alpha-2 agonists Flashcards

1
Q

what are the 3 subtypes identified based on susceptibility to activation/inactivation by agonists and antagonists and confirmed by molecular biology

A
  • a-2A: sedation, hypnosis, analgesia, sympatholysis
  • a-2B: vasocontriction, anti-shivering action, analgesia
  • a-2c: learning, startles response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what type of receptor is an a-2 adrenoceptor

A

G-protein coupled receptor

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

location of a-2 adrenoceptors

A

each receptor subtype is distributed ubiquitously throughout the body

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

presynaptic a-2 adrenoceptors

A

inhibit release of norepinephrine

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

postsynaptic a-2 adrenoceptors

A

norepinesphrine effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

a-2A receptors located presynaptically on neurons in the:

A

locus coeruleus

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

how is hyperpolarization mediated

A

by G-protein

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

what is the decreased sympathetic activity of a-2A

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

supraspinal level analgesic effects

A

activation of descending antioceptive pathways

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

spinal level (dorsal horn spinal cord)

A

pre/postysnaptic inhibition of nociceptive transmission

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

a-2 agonists vasocontriction effect

A
  • hypertension, reflex bradycardia, cause decrease CO
  • initial phase
  • no atropine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

a-2 agonists - decreased sympathetic tone

A
  • hypotension, direct bradycardia, cause decrease CO
  • secondary phase
  • yes atropine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

a-2 agonists - increased vagal tone

A

direct bradycardia, AV block

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

causes of medetomidine in dogs

A
  • increase in systemic and pulmonary artery pressure
  • decrease in HR (20-30%)
  • decrease in CO (50%)
  • increase in systemic and pulmonary vascular resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do anticholinergics cause (bad)

A
  • decrease in bradycardia
  • arrhythmias
  • hypertension
  • decreased contractility, impaired myocardial oxygenation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

are there respiratory effects of a-2 agonists in dogs, cats, humans, rats

A

no

17
Q

a-2 agonists respiratory effects in horses

A
  • decreased abduction of left arytenoid cartilage
  • affected the recurrent laryngeal neuropathy grade

normal horses