Autonomic Innervation of the Eye Flashcards
Ciliary muscle control
parasympathetic
Mydriasis
contracts pupillary dilator muscle
alpha-1 receptor NE
Alpha-1 receptor agonist use
pupillary dialation
Superior tarsal muscle receptor
alpha-1 receptor NE
Parasympathetic receptor type
mAChR
What muscle contracts in parasympathetic innervation of the eye?
ciliary muscle contraction
pupil constricts
Sympathomimetics
mimic sympathetic effects
Parasympathetic antagonist: the classic
atropine
Atropine
parasympathetic antagonist
What is the mechanism of cocaine with regards to the eye?
blocks neuronal reuptake of NE
keeps pupil dialated
What is the mechanism of amphetamines with regards to the eye?
promotes fusion of NE vesicles
Pathophys of Horner’s syndrome?
CNS/PNS damage to sympathetic nerve
What is phenylephrine?
alpha-1 agonist
Phenylephrine use
eye dilation
You give cocaine and the pupil dilates, what does that mean?
sympathetic innervation is intact
You give amphetamines and the pupil dilates, what does that mean?
postganglionic nerve is intact
You give cocaine and the pupil does not dilate but amphetamines do dilate pupil, what does that mean?
uh-oh
you probably cut the postganglionic sympathetic nerve
Where are nAChR located in sympathetic response?
cell bodies of postganglionic sympathetic and parasympathetics*
Pilocarpine
muscarinic antagonist
If eye does not respond to pilocarpine, where is the problem?
in the eye
If eye does respond to pilocarpine with miosis, where must the problem be?
third nerve palsy
What sympathetic receptor does the ciliary muscle use and what is the sympathetic response?
beta-2 receptor for NE
response is ciliary muscle relaxation
What sympathetic receptor does the superior tarsal muscle use and what is the sympathetic response?
alpha-1 receptor for NE
contraction of muscle, eyelid opening
Action of phenylephrine
direct stimulation of alpha-1 androgenic receptors
What is latanoprost and what is it used for?
prostaglandin derivative
Tx of glaucoma
Acetazolamide mechanism of action in glaucoma
CA inhibitor
protons cannot be used to exchange for Na+ from blood that can be used to pump into aqueous humor