II. Definitions
- Sympathetic Nervous System
- Part of Autonomic Nervous System with activity that typically counters the Parasympathetic Nervous System
- Energy expending (catabolic) system, activated in stressful situations (e.g. emergency fight or flight)
- Contrast with the Parasympathetic Nervous System, an energy conserving system activated at times of rest
III. Physiology: Activity
- See Adrenergic Receptor
- See Alpha Adrenergic Receptor (alpha 1 and alpha 2)
- See Beta Adrenergic Receptor (beta 1 and beta 2)
- Increases Heart Rate (chronotropic), heart contraction strength (ionotropic), Blood Pressure
- Increases Respiratory Rate and bronchodilation
- Increases pupil size or Mydriasis (contrast with Miosis and accommodation by the Parasympathetic System)
- Stimulates Salivary VISCOUS secretion (contrast with watery secretion by Parasympathetic System)
- Stimulates sweat secretion (via Cholinergic postganglionic fibers)
- Decreases gastrointestinal activity and secretion, and contracts gastrointestinal sphincters
- Stimulates liver Gluconeogenesis and glycogenesis and fat lipolysis
- Stimulates Kidney renin release and Adrenal MedullaEpinephrine release (Cholinergic postganglionic fibers)
- Mediates ejaculation (contrast with Erection mediated by Parasympathetic System)
- Shunts Blood Flow to critical organs
IV. Anatomy
- Thoracolumbar division of the Autonomic Nervous System
- Signals originate in the spinal cord intermediolateral column (T1 to L2)
- Sympathetic Ganglionic chain extends from the foramen magnum to the low Sacrum
- Preganglionic nerves enter the paravertebral sympathetic Ganglionic chain
- Preganglionic nerves may traverse the chain several levels up or down before synapsing
- Preganglionic nerves Synapse at paravertebral or prevertebral ganglia
- Trigger postganglionic nerves via NeurotransmitterAcetylcholine
- Postganglionic Neuron (autonomic Ganglion to target organ)
- Norepinephrine mediated (with exceptions, such as Acetylcholine for sweating)
- Contrast with parasympathetic postganglionic fibers which release Acetylcholine
- Images
V. Pathophysiology
VI. References
- Goldberg (2014) Clinical Neuroanatomy, Medmaster, p. 54-60
- Netter (1997) Atlas Human Anatomy, ICON Learning, p. 152-4
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| Definition (NCI_NCI-GLOSS) | The part of the nervous system that increases heart rate, blood pressure, breathing rate, and pupil size. It also causes blood vessels to narrow and decreases digestive juices. |
| Definition (MSH) | The thoracolumbar division of the autonomic nervous system. Sympathetic preganglionic fibers originate in neurons of the intermediolateral column of the spinal cord and project to the paravertebral and prevertebral ganglia, which in turn project to target organs. The sympathetic nervous system mediates the body's response to stressful situations, i.e., the fight or flight reactions. It often acts reciprocally to the parasympathetic system. |
| Definition (CSP) | portion of the autonomic nervous system that receives its fibers of connection with the central nervous system through the thoracolumbar outflow of visceral efferent fibers; sympathetic preganglionic fibers originate in neurons of the intermediolateral column of the spinal cord and project to the paravertebral and prevertebral ganglia, which in turn project to target organs; the sympathetic nervous system mediates the body's response to stressful situations, i.e, the fight or flight reactions, and often acts reciprocally to the parasympathetic system. |
| Concepts | Body System (T022) |
| MSH | D013564 |
| SnomedCT | 68365008 |
| English | Nervous Systems, Sympathetic, Sympathetic Nervous Systems, System, Sympathetic Nervous, Systems, Sympathetic Nervous, Nervous System, Sympathetic, SNS - Sympathetic nervous syst, SNS - Sympathetic nervous system, Pars sympathica divisionis autonomici systematis nervosi, Sympathetic part of autonomic division of nervous system, Structure of sympathetic nervous system, nervous sympathetic system, nervous system sympathetic, sympathetic nervous system, Sympathetic nervous system, Sympathetic nervous system structure (body structure), Sympathetic nervous system structure, Sympathetic nervous system, NOS, Sympathetic Nervous System, SNS |
| Swedish | Sympatiska nervsystemet |
| Czech | sympatický nervový systém |
| Finnish | Sympaattinen hermosto |
| Russian | NERVNAIA SISTEMA SIMPATICHESKAIA, НЕРВНАЯ СИСТЕМА СИМПАТИЧЕСКАЯ |
| Croatian | SIMPATIČKI ŽIVČANI SUSTAV |
| Latvian | Simpātiskā nervu sistēma, Nervu sistēma, simpātiskā |
| Polish | Układ nerwowy adrenergiczny, Układ nerwowy współczulny |
| Norwegian | Sympatiske nervesystem |
| Spanish | estructura del sistema nervioso simpático (estructura corporal), estructura del sistema nervioso simpático, sistema nervioso simpático, Sistema Nervioso Simpático |
| French | Système nerveux orthosympathique, Système nerveux sympathique |
| German | Nervensystem, sympathisches, Sympathisches Nervensystem |
| Italian | Sistema nervoso simpatico |
| Dutch | Sympathisch zenuwstelsel, Zenuwstelsel, sympathisch |
| Portuguese | Sistema Nervoso Simpático |
Ontology: Sympathetic nerve structure (C0459521)
| Concepts | Body Part, Organ, or Organ Component (T023) |
| SnomedCT | 90456006 |
| English | nerve sympathetic, sympathetic nerve, nerves sympathetic, Sympathetic nerve, Sympathetic nerve structure (body structure), Sympathetic nerve structure, Sympathetic nerve, NOS |
| Spanish | estructura del nervio simpático (estructura corporal), estructura del nervio simpático, nervio simpático |
