The autonomic nervous system and pelvic viscera Flashcards
What is the autonomic nervous system distributed throughout
CNS and PNS
What is the autonomic nervous system divided into
Sympathetic and parasympathetic
What region is the parasympathetic nervous system associated with
Craniosacral region
What regions the sympathetic nervous system associated with
Thoracolumbar
What are the PNS neutrons divided into
Somatic sensory neurone
Somatic motor neurone
Autonomic motor neurone
What is the efferent pathway of autonomic nervous system
Autonomic motor neurone
Where are the preganglionic neurones situated in the autonomic motor neurone
Lateral Grey horn of spinal cord
Which cranial nerves contribute to the autonomic motor neurone
3,7,9,10
What is the role of the sympathetic division
Function to prepare body for an emergency:
- INcrease HR
- Redistribution of blood
- Increase BP
Where does the efferent outflow of the sympathetic division come from
Spinal cord, sympathetic trunk, branches, plexuses and ganglia
Where do preganglia that innervate head, thoracic viscera (foregut) come from
T1-T6
Where do preganglia that innervate abdominal viscera (midgut) come from
T7-T11
Where do preganglia that innervate pelvic viscera (hindgut) come from
T12-L2(3)
What is the course of preganglia
Come from lateral grey horn of spinal cord
Go to paravertebral ganglia of sympathetic trunk
Once reached, can do one of 4 things:
- Synapse at entry level
- Ascend and then synapse
- Descend and then synapse
- No synapse, form splanchnic nerves
How many ganglia are in the neck
3
How many ganglia are in the abdomen
4/5
How many ganglia are in the thorax
11/12
How many ganglia are in the pelvis
4/5
Where do the greater splanchnic nerves originate from
T5-T9
Where do the lesser splanchnic nerves originate from
T10-T11
Where do the least splanchnic nerves originate from
T12
where do the splanchnic nerves originate from
Thoracic sympathetic trunk
Where do the splanchnic nerves synapse
IN the abdominal region with the prevertebral ganglia
Where are the nerve cells of the parasympathetic nervous system located
Brainstem and sacral segments of the spinal cord
What are the cranial nerves 3,7,9,10 associated with
3-oculomotor
7-facial
9-Glossopharyngeal
10-vagus
What sacral segments of spinal cord do parasympathetic fibres come from
S2,S3,S4 (innervate pelvic region)
Role of sympathetic NS in digestion
Inhibits peristalsis
Constricts blood vessels to tract so blood available for skeletal muscles
Contracts internal anal sphincter
Role of sympathetic NS in urinary tract
Vasoconstriction of renal vessels
Contraction of internal sphincter of bladder
Role of sympathetic NS in genital tract
Ejaculation and vasoconstriction leading to remission of erection
Role of parasympathetic NS in digestive tract
Stimulates peristalsis and secretions of digestive juices
Contracts rectum
Inhibits internal anal sphincter
Role of parasympathetic nS in urinary tract
Inhibits contraction of bladder internal sphincter
Contract detrusor muscle of bladder wall (urination)
Role of parasympathetic NS in genital tract
Erection of erectile tissue of external genitals
What is the enteric nervous system and what is it split into
Extends around GI tract
Submucosal plexus (controls glandular secretion of mucosa)
Myenteric plexus )controls peristalsis)
What is Hirschsprung’s disease and symptoms
Absense of enteric neurone from variable lengths pf the distal gut
Intestinal obstruction or severe constipation
