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Ventilatory Response to Mechanoreceptor Activation Not Altered in Human Hypertension
Jacob T Caldwell1, Eric J Bruhn1, Joshua R Smith1
1Department of Cardiovascular Medicine, Mayo Clinic, Rochester MN.
Respiratory Physiology & Neurobiology
|August 10, 2026
Summary
Mechanically sensitive afferent stimulation does not alter breathing in hypertension. This study found no augmented ventilatory responses in adults with hypertension (HTN) during passive leg movement, suggesting HTN does not impact this reflex.
Area of Science:
- Physiology
- Cardiovascular Research
- Respiratory Physiology
Background:
- Hypertension (HTN) is a prevalent cardiovascular condition.
- Altered autonomic nervous system function is common in HTN.
- The role of mechanically sensitive afferents in ventilatory control during HTN is not fully understood.
Purpose of the Study:
- To investigate whether mechanically sensitive afferent stimulation augments ventilatory responses in individuals with hypertension.
- To compare ventilatory responses to passive leg movement between hypertensive and control groups.
Main Methods:
- Participants included adults with HTN and age-matched controls.
- Mechanically sensitive afferents were stimulated using 30-second passive leg movements.
- Ventilatory variables (ventilation, breathing frequency, tidal volume) were measured breath-by-breath at rest and during stimulation.
Main Results:
- Ventilation and breathing frequency increased over time during stimulation in both groups (p<0.01).
- No significant differences were found between the hypertensive and control groups for any ventilatory variable.
- Tidal volume did not significantly change over time or differ between groups.
Conclusions:
- Mechanically sensitive afferent stimulation does not elicit an augmented ventilatory response in adults with hypertension.
- The findings suggest that the ventilatory control system related to mechanically sensitive afferents is not significantly altered in hypertension.
- Further research may explore other afferent pathways or different stimuli in hypertensive populations.
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