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Švorc P, Grešová S, Švorc P. Heart rate variability in male rats. Physiol Rep 2023; 11:e15827. [PMID: 37735345 PMCID: PMC10514026 DOI: 10.14814/phy2.15827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 09/23/2023] Open
Abstract
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.
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Affiliation(s)
- Pavol Švorc
- Department of Physiology and Pathophysiology, Faculty of MedicineOstrava UniversityOstravaCzech Republic
| | - Soňa Grešová
- Department of Physiology, Faculty of MedicineUniversity PJ SafarikaKosiceSlovak Republic
| | - Pavol Švorc
- Department of Physiology and Pathophysiology, Faculty of MedicineOstrava UniversityOstravaCzech Republic
- Department of Physiology, Faculty of MedicineUniversity PJ SafarikaKosiceSlovak Republic
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Svorc P, Svorc P, Gresova S. Sex differences, chronobiology and general anaesthesia in activities of the autonomic nervous system in rats. Exp Physiol 2023; 108:810-817. [PMID: 36951930 PMCID: PMC10988424 DOI: 10.1113/ep091143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 03/02/2023] [Indexed: 03/24/2023]
Abstract
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.
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Affiliation(s)
- Pavol Svorc
- Department of Physiology and Pathophysiology, Faculty of MedicineOstrava UniversityOstravaCzech Republic
| | - Pavol Svorc
- Department of Physiology and Pathophysiology, Faculty of MedicineOstrava UniversityOstravaCzech Republic
- Department of Physiology, Faculty of MedicineSafarik UniversityKošiceSlovak Republic
| | - Sona Gresova
- Department of Physiology, Faculty of MedicineSafarik UniversityKošiceSlovak Republic
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Svorc P, Svorc P. General anesthesia and electrocardiographic parameters in in vivo experiments involving rats. Physiol Res 2022; 71:177-192. [PMID: 35275702 PMCID: PMC9150551 DOI: 10.33549/physiolres.934848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/18/2022] [Indexed: 11/25/2022] Open
Abstract
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.
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Affiliation(s)
- Pavol Svorc
- Department of Physiology, Medical Faculty, Safarik University, Kosice, Slovak Republic
- Department of Physiology and Patophysiology, Medical Faculty, Ostrava University, Ostrava, Czech Republic
| | - Pavol Svorc
- Department of Physiology and Patophysiology, Medical Faculty, Ostrava University, Ostrava, Czech Republic
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Kurosaka Y, Machida S, Shiroya Y, Yamauchi H, Minato K. Protective Effects of Voluntary Exercise on Hepatic Fat Accumulation Induced by Dietary Restriction in Zucker Fatty Rats. Int J Mol Sci 2021; 22:2014. [PMID: 33670590 PMCID: PMC7922922 DOI: 10.3390/ijms22042014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 12/11/2022] Open
Abstract
Weight control based on dietary restriction (DR) alone can cause lipid metabolic failure and progression to fatty liver. This study aimed to investigate the effect of exercise on preventing DR-induced hepatic fat accumulation in Zucker fatty (ZF) rats by focusing on the relationship between adipose tissue lipolysis and hepatic fat uptake. Six-week-old male ZF rats were randomly assigned to obese, DR, or DR with exercise (DR + Ex) groups. The DR and DR + Ex groups were fed a restricted diet, with the latter also undergoing voluntary exercise. After 6 weeks, hepatic fat accumulation was observed in the DR group, whereas intrahepatic fat was markedly reduced in the DR + Ex group. Compared with the obese (Ob) group, the DR group exhibited 2.09-fold expression of hepatic fatty acid translocase (FAT)/CD36 proteins (p < 0.01) and 0.14-fold expression of hepatic fatty acid-binding protein (FABP)1 (p < 0.01). There were no significant differences between the DR + Ex group and the Ob group. FAT/CD36 and hepatic triglyceride (TG) expression levels were strongly positively correlated (r = 0.81, p < 0.001), whereas there was a strong negative correlation between FABP1 and hepatic TG expression levels (r = -0.65, p < 0.001). Our results suggest that hepatic fat accumulation induced by DR in ZF rats might be prevented through exercise-induced modifications in FAT/CD36 and FABP1 expression.
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Affiliation(s)
- Yuka Kurosaka
- Faculty of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Shuichi Machida
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan;
| | - Yoko Shiroya
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Hideki Yamauchi
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Kumiko Minato
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
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Jarmolowicz DP, Hudnall JL, Hale L, Fowler SC, Bortolato M, Lemley SM, Sofis MJ. Delay discounting as impaired valuation: Delayed rewards in an animal obesity model. J Exp Anal Behav 2018; 108:171-183. [PMID: 28940395 DOI: 10.1002/jeab.275] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 07/26/2017] [Indexed: 12/21/2022]
Abstract
Obesity is a major public health problem, which, like many forms of addiction, is associated with an elevated tendency to choose smaller immediate rather than larger delayed rewards, a response pattern often referred to as excessive delay discounting. Although some accounts of delay discounting conceptualize this process as impulsivity (placing the emphasis on overvaluing the smaller immediate reward), others have conceptualized delay discounting as an executive function (placing the emphasis on delayed rewards failing to retain their value). The present experiments used a popular animal model of obesity that has been shown to discount delayed rewards at elevated rates (i.e., obese Zucker rats) to test two predictions that conceptualize delay discounting as executive function. In the first experiment, acquisition of lever pressing with delayed rewards was compared in obese versus lean Zucker rats. Contrary to predictions based on delay discounting as executive function, obese Zucker rats learned to press the lever more quickly than controls. In the second experiment, progressive ratio breakpoints (a measure of reward efficacy) with delayed rewards were compared in obese versus lean Zucker rats. Contrary to the notion that obese rats fail to value delayed rewards, the obese Zucker rats' breakpoints were (at least) as high as those of the lean Zucker rats.
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Inagaki H, Kuwahara M, Tsubone H. Effect of post-weaning individual housing on autonomic responses in male rats to sexually receptive female rats. Exp Anim 2014; 62:229-35. [PMID: 23903058 PMCID: PMC4160948 DOI: 10.1538/expanim.62.229] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Post-weaning individual housing induces significant alterations in the reward system of
adult male rats presented with sexually receptive female rats. In this study, we examined
the effects of post-weaning individual housing on autonomic nervous activity in adult male
rats during encounters with sexually receptive female rats to assess whether different
affective states depending on post-weaning housing conditions are produced. Changes in
heart rate and spectral parameters of heart rate variability indicated that in
post-weaning individually housed male rats, both sympathetic and parasympathetic activity
increased with no change in the sympathovagal balance, while in post-weaning socially
housed male rats, both sympathetic and parasympathetic activity decreased with a
predominance of parasympathetic activity. These two patterns of shifts in sympathovagal
balances closely resembled changes in autonomic nervous activity with regard to classical
appetitive conditioning in male rats. The autonomic changes in male rats housed
individually after weaning corresponded to changes associated with the reward-expecting
state evoked by the conditioned stimulus, and the autonomic changes observed in male rats
housed socially after weaning corresponded to changes associated with the reward-receiving
state evoked by the unconditioned stimulus. These results suggest that different affective
states were induced in adult male rats during sexual encounters depending on male–male
social interactions after weaning. The remarkable change caused by post-weaning individual
housing may be ascribed to alteration of the reward system during sexual encounters
induced by deficiency of intermale social communication after weaning.
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Affiliation(s)
- Hideaki Inagaki
- Department of Comparative Pathophysiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Lee KH, Yoon K, Ha M, Park J, Cho SH, Kang D. Heart rate variability and urinary catecholamines from job stress in korean male manufacturing workers according to work seniority. INDUSTRIAL HEALTH 2010; 48:331-338. [PMID: 20562509 DOI: 10.2486/indhealth.48.331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The aim of this study was to evaluate the relationships between job stress and indicators of autonomic nervous system activity in employees of the manufacturing industry. A total of 140 employees from a company that manufactures consumer goods (i.e., diapers and paper towels) were recruited for participation in this study. Job stress was assessed using Karasek's Job Content Questionnaire. Heart rate variability (HRV) was measured using a heart rate monitor, and urinary catecholamines were measured by an HPLC-ECD. Information on demographic characteristics, previous job history, smoking status and alcohol consumption was also collected. Job stress did not have a significant effect on HRV or catecholamines. However, low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. Low- and high-frequency HRV were higher in the high-strain group than in the low-strain group, but these differences were not statistically significant. The results of the present study indicate that low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. In addition, the results of this study show that HRV can be used as a potential physiologic indicator of job stress in employees with a short duration of employment.
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Affiliation(s)
- Kyoung-Ho Lee
- Integrated Omics Center, Life/Health Division, Korea Institute of Science and Technology, Seoul 136-791, Korea
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Cosson E, Valensi P, Laude D, Mesangeau D, Dabire H. Arterial stiffness and the autonomic nervous system during the development of Zucker diabetic fatty rats. DIABETES & METABOLISM 2009; 35:364-70. [PMID: 19648048 DOI: 10.1016/j.diabet.2009.02.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 11/25/2022]
Abstract
AIM This study aimed to investigate the role played by sympathovagal balance in arterial stiffness, a common feature of insulin resistance and type 2 diabetes. METHODS We investigated the relationship between autonomic nervous system activity and arterial stiffness in Zucker diabetic fatty rats (ZDF: Gmi-fa/fa) and their age-matched controls (lean: ?/fa). Using simultaneous catheterization of the proximal and distal aorta, we measured intra-arterial blood pressure (BP), heart rate (HR), their variability (spectral analysis) and aortic pulse wave velocity (PWV) in a series of at least six conscious rats aged 6, 12, 18 and 24 weeks. RESULTS BP and PWV increased with age (P<0.001) in both strains with no differences between strains, despite the insulin resistance already present at 6 weeks in ZDF rats. HR was significantly lower (P<0.001) in ZDF than in lean rats. In ZDF compared with lean rats, the low-frequency (LF) component of the systolic BP variations and the LF/high-frequency (HF) component of the pulse interval (PI) variation ratio were reduced (P<0.01 and P<0.05, respectively), while the HF component of the PI (HF-PI) variation was raised (P<0.05). PWV was negatively correlated with HF-PI (r=-0.37, P<0.01), but not with biochemical parameters. HF-PI was an independent variable explaining the variation in PWV. CONCLUSION During the development of disease of ZDF rats, sympathovagal balance might account for the lack of increase in PWV.
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Affiliation(s)
- E Cosson
- Inserm, EMI-U0107, Paris, France.
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Diabetes and cardiovascular autonomic dysfunction: application of animal models. Auton Neurosci 2008; 145:3-10. [PMID: 19054720 DOI: 10.1016/j.autneu.2008.10.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 10/17/2008] [Accepted: 10/21/2008] [Indexed: 12/21/2022]
Abstract
When diabetes is associated with cardiovascular autonomic dysfunction, there is a poor prognosis and increased morbidity and mortality. Information on the mechanisms of diabetes-associated autonomic dysfunction has been provided by advanced studies using physiological, pharmacological, anatomical and molecular methods in experimental animal models of insulin deficiency and resistance. This has been augmented by new approaches which combine diabetes induction with genetically modified animal models. The aim of this review is to outline and discuss the animal models used for the study of insulin deficiency and insulin resistance with a focus on autonomic neural interactions. The goal is to better understand the clinical relevance of cardiovascular autonomic dysfunction associated with diabetes.
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Di Nardo F, Burattini R, Cogo CE, Faelli E, Ruggeri P. Age-related analysis of insulin resistance, body weight and arterial pressure in the Zucker fatty rat. Exp Physiol 2008; 94:162-8. [PMID: 18820002 DOI: 10.1113/expphysiol.2008.044529] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The evolution with ageing of insulin resistance, body weight (BW) and mean arterial pressure (MAP) was studied in a group of Zucker fatty rats (ZFRs, n = 22), between 7 and 16 weeks of age, compared with an age-matched control group of Zucker lean rats (ZLRs, n = 22). The minimal model of glucose kinetics was applied to estimate glucose effectiveness, S(G), and insulin sensitivity, S(I), from insulinaemia and glycaemia measured during a 70 min intravenous glucose tolerance test. No correlation was found between S(G) and age in both ZFR and ZLR groups. No significant changes in mean S(G) between the two groups indicated no alteration of glucose-mediated glucose disposal. Estimates of S(I) from individual ZFRs were independent of age and, on average, showed 83% reduction (P < 0.001) compared with the ZLR group. Despite the lack of alteration of S(I) with age, the ZFR group showed an age-related increase of MAP, which correlated with increasing BW (r = 0.71 and P < 0.001). These results support the hypothesis that in our ZFRs, as a suitable genetic model of obesity and hypertension, insulin resistance is fully established at the age of 7 weeks and remains practically unaltered until at least the sixteenth week. An age-related increase in arterial pressure, observed in this strain, relates more properly to increasing BW, rather than insulin resistance. Development of hypertension with increasing age and BW may result from an enhanced insulin-mediated activity of the sympathetic nervous system, as observed in our previously reported study.
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Affiliation(s)
- Francesco Di Nardo
- Department of Biomedical, Electronics and Telecommunication Engineering, Polytechnic University of Marche, 60131 Ancona, Italy
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Rowan WH, Campen MJ, Wichers LB, Watkinson WP. Heart rate variability in rodents: uses and caveats in toxicological studies. Cardiovasc Toxicol 2007; 7:28-51. [PMID: 17646680 DOI: 10.1007/s12012-007-0004-6] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 01/04/2023]
Abstract
Heart rate variability (HRV) is a measure of cardiac pacing dynamics that has recently garnered a great deal of interest in environmental health studies. While the use of these measures has become popular, much uncertainty remains in the interpretation of results, both in terms of human and animal research. In humans, HRV endpoints, specifically chronic alterations in baseline HRV patterns, have been reasonably well characterized as prognostic indicators of adverse outcomes for a variety of diseases. However, such information is lacking for reversible HRV changes that may be induced by short-term exposures to environmental toxicants. Furthermore, there are minimal substantive data, either acute or chronic, regarding the pathological interpretation or prognostic value of toxicant-induced changes in HRV in rodents. The present report summarizes the physiological and clinical aspects of HRV, the methodological processes for obtaining these endpoints, and previous human and animal studies in the field of environmental health. Furthermore, we include a discussion of important caveats and recommendations for the interpretation of HRV data in animal research.
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Affiliation(s)
- William H Rowan
- Pulmonary Toxicology Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA
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De Angelis K, D'Agord Schaan B, Rodrigues B, Malfitano C, Irigoyen MC. Disfunção autonômica cardiovascular no diabetes mellitus experimental. ACTA ACUST UNITED AC 2007; 51:185-94. [PMID: 17505625 DOI: 10.1590/s0004-27302007000200007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Accepted: 01/03/2007] [Indexed: 01/17/2023]
Abstract
Muitas informações novas têm sido publicadas nos últimos anos a respeito da fisiopatologia da disfunção autonômica cardiovascular em ratos e camundongos diabéticos. Nosso grupo tem estudado o curso temporal das alterações cardiovasculares associadas ao diabetes experimental há alguns anos, obtendo evidências consistentes de grave disautonomia em modelos animais de diabetes. O objetivo deste trabalho foi revisar a contribuição que estudos envolvendo diferentes modelos de deficiência e resistência à insulina têm fornecido para o entendimento, tratamento e prevenção da disfunção autonômica cardiovascular do diabetes.
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Dabisch PA, Miller DB, Reutter SA, Mioduszewski RJ, Thomson SA. Miotic Tolerance to Sarin Vapor Exposure: Role of the Sympathetic and Parasympathetic Nervous Systems. Toxicol Sci 2005; 85:1041-7. [PMID: 15788726 DOI: 10.1093/toxsci/kfi151] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
O-isopropyl methylphosphonofluoridate, also known as sarin or GB, is a highly toxic organophosphorous compound that exerts its effect by inhibiting the enzyme acetylcholinesterase. While the effects of a single exposure to GB vapor are well characterized, the effects of multiple exposures to GB vapor are less clear. Previous studies in the rat and guinea pig have demonstrated that multiple exposures result in tolerance to the miotic effect of nerve agents. The aim of the present study was to examine potential mechanisms responsible for tolerance to the miotic effect of GB vapor that has been observed in the rat after multiple exposures. Multiple whole-body inhalation exposures to GB vapor were conducted in a dynamic airflow chamber. Exposures lasted 60 min and each of the three exposures occurred at 24-h intervals. The results of the present study demonstrate that the alpha-adrenergic antagonist phentolamine and the beta-adrenergic receptor antagonist propranolol did not affect the development of tolerance to the miotic effect of GB vapor, suggesting that enhanced sympathetic tone to the eye is not responsible for the observed tolerance. Administration of atropine before the first exposure prevented the tolerance to the miotic effect of GB vapor after the third exposure, suggesting that the tolerance is the result of muscarinic receptor desensitization secondary to receptor stimulation. The present study extends the findings of previous studies to strengthen the hypothesis that the miotic tolerance observed in the rat upon repeated exposure to nerve agents is due to desensitization of muscarinic acetylcholine receptors located on the pupillary sphincter.
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Affiliation(s)
- Paul A Dabisch
- National Academy of Sciences-National Research Council, Washington, DC, USA.
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