14. ANS Phys Flashcards
Visceral sensory information is conveyed via the _____ in the medulla.
nucleus of the solitary tract
_____ such as propranolol are used to treat hypertension (high blood pressure) and coronary artery disease.
Beta-blockers
Axons pass through the spinal trunk to innervate postganglionic sympathetic neurons located in the ___ and _____.
celiac and mesenteric ganglia
____ ratio of pre- to post-ganglionic neurons in the SNS.
1:10
Postganglionic neurons exit the spinal trunk through the gray rami communicans (unmyelinated) and travel in the spinal nerves to reach?
sweat glands, peripheral blood vessels, hair follicles, etc
• Angiotensin II: – Constricts blood vessels – Acts on kidney to increase water retention – Activates neurons in ______
subfornical organ
The axons from the preganglionic neurons in the sacral portion of the parasympathetic system travel in the _____ to innervate ganglia associated with the colon, rectum, urinary bladder, and genital organs
splanchnic nerves
PNS neurons are located in the _____ (paravertebral chain ganglia).
ganglia of the sympathetic trunk
The β2 adrenergic receptor: Antagonist example?
Butaxamine
Acetylcholine is the neurotransmitter released by _____.
preganglionic sympathetic neurons
The nicotinic receptor is a _____ channel.
ligand-gated, non-selective cation
To counteract the bronchoconstriction that occurs in asthma or severe anaphylactic reactions, ____ or a more selective _____ is administered to initiate bronchodilation.
epi; β2 agonist
The ______ is a ligand-gated, non-selective cation channel.
nicotinic receptor
What is another name for an adrenergic receptor antagonist?
parasympathomimetic
There are two types of cholinergic receptors to which ACh binds and elicits a cholinergic response: ____ and _____.
nicotinic; muscarinic
The β1 adrenergic receptor: CV-related action of agonist? Agonist example?
Increased heart rate Dobutamine
There are two types of cholinergic receptors to which ____ binds and elicits a cholinergic response: nicotinic and muscarinic.
ACh
The α1 adrenergic receptor: - CV-related action of agonist? - Agonist example?
vasoconstriction in skin Phenylephrine
What is a cluster of cell bodies in the peripheral nervous system called?
a ganglion
____ ratio of pre- to post-ganglionic neurons in the PNS.
1:3
The postganglionic sympathetic neurons involved in regulation of the GI tract are located in the celiac and mesenteric ganglia. Their axons form the _____ innervating the abdominal viscera.
perivascular plexuses
In contrast to the somatic (motor) nervous system that controls skeletal muscle contraction, the autonomic nervous system is characterized by a _____ between the central nervous system (CNS) and the peripheral target organ.
two-neuron link
____ causes renin to be released from the kidneys.
Low blood pressure
Beta-blockers such as propranolol are used to treat _____ and _____.
hypertension (high blood pressure); coronary artery disease
1:10 ratio of pre- to post-ganglionic neurons in the ____ nervous system.
sympathetic
How are NE or ACh released?
exocytosis
Postganglionic neurons exit the spinal trunk through the ______ (unmyelinated) and travel in the spinal nerves to reach the sweat glands, peripheral blood vessels, hair follicles, etc.
gray rami communicans
The α2 adrenergic receptor: CV-related action of agonist? Agonist example?
Presynaptic inhibition of NE release; some vasoconstriction Clonidine
The _____ is organized in the medulla with afferent information transmitted in the glossopharyngeal nerve (cranial nerve IX).
baroreflex
The α2 adrenergic receptor: Antagonist example?
Trazodone
ACh acts on the nicotinic cholinergic receptors on postganglionic neurons and causes ____ and ____ of the postganglionic neuron.
depolarization; firing
The _____ of the parasympathetic nervous system are located in brainstem nuclei and in the sacral spinal cord.
preganglionic neurons
The parasympathetic, postganglionic neurons use ____ as their neurotransmitter and are characterized by short axons.
ACh
Axons pass through the spinal trunk to innervate _____ located in the celiac and mesenteric ganglia.
postganglionic sympathetic neurons
_____ acts on the nicotinic cholinergic receptors on postganglionic neurons and causes depolarization and firing of the postganglionic neuron.
ACh
The ____ exit the brainstem in cranial nerves III (oculomotor), VII (facial), IX (glossopharyngeal), and X (vagus).
parasympathetic preganglionic fibers
Transmission over the preganglionic fibers is relatively fast because they are composed of ______.
myelinated fibers
______ results in decreased heart rate and force of contraction.
Increased parasympathetic output
Mainly _____ receptors are present in the cell body of postganglionic neurons of the autonomic ganglia whereas _____ receptors are present on the effector cells of cardiac muscle, smooth muscle, and glands.
nicotinic; muscarinic
Low blood pressure causes renin to be released from _____.
the kidneys
The preganglionic neurons of the sympathetic nervous system are located in the ______ of the thoracic and upper lumbar segments of the spinal cord.
intermediolateral column
Mainly nicotinic receptors are present in the _____ whereas muscarinic receptors are present on the effector cells of _______.
cell body of postganglionic neurons of the autonomic ganglia ; cardiac muscle, smooth muscle, and glands
Increased parasympathetic output results in _____.
decreased heart rate and force of contraction
_____ are characterized by long axon, ACh, and they innervate postganglionic neurons in ganglia near the effector organs.
parasympathetic, preganglionic fibers