LP #102 Autonomic Nervous System Flashcards
ANS 2 division
- Parasympathetic
- Maintains homeostatic functional levels
- Rest & digest
- Sympathetic
- Stimulates emergency & high stress response
- Fight or Flight
ANS is _______ only?
Motor
NE (Norepinephrine) is secreted by most ____________ fibers
ACh (Acetylcholine) is segregated by ___________
- Sympathetic
* Parasympathetic
*Motor unit= ______ + ______ _____/_____
- Neurons
* Muscle cells/ glands
- 1 neuron & mm fibres it innervates
* neuron to mm (target organ)
Somatic
- 2 neurons in pathway
- pre-ganglionic neuron to ganglion
- synapse with post-ganglionic neuron that goes to target organ
ANS
- a.k.a Craniosacral division
- nurons originate in:
- brain stem & sacral region of SC
Parasympathetic division
Motor unit:
- pre-ganglionic fibres=
- ganglion=
- post-ganglion is fibres=
- Very long
- Close to target organ
- Very short; innervate target organ
Cranial outflow:
Parasympathetic signals leave brain stem via 1 of 4 cranial nn?
CN III (Oculomotor) CN VII (Facial) CN IX (Glossopharyngeal) CN X (Vagus)
- Sphincter mms of eyes
- Constriction of pupils
CN III Oculomotor
- Major secretory glands in head: lacrimal (eye), submandibular & sublingual
- innervates secretory cells of nasal mucosa
CN VII facial
-Parotid glad (salivary)
CN IX glossopharyngeal
- Extracranial course (extends into thorax)
- Largest parasympathetic nerve
- ~90% of parasympathetic Innervation
- Innervates internal organs
- exceptions: large intestine & pelvic organs
CN X vagus
4 key parasympathetic ganglia
- ciliary ganglia
- pterygopalatine ganglia
- submandibular ganglia
- otic ganglia
- Within orbits
- pre-ganglionic neurons are from Oculomotor nn (CN III)
Ciliary ganglia
- just posterior to maxillae
- pre-ganglionic neurons originate in pons (CN VII)
Pterygopalatine ganglia
- deep to mandibular angles
- pre-ganglionic neurons originate in pons
Submandibular ganglia
- just inferior to skull
- pre-ganglionic fibres are from glossopharyngeal nn (CN IX)
Otic ganglia
- Originates in sacral spinal cord segments S2-S4
- Nerves from pelvic splanchnic (visceral) nerves
- innervates distal 1/2 of large intestine & pelvic viscera
- synapse on ganglia close to target organs
Sacral outflow
