Adrenergic System Flashcards
Sympathetic nervous system arises from
Thoracolumbar region
Important Amino acid need for the formation of Noradrenaline in neuron
Tyrosine
Rate limiting step in Noradrenaline synthesis
Conversion of Tyrosine to DOPA
Tyrosine hydroxylase - Rate limiting enzyme
Drug that inhibits Tyrosine hydroxylase enzyme
Metyrosine
VMAT-2 Receptors are present on
Present on Vesicles which is responsible for transportation of dopamine in vesicle
Example of VMAT-2 Inhibitors
Reserpine
New drugs - Tetrabenazine
Deutetrabenazine
Valbenazine
Drugs that inhibits entry of Noradrenaline in synapse
Guanethidine
Guanadrel
Drugs that prevents reuptake of Noradrenaline
Cocaine - increases sympathetic activity
Adrenergic receptors are classified into
Alpha receptors - Alpha-1 and Alpha-2
Beta receptors - Beta-1, Beta-2 and Beta-3
Alpha-1 receptors acts on
Blood vessels - Vasoconstriction
Eye - Mydriasis
Prostatitic urthera - contracts (decreases urine outflow)
Beta-1 receptors location and function
Heart - decreases HR (chronotropic), conduction (dromotropic) and Contractility (Inotropic)
JG cells of Kidney - Renin
Beta-2 receptors location and function
Lungs - Bronchodilation
GIT - Constipation
Bladder - Relaxes bladder - decrease urine outflow
BV - Vasodilation
Uterus - relaxes uterus
Skeletal muscles - can cause tremors
Liver - glycogenolysis, gluconeogenesis
Warning symptoms of Hypoglycemia
1) Tachycardia, Palpitations
2) tremors
3) Sweating
Why beta blockers are contraindicated in diabetes patient
Can mask warning symptoms of Hypoglycemia
Also can block the reversal
Sympathomimetic drugs can be divided into
Directly acting
Indirectly acting
Location and function of Beta-3 receptors
Lipolysis
Bladder - relaxes bladder
Beta-3 agonist used for overactive bladder
Mirabegron
Indirectly acting Sympathomimetics
Cocaine
TCA
Ephedrine
Pseudoephedrine
Amphetamine
Indirectly acting Sympathomimetics used as Nasal decongestants
Ephedrine
Pseudoephedrine
Effects of Amphetamine
Decreases sleep
Increase attention span
Amphetamine which is also termed as RAVE drug
Methylene dioxy methamphetamine
DOC For Narcolepsy
Modafinil
DOC for Attention deficit Hyperactivity Disorder (ADHD)
Methyl phenidate
Catecholamines can be divided into
Endogenous - Adrenaline, Noradrenaline, Dopamine
Exogenous - Dobutamine, Fenoldopam, Isoprenaline
Dopamine acts on which receptors
D1 - at low dose (<2mu/kg) - Vasodilation (max conc in Kidney)
Beta 1 - at intermediate dose (2-10)
Alpha-1 - at high dose (>10)
Uses of Dopamine
Acute CHF (2-10mu/kg)
Shock (>10)
DOC - if Shock+ Oliguria
Dobutamine acts on which receptors
Beta-1 receptors
Used in Acute CHF
Fenoldopam acts on which receptors
Only acts on D1 receptors - Vasodilation
Cam be indicated in Hypertensive emergency
Adrenaline, Noradrenaline and Isoprenaline acts on which receptors
Adrenaline - all receptors
Nor adrenaline - alpha -1, alpha-2, Beta-1
Isoprenaline - Beta-1 , Beta-2
What is effect of Noradrenaline on Heart rate
Decreases
Which drug cause maximum pulse pressure
Isoprenaline
Adrenaline can be used in
DOC In Anaphylactic shock i.m, 1:1000
Im Cardiac arrest while giving CPR
What happened when alpha blocker given to patient with adrenaline producing tumor
Can result in vasomotor reversal of dale (Because of only beta -2 action)
Alpha-1 agonist used as eyedrop for Fundoscopy
Phenylephrine
Alpha-1 agonist drugs used in treatment of Hypotension
Methoxamine
Mephentermine
Midodrine
Alpha-1 agonist used as nasal decongestant
Oxymetazoline
Xylomtazoline
Naphazoline
Alpha -2 agonist drugs
Clonidine
Methyldopa - used in treatment of Hypertension
Beta-2 agonist having tocolytic action
Ritodrine
Isoxsuprine
Beta-2 agonist given as inhalational route
Salbutamol
Salmeterol
Formoterol
Terbutaline
Alpha blockers can be divided into
Non selective alpha blocker
Selective alpha-1 blocker
Selective alpha-2 blocker - Yohimbine
Reversible non Selective alpha blockers are
Phentolamine
Tolazoline
Used in severe Hypertension
Can cause tachycardia
Short acting
DOC In Cheese reaction and Clonidie withdrawal
Phentolamine
Tolazoline
Irreversible Non Selective alpha blocker
Phenoxybenzamine - used in Pheochromocytoma
Selective alpha blockers
‘Zosin’
Prazosin
Terazosin
Doxazosin
Alfuzosin
Selective alpha blockers are used in
Mild to moderate hypertension
Benign prostatic hyperplasia
Peripheral vascular diseases
Scorpion sting
Selective alpha-1A blocker drugs including
Tamsulosin
Silodosin - not cause postural hypotension
Important side effect of Selective alpha -1 blockers
Orthostatic hypotension or Postural hypotension or First dose hypotension
Cardioselective beta blockers
New - Nebivolol
Beta - Betaxolol
Blockers - Bisoprolol
Acts - Acebutolol
Exclusively - Esmolol
At - Atenolol
Myo - Metoprolol
Cardium - Celiprolol
Beta blockers having intrinsic sympathomimetic activity
Contain - Celiprolol
Partial - Pindolol
Agonistic - Alprenolol
Activity - Acebutolol
Beta blockers having membrane stabilizing property
Black Na+ channels - local anesthetic property
Possess - Propranolol
Membrane stabilizing - Metoprolol
Or
Local - Labetalol
Anaesthetic - Acebutolol
Property - Pindolol
Water soluble Beta blockers
A - Atenolol
N - Nadolol
S - Sotalol
Longest acting beta blocker
Nadolol
Shortest acting beta blocker
Esmolol
Examples of third generation beta blockers
Any beta blockers that do Vasodilation (due to alpha blockade)
Labetalol
Carvedilol
Nebivolol
Cardiac indications of Beta blockers
Hypertension
MI
Angina
CHF
Arrythmia
HOCM
Extra cadiac indications of Beta blockers
Play - Performance anxiety
The - Thyrotoxicosis
G - Glaucoma
A - Akathisia
M - Migriane
E - Essential tremors
Contraindications of beta blockers due to beta-1 blockade
Decreases HR - sick sinus syndrome
Decreases conduction - AV blockade
Decreases contractility - Acute CHF
Contraindications of Beta blockers due to beta-2 blockade
Diabetes
Asthma
Peripheral vascular disease
Variant angina
Types of Glaucoma
Open angle glaucoma
Closed angle glaucoma
Cause of Open angle glaucoma
Inreased production of aqeuous humor
Cause of closed angle glaucoma
Obstruction in drainage of aqeuous humor
Aqueous humor is drained from
Trabecular outflow
Uveoscleral outflow
Drugs used to decrease formation of aqeuous humor
Alpha -1 agonist - vasoconstriction
Beta blockers
Carbonic anhydrase inhibitor
Alpha agonist used in glaucoma
Non selective alpha agonist - Adrenaline, Dipivefrine
Alpha-2 agonist - Apraclonidine , Brimonidine
Beta blockers used in Glaucoma
Timolol
Carteolol
Levobunolol - longest acting
Betaxolol
Avoided in asthma patients
Carbonic anhydrase inhibitor used in Glaucoma
Acetazolamide oral or iv
Brinzolamide
Dorzolamide - locally eye drops
Drugs that increase trabecular outflow in glaucoma
Miotics - Cholinergic agonist - Pilocarpine
Achesterase inhibitors - Physostigmine, Echothiophate
Side effects of Pilocarpine
Nasolacrimal duct stenosis
Side effects of Achesterase inhibitors
Cataract
Rho kinase inhibitors use in glaucoma
Netarsudil - acts by increasing outflow
Major side effect of Rho kinase inhibitors used in Glaucoma
Whorl like opacities in cornea/ Cornea verticillate
Drugs that increase uveoscleral outflow in glaucoma
Prostaglandins F2-alpha
Latanoprost
Bimatoprost
Travoprost
Tafluprost
Adverse effects of Miotics
Nasolacrimal duct stenosis
Cataract
Retinal detachment
Side effects of Beta blockers in Glaucoma
A - Asthma precipitates
B - Block - AV block
C - Acute CHF
D - Diabetes
Side effects of PGF2-Alpha
Fluid in macula(macular edema)
Pigmentation of iris (Heterochromia iridis)
Growth of eyelashes (Hypertrichosis)
Side effect of Apraclonidine
Lid retraction
Side effects of Brimonidine
Brain suppression - contraindicated in infants less than 2 years
Side effect of Adrenaline in Glaucoma
Adrenochrome - Conjunctival pigmentation
