Cardiovascular and autonomic alterations in rats with parkinsonism induced by 6-OHDA and treated with L-DOPA

Evaluate the effects caused by L-DOPA on cardiovascular and autonomic parameters in an animal model of Parkinsonism induced by 6-hydroxydopamine (6-OHDA).Adult male Wistar rats were subjected to bilateral microinfusion of 6-OHDA or saline (sham group) in the substantia nigra, and treated by gavage with L-DOPA or water for 7days after surgery. On the 6th day the rats were subjected to femoral artery catheterization for cardiovascular recording. Mean arterial pressure (MAP) and heart rate (HR) were evaluated at baseline and during head up tilt (HUT) protocol. Spectral analysis of cardiovascular variability was performed using the V2.4 CardioSeries software v2.4. The lesion was quantified by dopamine levels in the striatum.Dopamine levels in the striatum were decreased in 6-OHDA rats (sham: 4.79±0.49ng/mg; 6-OHDA: 1.99±0.68ng/mg) and were not recovered by Prolopa treatment. Baseline values of MAP and HR were not different between groups. HUT induced an increase in MAP and HR (ΔMAP: 17±1mmHg, ΔHR: 39±4bpm) that were attenuated in 6-OHDA and in Prolopa treated animals. At baseline, the systolic arterial pressure (SAP) variance was lower in the 6-OHDA and sham Prolopa groups. Spontaneous baroreflex sensitivity was higher at baseline in the 6-OHDA group as compared to all studied groups.Our data suggest that treatment with Prolopa did not interfere with cardiovascular variables at baseline. However, during HUT, the 6-OHDA and Prolopa control animals presented a lower cardiovascular compensation, suggesting a possible autonomic impairment in Parkinsonism induced by 6-OHDA.

TRPV4 activates autonomic and behavioural warmth-defence responses in Wistar rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Response of cardiac autonomic modulation after a single exposure to musical auditory stimulation

The acute effects after exposure to different styles of music on cardiac autonomic modulation assessed through heart rate variability (HRV) analysis have not yet been well elucidated. We aimed to investigate the recovery response of cardiac autonomic modulation in women after exposure to musical auditory stimulation of different styles. The study was conducted on 30 healthy women aged between 18 years and 30 years. We did not include subjects having previous experience with musical instruments and those who had an affinity for music styles. The volunteers remained at rest for 10 min and were exposed to classical baroque (64-84 dB) and heavy metal (75-84 dB) music for 10 min, and their HRV was evaluated for 30 min after music cessation. We analyzed the following HRV indices: Standard deviation of normal-to-normal (SDNN) intervals, root mean square of successive differences (RMSSD), percentage of normal-to-normal 50 (pNN50), low frequency (LF), high frequency (HF), and LF/HF ratio. SDNN, LF in absolute units (ms (2) ) and normalized (nu), and LF/HF ratio increased while HF index (nu) decreased after exposure to classical baroque music. Regarding the heavy metal music style, it was observed that there were increases in SDNN, RMSSD, pNN50, and LF (ms (2) ) after the musical stimulation. In conclusion, the recovery response of cardiac autonomic modulation after exposure to auditory stimulation with music featured an increased global activity of both systems for the two musical styles, with a cardiac sympathetic modulation for classical baroque music and a cardiac vagal tone for the heavy metal style.

Cardiac autonomic modulation of children with down syndrome

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Analysis of autonomic modulation after an acute session of resistance exercise at different intensities in chronic obstructive pulmonary disease patients

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparison of the Effects of Hydration with Water or Isotonic Solution on the Recovery of Cardiac Autonomic Modulation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Acute auditory stimulation with different styles of music influences cardiac autonomic regulation in men

No clear evidence is available in the literature regarding the acute effect of different styles of music on cardiac autonomic control. The present study aimed to evaluate the acute effects of classical baroque and heavy metal musical auditory stimulation on Heart Rate Variability (HRV) in healthy men. In this study, HRV was analyzed regarding time (SDNN, RMSSD, NN50, and pNN50) and frequency domain (LF, HF, and LF / HF) in 12 healthy men. HRV was recorded at seated rest for 10 minutes. Subsequently, the participants were exposed to classical baroque or heavy metal music for five minutes through an earphone at seated rest. After exposure to the first song, they remained at rest for five minutes and they were again exposed to classical baroque or heavy metal music. The music sequence was random for each individual. Standard statistical methods were used for calculation of means and standard deviations. Besides, ANOVA and Friedman test were used for parametric and non-parametric distributions, respectively. While listening to heavy metal music, SDNN was reduced compared to the baseline (P = 0.023). In addition, the LF index (ms(2) and nu) was reduced during exposure to both heavy metal and classical baroque musical auditory stimulation compared to the control condition (P = 0.010 and P = 0.048, respectively). However, the HF index (ms(2)) was reduced only during auditory stimulation with music heavy metal (P = 0.01). The LF/HF ratio on the other hand decreased during auditory stimulation with classical baroque music (P = 0.019). Acute auditory stimulation with the selected heavy metal musical auditory stimulation decreased the sympathetic and parasympathetic modulation on the heart, while exposure to a selected classical baroque music reduced sympathetic regulation on the heart.

Can geometric indices of heart rate variability predict improvement in autonomic modulation after resistance training in chronic obstructive pulmonary disease?

Chronic obstructive pulmonary disease (COPD) is associated with autonomic dysfunctions that can be evaluated through heart rate variability (HRV). Resistance training promotes improvement in autonomic modulation; however, studies that evaluate this scenario using geometric indices, which include nonlinear evaluation, thus providing more accurate information for physiological interpretation of HRV, are unknown. This study aimed to investigate the influence of resistance training on autonomic modulation, using geometric indices of HRV, and peripheral muscle strength in individuals with COPD. Fourteen volunteers with COPD were submitted to resistance training consisting of 24 sessions lasting 60 min each, with a frequency of three times a week. The intensity was determined as 60% of one maximum repetition and was progressively increased until 80% for the upper and lower limbs. The HRV and dynamometry were performed at two moments, the beginning and the end of the experimental protocol. Significant increases were observed in the RRtri (4·81 ± 1·60 versus 6·55 ± 2·69, P = 0·033), TINN (65·36 ± 35·49 versus 101·07 ± 63·34, P = 0·028), SD1 (7·48 ± 3·17 versus 11·04 ± 6·45, P = 0·038) and SD2 (22·30 ± 8·56 versus 32·92 ± 18·78, P = 0·022) indices after the resistance training. Visual analysis of the Poincare plot demonstrated greater dispersion beat-to-beat and in the long-term interval between consecutive heart beats. Regarding muscle strength, there was a significant increase in the shoulder abduction and knee flexion. In conclusion, geometric indices of HRV can predict improvement in autonomic modulation after resistance training in individuals with COPD; improvement in peripheral muscle strength in patients with COPD was also observed.

Impact of functional training on cardiac autonomic modulation, cardiopulmonary parameters and quality of life in healthy women

Coordenação de Aperfeiçoamentode Pessoal de Nível Superior (CAPES)

Impact of obesity on autonomic modulation, heart rate and blood pressure in obese young people

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Balance and ankle muscle strength predict spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy

The aims of this study were to evaluate aspects of balance, ankle muscle strength and spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy (DPN) and verify whether deficits in spatiotemporal gait parameters were associated with ankle muscle strength and balance performance. Thirty individuals with DPN and 30 control individuals have participated. Spatiotemporal gait parameters were evaluated by measuring the time to walk a set distance during self-selected and maximal walking speeds. Functional mobility and balance performance were assessed using the Functional Reach and the Time Up and Go tests. Ankle isometric muscle strength was assessed with a handheld digital dynamometer. Analyses of variance were employed to verify possible differences between groups and conditions. Multiple linear regression analysis was employed to uncover possible predictors of gait deficits. Gait spatiotemporal, functional mobility, balance performance and ankle muscle strength were affected in individuals with DPN. The Time Up and Go test performance and ankle muscle isometric strength were associated to spatiotemporal gait changes, especially during maximal walking speed condition. Functional mobility and balance performance are damaged in DPN and balance performance and ankle muscle strength can be used to predict spatiotemporal gait parameters in individuals with DPN.

Autonomic control of post-air-breathing tachycardia in Clarias gariepinus (Teleostei: Clariidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The extract of the jellyfish Phyllorhiza punctata promotes neurotoxic effects

Phyllorhiza punctata (P. punctata) is a jellyfish native to the southwestern Pacific. Herewith we present the biochemical and pharmacological characterization of an extract of the tentacles of P. punctata. The tentacles were subjected to three freezethaw cycles, homogenized, ultrafiltered, precipitated, centrifuged and lyophilized to obtain a crude extract (PHY-N). Paralytic shellfish poisoning compounds such as saxitoxin, gonyautoxin-4, tetrodotoxin and brevetoxin-2, as well as several secretory phospholipase A2 were identified. PHY-N was tested on autonomic and somatic neuromuscular preparations. In mouse vas deferens, PHY-N induced phasic contractions that reached a peak of 234 +/- 34.7% of control twitch height, which were blocked with either 100 mu m of phentolamine or 1m m of lidocaine. In mouse corpora cavernosa, PHY-N evoked a relaxation response, which was blocked with either L-NG-Nitroarginine methyl ester (0.5 m m) or 1m m of lidocaine. PHY-N (1, 3 and 10 mu g ml(-1)) induced an increase in tonus of the biventercervicis neuromuscular preparation that was blocked with pre-treatment of galamine (10 mu m). Administration of 6 mg kg(-1) PHY-N intramuscularly produced death in broilers by spastic paralysis. In conclusion, PHY-N induces nerve depolarization and nonspecifically increases neurotransmitter release. Copyright (C) 2011 John Wiley & Sons, Ltd.

Neuropatia paraneoplásica associada ao mastocitoma canino

As síndromes paraneoplásicas compreendem um grupo diverso de alterações clínicas associadas a neoplasias e ocorrem em sítios distantes do tumor primário ou de suas metástases. As neuropatias paraneoplásicas são distúrbios raros em cães, mas representam morbidade significativa e servem como importantes indicadores diagnósticos e prognósticos. O presente trabalho relata a ocorrência de dois casos de neuropatia paraneoplásica em cães com mastocitoma, considerando a apresentação clínica, o diagnóstico e as formas de tratamento utilizadas.

CONTROL of THE CENTRAL CHEMOREFLEX BY A5 NORADRENERGIC NEURONS IN RATS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)