sympathetic nervous system

sympathetic nervous system

n.

The part of the autonomic nervous system originating in the thoracic and lumbar regions of the spinal cord that in general inhibits or opposes the physiological effects of the parasympathetic nervous system, as in tending to reduce digestive secretions, speeding up the heart, and contracting blood vessels.

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sympathetic nervous system  (smp-thtk)

The part of the autonomic nervous system that tends to act in opposition to the parasympathetic nervous system, as by speeding up the heartbeat and causing contraction of the blood vessels. It regulates the function of the sweat glands and stimulates the secretion of glucose in the liver. The sympathetic nervous system is activated especially under conditions of stress. Compare parasympathetic nervous system.

Thesaurus

Noun

1.

sympathetic nervous system - originates in the thoracic regions of the spinal cord; opposes physiological effects of the parasympathetic: reduces digestive secretions; speeds the heart; contracts blood vessels nervous system, systema nervosum - the sensory and control apparatus consisting of a network of nerve cells ANS, autonomic nervous system - the part of the nervous system of vertebrates that controls involuntary actions of the smooth muscles and heart and glands splanchnic nerve - any of several nerves of the sympathetic part of the autonomic nervous system that innervate viscera and blood vessels abdominal nerve plexus, coeliac plexus, plexus celiacus, solar plexus - a large plexus of sympathetic nerves in the abdomen behind the stomach alpha receptor, alpha-adrenergic receptor, alpha-adrenoceptor - receptors postulated to exist on nerve cell membranes of the sympathetic nervous system in order to explain the specificity of certain agents that affect only some sympathetic activities (such as vasoconstriction and relaxation of intestinal muscles and contraction of smooth muscles) beta receptor, beta-adrenergic receptor, beta-adrenoceptor - receptors postulated to exist on nerve cell membranes of the sympathetic nervous system in order to explain the specificity of certain agents that affect only some sympathetic activities (such as vasodilation and increased heart beat)