Autonomics Disease & Therapeutics Flashcards
How many nerves is the autonomic nervous system made up of?
2 neurons*Pre ganglionic, Post ganglionic
Where are the cell bodies of the Sympathetic nervous system found?
Thoracolumbar*Axons extend to para-pre vertebral ganglia so they are short
Post ganglionic neurons of the sympathetic nervous system extend from the para and pre vertebral ganglia to what?
Effecter tissues/organs
Where are the cell bodies of parasympathetic pre-ganglionic neurons found?
Craniosacral*axons extend to ganglia near effector tissue
Which system of the ANS uses ACh?
Both sympathetic and parasympathetic pre-ganglionic fibers
What type of receptors does ACh act on in post-ganglionic fibers?
Nicotinic
What three main transmitters are used for sympathetic post-ganglia?
1-Dopamine2-Norepi3-Epi*Most use NE
NE and EPI act on what and are released by what?
-Act on A and B receptors-Released by adrenal gland
What does DA mainly activate?
D1
What transmitter do post ganglionic parasympathetic neurons use?
ACh*acts on muscarinic receptors in effector tissues or nicotinic in somatic muscles
What three drugs are agonists to the three main muscarinic receptors?
1-ACh2-bethanechol (GI motility and secretion)3-Pilocarpine (glaucoma)
What tissue is the M1 receptor present in?
Stomach*increases acid secretion
What 4 tissues are M2 receptors found in?
1-Sinoatrial node (Slows HR)2-Atria (Slows AP duration and contractility)3-AV node (Slows conduction velocity)4-Ventricle (Slows contractility
What 2 tissues are M3 receptors found in?
1-GI smooth muscle (contract)2-Secretory glands (increase secretion)
What are the 2 antagonists of muscarinic receptors?
1-Atropine (antidote for nerve gas)2-scopolamine (motion sickness)
What is the agonist for Nicotinic receptors?
ACh
Where are Nm and Nn receptors respectively found?
Nm-Neuromuscular junctionNn-autonomic ganglia, adrenal medulla, CNS
What are the two antagonists for Nm receptors and the main antagonists for Nn receptors?
Nm- succinylcholine (depolarizing), d-tubocurarine (competes with ACh)Nn-mecamylamine
Which cholinesterase inhibitor has a short duration, is used for glaucoma, and is the antidote for atropine?
Physostigmine
Which cholinesterase inhibitor has extended duration and is used to treat alzheimer’s?
Donepezil (Aricept)
Which cholinesterase inhibitor is irreversible, has long duration of action and is used in nerve gas?
Sarin
What prevents release of ACh and used to relax intraocular muscles, treats muscle dystonia (spasms) and removes wrinkles?
Botulinim toxin
What are 2 cholinergic agents used in dentistry?
1-Cevimeline (evoxac) for xerostomia in Sjogrens2-Pilocarpine (salagen) xerostomia after radiotherapy
What are the 3 main agonists of a1 receptors of the sympathetic nervous system?
1-Epi (most)2-NE3-Phenylephrine
What are the 4 main agonists of a2 receptors of the sympathetic nervous system?
1-Epi (most)2-NE3-clonidine4-guanfacine
What are the 3 main tissues that contract or constrict when a1 receptors are activated?
1-Radial muscle of iris2-genitourinary and GI sphincters3-Vasculature
What are the 3 main tissues that are effected by a2 receptor activation?
1-Vasculature (constrict)2-NE terminals (decrease NE release)3-Brainstem (decrease NE release)
What is the main antagonist of the a1 receptor in the sympathetic nervous system?
Prazosin (treat hypertension)
What are the 3 agonists of B1 receptors?
1-Epi2-NE3-Isoproterenol
What are the 5 agonists of B2 receptors?
1-Epi (Most)2-NE3-isoproterenol4-albuterol (asthma)5-terbutaline
What 5 tissues have B1 receptors?
1-SA node (increase HR)2-Atria (increase contract velocity)3-AV node (increase conduction)4-HIS-Purkinje fibers (increase conduction)5-Ventricles (increase conduction/contraction)
What is the main antagonist of B1 and B2 receptors?
Propranolol
What 4 tissues have B2 receptors?
1-ciliary muscle (relaxation for far vision)2-Vasular (relax/vasodilate)3-Lungs (relax)4-Urinary bladder/uterine wall (relax)
In the kidney, what does DA released from sympathetic nerve terminals do?
Increase renal blood flow
What is haloperidol used to treat?
Schizophrenia*is a D2 antagonist
Which receptors does Epinephrine work on?
B1=B2a1=a2
How does Epi effect the Cardiac system?
Increases HR and increases strength of ventricular contraction via B1 receptor
How does Epi effect vasculature?
-Low dose=decrease in TPR and diastolic pressure-high dose=increase TPR and BP
How does Epi effect respiration?
Relaxes smooth muscle of airways and dilates bronchioles
How does Epi effect the eyes?
Dilates (mydriasis)*also increases outflow of aqueous humor
How does Epi effect genitourinary?
Relax detrusor muscle and uterus, contracts bladder sphincter
What are 5 main therapeutic uses of Epi?
1-Bronchospasm2-Anaphylaxis3-Restore function in cardiac arrest4-Treat open-angle glaucoma5-Prolong local anesthetics
What are 3 side effects of Epi?
1-Cardiac (increase HR, palpitations, arrhythmias, anginal pain)2-Vascular (increase TPR and BP lead to pallor)3-Respiratory (increase TPR leading to pulmonary edema)
What receptors does Norepinephrine act on?
Both a and B*B1 more than B2
What is the physiological effect of NE?
Vasoconstriction, increase TPR and BP
What is the main therapeutic use for NE?
To treat shock*increases BP to get blood to all organs
What are 3 main side effects of NE?
1-Slow Heartbeat if BP increases (baroreceptors)2-Forceful beat (B1)3-Vasoconstrict (less blood to vital organs, a1)
Depending on the dose, what three receptors does Dopamine act on from most to least?
1-DA2-B3-a
What are three responses that Dopamine elicits?
1-Increases BP and TPR via a12-Increases HR via B13-Increases organ perfusion via D1
a1 agonists, such as Phenylephrine have what 3 effects?
1-Vasoconstriction and increase TPR2-Decreased HR3-Constrict Sphincter muscle of bladder
a2 agonists such as clonidine and guanfacine have what 3 effects?
1-Bradycardia in some2-Dry mouth3-decrease sympathetic output when stimulating CNS a2
What are the two main uses for a2 agonists such as clonidine and guanfacine?
1-hypertension2-attention-deficit hyperactivity disorder
B agonists such as isoproterenol, albuterol and terbutaline are used for what 4 things?
1-Asthma2-bronchospasm3-COPD4-OBGYN (relax uterine smooth muscle to slow contractions)
Mixed agonists such as ephedrine, ephedra and pseudoephedrine release NE and are mainly used in what two things?
1-Decongestants2-Dietary supplements
What are 3 side effects of Mixed agonists?
1-Increased HR2-Vasoconstriction3-Dilate airways*can also be a stimulant if penetrates CNS
Which hormone is an emergency hormone secreted in response to stress?
Epinephrine*a1=a2, B1=B2
What three main things does Epinephrine do?
1-Increase HR2-arteriole constiction in abdomen (a1) dilate pre-capillary resistance in skeletal muscle (B2)3-Increase TPR (if fast and high, a1)
Which hormone is for routine cardiovascular control?
Norepinephrine*A1=A2, B1>B2
The most common form, which glaucoma develops over time and is treated with epinephrine to decrease production of aqueous humor?
Open-angle glaucoma
Which form of glaucoma causes a blocked drainage and results in a sudden rise in intraocular pressure?
Angle-closure glaucoma*treat with pilocarpine to pull iris open and release trabecular meshwork
What are 4 other indirect adrenergic agents?
1-Amphetamine2-Cocaine3-Methylphenidate4-TCAs
Which other adrenergic agent releases DA and NE?
Amphetamine
Which other adrenergic agent blocks the reuptake channels?
Cocaine
Which other adrenergic agent blocks reuptake of dopamine?
Methylphenidate
Which other adrenergic agent blocks reuptake of NE and Serotonin?
TCA’s
Which type of patient should you be worried about Tyramine filling up vesicles and depleting NE?
Those taking MAO inhibitor
Non-selective a Antagonists such as phenoxybenzamine and phentolamine have what two main effects?
1-Decrease TPR (thus decrease BP)2-Increase HR (baroreceptor response to decreased BP)
What are 2 side effects of non selective a antagonists such as phenoxybenzamine and phentolamine ?
1-Orthostatic hypotension2-Nasal Stuffiness
A1 antagonists such as Prazosin have what effect?
Vasodilation and thus decreased TPR and BP*used for hypertension and benign prostatic hypertrophy
Beta antagonists (blockers) such as propranolol (B1 and B2) and Atenolol (B1) have what 6 effects?
1-Cardiac (decrease HR and contractility)2-Vascular (increase TPR)3-Renal (decreased renin release)4-Respiratory (bronchial constriction)5-Metabolic (decrease glycogenolysis)6-Decrease aqueous humor
Cholinomimetic agents such as cholinesterase inhibitors, bethanechol, pilocarpine and nicotine are used to treat what 4 conditions?
1-Myasthenia graves2-Glaucoma3-Alzheimer’s4-Smoking cessation
Antimuscarinic agents such as atropine and scopolamine are used to treat what 4 things?
1-Parkinsons (adjunct)2-Motion sickness3-COPD4-Urinary urgency
What are 5 effects of Antimuscarinic agents such as atropine and scopolamine?
1-Dry mouth2-Constipation3-Blurred vision4-Sedation5-Urinary retention