Exam 2: Analgesics 5: Alpha 2 agonists Flashcards
What are the 2 Alpha 2 agonists
- Dexmedetomidine
2. Xylazine
What are the 2 Alpha 2 antagonists
- Atipamezole
2. Yohimbine
What parts of the Nociception pathway do Alpha 2 agonists act on?
- Perception
- Modulation
- Transmission
Where are alpha 2 receptors located?
Brain and sC
What effect does a2 receptors have on insulin
Dec.
What effect does a2 receptors have on renin
dec
What effect does a2 receptors have on NE release
Dec
What effect does a2 receptors have on Pancreatic secretions
Dec
What is the most selective a2 agonist
Dexmedetomidine
Which a2 agonist has the fastest onset but shortest duration
Xylazine
T/F. A2 receptors are both sedatives and analgesics
T
what is the moa of a2 agonists
Competitive agonism of a2 receptors
What is the MOA of a2 agonists on the ANS?
competitive agonism of a1 receptors causing vasoconstriction
T/F. a2 agonists can cross the BBB
T
What are the 4 main effects of a2 agonists on the CNS
- sedation
- Pain modulation
- M relaxation
- Emesis
what is the emetic of choice for use in cats
Xylazine
What are the 2 phases of the CVS effect of a2 agonists
- Peripherial phase
2. Central phase
What happens in the peripheral phase?
Peripherial vasoconstriction leading to bradycardia
What receptors mediate the peripheral phase?
a1
What receptros mediate the central phase
a2
What happens in the central phase?
dec. symphathetic tone leading to peripherial vasodilation. causing bradycardia and hypotension
CO can dec. ____% with a2 agonists
30-50
a2 agonists cause a dec. CO due to an inc.____
BP and reflex bradycardia
T/F. all CVS effects due to a2 agonists are reversible
T
T/F. a2 agonists may cause abortions in ruminants
T
Specific competitive antagonist of Dexmedetomidine
Antipamezole
Specific Competitive antagonist of xylazine
Yohimbine
T/F. a2 antagonists only reverse sedative effects
F. will reverse sedation and analgesia
