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Related to autonomic drug: autonomic agent
any of a large group of drugs that mimic or modify the function of the autonomic nervous system.
not subject to voluntary control.
autonomic craniosacral outflow
the parasympathetic nervous system includes nerve fibers in the oculomotor, facial and glossopharyngeal and vagal cranial nerves. The sacral outflow includes autonomic fibers in the ventral nerve roots of the sacral nerves.
autonomic ganglionic blocking agent
nicotine and some synthetic compounds such as hexamethonium, pentamethonium and others specifically paralyze the nerve cells in autonomic ganglia thus neutralizing the sympathetic and parasympathic postganglionic fibers that emanate from that particular ganglion.
autonomic nervous system
see autonomic nervous system.
autonomic parasympathetic effects
include constriction of the pupil and the bronchioles, increased secretory activity of glands, increased tone and motility of the gut, relaxation of the sphincters.
autonomic reflex arc
comprises the afferent fibers from sensory end organs which pass into the spinal cord via the dorsal roots, ascend through the sensory columns in the spinal cord to the hypothalamus. Efferent fibers pass from there to subhypothalamic motor levels.
autonomic sympathetic effects
include the fight-or-flight reactions of dilatation of blood vessels to muscles, constriction of others, dilatation of pupils and bronchioles, and inhibition of glandular and plain muscle activity.
autonomic thoracolumbar outflow
the sympathetic nervous system consists of neurons in the intermediolateral gray column of the thoracic and lumbar segments of the spinal cord which leave the cord in the ventral branches of thoracic and lumbar nerves. Once outside the vertebral column the neurons leave the spinal nerve and join the paravertebral sympathetic trunk to enter ganglia from which postganglionic fibers go their separate ways to effector organs.