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1.
Community Ment Health J ; 58(1): 78-86, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582951

RESUMO

The present study aimed to clarify the process of peer support formation and the promotion of recovery in people using psychiatric day care. From January to March 2014, semi-structured interviews were conducted with 18 participants with mental illness living in the community in Japan. The qualitative data were analyzed using a modified grounded theory approach. The results described a two-stage process: (1) awareness of peers with similar disability and distress and (2) formation and utilization of peer support. These results suggest that adjusting the environment and engaging in activities assisting others are useful for facilitating peer support and promoting the recovery of users in psychiatric day care.


Assuntos
Hospital Dia , Transtornos Mentais , Aconselhamento/métodos , Humanos , Japão , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Grupo Associado , Pesquisa Qualitativa
2.
J Cogn Neurosci ; 27(3): 453-63, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25244117

RESUMO

Oscillatory brain activity is known to play an essential role in information processing in working memory. Recent studies have indicated that alpha activity (8-13 Hz) in the parieto-occipital area is strongly modulated in working memory tasks. However, the function of alpha activity in working memory is open to several interpretations, such that alpha activity may be a direct neural correlate of information processing in working memory or may reflect disengagement from information processing in other brain areas. To examine the functional contribution of alpha activity to visuospatial working memory, we introduced visuospatial distractors during a delay period and examined neural activity from the whole brain using magnetoencephalography. The strength of event-related alpha activity was estimated using the temporal spectral evolution (TSE) method. The results were as follows: (1) an increase of alpha activity during the delay period as indicated by elevated TSE curves was observed in parieto-occipital sensors in both the working memory task and a control task that did not require working memory; and (2) an increase of alpha activity during the delay period was not observed when distractors were presented, although TSE curves were constructed only from correct trials. These results indicate that the increase of alpha activity is not directly related to information processing in working memory but rather reflects the disengagement of attention from the visuospatial input.


Assuntos
Ritmo alfa/fisiologia , Atenção/fisiologia , Magnetoencefalografia/métodos , Memória de Curto Prazo/fisiologia , Lobo Occipital/fisiologia , Lobo Parietal/fisiologia , Percepção Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Psychiatry Clin Neurosci ; 66(3): 203-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22443242

RESUMO

AIM: The present study examined whether the self-efficacy of interpersonal behavior influenced the interpersonal behavior of schizophrenia patients using psychiatric day-care services. METHODS: Thirty-nine patients with schizophrenia were examined with the Interpersonal Relations subscale of the Life Assessment Scale for Mentally Ill, the Self-efficacy Scale of Interpersonal Behavior, the Brief Assessment of Cognition in Schizophrenia-Japanese version, and the Positive and Negative Syndrome Scale. RESULTS: The Life Assessment Scale for Mentally Ill score was significantly correlated with the self-efficacy of interpersonal behavior, and was also significantly correlated with neurocognitive functions and negative symptoms. However, the Self-efficacy Scale of Interpersonal Behavior score was not correlated with neurocognitive functions and negative symptoms. To examine the causal correlations between the above social, psychological and clinical factors, multiple regression analysis was performed with the self-efficacy of interpersonal behavior, neurocognitive functions, and negative symptoms as the independent variables and interpersonal behavior as the dependent variable. The self-efficacy of interpersonal behavior was found to contribute to interpersonal behavior as well as neurocognitive functions. CONCLUSION: The self-efficacy of interpersonal behavior contributed to the interpersonal behavior as well as the neurocognitive functions in the case of schizophrenia patients in the community. This suggested that interventions targeting the self-efficacy of interpersonal behavior, as well as those targeting neurocognitive functions, were important to improve the interpersonal behavior of schizophrenia patients undergoing psychiatric rehabilitation in the community.


Assuntos
Relações Interpessoais , Esquizofrenia/reabilitação , Psicologia do Esquizofrênico , Autoeficácia , Adulto , Cognição/fisiologia , Hospital Dia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise de Regressão , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-20526606

RESUMO

Spontaneous respiratory bursts which begin in the pre-Bötzinger complex were recorded from the hypoglossal (XIIth) nerve rootlets of in vitro slices prepared from newborn mice. First, we examined the respiratory bursts before and after a midline or para-midline transection which spared the caudal raphe nuclei: the raphe obscurus and raphe pallidus. After a midline transection, the respiratory bursts in both half-slices were desynchronized and had slightly decreased amplitudes and frequencies. After a para-midline transection, the bursts continued with similar frequencies in the half slice containing the raphe obscurus and raphe pallidus. Second, to analyze the effects of modulation by the raphe obscurus and raphe pallidus, a dorsal or ventral midline lesion was used to damage either the raphe obscurus or raphe pallidus. After a dorsal lesion, the synchronized respiratory bursts persisted with slightly decreased frequencies. In contrast, after a ventral lesion, the bursts were almost completely abolished, but recovered significantly after the addition of 5-HT. The present results demonstrated that the pre-Bötzinger complex on each side of the medulla can independently generate rhythmic respiratory activity. It is suggested that the 5-HT released from the ventral part of the raphe nuclei (predominantly the raphe pallidus) plays a critical role in sustaining rhythmic respiratory bursts.


Assuntos
Lateralidade Funcional/fisiologia , Bulbo/fisiologia , Núcleos da Rafe/fisiologia , Fenômenos Fisiológicos Respiratórios , Animais , Animais Recém-Nascidos , Axotomia , Lateralidade Funcional/efeitos dos fármacos , Nervo Hipoglosso/efeitos dos fármacos , Nervo Hipoglosso/fisiologia , Ketanserina/farmacologia , Bulbo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Técnicas de Cultura de Órgãos , Núcleos da Rafe/efeitos dos fármacos , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia
5.
Neurosci Res ; 143: 13-19, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29778809

RESUMO

Propofol (2, 6-diisopropylphenol) is one of the most popular intravenous anesthetic agents. In this study, we compared the effects of propofol on inhibitory postsynaptic currents (IPSCs) induced by single and paired electrical stimulations in CA1 pyramidal cells (CA1-PCs) and dentate gyrus granule cells (DG-GCs) in rat hippocampal slices using the whole cell patch-clamp technique. In the absence of propofol, the amplitude of evoked IPSC by single stimulation and decay time constants were stable in both CA1-PCs and DG-GCs for 30 min. Propofol (1 µM and 10 µM) increased both IPSC amplitude in CA1-PCs, but not in DG-GCs. Further, using a paired pulse stimulation protocol, the ratio of IPSC amplitudes (the second response: A2/the first response: A1) was increased by propofol in CA1, but not in DG-GCs. These results suggest that propofol selectively affects IPSCs in CA1-PCs, which is similar to previously reported actions of benzodiazepines.


Assuntos
Região CA1 Hipocampal/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Propofol/farmacologia , Animais , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Giro Denteado/citologia , Giro Denteado/fisiologia , Potenciais da Membrana , Técnicas de Patch-Clamp , Células Piramidais , Ratos , Ratos Wistar , Transmissão Sináptica/efeitos dos fármacos , Ácido gama-Aminobutírico/fisiologia
6.
PLoS One ; 14(10): e0223819, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618271

RESUMO

OBJECTIVE: Focusing on people with schizophrenia spectrum disorders living in the community, the present study aims to examine the characteristics of and gender differences in self-disclosure to first acquaintances, and to clarify the relationship between self-disclosure and subjective well-being. METHODS: Participants (32 men and 30 women with schizophrenia spectrum disorders) were examined using the subjective well-being inventory, an original self-disclosure scale for people with mental illness, as well as the Rosenberg self-esteem scale, the Link devaluation-discrimination scale, and the affiliation scale. RESULTS: The self-disclosure content domains in descending order were as follows: "living conditions," "own strengths," "experiences of distress," and "mental illness and psychiatric disability." There were no significant gender differences in self-disclosure in the total and domain scores. Multiple regression analyses by gender revealed that: (1) in men, decreasing feelings of ill-being were significantly predicted by self-disclosure about "living conditions," self-esteem, and perceived stigma; (2) in women, increasing feelings of well-being were significantly predicted by self-disclosure about "own strengths," self-esteem, and sensitivity to rejection. CONCLUSIONS: Self-disclosure to first acquaintances was related to subjective well-being in people with schizophrenia spectrum disorders living in the community. This result supports the recovery model and the strengths model. It suggests the importance of interventions targeting self-disclosure to first acquaintances about experiences as human beings, such as "living conditions" and "own strengths," as it relates to subjective well-being in community-based mental health rehabilitation.


Assuntos
Psicologia do Esquizofrênico , Autorrevelação , Estigma Social , Adulto , Feminino , Amigos , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Autorrelato , Fatores Socioeconômicos , Adulto Jovem
7.
Neurosci Res ; 56(3): 322-31, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16962678

RESUMO

In the present study we first examined the possible involvement of the putative neurotransmitters gamma-aminobutyric acid (GABA) and serotonin (5-HT) in raphe-induced facilitatory or inhibitory effects on the respiratory activity of rats. Secondly, we investigated the possibility of spinal projections of GABAergic and serotonergic neurons from the medullary raphe nuclei to the phrenic motor nucleus (PMN). We observed that an intravenous (i.v.) injection of (+)-bicuculline, a GABA(A) receptor antagonist, significantly reduced respiratory inhibition induced by electrical stimulation of the raphe magnus (RM) or the raphe obscurus (RO). On the other hand, an i.v. injection of methysergide, a broad-spectrum 5-HT receptor antagonist, significantly reduced the respiratory facilitation induced by electrical stimulation of the raphe pallidus (RP) or RO. By using a combined method of retrograde tracing with Texas Red injected into the PMN region at segments C4 and C5 and immunohistochemical labeling, we observed that glutamic acid decarboxylase (GAD; a GABA synthesizing enzyme) immunopositive and Texas Red double labeled neurons were predominantly localized in the RM, and additionally in the RO. However 5-HT immunopositive and Texas Red double-labeled neurons were predominantly localized in the RP, and additionally in the RO and RM. These findings suggest that RM-, or RO-induced inhibitory effects, are transmitted, at least in part, to the PMN via a direct GABAergic descending pathway. The RP-, or RO-induced facilitatory effects in rats however, are transmitted via a serotonergic descending pathway.


Assuntos
Neurônios/fisiologia , Núcleos da Rafe/citologia , Respiração , Serotonina/metabolismo , Ácido gama-Aminobutírico/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Bicuculina/farmacologia , Mapeamento Encefálico , Estimulação Elétrica/métodos , Feminino , Antagonistas GABAérgicos/farmacologia , Glutamato Descarboxilase/metabolismo , Imuno-Histoquímica/métodos , Masculino , Metisergida/farmacologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Respiração/efeitos dos fármacos , Respiração/efeitos da radiação , Antagonistas da Serotonina/farmacologia , Fatores de Tempo
8.
J Geriatr Phys Ther ; 39(4): 159-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26352519

RESUMO

BACKGROUND AND PURPOSE: In dual-task situations, postural control is closely associated with attentional cost. Previous studies have reported age-related differences between attentional cost and postural control, but little is known about the association in conditions with a one-legged standing posture. The purpose of this study was to determine age-related differences in postural control and attentional cost while performing tasks at various difficulty levels in a one-legged standing posture. METHODS: In total, 29 healthy older adults aged 64 to 78 years [15 males, 14 females, mean (SD) = 71.0 (3.8) years] and 29 healthy young adults aged 20 to 26 years [14 males, 15 females, mean (SD) = 22.5 (1.5) years] participated in this study. We measured the reaction time, trunk accelerations, and lower limb muscle activity under 3 different one-legged standing conditions-on a firm surface, on a soft surface with a urethane mat, and on a softer more unstable surface with 2 piled urethane mats. Reaction time as an indication of attentional cost was measured by pressing a handheld button as quickly as possible in response to an auditory stimulus. A 2-way repeated-measures analysis of variance was performed to examine the differences between the 3 task conditions and the 2 age groups for each outcome. RESULTS AND DISCUSSION: Trunk accelerations showed a statistically significant group-by-condition interaction in the anteroposterior (F = 9.1, P < .05), mediolateral (F = 9.9, P < .05), and vertical (F = 9.3, P < .05) directions. Muscle activity did not show a statistically significant group-by-condition interaction, but there was a significant main effect of condition in the tibialis anterior muscle (F = 33.1, P < .01) and medial gastrocnemius muscle (F = 14.7, P < .01) in young adults and the tibialis anterior muscle (F = 24.8, P < .01) and medial gastrocnemius muscle (F = 10.8, P < .01) in older adults. In addition, there was a statistically significant interaction in reaction time (F = 8.2, P < .05) for group-by-condition. CONCLUSIONS: The study results confirmed that reaction times in older adults are more prolonged than young adults in the same challenging postural control condition.


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Músculo Esquelético/fisiologia , Equilíbrio Postural/fisiologia , Idoso , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Pressão , Tempo de Reação/fisiologia
9.
Front Psychol ; 7: 497, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148110

RESUMO

Recent studies have indicated that computerized cognitive training is effective as therapy for reducing the cognitive decline with aging and the dysfunction associated with neuropsychiatric illness. Although cognitive trainings that targets a specific function and multi-domain cognitive training have both been shown to have significant effects, we need one simple behavioral training paradigm to improve multiple domains of cognitive functions easily and simultaneously. We had developed a new computerized task that seeks to engage the cognitive functions of planning, mental calculation, and divergent thinking based on a working memory task in a single task. The purpose of this study was to assess the cognitive features of our new task by comparing the scores of seven known neuropsychological batteries in healthy elderly subjects. The relationships between performance in our task and the scores obtained by the neuropsychological batteries were examined. The percentage of correct performance on our task was correlated with the scores on the category fluency test, the digit span backward task, and the Trail making test B. Stepwise multiple regression analyses revealed that the scores on the category fluency test and the Trail making test B showed significant positive correlations with the percentage of correct performance on our task. Although the present study did not show high correlations between the percentage of correct performance on our task and working memory functions as a primary target, we observed mid-level correlations between the percentage of correct performance on our task and functions for divided attention and word fluency. Our new task requires not only working memory, but also attention and divergent thinking. Thus, this task might be a useful tool for training multiple cognitive functions simultaneously.

10.
Neuroreport ; 16(9): 1003-7, 2005 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-15931077

RESUMO

We compared the effects of midazolam, one of the popular benzodiazepines, on inhibitory postsynaptic currents in CA3 pyramidal cells with those in CA1 pyramidal cells in rat hippocampal slices. With all of the midazolam concentrations tested, the conductance of the evoked inhibitory postsynaptic current of the CA3 and CA1 pyramidal cells was significantly larger than the control, and increased in a dose-dependent manner. The normalized conductance of the inhibitory postsynaptic currents of the CA3 and CA1 pyramidal cells was not significantly different. However, we found that midazolam significantly prolonged the decay time of inhibitory postsynaptic currents of CA3 pyramidal cells. The results suggest that the differential effect of midazolam on the inhibitory postsynaptic currents could be due to the different decay kinetics, which depend on the gamma-aminobutyric acid type A receptor subunit compositions of the CA3 and CA1 pyramidal cells.


Assuntos
Moduladores GABAérgicos/farmacologia , Hipocampo/citologia , Midazolam/farmacologia , Inibição Neural/efeitos dos fármacos , Células Piramidais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Estimulação Elétrica/métodos , Hipocampo/efeitos dos fármacos , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Potenciais da Membrana/efeitos da radiação , Técnicas de Patch-Clamp/métodos , Células Piramidais/fisiologia , Ratos , Ratos Wistar , Transmissão Sináptica/fisiologia
11.
J Comp Neurol ; 474(4): 546-61, 2004 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-15174072

RESUMO

The purpose of this study was 1). to characterize the morphology of lumbar commissural neurons (CNs) with reticulospinal inputs and 2). to quantitate their activity during locomotor rhythm generation. Intraaxonal recordings at the L4-7 level of the spinal cord were obtained in 67 neurons in the decerebrate, paralyzed cat. Fourteen of them were subsequently nearly fully visualized following their intraaxonal injection with the tracer neurobiotin. All 14 were CNs with axons projecting across the midline of the spinal cord. Their somata were located mainly in lamina VIII and additionally in laminae VII-VI. Most of the lamina VIII CNs were excited monosynaptically from reticulospinal pathways. They were judged to be interneuronal CNs if they had no, or a short, rostral projection. These CNs commonly gave off multiple axon collaterals in and around their somata's segmental level. They projected mainly to laminae VIII-VII and some additionally to lamina IX. Some laminae VIII and the laminae VII-VI CNs were excited polysynaptically from reticulospinal pathways or were not excited. They were judged to be long propriospinal or ascending tract CNs because they had only an ascending axon. Most lamina VIII CNs discharged rhythmically during fictive locomotion evoked by stimulation of the mesencephalic locomotor region, exhibiting one peak per locomotor cycle. The peak was in phase with neurographic activity of either a left or a right hindlimb extensor nerve. These results suggested that lamina VIII CNs are reciprocally connected bilaterally at each segmental level. Such an arrangement suggests their participation in the generation and coordination of reciprocal and bilateral locomotor activity.


Assuntos
Mapeamento Encefálico , Interneurônios/citologia , Interneurônios/fisiologia , Locomoção/fisiologia , Medula Espinal/citologia , Medula Espinal/fisiologia , Animais , Tronco Encefálico/citologia , Tronco Encefálico/fisiologia , Gatos , Denervação , Eletrofisiologia , Região Lombossacral/anatomia & histologia , Região Lombossacral/fisiologia , Microeletrodos , Vias Neurais/citologia , Vias Neurais/fisiologia
12.
Prog Brain Res ; 143: 341-51, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14653178

RESUMO

This chapter provides a conceptual overview of the role and operation of higher structures of the central nervous system (CNS) in the control of posture and locomotion in the mammal, including the nonhuman primate and the human. Both quadrupedal and bipedal locomotion require the integrated neural control of multiple body segments against gravity. During development, and in selected instances in the adult, motor learning is required, particularly for merging anticipatory and reactive CNS processes, the latter being necessary after tripping and stumbling. We have recently found that the fastigial nucleus (FN) of the cerebellum in the cat plays a particularly important role in the control of locomotion, by virtue of its critical position in uniting the cerebro-cerebellar and the spino-cerebellar loops of neural activity that participate in the integrated control of multiple body segments. Further understanding of the CNS structures that achieve this integration has come from our recent study of an intact nonhuman primate, the Japanese monkey, Macaca fuscata, as it learns to elaborate bipedal locomotion rather than its normal quadrupedal fashion. Based on findings from these two animal species, we now present a model of the overall integrated control of posture and locomotion that features the combined operation of parallel and distributed neural circuitry throughout the CNS.


Assuntos
Núcleos Cerebelares/fisiologia , Atividade Motora/fisiologia , Animais , Sistema Nervoso Central/fisiologia , Humanos , Macaca/fisiologia , Postura/fisiologia
13.
Prog Brain Res ; 143: 183-90, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14653163

RESUMO

The operant-trained Japanese monkey, Macaca fuscata, can walk with both a quadrupedal (Qp) and a bipedal (Bp) gait on the surface of a treadmill belt, which moves at different speeds. The animal can also learn to transform its locomotor pattern from Qp to Bp, and vice versa, without a break in forward walking speed. This nonhuman primate model provides an intriguing opportunity to compare the kinematics of multiple body segments during Qp and Bp walking of the same subject. We found that M. fuscata selects a postural strategy and limb-kinematic parameters appropriate for the execution of both gaits. We propose that the basic locomotor rhythm-generating mechanisms of the brainstem and spinal cord, which are genetically endowed and relatively automatized, are used for the execution of both the Qp and Bp gait. The latter requires in addition, however, some higher-level circuitry which is shaped substantially by motor learning mechanisms.


Assuntos
Membro Posterior/fisiologia , Articulações/fisiologia , Macaca/fisiologia , Atividade Motora/fisiologia , Postura/fisiologia , Animais , Fenômenos Biomecânicos
14.
Prog Brain Res ; 143: 239-49, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14653169

RESUMO

In vertebrates, the descending reticulospinal pathway is the primary means of conveying locomotor command signals from higher motor centers to spinal interneuronal circuits, the latter including the central pattern generators for locomotion. The pathway is morphologically heterogeneous, being composed of various types of inparallel-descending axons, which terminate with different arborization patterns in the spinal cord. Such morphology suggests that this pathway and its target spinal interneurons comprise varying types of functional subunits, which have a wide variety of functional roles, as dictated by command signals from the higher motor centers. Corticoreticular fibers are one of the major output pathways from the motor cortex to the brainstem. They project widely and diffusely within the pontomedullary reticular formation. Such a diffuse projection pattern seems well suited to combining and integrating the function of the various types of reticulospinal neurons, which are widely scattered throughout the pontomedullary reticular formation. The corticoreticular-reticulospinal-spinal interneuronal connections appear to operate as a cohesive, yet flexible, control system for the elaboration of a wide variety of movements, including those that combine goal-directed locomotion with other motor actions.


Assuntos
Interneurônios/fisiologia , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Formação Reticular/fisiologia , Medula Espinal/fisiologia , Animais , Axônios/fisiologia , Axônios/ultraestrutura , Interneurônios/ultraestrutura , Vias Neurais/fisiologia , Vias Neurais/ultraestrutura , Transmissão Sináptica/fisiologia
15.
Brain Res ; 1003(1-2): 176-82, 2004 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-15019577

RESUMO

To examine regional differences of synaptic transmission, the effects of midazolam were observed on inhibitory postsynaptic currents (IPSCs) in CA1 pyramidal cells (CA1-PCs) and dentate gyrus granule cells (DG-GCs) in rat hippocampal slices. Midazolam is one of the most popular benzodiazepines. The monosynaptic IPSCs in the CA1-PCs and DG-GCs were evoked by electrical stimulation of GABAergic interneurons and recorded by whole cell patch-clamp techniques. The effects of specific concentrations of midazolam (0.3, 1, 10 and 75 microM) on the IPSCs in CA1-PCs and DG-GCs were examined at particular membrane potentials (20 mV steps, from -120 to +40 mV). In all midazolam concentrations tested, the conductance of the IPSCs was significantly larger than that in control and was increased by increasing the concentration of midazolam in CA1-PCs (normalized conductance, 0.3 microM, 121%; 1 microM, 125%; 10 microM, 147%; 75 microM, 147%). However, midazolam did not significantly change the conductance of the IPSCs in DG-GCs (normalized conductance, 0.3 microM, 92%; 1 microM, 92%; 10 microM, 91%; 75 microM, 115%). The normalized conductance was significantly different between the CA1-PCs and DG-GCs in 1 and 10 microM midazolam. The results strongly suggest that the differential effects of midazolam on IPSCs in CA1-PCs and DG-GCs could be, at least in part, due to the different sensitivity to midazolam of the GABA(A) receptor subtypes.


Assuntos
Giro Denteado/efeitos dos fármacos , Midazolam/farmacologia , Inibição Neural/efeitos dos fármacos , Células Piramidais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Giro Denteado/fisiologia , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Inibição Neural/fisiologia , Células Piramidais/fisiologia , Ratos , Transmissão Sináptica/fisiologia
16.
Brain Nerve ; 62(11): 1117-28, 2010 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-21068448

RESUMO

One of the fundamental characteristics of animal is locomotion. Although not visually apparent, goal-directed locomotor movements are always accompanied by automatic adjustment of muscle tone and postural reactions. Because the basic and essential mechanisms that control postural muscle tone and locomotion are located in the brainstem and spinal cord, a variety of locomotor behaviors are achieved by the projections from the forebrain structures (cerebral cortex, basal ganglia, and limbic-hypothalamic systems) and cerebellum to the brainstem-spinal cord. In this short review, we particularly focus on the role of the brainstem and spinal cord in the control of postural muscle tone and generation of locomotor rhythm. Abnormalities in the convergence inputs from the forebrain structures to the brainstem-spinal cord are further discussed in relation to the pathogenesis of disturbances in locomotor control.


Assuntos
Tronco Encefálico/fisiologia , Locomoção/fisiologia , Medula Espinal/fisiologia , Animais , Córtex Cerebral/fisiologia , Vias Eferentes/fisiologia , Humanos , Tono Muscular/fisiologia
17.
J Physiol Sci ; 60(4): 303-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20419361

RESUMO

Isolated upper cervical slice preparations were prepared from neonatal mice to examine whether spontaneous respiratory activity could be generated in the preparations. By using brainstem-spinal cord preparations, we first recorded from the cervical C1-C2 and C4 ventral roots rhythmic bursts which were synchronized with respiratory burst activity of the hypoglossal (XIIth) nerve. Following transection just above the C1 segment, smaller and slower rhythmic bursts still persisted in the C1/C2 ventral roots and these were synchronized with those in the C4 ventral root. The present result, that a bursting rhythm remained in the C1/C2 slices, suggests that the spinal neuronal circuit for generating respiratory rhythm is localized in the upper cervical segments which contain upper cervical inspiratory neurons.


Assuntos
Tronco Encefálico/fisiologia , Respiração , Medula Espinal/fisiologia , Animais , Animais Recém-Nascidos , Nervo Hipoglosso/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Neurônios/fisiologia , Centro Respiratório/fisiologia , Raízes Nervosas Espinhais/fisiologia
18.
Am J Phys Med Rehabil ; 88(9): 719-26, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18971767

RESUMO

OBJECTIVE: To determine the morphologic and histologic effects of electrical stimulation (ES) used to prevent muscle atrophy, and to investigate the effects of ES at different stimulation frequencies in preventing atrophy in different muscle fiber types. DESIGN: Rats in the hindlimb suspended (HS) plus ES group were subjected to 20- and 30-Hz stimulation (ES1, ES2) every other day for 2 wks. RESULTS: In soleus, the muscle weight, muscle fiber cross-sectional area, and the number of type I muscle fibers were significantly decreased in the HS and HS + ES2 groups, whereas they were maintained in the HS + ES1 group. This indicated that ES at 20 Hz could suppress muscle atrophy and retain muscle fiber type proportions, based on histologic properties. In extensor digitorum longus, the muscle weight, muscle fiber cross-sectional area, and the number of type II muscle fibers were significantly decreased in the HS group, whereas they were maintained in the HS + ES groups. This indicated that ES at either 20 Hz or 30 Hz could suppress muscle atrophy, and retain muscle fiber type proportions, based on histologic properties. ES at 30 Hz also had positive effects in maintaining the extensor digitorum longus muscle. CONCLUSIONS: These results suggest that short periods of low-intensity, low-stimulation frequency (20 Hz) ES of muscle during periods of inactivity could maintain changes in both morphologic and histologic properties of the slow-twitch muscle fibers (soleus). Short periods of low-intensity, high-stimulation frequency (30 Hz) ES of muscle during periods of inactivity could maintain changes in both morphologic and histologic properties of the fast-twitch muscle fibers (extensor digitorum longus).


Assuntos
Terapia por Estimulação Elétrica , Atrofia Muscular/prevenção & controle , Animais , Elevação dos Membros Posteriores/efeitos adversos , Masculino , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Ratos , Ratos Wistar
19.
Artigo em Inglês | MEDLINE | ID: mdl-16404604

RESUMO

The present study was undertaken to examine the effects of electrical stimulation of the medullary raphe nuclei on respiration in rats anesthetized with ketamine and xylazine. Train pulse stimuli (100 Hz, 10-30 microA) were applied in the regions of the caudal raphe nuclei: the raphe magnus (RM), raphe pallidus (RP) and raphe obscurus (RO). Stimulation of the RM depressed inspiratory movements measured by means of an abdominal pneumograph, whereas stimulation of the RP augmented inspiratory movements. It was revealed that stimulation of the RO induced either inhibitory or facilitatory effects on respiratory movements depending on the stimulation sites. These findings confirm and extend previous studies concerning the effects of raphe stimulation on respiratory activity in cats. The present results demonstrate that in rats the caudal raphe nuclei are involved in respiratory control.


Assuntos
Núcleos da Rafe/citologia , Núcleos da Rafe/fisiologia , Mecânica Respiratória/fisiologia , Anestesia , Animais , Mapeamento Encefálico , Estimulação Elétrica , Feminino , Masculino , Inibição Neural/fisiologia , Ratos , Ratos Wistar , Volume de Ventilação Pulmonar/fisiologia
20.
J Neurophysiol ; 91(3): 1183-92, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14973325

RESUMO

The aims of the study were twofold: (1) to verify the hypothesis that neurons in the fastigial nucleus excite and inhibit hindlimb alpha-motoneurons and (2) to determine both the supraspinal and spinal relays of these actions. Axons of fastigial neurons were stimulated at the level of their decussation in the cerebellum, within the hook bundle of Russell, in deeply anesthetized cats with only the right side of the spinal cord intact. The resulting excitatory postsynaptic potentials and inhibitory postsynaptic potentials were analyzed in motoneurons on the left side of the lumbar enlargement. Postsynaptic potentials evoked by the first effective stimulus were induced at latencies <2 ms from descending volleys and <1 ms from interneuronally relayed volleys, indicating a trisynaptic coupling between the fastigial neurons and alpha-motoneurons, via commissural interneurons on the right side. Cerebellar stimulation facilitated the synaptic actions of both vestibulospinal and reticulospinal tract fibers. However, the study leads to the conclusion that trisynaptic fastigial actions are mediated via vestibulospinal rather than reticulospinal tract fibers [stimulated within the lateral vestibular nucleus (LVN) and the medial longitudinal fascicle (MLF), respectively]. This is indicated firstly by collision between descending volleys induced by cerebellar stimulation and volleys evoked by LVN stimuli but not by MLF stimuli. Second, similar cerebellar actions were evoked before and after a transection of MLF. Mutual facilitation between the fastigial and reticulospinal, as well as between the fastigial and vestibulospinal actions, could be due to the previously reported integration of descending vestibulospinal and reticulospinal commands by spinal commissural interneurons.


Assuntos
Cerebelo/fisiologia , Membro Posterior/inervação , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Neurônios/fisiologia , Animais , Axônios/fisiologia , Tronco Encefálico/fisiologia , Gatos , Cerebelo/citologia , Estimulação Elétrica , Eletrodos Implantados , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Interneurônios/fisiologia , Fibras Nervosas/fisiologia , Núcleo Vestibular Lateral/fisiologia
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