PNS Autonomic Plexuses Flashcards
The autonomic plexuses are primarily concerned with supply of ______________ in the ___________ and ____________ cavities.
visceral structures
thoracic
abdominopelvic
Fiber types include:
- parasympathetic - preganglionic, postganglionic
- sympathetic - preganglionic, postganglionic
- afferents - somatic, visceral
What is the main contribution to the esophageal plexus and where does the synapse occur?
main contribution is from vagus and recurrent laryngeal that synapse on postganglionic cells in wall of esophagus
What is the sympathetic contribution to the esophageal plexus?
sympathetic contribution is from greater splanchnic nerves, arising from the T5-T9 ganglia
What are the contributions to the thoracic aortic plexus?
- vagus nerve (sensory, visceral afferent)
- greater splanchnic nerve (sympathetic)
- T1-T5 sympathetic ganglia (vascular)
What is the primary component of the pulmonary plexus, how do they arrive at the plexus, and where does the synapse occur?
parasympathetics that arrive at the plexus via anterior and posterior bronchial branches of the vagus nerve. These preganglionic fibers synapse with postganglionic fibers in the wall of the bronchial vessels.
What does parasympathetic stimulation of the pulmonary plexus result in?
- bronchiole constriction
- increased glandular activity
Where do the sympathetic fibers that go to the pulmonary plexus come from and what do they supply?
sympathetic fibers to the pulmonary plexus are from T2-T4 ganglia. They supply the pleura, bronchial glands, and musculature.
What does the cardiac plexus supply?
- myocardium
- great vessels at base of heart
- coronary arteries
How do parasympathetic fibers reach the cardiac plexus and what does their stimulation result in?
Parasympathetic information arrives at the cardiac plexus via the superior and inferior cardiac nerves, branches of the vagus nerve. Their influence results in decreased heart rate and constriction of coronary arteries.
How do sympathetic fibers reach the cardiac plexus and what does their stimulation result in?
Sympathetic fibers arrive from the superior, middle, and inferior cardiac nerve and from the T2-T4 sympathetic ganglia. Their influence results in increased heart rate and dilation of the coronary vessels.
What is the largest prevertebral plexus?
celiac plexus
What vertebral level does the celiac plexus begin at?
L1
The celiac plexus is a dense gangliated plexus that forms a network around the __________________ and its branches down to and including the ___________ and ______________.
- abdominal aorta
- common iliac arteries
- median sacral arteries
What are the three pairs of well-defined ganglia associated with the celiac plexus?
- celiac ganglia, adjacent to celiac artery
- superior mesenteric ganglia, associated with the superior mesenteric artery
- aorticorenal ganglia, near renal arteries
Secondary plexuses associated with the celiac plexus are named for the ________ associated with each one.
arteries
What are the twelve secondary plexuses associated with the celiac plexus?
- phrenic plexus (inferior phrenic artery)
- left gastric plexus
- hepatic plexus
- splenic plexus
- superior mesenteric plexus
- suprarenal plexus (middle suprarenal artery)
- renal plexus
- gonadal plexus
- abdominal aorta plexus
- inferior mesenteric plexus
- superior hypogastric plexus
- inferior hypogastric plexus
The superior hypogastric plexus is part of the celiac plexus between the ____ and _____ vertebral levels. It incudes the _________ and _________ plexuses.
- L4 and S1
- abdominal aortic and inferior mesenteric plexuses
The inferior hypogastric plexus includes the celiac plexus below the __________________. It is the ______ largest prevertebral plexus.
- internal iliac artery
- second
What four secondary plexuses is the inferior hypogastric plexus associated with?
- vesicle
- prostatic or uterine/vaginal
- rectal
- cavernous
Defecation and micturition are initiated by _________ input.
parasympathetic
What type of fibers are sensitive to stretching of walls of bladder or rectum and initiate a stretch reflex?
visceral afferents
What type of fibers travel out to pelvic splanchnic nerves to detrusor muscle and/or rectal musculature?
efferents
Efferent fibers travel out to pelvic splanchnic nerves to ___________ and/or ___________. External sphincter muscles are relaxed.
- detrusor muscle
- rectal musculature
Efferent fibers travel out to pelvic splanchnic nerves to detrusor muscle and/or rectal musculature. ___________ muscles are relaxed.
external sphincter
