Vagal determinants of exercise capacity
Asif Machhada1,2, Stefan Trapp1, Nephtali Marina1
1Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
Nature Communications
|May 19, 2017
Summary
This study demonstrates that brainstem vagal neurons directly control exercise capacity in rats. Manipulating these neurons impacts cardiac function and endurance, revealing a neural basis for exercise performance decline.
Area of Science:
- Neuroscience
- Cardiovascular Physiology
- Exercise Science
Background:
- Cardiac vagal activity is linked to exercise capacity, but a causal link is unproven.
- The specific neural circuits governing this relationship remain unclear.
Purpose of the Study:
- To establish a causal relationship between brainstem vagal neurons and exercise capacity.
- To investigate the role of the dorsal vagal motor nucleus in regulating parasympathetic drive and physical performance.
Main Methods:
- Genetic silencing of dorsal vagal motor nucleus neurons in rats.
- Optogenetic stimulation of these specific vagal preganglionic neurons.
- Assessment of exercise capacity, cardiac contractility, and endurance.
Main Results:
- Genetic silencing of these neurons significantly reduced exercise capacity.
- Optogenetic activation enhanced cardiac contractility and prolonged exercise endurance.
- These findings pinpoint a critical CNS circuit for exercise performance.
Conclusions:
- Parasympathetic vagal drive from a defined brainstem circuit is essential for exercise ability.
- Dysfunction of these neurons may underlie age-related and disease-associated declines in exercise capacity.
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