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Resumen La variabilidad de la frecuencia cardiaca (VFC) se utiliza como una señal fisiológica para evaluar la reactividad psicofisiológica al estrés. El análisis en el dominio de la frecuencia de esta señal se ha usado para describir el papel del sistema nervioso autónomo en los procesos de adaptación al estrés. Sin embargo, el uso de medidas de tendencia central para reportar los resultados de distintas poblaciones desestima las diferencias individuales en la reacción frente al estrés. El objetivo de esta investigación fue caracterizar la reactividad cardiaca ante la evocación de eventos estresantes en población universitaria. Participaron 94 estudiantes de nuevo ingreso a la carrera de psicología, de dos universidades de México. Los resultados indican un decremento consistente en la banda de alta frecuencia ante la evocación de eventos estresantes, en comparación con la banda de baja frecuencia. La caracterización de la respuesta autonómica al estrés presenta dos subgrupos acoplados (co-activación y co-inhibición); y uno desacoplado. Nuestros hallazgos, ratifican la viabilidad de la banda de frecuencia alta de la VFC como un indicador estable de reactividad al estrés, y resaltan la importancia de las diferencias específicas de la actividad autonómica en la caracterización de la respuesta fisiológica al estrés.
Abstract Heart rate variability (HRV) is used as a reliable physiological signal to assess psychophysiological reactivity to stress. Frequency-domain mathematical analysis of the HRV signal provides metrics that are associated with the performance of the autonomic nervous system. However, the use of measures of central tendency to report global results in different populations underestimates individual differences in the way people react to stress and the clinical importance of this response. The objective of this research was to characterize cardiac reactivity to the evocation of stressful events in a university population. The participants were 94 new psychology students from two universities in Mexico. A psychophysiological stress assessment was performed to estimate cardiac reactivity; the evaluation consisted of the following conditions: 1) Baseline; 2) Evocation of stress; and 3) Recovery. The participants were sitting with their eyes closed and without moving during every single one of the conditions. Four subgroups were created depending on the type of cardiac reactivity to stress. The results indicate a significant consistent decrease in the high-frequency band when evoking stressful events, compared to the low-frequency band. Similar responses were observed between the low-frequency band and the high-frequency band in 60.6% of the cases, suggesting that the antagonistic autonomic balance between the two divisions of the ANS was scarce. According to the autonomic space model and the type of stress reactivity of each student, there were two subgroups characterized by co-activation and co-inhibition modes; and one subgroup characterized by uncoupled response mode. Our findings confirm the viability of the high-frequency band of HRV as a stable indicator of stress reactivity. Likewise, evidence is generated in favor of using evocative stress stimuli to assess physiological reactivity like more personal stressors. Lastly, the importance of specific differences in autonomic activity to characterize the physiological response to stress and its possible clinical utility to propose interventions and select techniques that most effectively benefit vulnerable populations are highlighted.
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The Novel Object Recognition task (NOR) is widely used to study vertebrates' memory. It has been proposed as an adequate model for studying memory in different taxonomic groups, allowing similar and comparable results. Although in cephalopods, several research reports could indicate that they recognize objects in their environment, it has not been tested as an experimental paradigm that allows studying different memory phases. This study shows that two-month-old and older Octopus maya subjects can differentiate between a new object and a known one, but one-month-old subjects cannot. Furthermore, we observed that octopuses use vision and tactile exploration of new objects to achieve object recognition, while familiar objects only need to be explored visually. To our knowledge, this is the first time showing an invertebrate performing the NOR task similarly to how it is performed in vertebrates. These results establish a guide to studying object recognition memory in octopuses and the ontological development of that memory.
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Octopodiformes , Reconhecimento Psicológico , Animais , Comportamento Exploratório , Percepção Visual , Reconhecimento Visual de ModelosRESUMO
The psychophysiological coherence model proposes that a heart rhythm pattern, known as heart rhythm coherence (HRC), is associated with dominant parasympathetic activity and the entrainment of respiratory function, blood pressure, and heart rhythms. Although the HRC pattern has primarily been assessed during wakefulness, changes in cardiac and autonomic activity that occur during sleep stages can also be associated with the HRC pattern. The objective of this study was to examine whether any differences in the HRC pattern could be detected among various sleep stages. Eighteen healthy young individuals participated in this study. Two consecutive polysomnographic (PSG) recordings were obtained from each participant, several segments of cardiac activity were obtained from the second PSG. The HRC pattern was quantitatively evaluated by calculating the HRC ratio (HRCR). The highest peaks in the coherence band (Coher-Peak), 0.1-Hz index, respiratory sinus arrhythmia (RSA), and heart rate (HR) were evaluated. A Friedman test showed significant differences among sleep stages in the Coher-Peak, 0.1-Hz index, RSA, and HR; the Coher-Peak and RSA values were lower in rapid eye movement (REM) sleep, while the 0.1-Hz and HR values were higher in REM sleep. Post hoc analyses identified significant differences between the N2 and REM sleep stages. Among the various sleep stages, HR and RSA measurements behaved independently of the HRC pattern, and the HRC pattern did not appear to be associated with the 0.1 Hz frequency. Further studies are required to identify the characteristics of the HRC pattern during sleep.
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Fases do Sono , Sono , Sistema Nervoso Autônomo , Frequência Cardíaca/fisiologia , Humanos , Projetos Piloto , Polissonografia , Sono/fisiologia , Fases do Sono/fisiologiaRESUMO
Sleep disturbances frequently occur in people with whiplash-associated disorder (WAD) and have been evaluated using questionnaires or actigraphy. It is not clear whether sleep architecture, as assessed by polysomnography (PSG), is altered in individuals with WAD. Additionally, in people with WAD, muscle dysfunction is observed during tasks performed during wakefulness. Thus, this study aimed to analyze the sleep architecture of patients with chronic WAD as well as to evaluate trapezius muscle activity during sleep. Nine women with chronic WAD and nine healthy age-matched women participated in the study. Two PSG recordings were conducted for each participant. Surface electromyography signal samples of the right and left trapezius, and mentonian muscles were obtained from N2, N3, and REM sleep stages for analysis. Significant differences were found in the percentages of total sleep time in the N1 and N2 stages between the two groups. While the muscle tone of the three muscles analyzed decreased progressively across the sleep stages in the healthy group, in the chronic WAD group, this decrement was observed only in the mentonian muscle, and the trapezius muscle continued to exhibit the same muscle tone throughout the sleep stages without atonia during REM sleep. The absence of trapezius muscle atonia during REM sleep in the WAD patients may be related to dysfunction of the mechanisms that regulate motor activity.
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Although motor activity is actively inhibited during rapid eye movement (REM) sleep, specific activations of the facial mimetic musculature have been observed during this stage, which may be associated with greater emotional dream mentation. Nevertheless, no specific biomarker of emotional valence or arousal related to dream content has been identified to date. In order to explore the electromyographic (EMG) activity (voltage, number, density and duration) of the corrugator and zygomaticus major muscles during REM sleep and its association with emotional dream mentation, this study performed a series of experimental awakenings after observing EMG facial activations during REM sleep. The study was performed with 12 healthy female participants using an 8-hr nighttime sleep recording. Emotional tone was evaluated by five blinded judges and final valence and intensity scores were obtained. Emotions were mentioned in 80.4% of dream reports. The voltage, number, density and duration of facial muscle contractions were greater for the corrugator muscle than for the zygomaticus muscle, whereas high positive emotions predicted the number (R2 0.601, p = 0.0001) and voltage (R2 0.332, p = 0.005) of the zygomaticus. Our findings suggest that zygomaticus events were predictive of the experience of positive affect during REM sleep in healthy women.
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Sonhos/fisiologia , Eletromiografia/métodos , Emoções/fisiologia , Expressão Facial , Sono REM/fisiologia , Adulto , Feminino , Voluntários Saudáveis , Humanos , Adulto JovemRESUMO
Abstract: Introduction: Autistic spectrum disorder (ASD) is characterized by difficulties in communication and social interaction. The theory of mind (TM) links social deficiencies in ASD with a difficulty in representing the mental states of other people. The Mu rhythm (8-13Hz) has been studied as an expression of the possible neuronal basis of TM. In ASD, the physiological reactivity of the Mu rhythm to motor events is affected. During sleep, there are also phenomena related to sensorimotor processing. Objective: To characterize the Mu rhythm in the sleep of children with level 1 ASD, ages six to 10, and compare it with control children paired by age and sex. Method: Polysomnographic records for two consecutive nights. The record of the second night was analyzed visually (the first was considered habituation) to identify and select Mu rhythm segments throughout the night. The extracted segments were analyzed using the fast Fourier transform and subsequently with t tests on the data of C3 and C4. Results: A significant difference was found in the power spectrums of C3 and C4t (1, 144) = 3.038, p = .003 and t (1, 144) = -2.301, p = .023, respectively. Discussion and conclusion: The results of this study are consistent with the morphological and topographic characteristics found in studies conducted during wakefulness. The results suggest that the Mu rhythm is caused intrinsically, without external sensory stimulation, and that there is a difference in this generation in the population with ASD.
Resumen: Introducción: El trastorno del espectro autista (TEA) se caracteriza por dificultades en la comunicación e interacción social. La teoría de la mente (TM) vincula las deficiencias sociales en el TEA con una dificultad para representar los estados mentales de otros. El ritmo Mu (8-13Hz) se ha estudiado como expresión del posible fundamento neuronal de la TM. En el TEA, la reactividad fisiológica del ritmo Mu a eventos motores se ve afectada. Durante el sueño también hay fenómenos relacionados con el procesamiento sensomotor. Objetivo: Caracterizar el ritmo Mu en el sueño de niños con TEA nivel 1, en edades de seis a 10 años, y compararlo con niños control pareados por edad y sexo Método: Registros polisomnográficos durante dos noches consecutivas. Se analizó visualmente el registro de la segunda noche (la primera se consideró de habituación) para identificar y seleccionar segmentos de ritmo Mu a lo largo de ella. Los segmentos extraídos fueron analizados por medio de la transformada rápida de Fourier y posteriormente con pruebas t sobre los datos de C3 y C4 Resultados: Se encontró una diferencia significativa en los espectros de potencia de C3 and C4t (1, 144) = 3.038, p = .003 y t (1, 144) = -2.301, p = .023, respectivamente. Discusión y conclusión: Los resultados de este estudio son consistentes con características morfológicas y topográficas encontradas en estudios hechos durante la vigilia. Los resultados sugieren que el ritmo Mu se estaría generando de manera intrínseca, sin estimulación sensorial externa, y que existe una diferencia en esta generación en población con TEA.
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Abstract: Introduction: Wake-sleep transition is a continuous, gradual process of change. Most studies evaluating electroencephalogram spectral power during this transition have used variance analysis (ANOVA). However, using this type of analysis does not allow one to detect specific changes in the statistical properties of a time series. Objective: To determine whether change point analysis (CPA) makes it possible to identify and characterize electroencephalographic, electromyographic, and cardiac changes during the wake-sleep transition through a cross-sectional study. Method: The study included 18 healthy volunteers (12 women and six men), from which polysomnography data were obtained during a two-minute transition. Heart rate, respiratory sinus arrhythmia, electroencephalogram spectral power, as well as electromyographic median and mean frequency and electromyographic root mean square were calculated in five-second segments. These segments were analyzed using repeated measures ANOVA, and CPA focused individually and for the group as a whole. Results: Repeated measures ANOVA and CPA by group found decreased levels of alpha and beta power and beta/delta index during wakefulness, and increased theta and delta power levels during sleep. CPA by individual found that only alpha power changed in all participants and failed to identify a specific moment when all the variables studied changed simultaneously. Discussion and conclusion: We consider that CPA provides additional information to statistical analyses such as ANOVA for the specific location of physiological changes during sleep-wake transition.
Resumen: Introducción: La transición vigilia-sueño es un proceso de cambio continuo y gradual. Los estudios que han evaluado el poder espectral del electroencefalograma (EEG) durante esta transición han usado principalmente el análisis de varianza (ANOVA). Sin embargo, con este tipo de análisis no se pueden ubicar con precisión los cambios en las propiedades estadísticas de series de tiempo. Objetivo: Evaluar si el análisis de punto de cambio (APC) permite identificar y caracterizar cambios electroencefalográficos, electromiográficos y cardiacos durante la transición vigilia-sueño mediante un estudio transversal descriptivo. Método: Participaron 18 voluntarios sanos (12 mujeres y seis hombres) a los cuales se les realizó una polisomnografía para determinar un periodo de transición de dos minutos. En segmentos de cinco segundos se calcularon la frecuencia cardiaca, arritmia del sinus respiratorio, frecuencia mediana y media cuadrática del electromiograma y poder espectral del EEG. Estos segmentos se analizaron con ANOVA de medidas repetidas y con el APC que se aplicó de forma grupal e individual. Resultados: Con el ANOVA de medidas repetidas y el APC grupal se encontraron disminución de la potencia alfa, beta e índice beta/delta durante la vigilia e incrementos de theta y delta durante el sueño. Con el APC individual no se identificó un momento específico en el que todas las variables estudiadas cambiaran simultáneamente; además, se encontró que sólo la potencia alfa cambió en todos los participantes. Discusión y conclusión: El APC aportó información adicional al ANOVA ya que permitió conocer la ubicación específica de los cambios en las variables fisiológicas estudiadas durante la transición vigilia-sueño.
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BACKGROUND: The physiological mechanisms that allow for sleeping in a vertical position, which is primordial for arboreal primates, have not been studied yet. METHODS: A non-invasive polysomnographic study of 6 spider monkeys (Ateles geoffroyi) was conducted. The relative beta power of the motor cortex and its linear relation with muscle tone in the facial mentalis muscle and the abductor caudae medialis muscle of the tail during wakefulness and sleep stages were calculated. RESULTS: A strong negative linear relationship (r = -.8, P = .03) was found between the relative power of the beta2 band in the left motor cortex and abductor caudae medialis muscle tone during delta sleep. CONCLUSIONS: The left motor cortex, through beta2 band activity, interacts with abductor caudae medialis muscle tonicity during delta sleep. This interaction takes part in the mechanisms that regulate the sleep postures.
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Atelinae/fisiologia , Tono Muscular , Músculo Esquelético/fisiologia , Sono , Animais , Eletroencefalografia/veterinária , MasculinoRESUMO
Objetivo: Identificar y describir las diferencias neuropsicológicas antes y después de resecar el tumor en 2 pacientes de 8 años de edad con una neoplasia en la fosa posterior. Metodología: Se realizó evaluación neuropsicológica pre y posquirúrgica a 2 pacientes de 8 años de edad del Instituto Nacional de Pediatría, uno femenino con quiste aracnoideo en cisterna paravermiana y otro masculino con meduloblastoma en vermis y se compararon los datos obtenidos antes de extirpación de tumor y después de ella. Para la obtención del IQ se aplicó el WISC-IV y para las otras funciones, la Evaluación Neuropsicológica Infantil (ENI), para niños de 5 a 16 años, obteniéndose sus valores en percentiles que se igualaron con la clasificación cualitativa. Resultados: Los 2 pacientes presentaron deficiencias en el IQ, en Funciones Cognitivas, en las Habilidades de Rendimiento Académico, así como en sus Funciones Ejecutivas. A pesar de que no se aplicó quimioterapia ni radioterapia, tanto antes de la cirugía, como después de la extirpación del tumor, empeorando dichas funciones después de la extirpación. Conclusiones: Los tumores en Fosa Posterior originan diversas alteraciones neuropsicológicas similares a las observadas con lesiones en la corteza cerebral, dichas alteraciones se hacen más severas después de la extirpación del tumor; esta evolución puede presentar un dilema a la luz de la Bioética: ¿Se prolonga la vida a expensas de mayor deterioro neurocognitivo al quitar el tumor, o no se opera para evitar mayor deterioro en la calidad de vida y se reduce el tiempo de vida?.
Aim: Identify and describe the neuropsychological differences before and after surgery in 2 patients 8 years of age with a tumor in the posterior fossa. Methodology: Neuropsychological assessment was performed before and after surgery to 2 patients (8 years of age), one female with arachnoid cyst in paravermian cyst and another male with medulloblastoma in vermis and we compared the data obtained before removal of tumor and after. We use the following Neuropsychological Tests: WISC-IV was applied to assess IQ and Child Neuropsychological Assessment (ENI) was to evaluate cognitive functions. Results: The 2 patients had deficits in IQ, cognitive functions, the academic performance skills and his executive skills, even without chemotherapy or radiotherapy, both before surgery and after removal of the tumor. These functions worsened after surgery. Conclusions: Posterior fossa tumors originate many various neuropsychological similar to those observed in cerebral cortex, these changes are most evident after removal of the tumor, this evolution can present a dilemma in light of Bioethics: Is justified to prolong the life at expense of neurocognitive impairment, after removing a big tumor, or not to operate preventing further deterioration in the quality of life and reducing the lifetime?.
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Humanos , Masculino , Feminino , Criança , Vermis Cerebelar , Cognição , Função Executiva , Fossa Craniana Posterior/patologia , Meduloblastoma/cirurgia , Testes Neuropsicológicos , Neoplasias Infratentoriais/cirurgia , Neoplasias Infratentoriais/complicações , Neoplasias Infratentoriais/psicologia , Cistos Aracnóideos/cirurgia , Bioética , Cisterna MagnaRESUMO
The sensorimotor cortex and the cerebellum are interconnected by the corticopontocerebellar (CPC) pathway and by neuronal groups such as the serotonergic system. Our aims were to determine the levels of cerebellar serotonin (5-HT) and lipid peroxidation (LP) after cortical iron injection and to analyze the motor function produced by the injury. Rats were divided into the following three groups: control, injured and recovering. Motor function was evaluated using the beam-walking test as an assessment of overall locomotor function and the footprint test as an assessment of gait. We also determined the levels of 5-HT and LP two and twenty days post-lesion. We found an increase in cerebellar 5-HT and a concomitant increase in LP in the pons and cerebellum of injured rats, which correlated with their motor deficits. Recovering rats showed normal 5-HT and LP levels. The increase of 5-HT in injured rats could be a result of serotonergic axonal injury after cortical iron injection. The LP and motor deficits could be due to impairments in neuronal connectivity affecting the corticospinal and CPC tracts and dysmetric stride could be indicative of an ataxic gait that involves the cerebellum.
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Cerebelo/metabolismo , Marcha , Peroxidação de Lipídeos , Atividade Motora , Degeneração Neural/metabolismo , Ponte/metabolismo , Serotonina/metabolismo , Animais , Compostos Ferrosos , Masculino , Degeneração Neural/induzido quimicamente , Degeneração Neural/fisiopatologia , Degeneração Neural/psicologia , Ratos , Ratos WistarRESUMO
OBJECTIVE: To determine the relationship between the degree of addiction (DA) and pattern of tobacco consumption (PTC) with anxiety and depression in smokers who want to quit smoking. MATERIAL AND METHODS: At admission to a smoking cessation program 495 smokers were surveyed to determine anxiety (IDARE Test), depression (Beck Inventory Test), DA (Fagerström Test) and PTC (pack-years). RESULTS: DA ≥ 6 points was associated with high anxiety levels RM=1.94, (IC95%1.02-3.72), p<0.04]; and with symptoms of severe depression; [RM=2.24, (IC95%1.00-4.99), p<0.04)]. The PCT equal or greater than 21 pack-year, was associated with moderate anxiety; [RM=3.19 (IC95%1.94-5.25), p<.00]; high anxiety; [RM=3.36 (IC95% 1.66-6-80), p<.00]; with moderate depressive symptoms; [RM=3.14, (IC95% 1.75-5-62), p<.00] and severe depressive symptoms; [RM=9.85, (IC95% 3.30-29.37), p<.00)]. CONCLUSION: A significant association exists in smokers having high GA and PCT, with moderate and high anxiety and depressive symptoms that should be considered during interventions to quit.
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Ansiedade/etiologia , Depressão/etiologia , Abandono do Hábito de Fumar/psicologia , Fumar/efeitos adversos , Fumar/terapia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Índice de Gravidade de DoençaRESUMO
Objetivo. Determinar la asociación entre el grado de adicción (GA) y patrón de consumo de tabaco (PCT) con la ansiedad y depresión en fumadores que quieren dejar de fumar (FQDF). Material y métodos. En 495 sujetos que acudieron a un programa para dejar de fumar se determinó la ansiedad (inventario IDARE) y depresión (cuestionario BECK), el GA (cuestionario de Fagerström) y PCT (paquetes-año). Resultados. El GA>= a 6 puntos se asoció con niveles de ansiedad altos [RM=1.94, (IC95 por ciento1.02-3.72), p<0.04] y con síntomas de depresión graves [RM=2.24, (IC95 por ciento1.00-4.99), p<0.04)]. El PCT>= a 21 paquetes año, se asoció con ansiedad rasgo media; [RM=3.19 (IC95 por ciento1.94-5.25), p<.00]; ansiedad rasgo alta; [RM=3.36 (IC95 por ciento 1.66-6-80), p<.00]; con depresión moderada; [RM=3.14, (IC95 por ciento 1.75-5-62) p<.00] y depresión grave; [RM=9.85, (IC95 por ciento 3.30-29.37), p<.00)]. Conclusión. Existe una asociación significativa en fumadores con alto GA y PCT, con la presencia de ansiedad y síntomas de depresión moderada a grave que deben considerarse en FQDF.
Objective. To determine the relationship between the degree of addiction (DA) and pattern of tobacco consumption (PTC) with anxiety and depression in smokers who want to quit smoking. Material and Methods. At admission to a smoking cessation program 495 smokers were surveyed to determine anxiety (IDARE Test), depression (Beck Inventory Test), DA (Fagerström Test) and PTC (pack-years). Results. DA>= 6 points was associated with high anxiety levels RM=1.94, (IC95 percent1.02-3.72), p<0.04]; and with symptoms of severe depression; [RM=2.24, (IC95 percent1.00-4.99), p<0.04)]. The PCT equal or greater than 21 pack-year, was associated with moderate anxiety; [RM=3.19 (IC95 percent1.94-5.25), p<.00]; high anxiety; [RM=3.36 (IC95 percent 1.66-6-80), p<.00]; with moderate depressive symptoms; [RM=3.14, (IC95 percent 1.75-5-62), p<.00] and severe depressive symptoms; [RM=9.85, (IC95 percent 3.30-29.37), p<.00)]. Conclusion. A significant association exists in smokers having high GA and PCT, with moderate and high anxiety and depressive symptoms that should be considered during interventions to quit.
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Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ansiedade/etiologia , Depressão/etiologia , Abandono do Hábito de Fumar/psicologia , Fumar/efeitos adversos , Fumar/terapia , México , Índice de Gravidade de DoençaRESUMO
The most common side effects following administration of antiepileptic drugs involve alterations in sleep architecture and varying degrees of daytime sleepiness. Oxcarbazepine is a drug that is approved as monotherapy for the treatment of partial seizures and generalized tonic-clonic seizures. However, there is no information about its effects on sleep pattern organization; therefore, the objective of this work was to analyze such effects. Animals (Wistar rats) exhibited three different behavioral and electrophysiological states of vigilance: wakefulness, slow wave sleep (SWS), and rapid eye movement (REM) sleep. Oral treatment with oxcarbazepine (100 mg/kg) produced an increment in total sleep time throughout the recording period. This increment involved both SWS and REM sleep. Mean duration of the REM sleep phase was not affected. In contrast, the frequency of this sleep phase increased significantly across the 10-hour period. REM sleep latency shortened significantly. Results obtained in this work indicate that oxcarbazepine's acute effects point to hypnotic properties.
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Anticonvulsivantes/uso terapêutico , Carbamazepina/análogos & derivados , Sono/efeitos dos fármacos , Administração Oral , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/fisiologia , Carbamazepina/farmacologia , Eletroencefalografia , Eletromiografia/métodos , Masculino , Músculos do Pescoço/fisiologia , Oxcarbazepina , Ratos , Ratos Wistar , Sono REM/efeitos dos fármacos , Fatores de Tempo , Vigília/efeitos dos fármacosRESUMO
BACKGROUND: It has been demonstrated that the interrelation between pain and sleep produces changes in sleep patterns and pain perception. Although some evidences suggest that sleep and pain may interact in a complex way, polysomnographic studies in animals with acute nociception are limited in number. AIMS: This study was carried out in order to evaluate the effect of intra-articular knee injection of uric acid on sleep-wake patterns. METHODS: Surgical electrode implantation was performed in seven anesthetized Wistar rats to carry out 10 h polysomnographic recordings. Acute nociception was induced by the intra-articular administration of 30% uric acid crystals into the knee joint of the right hind limb. Two recordings before and after intra-articular drug administration were obtained. Sleep-wake parameters were classified as (i) wakefulness (W), (ii) slow wave sleep (SWS), and (iii) rapid eye movement (REM) sleep. Frequency and duration from each parameter were evaluated under the two above-mentioned conditions. RESULTS: Intra-articular administration of uric acid induced: (i) an increased duration of wakefulness (p=0.014), (ii) a decrement in the duration (p=0.001) and number of events (p=0.027) in REM sleep, and (iii) a decrement in the total sleep time (p=0.001). SWS did not present statistical differences between groups. CONCLUSIONS: These data suggest that a nociceptive stimulus, induced by the intra-articular administration of uric acid, alters the sleep-wake equilibrium with REM sleep being particularly altered. However, further research concerning pain-sleep interaction is needed.
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Artrite Gotosa/psicologia , Dor/psicologia , Sono/fisiologia , Animais , Nível de Alerta/efeitos dos fármacos , Artrite Gotosa/induzido quimicamente , Artrite Gotosa/complicações , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Eletrodos Implantados , Eletroencefalografia , Membro Posterior/fisiologia , Injeções Intra-Articulares , Masculino , Dor/complicações , Medição da Dor , Polissonografia , Ratos , Ratos Wistar , Fases do Sono/fisiologia , Sono REM/efeitos dos fármacos , Ácido Úrico , Vigília/efeitos dos fármacosRESUMO
Norepinephrine (NE) plays an important role in motor recovery after brain damage. Most studies concerning NE activity have been performed in the cerebellum, while the role of the pons, the site where the norepinephrinergic locus coeruleus is located, has not yet been elucidated. For this work, we studied the changes in cerebellar and pontine NE content in sham-operated (n = 17), motor cortex injured (n = 6) and recovered rats (n = 12). Motor effects were assessed by means of footprint analysis and sensorimotor evaluation. It was found that after cortical brain damage, the stride length decreases while the stride angle increases after 6 h post-surgery, while the sensorimotor evaluation showed an increase in the motor deficit. Recovery was observed after 24 h. NE content increased in the pons after 6 h and returned to normal levels in recovered rats, with no significant changes observed in the cerebellum. Based on the functional remote inhibition, it is possible that NE exerts an autoinhibitory effect in the pons after motor cortical ablation. On the other hand, the absence of an effect in the cerebellum suggests that cerebellar NE activity related to damage and/or recovery is limited to discrete areas of the structure.
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Cerebelo/metabolismo , Córtex Motor/lesões , Norepinefrina/metabolismo , Ponte/metabolismo , Animais , Cerebelo/fisiopatologia , Lateralidade Funcional/fisiologia , Técnicas In Vitro , Locomoção/fisiologia , Masculino , Córtex Motor/fisiopatologia , Ponte/fisiopatologia , Ratos , Ratos WistarRESUMO
It has been reported that norepinephrine (NE) plays an important role in recovery after brain damage. However, the role of the pons, the site where the norepinephrinergic locus coeruleus (LC) is located, has not been elucidated. In order to study the changes in the pontine NE content in either noninjured, injured or recovered rats, we used 35 animals trained to walk across to a walkway where their footprints were recorded. Subsequently, 17 trained rats were sham-operated while 18 were injured by means of an ablation of the right motor cortex representative of the hindlimb. From the injured rats, 6 were sacrificed 6 hr before surgery in order to obtain the pons, while all the remaining rats were recorded in the walkway 6, 24 and 48 hr post-surgery. Then, rats were sacrificed by decapitation, the pons was removed and each hemisphere was prepared for the chromatographic analysis of NE. Results showed that after cortical brain damage, the length of the stride decreased while the angle of the stride increased 6 hr post-surgery. Recovery was observed after 24 hr. NE increased in the pons after 6 hr and returned to normal levels when rats had recovered. This suggests that cortical damage elicits NE changes in the LC that could reorganize the system to lead the recovery process. Such findings must be taken in account when pharmacotherapy with antidepressants or antipsychotics that act on norepinephrine-containing neuronal systems are prescribed in patients after stroke.
Assuntos
Córtex Motor/fisiologia , Norepinefrina/metabolismo , Ponte/metabolismo , Animais , Vias Eferentes/fisiologia , Lateralidade Funcional/fisiologia , Membro Posterior/inervação , Membro Posterior/fisiologia , Locus Cerúleo/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Ratos , Ratos WistarRESUMO
Electrophysiological and behavioral characteristics of the states of vigilance were analyzed in chronically implanted specimens of the turkey Meleagris gallopavo (M. gallopavo). Five different states of vigilance were observed throughout the nyctohemeral period: active wakefulness (AW), quiet wakefulness (QW), drowsiness (D), slow wave sleep (SWS) and rapid eye movement (REM) sleep. These states exhibit characteristics similar to those described in other bird species. Sleep periods displayed a polyphasic distribution; however, they showed the tendency to concentrate between 2100 and 0900 h in spite of the fact that the recordings were carried out under constant illumination. Sleep period occupied 45.71% of the nyctohemeral cycle, 43.33% corresponded to SWS, while 2.38% to REM sleep. The average duration of the REM sleep phase was very short, lasting 7.7+/-0.55 s (mean+/-S.D.). In contrast, its frequency was very high with an average recurrence of 268+/-63 phases throughout the nyctohemeral cycle. The short duration of REM sleep phase presented by the turkey as by other bird species studied up to now may be dependent upon genetic factors shared by this group of vertebrates.
Assuntos
Nível de Alerta/fisiologia , Fases do Sono , Sono/fisiologia , Perus/fisiologia , Animais , Eletroencefalografia , Polissonografia/métodosRESUMO
Existen numerosas substancias, de estructura química diversa que han sido utilizadas como inductoras de sueño. Sin embargo, debido a que producen efectos colaterales indeseables, constantemente son substituidas por fármacos de reciente creación. Este trabajo se llevó a cabo con el propósito de analizar el efecto sobre el sueño de una beta lactama de 1.5 benzodiazepina, administrada intraperitonealmente (0.9 mg/kg) a ratas wistar. Los resultados indican que esta substancia incrementa de manera significativa, tanto al sueño lento como al paradójico a expensas de la vigilia. La lactancia de la primera fase de sueño paradójico, se prolonga significativamente. Se concluye que esta substancia facilita la presencia de sueño, manifestándose su acción durante un período relativamente largo
Assuntos
Animais , Ratos , Barbitúricos/antagonistas & inibidores , Benzodiazepinas/antagonistas & inibidores , Diazepam/farmacologia , Eletromiografia/métodos , Flurazepam , Hipnóticos e Sedativos/farmacologia , Nitrazepam , Pentobarbital/farmacocinética , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Sono , TemazepamRESUMO
El propósito de este trabajo fue analizar el efecto de un derivado de la benzodiazepina sobre el ciclo vigilia-sueño, que no había sido estudiado. Para este propósito, se le administraron a ratas Wistar 0.9 mg/kg de un derivado clorado de la beta lactama de 1,5 benzodiazepina por vía intraperitoneal, analizando su acción mediante diez horas de registro poligráfico contínuo. Los resultados muestran que esta substancia disminuye el estado de vigilia e incrementan ligeramente el sueño lento y, de manera estadísticamente significativa (p<0.05), el sueño paradójico. Asimismo, la latencia de la primera fase de sueño paradójico se reduce de manera importante. Estos hallazgos indican que la substancia, analizada bajo las condiciones experimentales descritas, facilita la inducción y el mantenimiento del sueño
Assuntos
Ratos , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Benzodiazepinas/farmacocinética , Diazepam/administração & dosagem , Diazepam/efeitos adversos , Diazepam/farmacocinética , Eletromiografia/classificação , Eletromiografia/estatística & dados numéricos , Eletromiografia/métodos , Nitrazepam/administração & dosagem , Nitrazepam/efeitos adversos , Nitrazepam/farmacocinética , Sono REM , Sono REM/fisiologia , Sono , Sono/fisiologia , Vigília/efeitos dos fármacos , Vigília/fisiologiaRESUMO
Se estudiaron los estados de vigilancia de iguanas adultas Ctenosaura similis. Se observaron 4 estados diferentes: vigilia activa, vigilia pasiva, sueño pasivo y sueno MOR o activo. Durante el sueño pasivo, el cual fue de larga duración, los animales premanecían relajados completamente inmóviles. El sueño activo, que duraba unos cuantos segundos, se caracterizó por presentar movimientos oculares rápidos (simples o conjugados) y otras manifestaciones motoras tales como sacudidas de los miembros, movimientos de la lengua, etc. Este estado de sueño, siempre era precedido de sueño pasivo. Desde el punto de vista electoencefalográfico no se observaron las fases de sueño características de los vertebrados homeotermos, puesto que durante el sueño conductual no se presentaron las ondas lentas de gran amplitud que son típicas de la fase de sueño lento. Más bien, las actividad cerebral disminuía de amplitud cuando los animales pasaban de la vigilia al reposo. Un signo electoencefalográfico sobresaliente fue la presencia de espigas que se presentaban principalmente durante el reposo. El análisis de otras variables electrofisiológicas indica que la frecuencia cardiaca disminuyee cuando el animal pasa del estado de vigilia al del sueño conductual, presentándose marcadas arritmias a medida que el sueño se prolonga. Durante los breves periodos de sueño activo la frecuencia cardíaca se incrementó repentinamente, alcanzando algunas veces niveles semejantes a los de la vigilia. La actividad muscular disminuye al mínimo rápidamente cuando el animal passa de la vigilia al sueño conductual, sin mostrar modificación adicional hasta que se presentan los periodos de sueño activo, durante los cuales se observa una reactivación momentánea. Se concluye que, si bien debido al grado de desarrollado cerebral de los reptiles, no se presenta la actividad electoencefalográfica característica de las fases de sueño de los animales con cerebro más desarrollado, sí se presenta claramente el sueño, incluyendo una fase de movimientos oculares rápidos, análoga a la de los vertebrados superiores