Autonomics Flashcards
what do autonomic plexuses contain?
Preganglionic parasympathetic fibers
Preganglionic sympathetic fibers
Postganglionic sympathetic fibers
Prevertebral sympathetic ganglia
what are the two sources of sympathetic innervation to the pelvis?
Lumbar splanchnic n.
Sacral splanchnic n.
(both preganglionic sympathetic)
what is the one source of PS innervation to the pelvis?
Pelvic splanchnic nn (preganglionic PS)
what do efferent sympathetics do?
vasoconstriction, contraction of sphincter muscle, inhibition of peristalsis, inhibition of glandular secretions
What does PS in pelvis do?
vasodilation, peristalsis, contraction of detrusor muscle of bladder and myometrial muscle of uterus
what does superior hypogastric plexus supply?
branche sto ureter and genital organs (epididymis, tesis, ovary)
what does inferior hypogastric supply?
- supplies pelvis
- supplies prostatic plexus, rectum, ureteral plexus, urterer, penis, prostate, ovary, bladder, vagina — pretty much everything in the pelvis
- it is a continuation of the superior hypogastric plexus via the hypogastric nn.
- located along the lateral surface of the rectum
- contains PS and symp fibers
pelvic splanchnic nn.
supply PS innervation and cell bodies are located in the IMLCC at S2-4
- pelvic splanchnic nn. distribute with the inferior hypogastric and subsidiary plexuses to the pelvic and perineal organs
- postbanglionic fibers are found in the wall of the organs
()/never come from sympathetic chains!!!)
ganglion impair
where the right and left sympathetic trunks merge
Lumbar splanchnic nn.
- preganglionic neurons located in IMLCC at T11-L2
- they enter sympathetic chain, do not synapse, and exit as lumbar splanchnics
- lumbar splanchnic nn. enter the intermesenteric and superior hypogastric plexuses and synapse with postganglionic neurons found there
- postganglionic neurons travel from the superior hypogastric plexus to the inferior hypogastric plexus via the hypogastric nn. - where they then spread to pelvis.
- ** this is the major route of symp innervation to the pelvis***
hypogastric nn.
postganglionic sympathetic fibers. connect eh syperior hypogastric plexus with the inferior hypogastric plexus
subsidiary plexuses
postganglionic fibers spread to pelvic viscera from inferior hypogastric lexuses via subsidiary plexus or fvia inferior hypogastric plexus itself
Sacral splanchnics
- ** minor route of symp. innervation to splanchnics***
- preganglionic cell bodies located in IMLCC at T12-L2
- these fibers descned within the symp. chain to sacral levels and exit without synapsing as sacral splanchnic nn.
- they enter the inferior hypogastric plexus where they synapse
- postganglionic fibers then spread to pelvic visceria via subsidiary plexus and inferior hypogastric plexus
What is perineal innervation?
PS: via cavernous plexus (continuation of uterovaginal/prostatic plexuses. cavernous nn. distribute with branches of pudendal nn.)
Symp: via pudendal n (S2,3,4)
provides autonomic innervation to erectile tissues, urethral mucosa and glands
Urinary bladder innervation
via inferior hypogastric plexus
Symp: T10-L2 via lumbar and sacral splanchnic nn. (results in contraction of trigonal muscle and smooth muscle portion of sphincter urethrae mechanism; vasomotor)
PS: S2-4 via pelvic splanchnic nn. (contraction of detrusor mm. and urination)
Urethra innervation
via inferior hypogastric plexus –> prostatic or vesicle plexus
Symp: via lumbar/sacral splanchnics (L1-L3)
PS via pelvic splanchnics (S2-4)
innervation of perineal urethrae provided via pudendal nn (S2-4)