Glossary
- Alpha ( α) Adrenergic Receptor
- one of the receptors to which epinephrine and norepinephrine bind, which comes in three subtypes
- α1, α2, and α3
- Acetylcholine
- (ACh) neurotransmitter that binds at a motor end-plate to trigger depolarization
- Adrenal Medulla
- interior portion of the adrenal (or suprarenal) gland that releases epinephrine and norepinephrine into the bloodstream as hormones
- Adrenergic
- synapse where norepinephrine is released, which binds to α1- or β-adrenergic receptors
- Agonist
- any exogenous substance that binds to a receptor and produces a similar effect to the endogenous ligand
- Antagonist
- any exogenous substance that binds to a receptor and produces an opposing effect to the endogenous ligand
- Anticholinergic Drug
- (can be a muscarinic antagonist) drugs that interrupt or reduce the function of the parasympathetic system
- Autonomic Reflex
- (visceral reflex)reflex involving an internal organ as the effector, under the control of the autonomic nervous system
- Autonomic Tone
- tendency of an organ system to be governed by one division of the autonomic nervous system over the other, such as heart rate being lowered by parasympathetic input at rest
- Beta (?)Adrenergic Receptor
- one of the receptors to which epinephrine and norepinephrine bind, which comes in two subtypes: β1 and β2
- Cholinergic
- synapse at which acetylcholine is released and binds to the nicotinic or muscarinic receptor
- Craniosacral System
- alternate name for the parasympathetic division of the autonomic nervous system that is based on the anatomical location of central neurons in brain-stem nuclei and the lateral horn of the sacral spinal cord; also referred to as craniosacral outflow
- Dual Innervation
- Both parasympathetic and sympathetic neurons connect to (or innervate) an organ (viscera); example, the heart is affected by both divisions of the ANS simultaneously
- Endogenous
- describes substance made in the human body
- Epinephrine
- signaling molecule released from the adrenal medulla into the bloodstream as part of the sympathetic response
- Exogenous
- describes substance made outside of the human body
- Fight-or-Flight Response
- set of responses induced by sympathetic activity that lead to either fleeing a threat or standing up to it, which in the modern world is often associated with anxious feelings
- G Protein–Coupled Receptor
- membrane protein complex that consists of a receptor protein that binds to a signaling molecule—a G protein—that is activated by that binding and in turn activates an effector protein/enzyme that creates a second-messenger molecule in the target cell
- Greater Splanchnic Nerver
- nerve that contains fibers of the central sympathetic neurons that do not synapse in the chain ganglia but project onto the celiac ganglion
- Lesser Splanchnic Nerve
- nerve that contains fibers of the central sympathetic neurons that do not synapse in the chain ganglia but project onto the inferior mesenteric ganglion
- Mydriasis
- dilation of the pupil; typically the result of disease, trauma, or drugs
- Muscarinic Receptor
- type of acetylcholine receptor protein that is characterized by also binding to muscarine and is a metabotropic receptor
- Nicotinic Receptor
- type of acetylcholine receptor protein that is characterized by also binding to nicotine and is an ionotropic receptor
- Norepinephrine
- signaling molecule released as a neurotransmitter by most postganglionic sympathetic fibers as part of the sympathetic response, or as a hormone into the bloodstream from the adrenal medulla
- Parasympathetic Division
- division of the autonomic nervous system responsible for restful and digestive functions
- Parasympathomimetic Drugs
- drugs that enhance or mimic the function of the parasympathetic system
- Postganglionic Fiber
- axon from a ganglionic neuron in the autonomic nervous system that projects to and synapses with the target effector; sometimes referred to as a postganglionic neuron
- Preganglionic Fiber
- axon from a central neuron in the autonomic nervous system that projects to and synapses with a ganglionic neuron; sometimes referred to as a preganglionic neuron
- Prevertebral Ganglia
- autonomic ganglia that are anterior to the vertebral column and functionally related to the sympathetic chain ganglia
- Reflex Arc
- circuit of a reflex that involves a sensory input and motor output, or an afferent branch and an efferent branch, and an integrating center to connect the two branches
- Rest and Digest
- set of functions associated with the parasympathetic system that lead to restful actions and digestion
- Somatic Reflex
- reflex involving skeletal muscle as the effector, under the control of the somatic nervous system
- Sympathetic Chain Ganglia
- series of ganglia adjacent to the vertebral column that receive input from central sympathetic neurons
- Sympathetic Division
- division of the autonomic nervous system associated with the fight-or-flight response
- Sympatholytic Drug
- drug that interrupts, or "lyses," the function of the sympathetic system
- Sympathomimetic Drug
- drug that enhances or mimics the function of the sympathetic system
- Target Effector
- organ, tissue, or gland that will respond to the control of an autonomic or somatic or endocrine signal
- Terminal Ganglia
- ganglia of the parasympathetic division of the autonomic system, which are located near or within the target effector, the latter also known as intramural ganglia
- Thoracolumbar System
- alternate name for the sympathetic division of the autonomic nervous system that is based on the anatomical location of central neurons in the lateral horn of the thoracic and upper lumbar spinal cord
Grant and Other Information
Except where otherwise noted, this work by The Community College Consortium for Bioscience Credentials is licensed under a Creative Commons Attribution 4.0 International License.
Text from BioBook licensed under CC BY NC SA and Boundless Biology Open Textbook licensed under CC BY SA.
Other text from OpenStaxCollege licensed under CC BY 3.0. Modified by Andrea Doub, M.S., Alice Rudolph, M.A. for c3bc.
Instructional Design by Courtney A. Harrington, Ph.D., Helen Dollyhite, M.A. and Caroline Smith, M.A. for c3bc.
Media by Brittany Clark, Jose DeCastro, Jordan Campbell and Antonio Davis for c3bc.
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