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[PMID]:28778915
[Au] Autor:Grotle AK; Garcia EA; Huo Y; Stone AJ
[Ad] Endereço:Department of Kinesiology and Health Education, The University of Texas at Austin, Austin Texas.
[Ti] Título:Temporal changes in the exercise pressor reflex in type 1 diabetic rats.
[So] Source:Am J Physiol Heart Circ Physiol;313(4):H708-H714, 2017 Oct 01.
[Is] ISSN:1522-1539
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Previous studies have shown that diabetic peripheral neuropathy affects both unmyelinated and myelinated afferents, similar to those evoking the exercise pressor reflex. However, the effect of type 1 diabetes (T1DM) on this reflex is not known. We examined, in decerebrate male and female T1DM [streptozotocin (STZ)] and healthy control (CTL) rats, pressor and cardioaccelerator responses to isometric contraction of the hindlimb muscles during the early and late stages of the disease. STZ (50 mg/kg) was injected to induce diabetes, and experiments were conducted at 1, 3, and 6 wk after injection. On the day of the experiment, we statically contracted the hindlimb muscles by stimulating the sciatic nerve and measured changes in mean arterial pressure and heart rate. We found that the pressor but not cardioaccelerator response was exaggerated in STZ rats at 1 wk (STZ: 21 ± 3 mmHg, = 10, and CTL: 14 ± 2 mmHg, = 10, < 0.05) and at 3 wk (STZ: 26 ± 5 mmHg, = 10, and CTL: 17 ± 3 mmHg, = 11, < 0.05) after injection. However, at 6 wk, and only in male rats, both the pressor (STZ: 13 ± 3 mmHg, = 12, and CTL: 17 ± 3 mmHg, = 13, < 0.05) and cardioaccelerator responses (STZ: 7 ± 3 beats/min, = 12, and CTL: 10 ± 3 beats/min, = 13, < 0.05) to contraction were significantly attenuated in STZ rats compared with CTL rats. These data indicate that T1DM exaggerates the exercise pressor reflex during the early stages of the disease in both male and female rats. Conversely, T1DM attenuates this reflex in the late stage of the disease in male but not female rats. This is the first study to provide evidence that the pressor and cardioaccelerator responses to skeletal muscle contraction vary depending on the duration of type 1 diabetes.
[Mh] Termos MeSH primário: Pressão Arterial/fisiologia
Diabetes Mellitus Experimental/fisiopatologia
Diabetes Mellitus Tipo 1/fisiopatologia
Frequência Cardíaca/fisiologia
Condicionamento Físico Animal
Reflexo Anormal/fisiologia
Vasoconstrição/fisiologia
[Mh] Termos MeSH secundário: Animais
Estudos de Casos e Controles
Estado de Descerebração
Estimulação Elétrica
Feminino
Membro Posterior
Masculino
Contração Muscular/fisiologia
Músculo Esquelético
Ratos
Ratos Sprague-Dawley
Reflexo
Nervo Isquiático
Fatores Sexuais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170806
[St] Status:MEDLINE
[do] DOI:10.1152/ajpheart.00399.2017


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[PMID]:28733447
[Au] Autor:Downey RM; Mizuno M; Mitchell JH; Vongpatanasin W; Smith SA
[Ad] Endereço:Department of Health Care Sciences, University of Texas Southwestern Medical Center, Dallas, Texas.
[Ti] Título:Mineralocorticoid receptor antagonists attenuate exaggerated exercise pressor reflex responses in hypertensive rats.
[So] Source:Am J Physiol Heart Circ Physiol;313(4):H788-H794, 2017 Oct 01.
[Is] ISSN:1522-1539
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Exaggerated heart rate (HR) and blood pressure responses to exercise in hypertension are mediated, in part, by overactivity of the exercise pressor reflex (EPR). The mechanisms underlying this EPR dysfunction have not been fully elucidated. Previous studies have shown that stimulation of mineralocorticoid receptors (MRs) with exogenous administration of aldosterone in normal, healthy rats reproduces the EPR overactivity characteristic of hypertensive animals. Conversely, the purpose of this study was to examine whether antagonizing MR with spironolactone (SPIR) or eplerenone (EPL) in decerebrated hypertensive rats ameliorates abnormal EPR function. Changes in mean arterial pressure (MAP) and HR induced by EPR or muscle mechanoreflex (a component of EPR) activation were assessed in normotensive Wistar-Kyoto rats and spontaneously hypertensive rats (SHRs) fed normal chow (NC) or a customized diet containing either SPIR or EPL for 3 wk. SHRs treated with SPIR or EPL had significantly attenuated MAP responses to EPR (NC: 45 ± 7 mmHg, SPIR: 26 ± 4 mmHg, and EPL: 24 ± 5 mmHg, = 0.02) and mechanoreflex (NC: 34 ± 9 mmHg, SPIR: 17 ± 3 mmHg, and EPL: 15 ± 3 mmHg, = 0.03) activation. SHRs treated with SPIR or EPL also showed significantly attenuated HR responses to EPR (NC: 17 ± 3 beats/min, SPIR: 9 ± 1 beats/min, and EPL: 9 ± 2 beats/min, = 0.01) and mechanoreflex (NC: 15 ± 3 beats/min, SPIR: 6 ± 1 beats/min, and EPL: 7 ± 1 beats/min, = 0.01) activation. Wistar-Kyoto rats treated with SPIR did not demonstrate significant differences in MAP or HR responses to EPR or mechanoreflex activation. The data suggest that antagonizing MRs may be an effective strategy for the treatment of EPR overactivity in hypertension. Exaggerated cardiovascular responses to exercise in hypertensive patients are linked with overactive exercise pressor reflexes (EPRs). Administration of low-dose mineralocorticoid receptor antagonists (spironolactone or eplerenone) effectively ameliorates abnormal EPR function in hypertension. Effective treatment of EPR overactivity may reduce the cardiovascular risks associated with physical activity in hypertension.
[Mh] Termos MeSH primário: Pressão Sanguínea/efeitos dos fármacos
Hipertensão/fisiopatologia
Antagonistas de Receptores de Mineralocorticoides/farmacologia
[Mh] Termos MeSH secundário: Animais
Pressão Arterial/efeitos dos fármacos
Estado de Descerebração
Frequência Cardíaca/efeitos dos fármacos
Masculino
Músculo Esquelético/efeitos dos fármacos
Ratos
Ratos Endogâmicos SHR
Ratos Endogâmicos WKY
Reflexo/efeitos dos fármacos
Espironolactona/análogos & derivados
Espironolactona/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Mineralocorticoid Receptor Antagonists); 27O7W4T232 (Spironolactone); 6995V82D0B (eplerenone)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171108
[Lr] Data última revisão:
171108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170723
[St] Status:MEDLINE
[do] DOI:10.1152/ajpheart.00155.2017


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[PMID]:28724548
[Au] Autor:Rollins KS; Smith JR; Esau PJ; Kempf EA; Hopkins TD; Copp SW
[Ad] Endereço:Department of Kinesiology, Kansas State University, Manhattan, Kansas.
[Ti] Título:Bradykinin does not acutely sensitize the reflex pressor response during hindlimb skeletal muscle stretch in decerebrate rats.
[So] Source:Am J Physiol Regul Integr Comp Physiol;313(4):R463-R472, 2017 Oct 01.
[Is] ISSN:1522-1490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hindlimb skeletal muscle stretch (i.e., selective activation of the muscle mechanoreflex) in decerebrate rats evokes reflex increases in blood pressure and sympathetic nerve activity. Bradykinin has been found to sensitize mechanogated channels through a bradykinin B2 receptor-dependent mechanism. Moreover, bradykinin B2 receptor expression on sensory neurons is increased following chronic femoral artery ligation in the rat (a model of simulated peripheral artery disease). We tested the hypothesis that injection of bradykinin into the arterial supply of a hindlimb in decerebrate, unanesthetized rats would acutely augment (i.e., sensitize) the increase in blood pressure and renal sympathetic nerve activity during hindlimb muscle stretch to a greater extent in rats with a ligated femoral artery than in rats with a freely perfused femoral artery. The pressor response during static hindlimb muscle stretch was compared before and after hindlimb arterial injection of 0.5 µg of bradykinin. Injection of bradykinin increased blood pressure to a greater extent in "ligated" ( = 10) than "freely perfused" ( = 10) rats. The increase in blood pressure during hindlimb muscle stretch, however, was not different before vs. after bradykinin injection in freely perfused (14 ± 2 and 15 ± 2 mmHg for pre- and post-bradykinin, respectively, = 0.62) or ligated (15 ± 3 and 14 ± 2 mmHg for pre- and post-bradykinin, respectively, = 0.80) rats. Likewise, the increase in renal sympathetic nerve activity during stretch was not different before vs. after bradykinin injection in either group of rats. We conclude that bradykinin did not acutely sensitize the pressor response during hindlimb skeletal muscle stretch in freely perfused or ligated decerebrate rats.
[Mh] Termos MeSH primário: Bradicinina/farmacologia
Estado de Descerebração/fisiopatologia
Membro Posterior/efeitos dos fármacos
Contração Muscular/efeitos dos fármacos
Músculo Esquelético/efeitos dos fármacos
Reflexo/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Barorreflexo/efeitos dos fármacos
Barorreflexo/fisiologia
Pressão Sanguínea/efeitos dos fármacos
Pressão Sanguínea/fisiologia
Membro Posterior/fisiopatologia
Masculino
Contração Muscular/fisiologia
Músculo Esquelético/fisiopatologia
Ratos
Ratos Sprague-Dawley
Reflexo/fisiologia
Sistema Nervoso Simpático/efeitos dos fármacos
Sistema Nervoso Simpático/fisiopatologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
S8TIM42R2W (Bradykinin)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170721
[St] Status:MEDLINE
[do] DOI:10.1152/ajpregu.00187.2017


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[PMID]:28433644
[Au] Autor:Bezdudnaya T; Marchenko V; Zholudeva LV; Spruance VM; Lane MA
[Ad] Endereço:Department of Neurobiology and Anatomy, College of Medicine, Drexel University, 2900 W Queen Lane, Philadelphia, PA 19129, USA.
[Ti] Título:Supraspinal respiratory plasticity following acute cervical spinal cord injury.
[So] Source:Exp Neurol;293:181-189, 2017 Jul.
[Is] ISSN:1090-2430
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Impaired breathing is a devastating result of high cervical spinal cord injuries (SCI) due to partial or full denervation of phrenic motoneurons, which innervate the diaphragm - a primary muscle of respiration. Consequently, people with cervical level injuries often become dependent on assisted ventilation and are susceptible to secondary complications. However, there is mounting evidence for limited spontaneous recovery of respiratory function following injury, demonstrating the neuroplastic potential of respiratory networks. Although many studies have shown such plasticity at the level of the spinal cord, much less is known about the changes occurring at supraspinal levels post-SCI. The goal of this study was to determine functional reorganization of respiratory neurons in the medulla acutely (>4h) following high cervical SCI. Experiments were conducted in decerebrate, unanesthetized, vagus intact and artificially ventilated rats. In this preparation, spontaneous recovery of ipsilateral phrenic nerve activity was observed within 4 to 6h following an incomplete, C2 hemisection (C2Hx). Electrophysiological mapping of the ventrolateral medulla showed a reorganization of inspiratory and expiratory sites ipsilateral to injury. These changes included i) decreased respiratory activity within the caudal ventral respiratory group (cVRG; location of bulbospinal expiratory neurons); ii) increased proportion of expiratory phase activity within the rostral ventral respiratory group (rVRG; location of inspiratory bulbo-spinal neurons); iii) increased respiratory activity within ventral reticular nuclei, including lateral reticular (LRN) and paragigantocellular (LPGi) nuclei. We conclude that disruption of descending and ascending connections between the medulla and spinal cord leads to immediate functional reorganization within the supraspinal respiratory network, including neurons within the ventral respiratory column and adjacent reticular nuclei.
[Mh] Termos MeSH primário: Mapeamento Encefálico
Diafragma/fisiopatologia
Plasticidade Neuronal/fisiologia
Centro Respiratório/fisiopatologia
Traumatismos da Medula Espinal/complicações
[Mh] Termos MeSH secundário: Potenciais de Ação/fisiologia
Animais
Medula Cervical
Estado de Descerebração/fisiopatologia
Modelos Animais de Doenças
Lateralidade Funcional
Masculino
Neurônios/fisiologia
Nervo Frênico/lesões
Nervo Frênico/fisiopatologia
Ratos
Ratos Sprague-Dawley
Centro Respiratório/patologia
Simpatectomia Química
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170424
[St] Status:MEDLINE


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[PMID]:28188328
[Au] Autor:Miller DM; DeMayo WM; Bourdages GH; Wittman SR; Yates BJ; McCall AA
[Ad] Endereço:Department of Otolaryngology, Eye and Ear Institute, University of Pittsburgh, 203 Lothrop Street, Suite 500, Pittsburgh, PA, 15213, USA.
[Ti] Título:Neurons in the pontomedullary reticular formation receive converging inputs from the hindlimb and labyrinth.
[So] Source:Exp Brain Res;235(4):1195-1207, 2017 Apr.
[Is] ISSN:1432-1106
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The integration of inputs from vestibular and proprioceptive sensors within the central nervous system is critical to postural regulation. We recently demonstrated in both decerebrate and conscious cats that labyrinthine and hindlimb inputs converge onto vestibular nucleus neurons. The pontomedullary reticular formation (pmRF) also plays a key role in postural control, and additionally participates in regulating locomotion. Thus, we hypothesized that like vestibular nucleus neurons, pmRF neurons integrate inputs from the limb and labyrinth. To test this hypothesis, we recorded the responses of pmRF neurons to passive ramp-and-hold movements of the hindlimb and to whole-body tilts, in both decerebrate and conscious felines. We found that pmRF neuronal activity was modulated by hindlimb movement in the rostral-caudal plane. Most neurons in both decerebrate (83% of units) and conscious (61% of units) animals encoded both flexion and extension movements of the hindlimb. In addition, hindlimb somatosensory inputs converged with vestibular inputs onto pmRF neurons in both preparations. Pontomedullary reticular formation neurons receiving convergent vestibular and limb inputs likely participate in balance control by governing reticulospinal outflow.
[Mh] Termos MeSH primário: Neurônios Motores/fisiologia
Formação Reticular/citologia
Vestíbulo do Labirinto/fisiologia
[Mh] Termos MeSH secundário: Potenciais de Ação/fisiologia
Animais
Mapeamento Encefálico
Gatos
Estado de Consciência
Estado de Descerebração
Estimulação Elétrica
Feminino
Membro Posterior/fisiologia
Masculino
Movimento/fisiologia
Rotação
Vestíbulo do Labirinto/inervação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170830
[Lr] Data última revisão:
170830
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170212
[St] Status:MEDLINE
[do] DOI:10.1007/s00221-017-4875-x


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[PMID]:27956062
[Au] Autor:Iigaya K; Okazaki S; Minoura Y; Onimaru H
[Ad] Endereço:Department of Physiology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; Department of Internal Medicine, Hiratsuka City Hospital, 1-19-1 Minamihara, Hiratsuka City, Kanagawa 254-0065, Japan.
[Ti] Título:Interaction between novel oscillation within the ventromedial hypothalamus and the sympathetic nervous system.
[So] Source:Neuroscience;343:213-221, 2017 Feb 20.
[Is] ISSN:1873-7544
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ventromedial hypothalamus (VMH) is known to play an important role in feeding behavior and the control of sympathetic nerve activity (SNA). We report the identification of novel neuron groups that showed oscillations on both sides of the VMH in hypothalamus slice preparations from juvenile rats of postnatal days 5-14. We detected spontaneous rhythmic burst activity with a frequency of around 0.06Hz typically in the dorsolateral region of the VMH (i.e., VMH oscillation) using optical recordings (voltage and calcium imaging), field potential recordings and intracellular membrane potential recordings. The oscillation was also confirmed after isolation of the VMH from other hypothalamic structures. The frequency of oscillation was increased by lowering the glucose concentration of the superfusate. To evaluate the relation between VMH oscillation and SNA, we simultaneously recorded VMH oscillation, SNA from the thoracic sympathetic nerve trunk and phrenic nerve discharge (Phr) in the decerebrate and arterially perfused in situ preparation from juvenile rats of postnatal days 5-11. Power spectral analysis in the arterially perfused in situ rat preparation revealed similar peak values to those of slice preparations within the low-frequency range between the VMH oscillation and sympathetic nerve trunk activity. In addition, we analyzed cross-correlations between the VMH, SNA and Phr. The results revealed that a predominant positive correlation of the VMH activity with the SNA existed with an average time lag of 2.4s, suggesting the presence of functional couplings between the VMH and SNA (and respiratory center) in the lower brainstem and spinal cord. We hypothesize that the VMH oscillation might be involved in low-frequency modulation of the SNA.
[Mh] Termos MeSH primário: Hipotálamo Médio/fisiologia
Periodicidade
Sistema Nervoso Simpático/fisiologia
[Mh] Termos MeSH secundário: Potenciais de Ação
Animais
Cálcio/metabolismo
Estado de Descerebração
Glucose/metabolismo
Microeletrodos
Ratos Wistar
Técnicas de Cultura de Tecidos
Imagens com Corantes Sensíveis à Voltagem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
IY9XDZ35W2 (Glucose); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171108
[Lr] Data última revisão:
171108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161214
[St] Status:MEDLINE


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[PMID]:27940505
[Au] Autor:Kawai Y; DeMonbrun AG; Chambers RS; Nolan DA; Dolcourt BA; Malas NM; Quasney MW
[Ad] Endereço:Divisions of Pediatric Critical Care Medicine and kawai.yu@mayo.edu.
[Ti] Título:A Previously Healthy Adolescent With Acute Encephalopathy and Decorticate Posturing.
[So] Source:Pediatrics;139(1), 2017 Jan.
[Is] ISSN:1098-4275
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A 14-year-old previously healthy female was transferred from a local emergency department after being found unresponsive at home. Parental questioning revealed she had fever and pharyngitis 2 weeks before presentation. Past mental health history was negative, including concern for past or present suicidal ideation/attempts, suspected substance use, or toxic ingestion. In the emergency department, she was orotracheally intubated due to a Glasgow Coma Scale of 3. She was hemodynamically stable and euglycemic. Electrocardiogram showed sinus tachycardia. She underwent a noncontrast head computed tomography that was normal and subsequently underwent a lumbar puncture. She had a seizure and was given a loading dose of diazepam and fosphenytoin that led to cessation of extremity movements. She was subsequently transferred to the PICU for additional evaluation. Initial examination without sedation or analgesia demonstrated dilated and minimally responsive pupils, intermittent decorticate posturing, and bilateral lower extremity rigidity and clonus, consistent with a Glasgow Coma Scale of 5. Serum studies were unremarkable with the exception of mild leukocytosis. Chest radiograph only showed atelectasis. She was empirically started on antibiotics to cover for meningitis pending final cerebral spinal fluid test results. The pediatric neurology team was consulted for EEG monitoring, and the patient was eventually sent for computed tomography angiogram and magnetic resonance angiogram/venogram. We will review diagnostic evaluation and management of an adolescent patient with acute encephalopathy with decorticate posturing of unclear etiology.
[Mh] Termos MeSH primário: Encefalopatia Aguda Febril/induzido quimicamente
Encefalopatia Aguda Febril/etiologia
Encefalopatia Aguda Febril/terapia
Amitriptilina/análogos & derivados
Bupropiona/toxicidade
Estado de Descerebração/induzido quimicamente
Estado de Descerebração/etiologia
Síndrome da Serotonina/diagnóstico
Tentativa de Suicídio
Cloridrato de Venlafaxina/toxicidade
[Mh] Termos MeSH secundário: Encefalopatia Aguda Febril/diagnóstico por imagem
Adolescente
Amitriptilina/toxicidade
Encéfalo/diagnóstico por imagem
Estado de Descerebração/diagnóstico por imagem
Diagnóstico Diferencial
Serviço Hospitalar de Emergência
Feminino
Escala de Coma de Glasgow
Seres Humanos
Unidades de Terapia Intensiva Pediátrica
Comunicação Interdisciplinar
Colaboração Intersetorial
Angiografia por Ressonância Magnética
Imagem por Ressonância Magnética
Automedicação
Tentativa de Suicídio/prevenção & controle
Tomografia Computadorizada por Raios X
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
01ZG3TPX31 (Bupropion); 1806D8D52K (Amitriptyline); 69O5WQQ5TI (cyclobenzaprine); 7D7RX5A8MO (Venlafaxine Hydrochloride)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:161213
[St] Status:MEDLINE


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[PMID]:27702647
[Au] Autor:Zelenin PV; Lyalka VF; Orlovsky GN; Deliagina TG
[Ad] Endereço:Department of Neuroscience, Karolinska Institute, SE-17177 Stockholm, Sweden.
[Ti] Título:Effect of acute lateral hemisection of the spinal cord on spinal neurons of postural networks.
[So] Source:Neuroscience;339:235-253, 2016 Dec 17.
[Is] ISSN:1873-7544
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In quadrupeds, acute lateral hemisection of the spinal cord (LHS) severely impairs postural functions, which recover over time. Postural limb reflexes (PLRs) represent a substantial component of postural corrections in intact animals. The aim of the present study was to characterize the effects of acute LHS on two populations of spinal neurons (F and E) mediating PLRs. For this purpose, in decerebrate rabbits, responses of individual neurons from L5 to stimulation causing PLRs were recorded before and during reversible LHS (caused by temporal cold block of signal transmission in lateral spinal pathways at L1), as well as after acute surgical LHS at L1. Results obtained after Sur-LHS were compared to control data obtained in our previous study. We found that acute LHS caused disappearance of PLRs on the affected side. It also changed a proportion of different types of neurons on that side. A significant decrease and increase in the proportion of F- and non-modulated neurons, respectively, was found. LHS caused a significant decrease in most parameters of activity in F-neurons located in the ventral horn on the lesioned side and in E-neurons of the dorsal horn on both sides. These changes were caused by a significant decrease in the efficacy of posture-related sensory input from the ipsilateral limb to F-neurons, and from the contralateral limb to both F- and E-neurons. These distortions in operation of postural networks underlie the impairment of postural control after acute LHS, and represent a starting point for the subsequent recovery of postural functions.
[Mh] Termos MeSH primário: Lateralidade Funcional/fisiologia
Neurônios/fisiologia
Equilíbrio Postural/fisiologia
Traumatismos da Medula Espinal/fisiopatologia
Medula Espinal/fisiopatologia
[Mh] Termos MeSH secundário: Animais
Temperatura Baixa
Estado de Descerebração
Substância Cinzenta/fisiopatologia
Microeletrodos
Músculo Esquelético/fisiopatologia
Vias Neurais/fisiopatologia
Coelhos
Reflexo/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161105
[St] Status:MEDLINE


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[PMID]:27410926
[Au] Autor:Fenves AZ; Schaefer PW; Luther J; Pierce VM
[Ad] Endereço:From the Departments of Medicine (A.Z.F., J.L.), Radiology (P.W.S.), and Pathology (V.M.P.), Massachusetts General Hospital, and the Departments of Medicine (A.Z.F., J.L.), Radiology (P.W.S.), and Pathology (V.M.P.), Harvard Medical School - both in Boston.
[Ti] Título:CASE RECORDS of the MASSACHUSETTS GENERAL HOSPITAL. Case 21-2016. A 32-Year-Old Man in an Unresponsive State.
[So] Source:N Engl J Med;375(2):163-71, 2016 Jul 14.
[Is] ISSN:1533-4406
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Encéfalo/patologia
Encefalopatia Hepática/etiologia
Hepatite B/diagnóstico
Falência Hepática Aguda/diagnóstico
[Mh] Termos MeSH secundário: Adulto
Estado de Descerebração/etiologia
Diagnóstico Diferencial
Evolução Fatal
Vesícula Biliar/diagnóstico por imagem
Vesícula Biliar/patologia
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[Pt] Tipo de publicação:CASE REPORTS; CLINICAL CONFERENCE; JOURNAL ARTICLE
[Em] Mês de entrada:1607
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:160714
[St] Status:MEDLINE
[do] DOI:10.1056/NEJMcpc1600838


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[PMID]:27288057
[Au] Autor:Ghali MG; Marchenko V
[Ad] Endereço:Department of Neurobiology & Anatomy, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, PA 19129, USA. Electronic address: mgg26@drexel.edu.
[Ti] Título:Effects of vagotomy on hypoglossal and phrenic responses to hypercapnia in the decerebrate rat.
[So] Source:Respir Physiol Neurobiol;232:13-21, 2016 Oct.
[Is] ISSN:1878-1519
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Hypercapnia characterizes a variety of physiological and pathological states and must be compensated effectively by the respiratory, cardiovascular, renal, and intra- and extracellular pH buffering systems to maintain homeostasis. Several studies have examined the respiratory response to hypercapnia, but contemporaneous changes in respiratory frequency and tidal volume prevent investigating the pure influence on respiratory amplitude. Therefore, we sought to test the effect of hypercapnia on hypoglossal (XII) and phrenic nerve (PN) inspiratory (Insp) and XII pre-inspiratory (pre-I) activities in vagus-intact and vagus-denervated animals. Experiments were performed on six artificially-ventilated unanesthetized pre-collicular decerebrate Sprague-Dawley adult male rats. Vagotomy under normocapnic conditions effected the consistent appearance of significant XII pre-I and a greater increase in XII than PN Insp amplitude. In the vagus-intact state, administration of a hypercapnic (5% CO2, 95% O2) gas mixture resulted in a greater increase in XII than PN Insp activity. In the vagotomized state, hypercapnia caused a drastic increase in XII pre-I and significant non-differential increases in both XII and PN Insp activity. The increase in XII pre-I was significantly greater than hypercapnia-induced increases in XII and PN Insp discharges. Following vagotomy, duration and amplitude of XII pre-I are potently modulated by CO2 tension. Based on our results, we conclude that vagal afferents exert differential inhibition of PN Insp and XII pre-I/Insp motor outputs. The role of vagal control in orchestration and optimization of respiratory response to hypercapnia is discussed.
[Mh] Termos MeSH primário: Estado de Descerebração
Hipercapnia/fisiopatologia
Nervo Hipoglosso/fisiopatologia
Nervo Frênico/fisiopatologia
Vagotomia
[Mh] Termos MeSH secundário: Potenciais de Ação/fisiologia
Animais
Pressão Sanguínea/fisiologia
Masculino
Ratos
Ratos Sprague-Dawley
Taxa Respiratória/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160612
[St] Status:MEDLINE



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