Neural Control of Pelvic Function 4 Flashcards
Describe the levels of CNS control of micturition and defecation, differentiating reflexive and voluntary control mechanisms.
1
Q
What is the detrusor motor nucleus?
A
- Not locus of voluntary control
- Used to switch between sympathetic and parasympathetic stages - used for coordination
- means by which voluntary control is exerted
- reciprocal connections with other parts of the brain
2
Q
What are the lower levels of neural control of the bladder and colon?
A
- Sympathetic preganglionic neurons are located in the intermediolateral (IML) cell column in the T11-L2 segments.
- Sympathetic postganglionic neurons are located in the inferior mesenteric ganglia (IMG).
- Parasympathetic preganglionic neurons are located in the sacral parasympathetic nucleus (SPN) of the S2-S4 segments.
- Pudendal motoneurons are located in Onuf’s nucleus in the ventral horn of S2-S4 segments.
- Visceral and somatic afferents from pelvic structures travel in the pelvic, pudendal, and to a lesser extent, hypogastric nerve.
- They innervate spinal cord neurons in the dorsal horn, and bilaterally in the dorsal gray commissure (DGC).
