autonomic nerve

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a macroscopic cordlike structure of the body, comprising a collection of nerve fibers that convey impulses between a part of the central nervous system and some other body region. See Appendix 2-6 and see color plates.

Depending on their function, nerves are known as sensory, motor, or mixed. Sensory nerves, sometimes called afferent nerves, carry information from the outside world, such as sensations of heat, cold, and pain, to the brain and spinal cord. Motor nerves, or efferent nerves, transmit impulses from the brain and spinal cord to the muscles. Mixed nerves are composed of both motor and sensory fibers, and transmit messages in both directions at once.

Together, the nerves make up the peripheral nervous system, as distinguished from the central nervous system (brain and spinal cord). There are 12 pairs of cranial nerves, which carry messages to and from the brain. Spinal nerves arise from the spinal cord and pass out between the vertebrae; there are 31 pairs, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. The various nerve fibers and cells that make up the autonomic nervous system innervate the glands, heart, blood vessels, and involuntary muscles of the internal organs.
Details of structure of components of nerve tissue.
accelerator n's the cardiac sympathetic nerves, which, when stimulated, accelerate the action of the heart.
acoustic nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
afferent nerve any nerve that transmits impulses from the periphery toward the central nervous system, such as a sensory nerve. See also neuron.
articular nerve any mixed peripheral nerve that supplies a joint and its associated structures.
auditory nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
autonomic nerve any nerve of the autonomic nervous system; called also visceral nerve.
cranial n's see cranial nerves.
cutaneous nerve any mixed peripheral nerve that supplies a region of the skin. See anatomic Table of Nerves in the Appendices.
depressor nerve
1. a nerve that lessens the activity of an organ.
2. an afferent nerve whose stimulation causes a fall in blood pressure.
efferent nerve any nerve that carries impulses from the central nervous system toward the periphery, such as a motor nerve. See also neuron.
excitor nerve one that transmits impulses resulting in an increase in functional activity.
excitoreflex nerve a visceral nerve that produces reflex action.
fusimotor n's those that innervate the intrafusal fibers of the muscle spindle.
gangliated nerve any nerve of the sympathetic nervous system.
inhibitory nerve one that transmits impulses resulting in a decrease in functional activity.
medullated nerve myelinated nerve.
mixed nerve (nerve of mixed fibers) a nerve composed of both sensory (afferent) and motor (efferent) fibers.
motor nerve a peripheral efferent nerve that stimulates muscle contraction.
myelinated nerve one whose axons are encased in a myelin sheath; called also medullated nerve.
peripheral nerve any nerve outside the central nervous system.
pilomotor n's those that supply the arrector muscles of hair.
pressor nerve an afferent nerve whose irritation stimulates a vasomotor center and increases intravascular tension.
sciatic nerve see sciatic nerve.
secretory nerve an efferent nerve whose stimulation increases vascular activity.
sensory nerve a peripheral nerve that conducts impulses from a sense organ to the spinal cord or brain. See also neuron.
somatic n's the sensory and motor nerves supplying skeletal muscle and somatic tissues.
spinal n's the 31 pairs of nerves arising from the spinal cord and passing out through the vertebrae; there are eight cervical, twelve thoracic, five lumbar, five sacral, and one coccygeal. , and see anatomic Table of Nerves in the Appendices.
Spinal nerves emerging from the spinal cord through the intervertebral foramina with muscles or muscle movements listed for specific levels. From McQuillan et al., 2002.
splanchnic n's those of the blood vessels and viscera, especially the visceral branches of the thoracic, abdominal (lumbar), and pelvic parts of the sympathetic trunks. See Appendix 3-5.
sudomotor n's those that innervate the sweat glands.
sympathetic n's
2. any nerve of the sympathetic nervous system.
trophic nerve one concerned with regulation of nutrition.
unmyelinated nerve one whose axons are not encased in a myelin sheath.
vasoconstrictor nerve one whose stimulation causes contraction of blood vessels.
vasodilator nerve one whose stimulation causes dilation of blood vessels.
vasomotor nerve one concerned in controlling the caliber of vessels, whether as a vasoconstrictor or vasodilator.
vasosensory nerve any nerve supplying sensory fibers to the vessels.
visceral nerve autonomic nerve.

au·to·nom·ic nerve

a bundle of autonomic nerve fibers outside the central nervous system belonging or relating to the autonomic (visceral motor) nervous system.
Synonym(s): nervus autonomicus [TA]

autonomic nerve

Etymology: Gk, autos, self, nomos, law, neuron, nerve
a nerve of the autonomic nervous system, which includes both the sympathetic and parasympathetic nervous systems. It possesses the ability to function independently and spontaneously as needed to maintain optimal status of body activities.

autonomic nerve

A visceral motor (visceral efferent) nerve, innervating smooth muscle, cardiac muscle, or glands. Visceral motor nerves can contain pre- or postganglionic sympathetic or parasympathetic axons. Visceral sensory (visceral afferent) axons can run in autonomic or somatic nerves.
See also: nerve
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One of the challenging issues during the rectal mobilization in rectopexy is the damage to the autonomic nerve during rectopexy in the young sexually active patients resulting in sexual impairment and dyspaerunia.
In literature, radical surgical resection appears to be the most promising and solely curative treatment regimen for gastrointestinal autonomic nerve tumours.
Autonomic nerves regulate the tone of vascular smooth muscle.
Thus, these findings are the first to indicate that the effects of SSYX on AF vulnerability by modulating autonomic nerve activity.
Our results have demonstrated that trimetazidine could maintain the balance of autonomic nerves and regulate the heart by improving the metabolism of ischemia myocardial cells in elderly patients with ACS.
Cardiovascular protection by oestrogen is partly mediated through modulation of autonomic nerve function.
Kondo M, Hirano T, Okamura Y, Changes in autonomic nerve function during the normal menstrual cycle measured by the coefficient of variation of R-R intervals Japan School of Medicine, Fukuoka 1989, 41 (5): 513-518.
In this study we also investigated autonomic nerve impairment and SSR was absent in 79.
6] They may not be sensitive enough to reveal subtle effects of interventions on autonomic nerve function.
A number of presentations from FIOCRUZ, Brazil, presented various modalities for testing, including the vasomotor reflex (VMR) as a test of autonomic nerve function.

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