Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology for Anaesthetists > Neurophysiology - Autonomic Nervous System > Flashcards

Neurophysiology - Autonomic Nervous System Flashcards

1
Q

Where do pre-ganglionic sympathetic nerves synapse

A

The sympathetic chain: Paravertebral ganglia

OR

Prevertebral ganglia

  1. Coeliac ganglion
  2. Superior mesenteric ganglion
  3. Inferior mesenteric ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is the sympathetic chain divided

A

Cervical –> head and neck

Thoracic

  • -> upper (T1 - T5) –> heart / lungs / aorta
  • -> Lower (T6 - T12) –> Foregut / midgut viscera

Lumbar
–> hindgut viscera

Sacral
–> Pelvic viscera

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference between the grey and white rami communicantes? Describe the origin, course and destination of the pre-ganglionic and post-ganglionic fibres of the SNS.

A

Ramus communicantes = nerve that connects two other nerves = communicating branch

These are the nerves that connect the dorsal and ventral nerve roots to the paravertebral sympathetic chain.

WHITE rami communicante

  • Pre-ganglionic SNS neurons ENTER SNS ganglia from the LATERAL HORN of grey matter in spinal cord via the ventral nerve root
  • Myelinated B fibers
  • Situated away from SC
  • Attached with thoracolumbar spinal nerves

GREY rami communicante

  • Post-ganglionic SNS neurons EXIT SNS ganglia toward target organ (SM, sudomotor, errector pili) via the dorsal and ventral rami
  • Unmyelinated C fibres
  • Situated near SC
  • Attached with all spinal nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the 3 exceptions to the: pre-ganglionic release of Ach and postganglionic release of NA

A
  1. Adrenal glands
    - -> Adrenal glands are directly innervated by pre-ganglionic neurons
    - -> Adrenal glands are effectively a modified sympathetic ganglion
  2. Eccrine Sweat glands are cholinergic SNS neurons (Ach released from post-ganglionic neurons)
  3. Metarterioles are SNS cholinergic fibres which cause functional arteriovenous shunting on skeletal muscle beds to prevent increases in MAP at the onset of exercise.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the Stellate ganglion and name SNS ganglia above T1

A
  1. Superior cervical SNS ganglion + T1 ganglion = Stellate ganglion
  2. Middle cervical SNS ganglion
  3. Inferior cervical SNS ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Stellate ganglion blockade used for?

A

SNS has been implicated in the development of chronic neuropathic, vascular and visceral pain.

Used to treat sympathetically mediated pain of the upper limbs
E.g.
–> Raynaud’s syndrome
–> Complex Regional Pain Syndrome (CRPS)
–> Rx hyperhidrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When would a Coeliac be performed and why

A

SNS has been implicated in the development of chronic neuropathic, vascular and visceral pain.

Pain associated with - Pancreatic carcinoma / chronic pancreatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When would a lumbar sympathectomy be performed and why

A

Used for diagnosis and treatment of sympathetically mediated pain of the lower limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the anatomy and distribution of the SNS

A

THORACOLUMBAR outflow

Superior cervical ganglion
Middle cervical ganglion
Inferior cervical ganglion
Paravertebral SNS chain (T1 --> L2/3)
Prevertebral ganglia
1. Coeliac
2. Superior mesenteric ganglion
3. Inferior Mesenteric ganglion
Adrenal Glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the anatomy and distibution of the PSNS

A

CRANIOSACRAL outflow
Cranial nerves: 3, 7, 9 and 10
–> supply upper half of body = Head to junction midgut and hindgut which is before the splenic flexure of the transverse colon

Spinal nerves: S2, S3, S4
Supplies the viscera of the lower half of the body from splenic flexure onwards.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the structure, location and function of the Nicotinic Ach receptor

A

Struction and funciton:
Ionotropic receptor with a central ion channel made up of multiple subunits. When Ach binds, the conformation changes, opening the channel and allowing the movement of cations down their concentration gradients.

Location:

  1. NMJ
  2. Autonomic ganglia
  3. Brain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why are nicotinic ACh receptors so named

A

Nicotine also acts as an agonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Differentiate:

  1. Fetal NMJ ACh nicotinic receptor
  2. Adult NMJ Ach nicotinic receptor
  3. Autonomic ganglia nicotinic receptor
A
  1. Fetal NMJ ACh nicotinic receptor - a2Bgd
  2. Adult NMJ Ach nicotinic receptor - a2Bed
  3. Autonomic ganglia nicotinic receptor - a2B3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why are muscarinic receptors so named

A

As the fungal alkaloid muscarine also acts on these receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of receptor is the Muscarinic receptor. How many subtypes are there and where are they found

A

Metabotropic G protein coupled receptor

5 types

HEAD - M1 (CNS and Secretory glands e,g, saliva)
HEART - M2 (Heart)
LUNGS/VESSELS - M3 (Smooth muscle of bronchioles and arterioles)
BRAIN - M4 and M5 (CNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of receptors are alpha 1 adrenoreceptors, where are these found and name common agonists and antagonists.

A

Gq protein coupled receptors –> activates phospholipase C –> Increased DAG and IP3 –> increases intracellular Ca2+

Found: Arteriolar smooth muscle and urethral sphincter.

Agonists: Phenylephrine, metaraminol, noradrenalin
Antagonists: Doxazosin, tamsolusin (HPT/BPH)

17
Q

What type of receptors are alpha 2 adrenoreceptors, where are these found and name common agonists and antagonists.

A

Pre-synaptic Gi coupled adrenoreceptors –> inactivates adenylate cyclase –> reduced IC cAMP –> reduced IC calcium.

Found: CNS, pancreas, arterioles

Agonists:

  1. Adrenalin and noradrenalin
    - -> Vasodilatation
    - -> Inhibition of insulin release from pancreas
    - -> Sedation and analgaesia
  2. Clonidine and Dexmedetomidine
    - -> Sedation and analgaesia
18
Q

What type of receptors are Beta 1 adrenoreceptors, where are these found and name common agonists and antagonists.

A

Gs coupled adrenoresptors –> activate adenylase cyclase –> increase cAMP –> Increase IC ca2+

Found: Heart and kidney

Agonists:
Adrenalin and Noradrenalin
–> Positive inotropy and positive chronotropy
–> Renin secretion

Antagonists:
Bisoprolol
–> Reduce myocardial contractility and heart rate in ischaemic heart disease

19
Q

What type of receptors are Beta 2 adrenoreceptors, where are these found and name common agonists and antagonists.

A

Gs coupled adrenoresptors –> activate adenylase cyclase –> increase cAMP –> Increase IC ca2+

Found: Smooth muscle: Bronchiole and Uterus

Agonist

  1. Adrenalin –> bronchodilatation and Uterine relaxation
  2. Salbutamol –> B2 agonist (Asthma/Tocolysis)
20
Q

Define the autonomic nervous system

A

A complex involuntary homeostatic control system with neurohumoral effects to maintain optimal body and organ function in response to internal and external triggers.

Facilitates the fight or flight and rest and digest responses

Physiology for Anaesthetists (61 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions