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Age-related reflex responses from peripheral and central chemoreceptors in healthy men.

Paleczny B, Niewiński P, Rydlewska A, Piepoli MF, Borodulin-Nadzieja L, Jankowska EA, Ponikowska B - Clin. Auton. Res. (2014)

Bottom Line: We found a significantly different pattern of hemodynamic responses from peripheral chemoreceptors between the older and the younger groups.Blunted HR response was related to reduced BRS and sympathovagal imbalance characterized by reduced vagal tone.Impaired arterial baroreflex and sympathovagal imbalance related to ageing may contribute to decreased heart rate response, but not to increased blood pressure response from peripheral chemoreceptors.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Wroclaw Medical University, ul. Chałubińskiego 10, 50-368, Wroclaw, Poland, bpaleczny@onet.eu.

ABSTRACT

Objective: The study aimed: (i) to characterize reflex responses from peripheral and central chemoreceptors in different age groups of healthy men (<50 years old vs ≥50 years old) and, (ii) to assess, within these groups, whether there is any relationship between ventilatory and hemodynamic responses from chemoreceptors and indices of autonomic nervous system (ANS).

Methods: Peripheral chemoreflex sensitivity was assessed by the transient hypoxia method and respiratory, heart rate (HR) and blood pressure responses were calculated. Central chemoreflex sensitivity was assessed by the rebreathing method and respiratory response was calculated. ANS was assessed using heart rate variability indices and baroreflex sensitivity (BRS).

Results: Sixty-seven healthy men were divided into 2 groups: <50 years (n = 38, mean age: 32 ± 10 years) and ≥50 years (n = 29, mean age: 61 ± 8 years). There were no differences in respiratory response from central and peripheral chemoreceptors between the older and younger groups of healthy males. We found a significantly different pattern of hemodynamic responses from peripheral chemoreceptors between the older and the younger groups. The former expressed attenuated HR acceleration and exaggerated blood pressure increase in response to transient hypoxia. Blunted HR response was related to reduced BRS and sympathovagal imbalance characterized by reduced vagal tone. Blood pressure responses seemed to be independent of sympathovagal balance and BRS.

Interpretation: Ageing impacts hemodynamic rather than respiratory response from chemoreceptors. Impaired arterial baroreflex and sympathovagal imbalance related to ageing may contribute to decreased heart rate response, but not to increased blood pressure response from peripheral chemoreceptors.

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Related in: MedlinePlus

Graph relating age to the following chemoreflex sensitivity measures: a central chemoreflex sensitivity in terms of respiratory response (CChS-Ve), b peripheral chemoreflex sensitivity in terms of respiratory response (PChS-Ve), c peripheral chemoreflex sensitivity in terms of heart rate response (PChS-HR), d peripheral chemoreflex sensitivity in terms of systolic blood pressure response (PChS-SBP); (ln), natural logarithm
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Fig3: Graph relating age to the following chemoreflex sensitivity measures: a central chemoreflex sensitivity in terms of respiratory response (CChS-Ve), b peripheral chemoreflex sensitivity in terms of respiratory response (PChS-Ve), c peripheral chemoreflex sensitivity in terms of heart rate response (PChS-HR), d peripheral chemoreflex sensitivity in terms of systolic blood pressure response (PChS-SBP); (ln), natural logarithm

Mentions: There were no differences in respiratory response from central (CChS-Ve) and peripheral chemoreceptors (PChS-Ve) between two groups. However, significant differences were found in hemodynamic responses from peripheral chemoreceptors. The older group reacted to transient hypoxia with a lower heart rate acceleration, but greater systolic blood pressure increase than the younger group (Table 1; Fig. 3).Fig. 3


Age-related reflex responses from peripheral and central chemoreceptors in healthy men.

Paleczny B, Niewiński P, Rydlewska A, Piepoli MF, Borodulin-Nadzieja L, Jankowska EA, Ponikowska B - Clin. Auton. Res. (2014)

Graph relating age to the following chemoreflex sensitivity measures: a central chemoreflex sensitivity in terms of respiratory response (CChS-Ve), b peripheral chemoreflex sensitivity in terms of respiratory response (PChS-Ve), c peripheral chemoreflex sensitivity in terms of heart rate response (PChS-HR), d peripheral chemoreflex sensitivity in terms of systolic blood pressure response (PChS-SBP); (ln), natural logarithm
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4256521&req=5

Fig3: Graph relating age to the following chemoreflex sensitivity measures: a central chemoreflex sensitivity in terms of respiratory response (CChS-Ve), b peripheral chemoreflex sensitivity in terms of respiratory response (PChS-Ve), c peripheral chemoreflex sensitivity in terms of heart rate response (PChS-HR), d peripheral chemoreflex sensitivity in terms of systolic blood pressure response (PChS-SBP); (ln), natural logarithm
Mentions: There were no differences in respiratory response from central (CChS-Ve) and peripheral chemoreceptors (PChS-Ve) between two groups. However, significant differences were found in hemodynamic responses from peripheral chemoreceptors. The older group reacted to transient hypoxia with a lower heart rate acceleration, but greater systolic blood pressure increase than the younger group (Table 1; Fig. 3).Fig. 3

Bottom Line: We found a significantly different pattern of hemodynamic responses from peripheral chemoreceptors between the older and the younger groups.Blunted HR response was related to reduced BRS and sympathovagal imbalance characterized by reduced vagal tone.Impaired arterial baroreflex and sympathovagal imbalance related to ageing may contribute to decreased heart rate response, but not to increased blood pressure response from peripheral chemoreceptors.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Wroclaw Medical University, ul. Chałubińskiego 10, 50-368, Wroclaw, Poland, bpaleczny@onet.eu.

ABSTRACT

Objective: The study aimed: (i) to characterize reflex responses from peripheral and central chemoreceptors in different age groups of healthy men (<50 years old vs ≥50 years old) and, (ii) to assess, within these groups, whether there is any relationship between ventilatory and hemodynamic responses from chemoreceptors and indices of autonomic nervous system (ANS).

Methods: Peripheral chemoreflex sensitivity was assessed by the transient hypoxia method and respiratory, heart rate (HR) and blood pressure responses were calculated. Central chemoreflex sensitivity was assessed by the rebreathing method and respiratory response was calculated. ANS was assessed using heart rate variability indices and baroreflex sensitivity (BRS).

Results: Sixty-seven healthy men were divided into 2 groups: <50 years (n = 38, mean age: 32 ± 10 years) and ≥50 years (n = 29, mean age: 61 ± 8 years). There were no differences in respiratory response from central and peripheral chemoreceptors between the older and younger groups of healthy males. We found a significantly different pattern of hemodynamic responses from peripheral chemoreceptors between the older and the younger groups. The former expressed attenuated HR acceleration and exaggerated blood pressure increase in response to transient hypoxia. Blunted HR response was related to reduced BRS and sympathovagal imbalance characterized by reduced vagal tone. Blood pressure responses seemed to be independent of sympathovagal balance and BRS.

Interpretation: Ageing impacts hemodynamic rather than respiratory response from chemoreceptors. Impaired arterial baroreflex and sympathovagal imbalance related to ageing may contribute to decreased heart rate response, but not to increased blood pressure response from peripheral chemoreceptors.

Show MeSH
Related in: MedlinePlus