Exam 1 Flashcards
Alpha 1
Smooth M. contraction (vessels)
mydriasis (dilation of pupil)
vasoconstriction in skin, mucosa, GI
Sphincter contraction of GI tract and UB
Alpha 2
CNS effects
smooth muscle mixed effects
cardiac m. relaxation
Beta 1
Cardiac
Positive Chronotropic, Dromotropic, Ionotropic effects
Beta 2
Smooth muscle relaxant
Vessels, lungs
Epinephrine
Low doses: B1 agonist- vasodilation; decrease BP, increase HR
High doses: a1 premdominates- vasoconstriction; increase BP, increase HR at B1; bronchodilator at B1
Norephinephrine
alpha 1 agonist - BP increase (reflex decrease HR)
Dobutamine
Cardiac B1 agonist
txt: heart failure, cardiogenic shock, temporary AV block
Terbutaline
Beta 2 agonist
Beta 2 (bronchial, vascular, uterine smooth m.)
Bronchodilation (treats acute asthma)
Xylazine
alpha 2 agonist
sedative, emetic effect in cats
Phenylephrine
alpha agonist
decongestant
increase BP
CNS stimulation
unstable patients in shock- to increase BP
Isoproterenol
Beta agonist
vasodilation (decrease BP), increase HR; bronchodilator
hepatic elimination
Prazosin
alpha 1 antagonist
smooth muscle relax
Propranolol
Beta antagonist/blocker
anti-arrhythmic
-cardioprotective for cats with hyperthyroidism/HCM)
gradual withdrawal - bradycardia, hypotension
Atenolol
Beta 1 antagonist
anti-arrhythmic
gradual withdrawal
blocks Epi at cardiac B1
Phentolamine
alpha antagonist
vasodilation
treat hypertensive episode
Yohimbine
alpha 2 antagonist
increase BP, CNS, reverse Xylazine
Bethanechol
muscarinic cholinergic agonist
treat bladder atony (contracts bladder)
Gi stimulant
No CNS activity; less potent than carbachol
reverse with Atropine
Carbachol
Cholinergic agonist (M & N)
potent
effects of ACh
GI and urinary tract effects
Acetylcholine
Cholinergic agonist
Muscarinic and nicotinic
Atropine
Cholinergic muscarinic antagonist
blocks parasympathetic way
increase HR, bronchodilation effects
crosses BBB, CNS effects
Glycopyrrolate
Muscarinic antagonist
poor BBB penetration
similar to Atropine- less CNS effects, more potent
N-butylscopolammonium Bromide
Muscarinic antagonist
does not cross BBB
Anti-spasmotic for gas colic or rectal exam in horses
Edrophonium
Anticholinesterase- inhibit AChE so intensify effects of ACh
short acting
diagnose myasthenia gravis, temporary reversal of m. relaxant
Neostigme
Anticholinesterase
reversible, 1-3 hours
treats glaucoma, myasthenia gravis, ruminal stimulant