capable of simulating the effects of continuous light on the free-running period of the circadian rhythms of a diurnal primate. The response of squirrel monkeys to feedback lighting thus lends further support for the model and suggests that the major entrainment mechanisms are similar in nocturnal rodents and diurnal primates.
Assuntos
Ritmo Circadiano/efeitos da radiação , Comportamento de Ingestão de Líquido/efeitos da radiação , Iluminação , Atividade Motora/efeitos da radiação , Animais , Temperatura Corporal , Escuridão , Retroalimentação , Ratos , Saimiri , ÁguaRESUMO
Free-running rhythms for eating, drinking, standing and walking activities were studied in two experiments with four cross-bred rams. In the first experiment the rhythms were entrained to a LD (12:12) (300:0) regimen. Following a change to continuous dim light (less than 2 lux) there was a suggestion of free-running activity for about three days in some of the variables. By the fourth day, however, the previously entrained rhythms had been damped out and were replaced by random patterns of activity in all variables. In the second experiment, two entraining agents were used: LD (12:12) (300:0) and restriction of feed to the light period only. There was again some indication of free-running activity for the first few days of continuous dim light (less than 2 lux) but by the fourth day only random patterns of activity were evident.
Assuntos
Comportamento Animal/efeitos da radiação , Ritmo Circadiano/efeitos da radiação , Luz , Ovinos/fisiologia , Animais , Comportamento de Ingestão de Líquido/efeitos da radiação , Comportamento Alimentar/efeitos da radiação , Masculino , Atividade Motora/efeitos da radiaçãoRESUMO
The conditions under which neophobia and enhanced neophobia occur in the albino rat were studied. Neophobia to a .1% saccharin solution was demonstrated in a 10-min single-bottle test. This neophobia was enhanced by pairing water ingestion with a radiation exposure of 100 r. or an injection of lithium chloride 24 hr prior to the saccharin test. In addition, it was found that the differences in consumption of saccharin in a 10-min single-bottle test due to neophobia and enhanced neophobia were produced by consistent differences in drinking rates which appeared early in the 10-min period. The disappearance of neophobia and enhanced neophobia in a 1-hr single-bottle test suggested that the effects of neophobia and enhanced neophobia are short-lived and are best measured in a brief single-bottle test. Finally, enhanced neophobia was not found when 2 days of water drinking were interposed between LiCl poisoning and saccharin testing.
Assuntos
Associação , Aprendizagem da Esquiva , Comportamento de Ingestão de Líquido , Paladar , Animais , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos da radiação , Extinção Psicológica , Lítio/intoxicação , Masculino , Radiação Ionizante , Ratos , Sacarina , Fatores de TempoRESUMO
Long-Evans male adult rats were exposed for sixteen weeks to 2450-MHz CW microwaves at an average power density of mW/cm2. The resulting dose rate was 1.23 (+/- 0.25SEM) mW/g. The animals were exposed eight hours a day, five days a week, for a total of 640 h in a monopole-above-ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and of food and water intakes indicated no statistically significant effects of microwave irradiation. Biweekly stabilimetric tests immediately after exposure revealed a significant depression of behavioral activity by 15 microwave-exposed rats as compared with 15 sham-exposed animals. Measures of locomotor activity based on revolutions of a running wheel, which were obtained during 12-h periods between each 8-h exposure, showed no significant effect of irradiation. Blood sampled after 2, 6, 10, and 14 weeks of exposure indicated slight alterations of sulfhydryl groups, and of red and white blood-cell counts. Measures of levels of 17-ketosteroids in urine at weeks 1, 5, 9, and 12 of exposure, and mass of adrenals, heart, and liver at the end of the sixteen-week period of exposure, revealed no indications of stress.