In patients with obstructive sleep apnea (OSA) during obstructive events, episodes of hypoxia and hypercapnia may modulate the autonomic nervous system (ANS) by increasing sympathetic tone and irritability, which contributes to sympathovagal imbalance and ultimately dysautonomia. Because OSA can alter ANS function through biochemical changes, we can assume that heart rate variability (HRV) will be altered in patients with OSA. Most studies show that in both the time and frequency domains, patients with OSA have higher sympathetic components and lower parasympathetic dominance than healthy controls. These results confirm autonomic dysfunction in these patients, but also provide new therapeutic directions. Respiratory methods that modulate ANS, e.g., cardiorespiratory biofeedback, could be beneficial for these patients. Heart rate variability assessment can be used as a tool to evaluate the effectiveness of OSA treatment due to its association with autonomic impairment.
The cardiovascular system is primarily controlled by the autonomic nervous system, and any changes in sympathetic or parasympathetic activity also have an impact on myocardial activity. Heart rate variability (HRV) is a readily available metric used to assess heart rate control by the autonomic nervous system. HRV can provide information about neural (parasympathetic, sympathetic, reflex) and humoral (hormones, thermoregulation) control of myocardial activity. Because there are no relevant reference values for HRV parameters in rats in the scientific literature, all experimental results are only interpreted on the basis of changes from currently measured control or baseline HRV values, which are, however, significantly different in individual studies. Considering the significant variability of published HRV data, the present study focused primarily on comparing control or baseline HRV values under different conditions in in vivo experiments involving rats. The aim of the study was therefore to assess whether there are differences in the starting values before the experiment itself.
NEW FINDINGS: What is the topic of this review? Changes in heart rate variability in rats with sex differences and the use of different anaesthesia during light-dark cycles. What advances does it highlight? The review highlights and discusses synthesized current results in order to advance knowledge and understanding of sex differences with an emphasis on changes in the autonomic nervous system determined by heart rate variability. ABSTRACT: Heart rate variability (HRV) is commonly used in experimental studies to assess sympathetic and parasympathetic activities. The belief that HRV in rodents reflects similar cardiovascular regulations in humans is supported by evidence, and HRV in rats appears to be at least analogous to that in humans, although the degree of influence of the parasympathetic division of the autonomic nervous system (ANS) may be greater in rats than in humans. Experimental studies are based on control or baseline values, on the basis of which the change in ANS activity after a given experimental intervention is assessed, but it is known that the ANS in rats is very sensitive to various stress interventions, such as the manipulation itself, and ANS activity can also differ depending on sex, the time of measurement, and whether the animals are under general anaesthesia. Thus, for correct assessment, changes in ANS activity and their relationship to the observed parameter should be based on whether ANS activity does or does not change but also to what extent the activity is already changed at the start of the experiment. Since rats are considered to be the most suitable model animal for basic cardiovascular research, in this review we point out existing differences in individual HRV frequency parameters at the start of experiments (control, baseline values), taking into account sex in relation to time of measurement and anaesthesia.
- MeSH
- autonomní nervový systém * fyziologie MeSH
- celková anestezie MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- pohlavní dimorfismus * MeSH
- srdce MeSH
- srdeční frekvence fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
In in vivo cardiovascular or toxicological studies involving rat models, changes in selected electrocardiographic (ECG) parameters are monitored after various interventions to assess the origin and development of heart rhythm disorders. Each ECG parameter has diagnostic significance; as such, commonly evaluated ECG parameters, including heart rate, PR interval, P wave duration, P wave amplitude, QRS complex, QT and QTc interval duration, R wave and T wave amplitude, of rats under various types of general anesthesia were the focus of this study. Studies that performed in vivo cardiovascular or toxicological experiments in rats were retrieved from a search of the Web of Science database for articles published mainly between 2000 and 2021. In total, the search retrieved 123 articles. ECG parameters that were reported as baseline or control values were summarized and averages with ranges were calculated. It is important to be cautious when interpreting results and, in discussions addressing the mechanisms underlying a given type of arrhythmia, acknowledge that initial ECG parameters may already be affected to some extent by the general anesthesia as well as by sex and the time of day the experiments were performed.
The aim of study was to review the status of arterial pH, pO(2) and pCO(2) under general anesthesias in dependence on the light-dark (LD) cycle in spontaneously breathing rats. The experiments were performed using three- to four-month-old pentobarbital(P)-, ketamine/xylazine(K/X)- and zoletil(Z)-anesthetized female Wistar rats after a four-week adaptation to an LD cycle (12 h light:12 h dark). The animals were divided into three experimental groups according to the anesthetic agent used: P (light n=11; dark n=8); K/X (light n=13; dark n=11); and Z (light n=18; dark n=26). pH and blood gases from arterial blood were analyzed. In P anesthesia, LD differences in pH, pO(2), and pCO(2) were eliminated. In K/X anesthesia, parameters showed significant LD differences. In Z anesthesia, LD differences were detected for pH and pO(2) only. Acidosis, hypoxia, and hypercapnia have been reported for all types of anesthesia during the light period. In the dark period, except for P anesthesia, the environment was more stable and values fluctuated within normal ranges. From a chronobiological perspective, P anesthesia was not the most appropriate type of anesthesia in these rat experiments. It eliminated LD differences, and also produced a more acidic environment and more pronounced hypercapnia than K/X and Z anesthesias.
- MeSH
- analýza krevních plynů metody MeSH
- anestetika celková škodlivé účinky krev farmakologie MeSH
- celková anestezie * škodlivé účinky trendy MeSH
- chronobiologické jevy účinky léků fyziologie MeSH
- fixní kombinace léků MeSH
- hyperkapnie krev chemicky indukované MeSH
- hypoxie krev chemicky indukované MeSH
- ketamin škodlivé účinky farmakologie MeSH
- krysa rodu rattus MeSH
- pentobarbital škodlivé účinky farmakologie MeSH
- potkani Wistar MeSH
- tiletamin škodlivé účinky farmakologie MeSH
- zolazepam škodlivé účinky farmakologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Klíčová slova
- zoletilová anestezie,
- MeSH
- acidobazická rovnováha MeSH
- anxiolytika MeSH
- chronobiologické jevy * MeSH
- elektrokardiografie MeSH
- interpretace statistických dat MeSH
- modely u zvířat MeSH
- potkani Wistar MeSH
- tělesná teplota MeSH
- tiletamin terapeutické užití MeSH
- zolazepam terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- MeSH
- acidobazická rovnováha MeSH
- anestetika disociativní MeSH
- autonomní nervový systém účinky léků MeSH
- celková anestezie * MeSH
- chronobiologie (obor) MeSH
- cirkadiánní rytmus MeSH
- elektrofyziologie MeSH
- ketamin * aplikace a dávkování terapeutické užití MeSH
- modely u zvířat MeSH
- potkani Wistar MeSH
- srdeční frekvence účinky léků MeSH
- xylazin * aplikace a dávkování terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- MeSH
- acidobazická rovnováha MeSH
- adjuvancia anestetická MeSH
- celková anestezie * MeSH
- chronobiologie (obor) MeSH
- cirkadiánní rytmus MeSH
- elektrofyziologie MeSH
- modely u zvířat MeSH
- myokard MeSH
- pentobarbital * aplikace a dávkování terapeutické užití MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- abstrakt z konference MeSH
INTRODUCTION: Surgical intervention in obesity is today the most effective treatment method in high level obesity management. Bariatric interventions not only ensure body weight reduction, but may influence dietary habits. AIM: To assess changes in adipose hormones and dietary habits in obese patients after sleeve gastrectomy. MATERIAL AND METHODS: The study set comprised 37 subjects (29 females and 8 males) 24 to 68 years old with body mass index 43.0 ±4.9 kg/m(2). Pre-operative examination included baseline measurements of body composition. Dietary habits and intake frequency were monitored by a questionnaire method. Follow-up examinations were carried out in a scope identical to the pre-operative examination, 6 and 12 months after surgery, respectively. RESULTS: The average patient weight loss 12 months after surgery was 31.7 kg. Excess weight loss was 55.2 ±20.6%. Patients reported reduced appetite (p < 0.001), increasingly regular food intake (p < 0.001), intake of more meal portions per day (p = 0.003) and a decrease in consuming the largest portions during the afternoon and evening (p = 0.030). Plasma levels of fasting glucose, leptin and ghrelin significantly decreased (p = 0.006; p = 0.0.043); in contrast, the level of adiponectin significantly increased (p < 0.001). CONCLUSIONS: Sleeve gastrectomy and follow-up nutritional therapy resulted in a significant body weight reduction within 1 year after surgery. An improvement of certain dietary habits in patients was registered. At 12 months after surgery, there were no statistically significant differences in decreases in ghrelin and leptin concentrations between patients without changed appetite and those reporting decreased appetite.
- Publikační typ
- časopisecké články MeSH
