ch 16 - autonomic nervous system Flashcards
autonomic nervous sytem
Involuntary control of visceral effectors such as smooth muscle, glands, cardiac muscle, adipocytes
visceral motor neurons of ans
-preganglionic neurons
- postganglionic neurons
preganglionic neurons
Cell bodies in brainstem and spinal cord
- short in the sns, long in the psns
postganglionic neurons
Cell bodies in autonomic ganglia
- long in the sns, short in the psns
sympathetic division
fight or flight response
parasympathetic division
rest and digest
Thoracolumbar division
cell bodies of preganglionic neurons are in the lateral horns of the thoracic and lumbar sections of the spinal cord
preganglionic fibers characteristics
- short
- synapse w/ many postganglionic neurons
- release ACh
types of ganglia
sympathetic chanin ganglia
collateral ganglia
adrenal medullae
sympathetic chain ganglia
lie on each side of the vertebral column and control effects in thoracic cavity, head, neck, and limbs
collateral ganglia
anterior to vertebral column and innervate abdominopelvic tissues
celiac ganglia
a pair of interconnected masses of gray matter located at the base of that artery
superior mesenteric ganglion
near the base of the superior mesenteric artery, which provides blood to the stomach
inferior mesenteric ganglion
near the base of the inferior mesenteric artery,
adrenal medulla
modified sympathetic ganglion at the center of each adrenal gland
sympathetic activation
entire sympathetic division responds during a crisis
sympathetic preganglionic neurons releases
ACh
- these synapses are called cholinergic and are always excitatory
cholinergic vs adgrenergic
A: part of sympathetic nervous system
C: part of parasympathetic nervous system
varicosities
postganglionic neurons that branch into telodendria with segments that store neurotransmitters
most postganglionic neurons release
norepinephrine (NE)
adrenergic receptors
membrane G-protein coupled receptors that bind to NE and epinephrine
classes of adrenergic reactors
alpha (more sensitive to NE) and beta receptors
types of alpha receptors
alpha 1: more common, found in smooth muscle, has excitatory effect
alpha 2: has inhibitory effect, coordinates activities of the ANS
beta receptors
stimulation increases intracellular cAMP levels and triggers changes in metabolic activity
types of beta receptors
beta 1
beta 2
beta 3
beta 1 receptors
increase in metabolic activity in heart and muscles
beta 2 receptors
stimulation triggers relaxation of smooth muscles along respiratory tract
beta 3 receptors
stimulation leads to lipolysis, the breakdown of triglycerides in adipocytes
most sympathetic synapses at target organs are
adrenergic
craniosacral division of PSD (parasympathtic division)
cell bodies of preganglionic neurons are in the brainstem and lateral horns of the sacral segments of the spinal cord
terminal ganglion
near the target organ, usually paired
intramural ganglion
embedded in the tissues of the target organ
all parasympathetic neurons relase
ACh
cholinergic receptors
receptors for ACh in PSNS
types of cholinergic receptors
nicotinic receptors
muscarinic receptors
nicotinic receptors
parasympathetic receptor is found on ganglionic neurons and causes excitation
suprarenal medulla
endocrine gland that is innervated by the sympathetic division and is a modified sympathetic ganglion
whats located in the parasympathetic division
Long preganglionic fiber
Vagus nerve (CN X)
Pelvic nerves
Ganglia within target tissue
whats located in the sympathetic division?
Chain ganglia
Long postganglionic fiber
Thoracolumbar origins
Short preganglionic fiber
