Neuropeptides in the posterodorsal medial amygdala modulate central cardiovascular reflex responses in awake male rats

The rat posterodorsal medial amygdala (MePD) links emotionally charged sensory stimuli to social behavior, and is part of the supramedullary control of the cardiovascular system. We studied the effects of microinjections of neuroactive peptides markedly found in the MePD, namely oxytocin (OT, 10 ng and 25 pg; n=6/group), somatostatin (SST, 1 and 0.05 mu M; n=8 and 5, respectively), and angiotensin II (Ang II, 50 pmol and 50 fmol; n=7/group), on basal cardiovascular activity and on baroreflex- and chemoreflex-mediated responses in awake adult male rats. Power spectral and symbolic analyses were applied to pulse interval and systolic arterial pressure series to identify centrally mediated sympathetic/parasympathetic components in the heart rate variability (HRV) and arterial pressure variability (APV). No microinjected substance affected basal parameters. On the other hand, compared with the control data (saline, 0.3 mu L; n=7), OT (10 ng) decreased mean AP (MAP(50)) after baroreflex stimulation and increased both the mean AP response after chemoreflex activation and the high-frequency component of the HRV. OT (25 pg) increased overall HRV but did not affect any parameter of the symbolic analysis. SST (1 mu M) decreased MAP(50), and SST (0.05 mu M) enhanced the sympathovagal cardiac index. Both doses of SST increased HRV and its low-frequency component. Ang II (50 pmol) increased HRV and reduced the two unlike variations pattern of the symbolic analysis (P<0.05 in all cases). These results demonstrate neuropeptidergic actions in the MePD for both the increase in the range of the cardiovascular reflex responses and the involvement of the central sympathetic and parasympathetic systems on HRV and APV.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPERGSUniv Fed Ciencias Saude Porto Alegre, Dept Ciencias Basicas Saude Fisiol, Porto Alegre, RS, BrazilUniv Fed Rio Grande do Sul, Programa Posgrad Neurociencias, Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Inst Ciencia & Tecnol, Sao Jose Dos Campos, SP, BrazilUniv Fed Ciencias Saude Porto Alegre, Dept Fisioterapia, Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Inst Ciencia & Tecnol, Sao Jose Dos Campos, SP, BrazilCNPq: 501041/2012-5FAPERGS: 1016957Web of Scienc

Cardiovascular control in experimental diabetes

Several studies have reported impairment in cardiovascular function and control in diabetes. The studies cited in this review were carried out from a few days up to 3 months after streptozotocin administration and were concerned with the control of the circulation. We observed that early changes (5 days) in blood pressure control by different peripheral receptors were maintained for several months. Moreover, the impairment of reflex responses observed after baroreceptor and chemoreceptor stimulation was probably related to changes in the efferent limb of the reflex arc (sympathetic and parasympathetic), but changes also in the central nervous system could not be excluded. Changes in renal sympathetic nerve activity during volume expansion were blunted in streptozotocin-treated rats, indicating an adaptive natriuretic and diuretic response in the diabetic state. The improvement of diabetic cardiovascular dysfunction induced by exercise training seems to be related to changes in the autonomic nervous system. Complementary studies about the complex interaction between circulation control systems are clearly needed to adequately address the management of pathophysiological changes associated with diabetes.Universidade de Santo Amaro UNIPESQ Laboratório de CardiovascularUniversidade Federal do Rio Grande do Sul Instituto de Ciências Básicas da Saúde Departamento de FisiologiaInstituto de Cardiologia do Rio Grande do Sul Fundação Universitária de CardiologiaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de NefrologiaUniversidade de São Paulo Faculdade de Medicina Hospital das ClínicasPontifícia Universidade Católica do Rio Grande do Sul FAENFI Curso de FisioterapiaUNIFESP, EPM, Depto. de NefrologiaSciEL

Acute Strenuous Exercise Induces an Imbalance on Histone H4 Acetylation/Histone Deacetylase 2 and Increases the Proinflammatory Profile of PBMC of Obese Individuals

This study evaluated the response of global histone H4 acetylation (H4ac), histone deacetylase 2 (HDAC2) activity, as well as the production of proinflammatory cytokines and monocyte phenotypes of lean and obese males after exercise. Ten lean and ten obese sedentary men were submitted to one session of strenuous exercise, and peripheral blood mononuclear cells (PBMC) were stimulated in vitro with lipopolysaccharide (LPS). Global H4ac levels, HDAC2 activity in PBMC, and IL-6, IL-8, and TNF-α production were analyzed. Monocyte phenotype was determined in accordance with the expression of CD14 and CD16. At rest, obese individuals presented higher frequency of proinflammatory CD14+CD16+ monocytes. LPS induced a significant augment in global H4ac and in the production of IL-6, IL-8, and TNF-α mainly in obese individuals. After exercise, the increased production of IL-8 and TNF-α and peripheral frequency of CD14+CD16+ were observed in both groups. In addition, exercise also induced a significant hyperacetylation of histone H4 and decreased HDAC2 activity in both nonstimulated and LPS-stimulated PBMC of obese individuals. Our data indicate that the obesity impacts on H4ac levels and that strenuous exercise leads to an enhanced chronic low-grade inflammation profile in obesity via an imbalance on H4ac/HDAC2

Only low intensity of aerobic exercise improves respiratory compliance in pulmonary hypertensive rats

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Pau Casals y el uso de la agógica. Un estudio analítico a partir del Prélude BWV 1007 y la Sarabande BWV 1011 de las Suites para violoncello solo de J.S. Bach.

Con más de un siglo de música grabada y junto con las herramientas computacionales de análisis del sonido que se han desarrollado y que están en constante actualización, las investigaciones sobre grabaciones sonoras están creciendo de manera exponencial. Este material sirve para conocer el proceso interpretativo de un artista, especialmente cuando el músico a estudio ya ha fallecido, como es el caso de Pau Casals. Además de su patrimonio y biografías, de Casals se conserva una importante cantidad de grabaciones sonoras, entrevistas y clases magistrales. Casals fue una de las figuras más importantes de la historia de la interpretación del violoncello. Sus aportaciones técnicas al instrumento, su concepción sobre el estilo interpretativo y la elección del repertorio que tocaba y grababa son fundamentales para comprender la historia de la interpretación musical de la primera mitad del Siglo XX. En el estilo de Casals destacaba su uso del rubato como elemento expresivo, un magistral sentido de la proporcionalidad en el tiempo y en el espacio. En las obras donde hay regularidad de los valores rítmicos, el intérprete cobra más importancia porque respetando el texto escrito, debe proponer variedad para no caer en Ja monotonía. En las Seis Suites para violoncello solo de J.S. Bach, el ejecutante se enfrenta en solitario a tomar decisiones interpretativas donde debe administrar la fantasía que reivindicaba Casals, pero con orden. En plena madurez musical, Casals grabó la integral de las Suites a partir de 1936, siendo el primero en registrarlas. Entre los 36 movimientos, en algunos destaca la regularidad de valores rítmicos: en el Prélude de la Primera Suite, de las 654 notas, 651 son semicorcheas. En la Sarabande de la Quinta Suite, de las 108 notas, 100 son corcheas, el doble con las repeticiones de las dos partes de la obra. Ambos movimientos son propicios para estudiar la flexibilidad rítmica en obras con poca cantidad de valores rítmicos. Como se muestra en el análisis y el comentario de esta investigación, Casals logra variedad en la interpretación mediante el uso de la flexibilidad rítmica en la interpretación. Así, en esta tesis se investiga el proceso interpretativo de Casals sobre los dos movimientos. Además, se parte de un proyecto internacional relacionado con la investigación aplicada a la música, dado que el software Sonic Visualiser es utilizado como una herramienta de análisis para obtener datos sobre Pau Casals. Finalmente, el trabajo participa de las nuevas tendencias de investigación en arte o investigación artística en la medida que la propia experiencia como violoncellísta del investigador es utilizada como fuente primaria de conocimiento.Programa Oficial de Doctorado en Desarrollo de las Capacidades Musicales (RD 1393/2007)Musika Gaitasunen Garapeneko Doktoretza Programa Ofiziala (ED 1393/2007