Autonomic NS Flashcards
the sympathetic NS is also called the _______ division
thoracolumbar
where do the preganglionic neuron cell bodies originate in the sympathetic NS?
-lateral horns of the spinal segments T1-L2
synapses in the sympathetic NS can happen in 3 places. What are they?
1) sympathetic trunk
2) collateral ganglia
3) adrenal medulla
describe the sympathetic trunk synapse: sympathetic trunk
- longest tract
- runs right down side of spine
- ganglia are made up of fibres ascending or descending from T1-L2
describe the sympathetic trunk synapse: collateral ganglia
-3 ganglia (celiac, superior mesenteric, inferior mesenteric)
describe the sympathetic trunk synapse: adrenal medulla
- celiac ganglion - 1 really long pre-ganglionic neuron travels to adrenal medulla
- not traditional ganglia - synapses directly in organ itself
______ preganglionic neurons are shorter than post
sympathetic
______ preganglionic neurons are longer than post
parasympathetic
in the ______ NS, preganglionic neurons are myelinated and postganglionic neurons are not
sympathetic
what are the 3 collateral ganglia in the sympathetic trunk?
1) celiac (superior)
2) superior mesenteric
3) inferior mesenteric (inferior)
what is the function of splanchnic nerves?
carry info from preganglionic axons to collateral ganglia
what are the 3 splanchnic nerves?
- greater
- lesser
- lumbar
preganglionic axons synapsing to adrenal medulla pass directly through _____ ganglia
celiac
what body cavity do the celiac, superior and inferior mesenteric ganglia lie in?
abdominopelvic cavity
which 2 neurotransmitters does the adrenal medulla release?
epinephrine and norepinephrine
axons from what neurons innervate the adrenal medulla?
axons from preganglionic neurons that pass through the celiac ganglia
the parasympathetic nervous system is also referred to as the _____ division
craniosacral
which 4 cranial nerves do parasympathetic fibres originate from?
III, VII, IX, X
what portion of the brain do do the CNs that innervate parasympathetic fibres originate from?
III - midbrain
VII - pons
IX, X - medulla
all 3 regions of the brainstem
the largest amount of parasympathetic outflow comes from which CN?
vagus (X) (or cell bodies from sacral area
which has a more localized effects? sympathetic or parasympathetic division? why?
parasympathetic - because their preganglionic fibres are long so they release neurotransmitters closer to target organs/effectors
which parasympathetic neurons are found within the CNS?
preganglionic
where do the cell bodies of parasympathetic neurons lie?
ventral horn (different from sympathetic)
what are the 4 parasympathetic ganglia from superior to inferior?
- pterygopalatine
- ciliary
- submandibular
- otic
which neurotransmitters are released from the pre and postganglionic neurons from the sympathetic and parasympathetic NS?
parasympathetic:
- pre: ACh
- post: ACh
sympathetic:
- pre: ACh
- post: ACh/NE
visceral reflex - def
autonomic reflexes initiated by the viscera
-provide automatic motor responses that can be modified, facilitated, or inhibited by higher centres (especially hypothalamus)
describe the path of a long visceral reflex
1) stimulus stimulates receptors in peripheral tissue
2) impulse travels up afferent sensory fibre
3) processing center in SC (or brainstem)
4) impulse travels through preganglionic neuron
5) stimulation of autonomic ganglion (sympathetic or parasympathetic)
6) impulse travels through postganglionic neuron
7) response in peripheral effector
describe the path of a short visceral reflex
1) stimulus stimulates receptors in peripheral tissue
2) impulse reaches afferent sensory fibres
3) impulse reaches autonomic ganglion (sympathetic or parasympathetic)
4) impulse reaches postganglionic neuron
5) response in peripheral effector
DOES NOT REACH SC
