Autonomics Flashcards
a1 receptors
Gq protein coupled (DAG and IP3-> Ca)
Vascular smooth muscle contraction, pupil contraction (mydriasis), intestine and bladder sphincter contraction
a2 receptors
Gi coupled (inhibitory) Decrease sympathetic outflow (negative feedback presynaptic neurons) Increase platelet aggregation Decrease insulin, lipolysis Decrease aqueous humor production
B1 receptors
Gs coupled (excitatory)
Increase HR and contractility
Increase renin release
Increase lipolysis
B2 receptors
Gs coupled; Epi only Vasodilation, bronchodilation Decrease uterine tone Ciliary muscle relaxation Increase insulin release, lipolysis Increase aqueous humor production
B3 receptors
Gs coupled
Increase lipolysis
Increase skeletal muscle thermogenesis
M1 receptors
Gq coupled; parasympathetic
CNS, enteric nervous system
M2 receptors
Gi coupled; PS
decrease HR and atrial contractility
M3 receptors
Gq coupled; PS
Exocrine gland excretions
Gut peristalsis, bladder contraction, bronchoconstriction, pupil contraction (miosis), ciliary contraction (accommodation)
Cholinomimetic drugs-direct agonists
Bethanechol-bowel and bladder contraction
Carbachol-pupil constriction-open angle glaucoma
Methacholine-airway-asthma test
Pilocarpine-Exocrine excretion-xerostomia; ciliary and pupil constriction-open and closed angle gluacoma
Cholinomimetics-indirect agonists
Anti-cholinesterases-increase ACH
Donepezil, galatamine, rivastigmine-Alzheimers
Neostigmine-No CNS-reverse NMJ blockade, myasthenia gravis, ileus and urinary retention
Physostigmine-anticholinergic toxicity-crosses BBB
Pyridostigmine- gets rid of myasthenia gravis
Cholinergic Toxicity
Organophosphates
DUMBBELSS (leak everywhere)
Bronchosecretions-resp failure
Tx-atropine and pralidoxime (regenerate AChE)
Indirect sympathomimetics
Indirect general agonists, reuptake inhib, release stored catecholamines
Amphetamine-for narcolepsy, obesity, ADHD
Cocaine-vasoconstriction, local anesthesia
Ephedrine-nasal decongestion, urinary incontinence, hypotension
Muscarinic antagonists
Atropine, homatropine, tropicamide-eye Benztropine-Parkinson Glycopyrrolate-GI, resp Hyoscyamine, dicyclomine-GI-IBS Ipratropium, tiotropium-COPD, asthma Oxybutynin, solifenacin, tolterodine-GU-overactive bladder Scopolamine-CNS motion sickness
Sympathomimetics
Albuterol (acute), salmeterol (long) (B)-asthma, COPD
Dobutamine-HF
Dopamine-unstable bradycardia, HF, shock
Epinephrine-anaphylaxis, asthma, open glaucoma
Fenoldopam (D1)-HTN crisis
Isoproterenol (B)-evaluate tachyarrhythmias
Midodrine (a)-autonomic insufficiency and postural hypotension
NE-hypotension, septic shock
Phenylephrine (a)-hypotension, ocular procedures, rhinits
Sympatholytics- a2-agonists
Clonidine guanfacine-HTN urgency, ADHD, Tourette’s
a-methyldopa-HTN in pregnancy
