Autonomic nervous system Flashcards

1
Q

How is the ANS defined anatomically and physiologically?

A

Anatomically: it is defined as all those neural pathways that leave the brain that do not innervate the volntary muscles

Physiologically: Homeostasis

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

What are the levels to the organisation of the nervous system?

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

Homeostasis can trigger two types of responses, what are they and the length of their effect?

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

What are the divisions of the ANS and what does each system help with?

A
  • Sympathetic: Fight or flight
  • Parasympathetic: Rest and digest
  • Enteric: sometimes considered part of the ANS and sometimes considered an independent system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the physiological roles of the ANS?

A
  • pupillary dilation
  • accommodation for near vision
  • dilation and constriction of blood vessels
  • force and rate of heartbeat
  • movements of the gastrointestinal tract
  • secretions from most glands
  • energy metabolism, particularly in liver and skeletal muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The point of contact between the first and second efferent neuron in the pathway pccurs in a neural structure called what?

A

A ganglion

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

What is a ganglion?

A

A group of nerve cell bodies that lie outside the central nervous system

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

With the sympathetic and parasympathetic nervous systems, tell me about the length of ganglion before and after the target tissue

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

How do drugs influence the ANS?

A

They mimic or block the effects of the two primary neurotransmitters, Ach and Noradrenaline/ adrenaline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Drugs that mimic neurotransmitters are referred to as what?

How do they effect receptors?

A

receptor agonists

These drugs activate receptors

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

Drugs that block neurotransmitters are referred to as what?

How do these effect receptors?

A

They are known as receptor antagonists

These drugs block the endogenous neurotransmitters from activating receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the sympathetic nervous system innervate?

Where is the preganglionic neuron located?

A

It innervates many different tissues

The preganglionic neuron is located in the midbrain, medulla or lateral horn of the spinal cord

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

What does the ganglia form in the sympathetic nervous system?

A

A sympathetic chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the sympathetic nervous system provide?

A

Provides diffuse innervation of target tissues

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

What does the parasympathetic nervous system innervate ?

Where is the preganglionic neuron located?

A

Located in meduall or sacral segment of the spinal cord

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

Where are the ganglia located in the parasympathetic nervous system?

A

In the target tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does the parasympathetic nervous system provide?

A

Discrete innervation of target tissues

18
Q

What is the role of the following:

  • Amygdala
  • Hypothalamus
  • Reticular formation
A
  • Amygdala: Main limbic region for emotions
  • Hypothalamus: Main integration center
  • Reticular formation: Most direct influence over autonomic function
19
Q

What do the postganglionic neurons to the smooth muslce in the kidney release?

Where are they located in the kidney?

A

In the renal vascular bed

release Dopamine

20
Q

What two organs are exceptions to the sympathetic nervous system?

A

Kidneys

Adrenal gland

21
Q

Tell me about the preganglionic neurons in the adrenal glands and what they release

A
  • Preganglionic neurons do not synapse in the paravertebral sympathetic ganglion
  • Preganglionic neurons synapse directly on the adrenal gland, release acetylcholine, and activate nicotinic receptors on the adrenal gland
  • Adrenal glands release adrenaline into systemic circulation
22
Q

Tell me the three important points about the ANS?

A

IMPORTANT POINT NO 1:

excitatory transmission at ALL the autonomic ganglia, sympathetic and parasympathetic, involves the transmitter Acetylcholine acting on Nicotinic acetylcholine receptors

IMPORTANT POINT NO 2:

transmission at the postganglionic sympathetic synapse usually involves Noradrenaline acting on either -adrenoceptor or -adrenoceptors

IMPORTANT POINT NO 3:

transmission at the postganglionic parasympathetic synapse usually involves Acetylcholine acting on Muscarinic receptors

23
Q

Overview of neurotransmission in the ANS

A
24
Q

For the following organ systems, describes the responses that the sympathetic and parasympathetic system would have on this organ

A
25
Q

What does the enteric nervous system consist of?

A

Neurons that regulate the gastrointestinal tract

26
Q

What does the enteric nervous system recieve inputs from?

A

It recieves inputs from the sympathetic and parasympathetic nervous system

It is neurochemically and functionally complex

27
Q

What does the enteric nervous system express?

A

A wide diversity of neurotransmitters

It expresses mechanoreceptors and chemoreceptors and is involved in local reflex pathways that regulate the activity of the gut independent of neural input from higher centres

28
Q

Dysautonomia or autonomic dysfunction usually is of what origin?

A

Usually of neuropathic origin: damage to autonomic nerves

29
Q

What are the diagnosis/ symptoms of dysautonomia or autonomic dysfunction?

A
  • dizziness and fainting upon standing up, or (or intolerance) orthostatic hypotension
  • an inability to alter heart rate with exercise
  • sweating abnormalities
  • digestive difficulties, such as a loss of appetite, bloating, diarrhea, constipation, or difficulty swallowing
  • urinary problems, such as difficulty starting urination, incontinence, and incomplete emptying of the bladder
  • sexual problems in men, such as difficulty with ejaculation or maintaining an erection
  • sexual problems in women, such as vaginal dryness or difficulty having an orgasm
  • vision problems, such as blurry vision or an inability of the pupils to react to light quickly
30
Q

Valvsalva, a physician and anatomist from bologna described the Eustachian tube and the maneuver to test what?

A

Its patency (openess)

Also described the use of this maneuver to expel pus from the middle ear

31
Q

With transmission at the post-ganglionic sympathetic synapse…

  1. what hormone is involved
  2. classification and pharmacology of receptors
  3. drugs that interfere with what
A

Transmission at the post-ganglionic sympathetic synapse

  1. synthesis, release, uptake and metabolism of noradrenaline
  2. classification and pharmacology of noradrenaline receptors
  3. drugs that interfere with post-ganglionic sympathetic transmission
32
Q

Tell me the following about transmission at cholinergic synapses in the ANS…

  1. synthesis and release of?
  2. ganglionic neurotransmission hormone?
  3. Post-ganglionic neurotransmitter hormone?
A
  1. synthesis and release of acetylcholine
  2. ganglionic neurotransmission, nicotinic receptors
  3. post-ganglionic neurotransmission, muscarinic receptors
33
Q

Draw a sympathetic organ synapse and label

A
34
Q

What was adrenaline identified from?

A

Adrenal extracts

35
Q

What was adrenaline shown to mimic?

A

sympathetic nerve stimulation

36
Q

What does the Finkelman preparation provide evidence for?

A

That the sympathetic nervous system releases an adrenaline like compound

37
Q

What did Von Euler demonstrate?

A

That noradrenaline is the main endogenous catecholamine in the sympathetic nerves

38
Q

The Finkel preparation

A
39
Q

Noradrenaline is the main transmitter at the post-ganglioic sympathetic synapse, except when?

A
  • in sweat glands (ACh, therefore atropine blocks sweating)
  • resistance blood vessels in skeletal muscle; activation of the sympathetic nervous system causes vasodilation in this tissue
  • n.b. there are other neurotransmitters (NANC, for non-adrenergic, non-cholinergic) these will be discussed later
40
Q

What is noradrenaline and what is its structure/ groups in the structure?

A

Noradrenaline is a Catecholamine