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Updated: Jul 21, 2026
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Quantitative Autonomic Testing
Published on: July 19, 2011
Basal sympatho-adrenal function in quadriplegic man
Journal of the Autonomic Nervous System
|December 1, 1980
Summary
Plasma catecholamines (CA) in quadriplegic men showed wide fluctuations, with higher epinephrine levels than normal. These levels indicate normal or increased sympatho-adrenal tone, likely controlled by spinal reflexes.
Area of Science:
- Neuroscience
- Physiology
- Endocrinology
Background:
- Quadriplegia can affect autonomic nervous system function.
- Understanding sympatho-adrenal activity is crucial for managing autonomic dysfunction.
Purpose of the Study:
- To investigate plasma catecholamine levels in chronic quadriplegic individuals.
- To assess resting sympatho-adrenal tone in quadriplegia.
Main Methods:
- Measured plasma catecholamines (norepinephrine and epinephrine) at 15-minute intervals over 4 hours in 5 quadriplegic males.
- Correlated catecholamine spikes with physiological events like muscle spasms, urination, pain, blood pressure, and heart rate changes.
Main Results:
- Plasma catecholamine levels fluctuated significantly, with frequent bursts of high levels.
- Median plasma norepinephrine levels were within the normal range, but epinephrine levels were elevated compared to controls.
- Positive correlation between norepinephrine and epinephrine levels was observed in most subjects.
Conclusions:
- Resting sympatho-adrenal tone in quadriplegics is not decreased; it is normal or increased.
- Activation of the sympatho-adrenal system in quadriplegia may be mediated by local spinal reflexes.
- Spinal reflexes appear capable of maintaining resting autonomic functions in quadriplegics.
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