Phys: Autonomic Nervous System Flashcards
All preganglionic sympathetic and parasympathetic nerves release _________.
Acetylcholine
Postganglionic sympathetic nerves release ____.
Norepinephrine
Nerves that release norepinephrine are called ____ nerves
Adrenergic
Parasympathetic postganglionic nerves release _____.
Acetylcholine
nerves that release acetylcholine are called ______ nerves
Cholinergic nerves
Almost all postganglionic sympathetic nerves release norepinephrine except _____ _____, _______ muscles, and select ______ _____.
Sweat glands, piloerector muscles, and select blood vessels
Sympathetic preganglions are _____.
Short
Parasympathetic postganglions are _____.
Short
What does tone mean?
The basal rate of activity of each system
Sympathetic tone causes about a 50% _______.
Vasoconstriction
Increasing or decreasing tone can change _____ _____.
Vessel diameter
Parasympathetic tone provides background ___ _____.
GI activity
Dual innervation with ANS is
The two divisions working together to maintain homeostasis or get to get desired effect
To get maximal effect from either parasympathetic or sympathetic, what is required?
Full stimulation from one and full stop of stimulation by the other
Dual innervation of the pupil is
The size of the pupil being reciprocally controlled by sympathetic and parasympathetic
The pupil dilator muscle is innervated by
Sympathetic
The pupil dilator muscle is innervate by
Sympathetic
The pupil constrictor muscle is innervated by
Parasympathetic
Activation of ______ __ receptors cause constriction of the radial muscle, which causes dilation of the pupil
Alpha 1
Activation of pupil _______ receptors causes constriction of the sphincter muscle , which causes constriction of the pupil
Muscarinic
When the bladder is filling with urine, ____ control predominates
Sympathetic
When the bladder is full, _____ control predominates
Parasympathetic
What organs have ONLY sympathetic innervation
Sweat glands, vascular smooth muscle, pilomotor muscles of the skin, liver, adipose tissue, and kidney
Where is the control center of the ANS
Hypothalamus
what are the four adrenergic receptors?
alpha 1 and 2
beta 1 and 2
Alpha 1 receptors are for
activation
Alpha 1 receptors are located on
-smooth muscles
-GI and bladder
-pupillary dilator
Alpha 1 mechanism of action
Gq protein, stimulation of phospholipase C, and increase in inositol 1,4,5-triphosphate (IP3) and intracellular [Ca2+]
Alpha 2 receptors are for
inhibition
Alpha 2 receptors are located on
presynaptic nerve ending
Alpha 2 autoreceptors are located in
sympathetic postganglionic nerve terminals
Alpha 2 heteroreceptors are located in
platelets, fat cells, and the walls of the GI tract
Alpha 2 receptors are part of a ______ feedback loop with norepinephrine
negative
Alpha 2 mechanism of action:
Gi protein, inhibition of adenylate cyclase, and decrease in cyclic adenosine monophosphate(cAMP)
Beta 1 receptors produce
excitation
Beta 1 receptors are located in the
SA node, AV node, and ventricular muscle of the heart
Beta 1 mechanism of action
Gs protein, stimulation of adenylate cyclase, and increase in cAMP
Beta 2 receptors produce
relaxation
Beta 2 receptors are located on
vascular smooth muscle of skeletal muscle, bronchial smooth muscle, and in the walls of the GI tract and bladder
Beta 2 receptors mechanism of action:
Gs protein(note cute=kyle), simulation of adenylate cyclase
Beta 1 and 2 use the same
mechanism
What are the two types of muscarinic receptors
M2 and M3
M2 receptors are located in
the heart
M3 receptors are located in the
smooth muscle and glands
M2 receptors are _____ in the heart
excitatory
M3 receptors are ____ in the smooth muscle and glands
inhibitory
