Changes in heart period during endodontic treatment

Background: Tooh extraction was demonstrated to increase sympathetic modulation of the heart, however, it is not understood the effects of endodontic treatment on cardiac autonomic regulation. We evaluated heart rate variability (HRV) during endodontic treatment. Method: 50 male and female patients aged between 18 and 40 years old and diagnosed with irreversible pulpitis or pulp necrosis of the lower molars with indication of gender endodontic treatment were analyzed. HRV was analyzed in the time (SDNN, RMSSD, pNN50) and frequency (LF, HF and LF/HF ratio) domains recorded in the first session of root canal treatment. The indices were analyzed in the following periods: T1) ten minutes before the endodontic treatment, T2) ten minutes after the administration of anesthesia before endodontic treatment, T3) during the entire period of endodontic treatment and T4) thirty minutes after the end of the endodontic treatment. Results: The SDNN, RMSSD and pNN50 indices increased at T2 compared to T1, the pNN50 and RMSSD indices increased at T3 and T4 compared to T2. The LF in normalized units increased at T4 compared to T2 and in absolute units it was increased at T4 compared to T1. The HF in normalized units was reduced at T4 compared to T2 and in absolute units was reduced at T1, T3 and T4 compared to T2. The LF/HF ratio was higher at T4 compared to T2. Conclusion: The global modulation of heart increases after local anesthesia and vagal tone reduce during surgery procedures and after the surgical procedures.

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

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

Variabilidade da frequência cardíaca como recurso em fisioterapia: análise de periódicos nacionais

INTRODUCTION: The autonomic nervous system (ANS) could be investigated in a noninvasive way by the heart rate variability analysis (HRV) which has contributed to several health areas such as physiotherapy. OBJECTIVE: To gather information regarding the use of HRV on physiotherapy aims at providing an update of the findings for the area on journals of national circulation. MATERIALS AND METHODS: The journals of national circulation classified as greater than B2 or B2 and with free access and complete texts in some internet sites were searched on 21 area WebQualis resulting on selection of Revista Brasileira de Fisioterapia, Fisioterapia e Pesquisa and Fisioterapia em Movimento using the keywords: autonomic nervous system, sympathetic nervous system, physiotherapy and heart rate variability. RESULTS: The search resulted in 19 articles being 17 clinical trials and two case reports. CONCLUSION: The HRV has been used as a resource of interventions evaluation, as pathological conditions common to clinical practice investigation and to physiological conditions interpretation in physiotherapy. The HRV is principally used to the cardiorespiratory specialty of physiotherapy.

Mensuração e análise do ph salivar em pacientes com hiperidrose submetidos a cirurgia de simpatectomia videotoracoscópica

The study was performed to verify if there are changes in salivary pH in patients with hyperhidrosis who were treated by Videothoracoscopic Sympathectomy. Twelve patients underwent sympathectomy with clamping the sympathetic chain along the vertebrae T2, T3 and T4, under inhalation and intravenous general anesthesia and with drainage of pneumothorax through probe N° 16. These patients had their saliva collected 1 day before and 7 days after surgery for measurement of pH by the colorimetric method with indicator paper. All patients showed no sign or symptom of hyperhidrosis in the immediate postoperative period, which demonstrates the success of sympathetic denervation on these levels. No patient had compensatory sweating and there was no post-operatively surgical complication. No drug or substance has been administered to patients for the study. The pH results obtained were analyzed using test ´´t´´ Student. Although the average pH in samples obtained after surgery was lower than the preoperative, the test revealed no statistically significant difference (p = 0.181). It is concluded that sympathectomy, an excellent therapeutic and definitive method for hyperhidrosis, does not alter the salivary pH, and so, did not influence the cariogenic process

Investigação da participação de adrenoceptores α1A e α1D na contração da cauda de epididímo de rato e sua androgênica e estrogênica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O Wortmannin reverte a hiporreatividade de aortas à fenilefrina associada à fase final da prenhez de ratas espontaneamente hipertensas (SHR)

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

Peripheral chemoreceptors and cardiorespiratory coupling: a link to sympatho-excitation

Chronic intermittent hypoxia (CIH) has been identified as a relevant risk factor for the development of enhanced sympathetic outflow and arterial hypertension. Several studies have highlighted the importance of peripheral chemoreceptors for the cardiovascular changes elicited by CIH. However, the effects of CIH on the central mechanisms regulating sympathetic outflow are not fully elucidated. Our research group has explored the hypothesis that the enhanced sympathetic drive following CIH exposure is, at least in part, dependent on alterations in the respiratory network and its interaction with the sympathetic nervous system. In this report, I discuss the changes in the discharge profile of baseline sympathetic activity in rats exposed to CIH, their association with the generation of active expiration and the interactions between expiratory and sympathetic neurones after CIH conditioning. Together, these findings are consistent with the theory that mechanisms of central respiratory–sympathetic coupling are a novel factor in the development of neurogenic hypertension.

Sympatho-excitation during chemoreflex active expiration is mediated by L-glutamate in the RVLM/Bötzinger complex of rats

The involvement of glutamatergic neurotransmission in the rostral ventrolateral medulla/Bötzinger/pre-Bötzinger complexes (RVLM/BötC/pre-BötC) on the respiratory modulation of sympathoexcitatory response to peripheral chemoreflex activation (chemoreflex) was evaluated in the working heart-brain stem preparation of juvenile rats. We identified different types of baro- and chemosensitive presympathetic and respiratory neurons intermingled within the RVLM/BötC/pre-BötC. Bilateral microinjections of kynurenic acid (KYN) into the rostral aspect of RVLM (RVLM/BötC) produced an additional increase in frequency of the phrenic nerve (PN: 0.38 ± 0.02 vs. 1 ± 0.08 Hz; P < 0.05; n = 18) and hypoglossal (HN) inspiratory response (41 ± 2 vs. 82 ± 2%; P < 0.05; n = 8), but decreased postinspiratory (35 ± 3 vs. 12 ± 2%; P < 0.05) and late-expiratory (24 ± 4 vs. 2 ±1%; P < 0.05; n = 5) abdominal (AbN) responses to chemoreflex. Likewise, expiratory vagal (cVN; 67 ± 6 vs. 40 ± 2%; P < 0.05; n = 5) and expiratory component of sympathoexcitatory (77 ± 8 vs. 26 ± 5%; P < 0.05; n = 18) responses to chemoreflex were reduced after KYN microinjections into RVLM/BötC. KYN microinjected into the caudal aspect of the RVLM (RVLM/pre-BötC; n = 16) abolished inspiratory responses [PN (n = 16) and HN (n = 6)], and no changes in magnitude of sympathoexcitatory (n = 16) and expiratory (AbN and cVN; n = 10) responses to chemoreflex, producing similar and phase-locked vagal, abdominal, and sympathetic responses. We conclude that in relation to chemoreflex activation 1) ionotropic glutamate receptors in RVLM/BötC and RVLM/pre-BötC are pivotal to expiratory and inspiratory responses, respectively; and 2) activation of ionotropic glutamate receptors in RVLM/BötC is essential to the coupling of active expiration and sympathoexcitatory response.

Control of respiratory and cardiovascular functions by leptin

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

Electrophysiological properties of rostral ventrolateral medulla presympathetic neurons modulated by the respiratory network in rats

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

Dysautonomias in parkinson's disease: cardiovascular changes and autonomic modulation in conscious rats after infusion of bilateral 6-OHDA in substantia nigra

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Immediate and long-term effects of psychological stress during adolescence in cardiovascular function: comparison of homotypic vs heterotypic stress regimens

Adolescence has been proposed as an ontogenic period of vulnerability to stress. Nevertheless, the impact of stressful events during adolescence in cardiovascular activity is poorly understood. Therefore, the purpose of this study was to investigate the immediate and long-lasting effects of exposure to stressful events during adolescence in cardiovascular function of rats. To this end, we compared the impact of 10-days exposure to two chronic stress protocols: the repeated restraint stress (RRS, homotypic) and chronic variable stress (CVS, heterotypic). Independent groups of animals were tested 24 h (immediate) or three weeks (long-lasting) following completion of stress period. Exposure to CVS, but not RRS, during adolescence increased basal HR values without affecting arterial pressure, which was followed by augmented power of oscillatory component at low frequency (sympathetic-related) of the pulse interval (PI). RRS enhanced variance of the PI with an increase in the power of both low and high (parasympathetic-related) frequency components. RRS also increased the baroreflex gain. Neither RRS nor CVS affected systolic arterial pressure variability. The RRS-evoked changes in PI variability were long-lasting and persisted into adulthood while all alterations evoked by the CVS were reversed in adulthood. These findings indicate a stress type-specific influence in immediate and long-term effects of stress during adolescence in cardiovascular function. While immediate changes in cardiovascular function were mainly observed following CVS, long-lasting autonomic consequences in adulthood were observed only in animals exposed to RRS during adolescence.

Stress vulnerability during adolescence

Objective: This study investigated the physiological and somatic changes evoked by daily exposure to the same type of stressor (homotypic) or different aversive stressor stimuli (heterotypic) in adolescent and adult rats, with a focus on cardiovascular function. The long-term effects of stress exposure during adolescence were also investigated longitudinally. Methods: Male Wistar rats were exposed to repeated restraint stress (RRS, homotypic) or chronic variable stress (CVS, heterotypic). Results: Adrenal hypertrophy, thymus involution, and elevated plasma glucocorticoid were observed only in adolescent animals, whereas reduction in body weight was caused by both stress regimens in adults. CVS increased mean arterial pressure (adolescent: p = .001; adult: p = .005) and heart rate (HR; adolescent: p = .020; adult: p = .011) regardless of the age, whereas RRS increased blood pressure selectively in adults (p = .001). Rest tachycardia evoked by CVS was associated with increased cardiac sympathetic activity in adults, whereas a decreased cardiac parasympathetic activity was observed in adolescent animals. Changes in cardiovascular function and cardiac autonomic activity evoked by both CVS and RRS were followed by alterations in baroreflex activity and vascular reactivity to vasoconstrictor and vasodilator agents in adolescent adult animals. Except for the circulating glucocorticoid change, all alterations observed during adolescence were reversed in adulthood. Conclusions: These findings suggest a stress vulnerability of adolescents to somatic and neuroendocrine effects regardless of stress regimen. Our results indicated an age-stress type-specific influence in stress-evoked cardiovascular/autonomic changes. Data suggest minimal consequences in adulthood of stress during adolescence.

Respostas da frequência cardíaca ao teste de 1RM e da modulação autonômica da frequência cardíaca no período de recuperação em indivíduos com fatores de risco para doenças cardiovasculares

Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC

Papel das espécies reativas de oxigênio na hiporreatividade de aortas à fenilefrina observada no final da prenhez de Ratas Espontaneamente Hipertensas (SHR)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)