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1.
Horm Behav ; 124: 104781, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511968

RESUMO

Glucocorticoids (GCs) are thought to impact reproductive success, and ultimately fitness. In this study we focus specifically on the relationship between GCs and parental care. Captive bred Japanese quail (Coturnix japonica) do not show spontaneous parental care behavior, however this behavior can be induced through a sensitization procedure. We investigated how the GC status of Japanese quail relates to parental care in animals of both sexes exposed or not to a chick sensitization treatment. To assess GC status, we obtained baseline plasma and feather cort samples, and used the HPA-axis function test to assess stress responsiveness by examining the response to a standardized stressor as well as negative feedback efficacy through dexamethasone injection. Next, birds were either exposed to chicks overnight in a small enclosure (sensitization treatment) or were enclosed but not exposed to chicks (control). The following morning, adult behaviors were filmed in the presence of a fresh set of chicks for 20 min. A final serum GC sample was obtained to assess if exposure to novel chicks was perceived as stressful. In control animals, baseline GCs were associated with increased total parental care duration and decreased latency to first parental care event. Interestingly, the opposite relationship was found in the sensitization group. Finally, exposure to novel chicks was not associated with an increase in corticosterone in either group. Overall it appears that baseline GCs are correlated with parental care in captive bred Japanese quail, and that the relationship changes direction depending on whether or not sensitization has occurred.


Assuntos
Corticosterona/sangue , Coturnix/fisiologia , Comportamento de Nidação/fisiologia , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Corticosterona/metabolismo , Coturnix/sangue , Dexametasona/farmacologia , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Comportamento de Nidação/efeitos dos fármacos , Testes de Função Hipofisária/veterinária , Distribuição Aleatória , Reprodução/fisiologia , Maturidade Sexual/fisiologia
2.
Gen Comp Endocrinol ; 259: 85-92, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29170021

RESUMO

The conditions of captivity can cause chronic stress in wild animals. Newly-captured animals may experience weight loss, elevated glucocorticoid hormones, increased heart rate, increased resting adrenomedullary activation, and an altered heart rate response to acute stressors. As captivity conditions persist, chronic stress may decrease as animals adjust to the stressors of captivity. In this study, house sparrows (Passer domesticus) were captured from the wild, fitted with heart rate transmitters in a minor surgical process, and individually housed in an indoor bird facility. Mass, baseline corticosterone, resting heart rate, resting adrenomedullary activation, and the acute heart rate response to a sudden noise were measured over the course of the first 6 weeks of captivity. Birds lost weight during the first weeks of captivity, which was regained by week 5. Baseline corticosterone peaked at day 7, decreased sharply by day 11, and continued to decrease throughout the 6 weeks. Although heart rate in the first 24 h could not be collected, daytime heart rate decreased from day 1 through day 20, where it reached a stable plateau. Daytime heart rate variability decreased through the entire 6 weeks, which may indicate a gradual shift from sympathetic to parasympathetic nervous system regulation of heart rate. The acute heart rate response to a sudden noise lasted longer at day 6 than earlier or later in captivity. In conclusion, the data indicate that the different physiological systems associated with chronic stress adjust to captivity over different timelines.


Assuntos
Adaptação Fisiológica , Laboratórios , Pardais/fisiologia , Estresse Fisiológico , Animais , Animais Selvagens/fisiologia , Peso Corporal , Corticosterona/sangue , Feminino , Frequência Cardíaca/fisiologia , Masculino , Ruído , Reflexo de Sobressalto/fisiologia , Pardais/sangue
3.
Glia ; 64(8): 1298-313, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27158936

RESUMO

The efficacy of drugs targeting the CNS is influenced by their limited brain access, which can lead to complete pharmacoresistance. Recently a tissue-specific and selective upregulation of the multidrug efflux transporter ABCB1 or P-glycoprotein (P-gp) in the spinal cord of both patients and the mutant SOD1-G93A mouse model of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease that prevalently kills motor neurons has been reported. Here, we extended the analysis of P-gp expression in the SOD1-G93A ALS mouse model and found that P-gp upregulation was restricted to endothelial cells of the capillaries, while P-gp expression was not detected in other cells of the spinal cord parenchyma such as astrocytes, oligodendrocytes, and neurons. Using both in vitro human and mouse models of the blood-brain barrier (BBB), we found that mutant SOD1 astrocytes were driving P-gp upregulation in endothelial cells. In addition, a significant increase in reactive oxygen species production, Nrf2 and NFκB activation in endothelial cells exposed to mutant SOD1 astrocytes in both human and murine BBB models were observed. Most interestingly, astrocytes expressing FUS-H517Q, a different familial ALS-linked mutated gene, also drove NFκB-dependent upregulation of P-gp. However, the pathway was not dependent on oxidative stress but rather involved TNF-α release. Overall, these findings indicated that nuclear translocation of NFκB was a converging mechanism used by endothelial cells of the BBB to upregulate P-gp expression in mutant SOD1-linked ALS and possibly other forms of familial ALS. GLIA 2016 GLIA 2016;64:1298-1313.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Astrócitos/patologia , Barreira Hematoencefálica/patologia , Capilares/metabolismo , Capilares/patologia , Linhagem Celular , Técnicas de Cocultura , Modelos Animais de Doenças , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Camundongos Transgênicos , NF-kappa B/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Medula Espinal/metabolismo , Medula Espinal/patologia , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Regulação para Cima , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP
4.
PeerJ ; 6: e4961, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29892510

RESUMO

Despite decades of research, we still lack a complete understanding of what factors influence the transition of the necessary and adaptive acute stress response to what has become known as chronic stress. This gap in knowledge has illuminated the necessity for studies that examine the thresholds between these two sides of the stress response. Here, we determine how repeated exposure to acute stressors influences physiological and behavioral responses. In this repeated measures study, house sparrows (Passer domesticus) were exposed to a chronic stress protocol. We took physiological and behavioral measurements before, during, and after the protocol. Blood samples were used to assess four aspects of hypothalamic-pituitary-adrenal (HPA) axis function: baseline corticosterone, stress-induced corticosterone, negative feedback, and the maximal capacity to secrete corticosterone. We also assessed bacterial killing capacity and changes in uric acid concentration. Neophobia trials were used to assess behavioral changes throughout the protocol. We found no significant changes in HPA axis regulation in any of the four aspects we tested. However, we found that uric acid concentrations and neophobia significantly decreased after only four days of the chronic stress protocol, while bacterial killing capacity did not decrease until after eight days of exposure. These results indicate that different components of the stress response can be impacted by chronic stress on different timescales. Our results further indicate the importance of assessing multiple aspects of both physiology and behavior in order to understand how exposure to chronic stress may influence ability to cope with future challenges.

5.
Clin Ophthalmol ; 9: 1689-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26392749

RESUMO

INTRODUCTION: Corneal abrasions (CAs) are the most prevalent ocular injuries in the perioperative period. Previously, patients at our community hospital would wait for an ophthalmologist to be available to manage these minor injuries. To decrease this waiting period - and thereby increase patient satisfaction - we developed an anesthesiology-based protocol to manage minor CAs arising in the recovery room. The current study sought to assess this protocol's efficacy as well as further establish the incidence and some risk factors of CA. METHODS: This was a hospital-based, observational study. As per protocol, anesthesiologists saw and diagnosed any patient exhibiting symptoms of CA, after which they initiated a preestablished treatment regimen. To examine the efficacy of this protocol between March 2007 and December 2011, the number of CAs anesthesiologists managed and time to treatment were recorded. Additionally, the frequency of CAs was established along with some of their risk factors. RESULTS: Throughout the study period, there were 91,064 surgical cases, with 118 CAs (0.13% incidence). Anesthesiology alone managed 110 (93.22%) of these cases. The median time between the end of anesthesia to the time of prescribed ophthalmic medication was 156 minutes (first-third interquartile range: 108-219). All patients experienced resolution of symptoms by the morning following their complaint. Compared to the general surgical population, CA patients were older (P<0.01) and underwent longer surgeries (P<0.01). CONCLUSION: Minor CAs can be safely and effectively managed using an anesthesiology-based approach. Advanced age and longer surgery are confirmed as risk factors for these injuries.

6.
Radiother Oncol ; 104(1): 52-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22578806

RESUMO

PURPOSE: To quantify the post-radiotherapy 2-[(18)F]-fluoro-2-deoxyglucose (FDG) pulmonary uptake dose-response in lung cancer patients and determine its relationship with radiation pneumonitis symptoms. METHODS AND MATERIALS: The data from 24 patients treated for lung cancer with thoracic radiotherapy who received restaging PET/CT imaging between 4 and 12 weeks after radiotherapy completion were evaluated. Their radiation dose distribution was registered with the post-treatment restaging PET/CT. Using histogram analysis, the voxel average FDG-PET uptake vs. radiation dose was obtained for each case and linear regression was performed. The resulting slope, the pulmonary metabolic radiation response (PMRR), was used to characterize the dose-response. The Common Toxicity Criteria version 3 was used to score clinical pulmonary toxicity symptoms. Receiver operating characteristic (ROC) curves were used to determine the level of FDG uptake vs. dose, MLD, V(5), V(10), V(20), and V(30) that can best predict symptomatic and asymptomatic patients. RESULTS: The median time between radiotherapy completion and FDG-PET imaging was 59 days (range, 26-70 days). The median of the mean SUV from lung that received 0-5 Gy was 1.00 (range, 0.37-1.48), 5-10 Gy was 1.01 (range, 0.37-1.77), 10-20 Gy was 1.04 (0.42-1.53), and >20 Gy was 1.29 (range, 0.41-8.01). Using the dose range of 0 Gy to the maximum dose minus 10 Gy, hierarchical linear regression model of the radiation dose and normalized FDG uptake per case found an adequate fit with the linear model. Pneumonitis scores were: Grade 0 for 13, Grade 1 for 5, Grade 2 for 6, and Grade 3, 4 or 5 for none. Using a PMRR threshold of 0.017 yields an associated true positive rate of 0.67 and false positive rate of 0.15 with average error of 30%. A V(5) threshold of 57.6 gives an associated true positive rate of 0.67 and false positive rate of 0.05 with a 20% average error. CONCLUSION: The metabolic radiation pneumonitis dose-response was evaluated from post-treatment FDG-PET/CT imaging. Statistical modeling found a linear relationship. The FDG uptake dose-response and V(5) correlated with symptomatic radiation pneumonitis.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/diagnóstico por imagem , Compostos Radiofarmacêuticos , Idoso , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Doses de Radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
Mol Pharmacol ; 71(6): 1572-81, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17341653

RESUMO

Norepinephrine has potent antiepileptic properties, the pharmacology of which is unclear. Under conditions in which GABAergic inhibition is blocked, norepinephrine reduces hippocampal cornu ammonis 3 (CA3) epileptiform activity through alpha(2) adrenergic receptor (AR) activation on pyramidal cells. In this study, we investigated which alpha(2)AR subtype(s) mediates this effect. First, alpha(2)AR genomic expression patterns of 25 rat CA3 pyramidal cells were determined using real-time single-cell reverse transcription-polymerase chain reaction, demonstrating that 12 cells expressed alpha(2A)AR transcript; 3 of the 12 cells additionally expressed mRNA for alpha(2C)AR subtype and no cells possessing alpha(2B)AR mRNA. Hippocampal CA3 epileptiform activity was then examined using field potential recordings in brain slices. The selective alphaAR agonist 6-fluoronorepinephrine caused a reduction of CA3 epileptiform activity, as measured by decreased frequency of spontaneous epileptiform bursts. In the presence of betaAR blockade, concentration-response curves for AR agonists suggest that an alpha(2)AR mediates this response, as the rank order of potency was 5-bromo-N-(4,5-dihydro-1H-imidazol-2-yl)-6-quinoxalinamine (UK-14304) >or= epinephrine >6-fluoronorepinephrine > norepinephrine >>> phenylephrine. Finally, equilibrium dissociation constants (K(b)) of selective alphaAR antagonists were functionally determined to confirm the specific alpha(2)AR subtype inhibiting CA3 epileptiform activity. Apparent K(b) values calculated for atipamezole (1.7 nM), MK-912 (4.8 nM), BRL-44408 (15 nM), yohimbine (63 nM), ARC-239 (540 nM), prazosin (4900 nM), and terazosin (5000 nM) correlated best with affinities previously determined for the alpha(2A)AR subtype (r = 0.99, slope = 1.0). These results suggest that, under conditions of impaired GABAergic inhibition, activation of alpha(2A)ARs is primarily responsible for the antiepileptic actions of norepinephrine in the rat hippocampal CA3 region.


Assuntos
Agonistas Adrenérgicos/uso terapêutico , Epilepsia/prevenção & controle , Hipocampo/efeitos dos fármacos , Receptores Adrenérgicos alfa 2/metabolismo , Adrenérgicos/administração & dosagem , Agonistas Adrenérgicos/farmacologia , Animais , Catecolaminas/farmacologia , Epinefrina/farmacologia , Feminino , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 2/efeitos dos fármacos
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