-
Forskolin
Activates adenylyl cyclase and raises intracellular cAMP
-
Quinidine
- Class 1A antidysrhythmic: Blocks voltage gated Na channels
- Increases AP duration
- Intermediate rate of association/dissociation
-
Procainamide
- Class 1A antidysrhythmic: Blocks voltage gated Na channels
- Increases AP duration
- Intermediate rate of association/dissociation
-
Class 1A antidysrhythmics (2)
classification
- Blocks voltage gated Na channels
- Increases AP duration
- Intermediate rate of association/dissociation
- Quinidine and Procainamine
-
Lidocaine
- Class 1B antidysrhythmic: Blocks voltage gated Na channels
- Decreases AP duration
- Fast rate of association/dissociation
-
Class 1B antidysthymic
- Blocks voltage gated Na channels
- Decreases AP duration
- Fast rate of association/dissociation
- Lidocaine
-
Flecainide
- Class 1C antidysrhythmic: Blocks voltage gated Na channel
- Same AP duration
- Slow rate of association/dissociation
-
Class 1C antidysrhythmic
- Blocks voltage gated Na channels
- Same AP duration
- Slow rate of association/dissociation
- Flecainide
-
Propanolol
- Class II antidysrhytmic: Sympathetic antagonist (beta blocker)
- Will also releive hypertension, but damp down sympathetic activity that occurs during a heart attack
- Acute IV: decrease CO -> compensatory increase in TPR. this goes away after a while, causing a long term decrease in BP
-
Atenolol
- Class II antidysrhythmic: Sympathetic antagonist (beta blocker)
- Will also releive hypertension, but damp down sympathetic activity that occurs during a heart attack
-
Class II antidysrhythmics (2)
- Propanolol and AtenololBeta blockers
-
Amiodarone
- Class III antidysrhythmic: Prolongs AP and refractory period
- Under different conditions can block both inward (Na) and outward (K) currents
- For ventricular dysrhythmias and re-entry that doesn't respond to class I
-
Class III antidysrhythmic
- Amiodarone
- Prolongs AP and refractory period
- Under different conditions can block both inward (Na) and outward (K) currents
- For ventricular dysrhythmias and re-entry that doesn't respond to class I
-
Verapamil
- Class IV antidysrhythmic: Ca channel blocker
- Acts primarily on nodal tissue (as AP highly dependent on L and T type Ca channels
- Slow conduction rate, prolong refractory period
- Can compromise excitation-contraction coupling
-
Diltiazem
- Class IV antidysrhythmic: Ca channel blocker
- Acts primarily on nodal tissue (as AP highly dependent on L and T type Ca channels
- Slow conduction rate, prolong refractory period
- Can compromise excitation-contraction coupling
-
Class IV antidysrhythmics (2)
- Verapamil and Diltiazem
- Ca channel blocker
- Acts primarily on nodal tissue (as AP highly dependent on L and T type Ca channels
- Slow conduction rate, prolong refractory period
- Can compromise excitation-contraction coupling
-
Digoxin
- Cardiac glycoside
- Inhibits Na/K ATPase -> reduces activity of NCX -> Increased intracellular calcium -> Increased contractile force of heart
- Used in heart failure/dysrhythmias
-
Digitoxin
- Cardiac glycoside
- Inhibits Na/K ATPase -> reduces activity of NCX
- -> Increased intracellular calcium -> Increased contractile force
- of heart
- Used in heart failure/dysrhythmias
-
Ouabain
- Cardiac glycoside
- Inhibits Na/K ATPase -> reduces activity of NCX
- -> Increased intracellular calcium -> Increased contractile force
- of heart
- Too powerful to be used clinically; used experimentally
-
3 cardiac glycosides
mechanism
- Digoxin
- Digitoxin
- Ouabain
- Inhibits Na/K ATPase -> reduces activity of NCX -> Increased intracellular calcium -> Increased contractile force of heart
-
Dobutamine
used for?
disadvantages?
- Beta-1 agonist
- Produces positive inotropic effect
- Used IV for shock/to improve CO after open heart surgery/in heart failure in the absence of hypertension
- BUT increases cardiac O2 demand and HR -> may precipitate or reveal dysrhythmias
- May precipitate/potentiate hypertension
-
Bisoprolol
- Beta blocker
- Reduces damage due to chronic adrenergic stimulation eg downregulation and desensitisation of recepors, apoptosis
- Potential danger of over-inhibition
- Used for cardiac failure and hypertension
- Decreases plasma renin, increases plasma NA -> CNS side effects inc insomnia, depression
-
Carvediol
- Beta blocker
- Reduces damage due to chronic adrenergic stimulation eg downregulation and desensitisation of recepors, apoptosis
- Potential danger of over-inhibition
-
Milrinone
- Phosphodiesterase type III inhibitor (cGMP inhibited)
- Inodilator to increase cAMP and mimic beta stimulation
- Used for heart failure
- Can lead to dysrhythmias
- Also vasodilation -> reduced after load on heart (therapeutically beneficial)
-
Dypiridamole
- Phosphodiesterase type V inhibitor (cGMP specific)
- Inodilator to increase cAMP (cGMP?) and mimic beta stimulation
- Used for heart failure
- Can lead to dysrhythmias
- Also vasodilation -> reduced after load on heart (therapeutically beneficial)
-
Sildenafil
- Phosphodiesterase type V inhibitor (cGMP specific)
- AKA Viagra
- Inodilator to increase cAMP (cGMP?) and mimic beta stimulation
- Used for erectile dysfunction (could also be used for heart failure)
-
Methyxamines
- Caffeine and Theophylline
- Non-selective phosphodiesterase inhibitors
- Adenosine A1 and A2 antagonists
- Cause release of Ca from intracellular stores
- Positive inotropic and chronotropic effects -> can predispose dysrhythmias
-
Caffeine
- Non-selective phosphodiesterase inhibitor
- Adenosine A1 antagonist
- Cause release of Ca from intracellular stores
- Positive inotropic and chronotropic effects -> can predispose dysrhythmias
-
Theophylline
- Non-selective phosphodiesterase inhibitor
- Adenosine A2 antagonist
- Cause release of Ca from intracellular stotres
- Positive inotropic and chronotropic effects -> can predispose dysrhythmias
-
Pimobendan
- Calcium sensitiser - increases Ca binding efficiency to troponin
- Peripheral vasodilation by inhibiting Phosphodiesterase type III
- Inodilator used in canine dilated cardiomyopathy/mitral valve regurgitation
-
Livosimendan
- Calcium sensitiser - increases Ca binding efficiency to troponin
- Peripheral vasodilation by inhibiting Phosphodiesterase type III
-
Bosentan
- Non-specific endothelin antagonist
- (ETA and ETB both cause vascular smooth muscle contraction)
- Used for pulmonary arterial hypertension
-
Streptokinase
- Clot lysis
- Causes generation of plamin by binding to plasminogen activator
- -> degradation of fibrin and clotting factors II, V, VII
- 47kDa protein formed by haemolytic streptococci
-
Anistreplase
- Clot lysis
- Comination of plasminogen (substrate) and anisoylated streptokinase
- Anisoyl group is removed in the blood to activate it (half life ~2 hours)
- Long lasting -> 4-6 hours
-
Alteplase
- Clot lysis
- Recombinant human tissue plasminogen activator
- Localised action: greater activity on plasminogen bound to fibrin in clots
- Single chain
-
Duteplase
- Clot lysis
- Recombinant human tissue plasminogen activator
- Localised action: greater activity on plasminogen bound to fibrin in clots
- Double chain
-
Aspirin
NSAID, used with clot lysing agents to prevent further thrombosis
-
Clopidogrel
- Anti-clot
- Inhibits platelet aggregation by inhibiting ADP binding to platelets
-
Eptifibatide
- Anti-clotting agent
- Inhibits glycoprotein IIb/IIIa receptor, needed for fibrinogen bridging between platelets and between platelets and foreign surfaces
- Cyclic heptapeptide
-
Tirofiban
- Anti-clotting agent
- Inhibits glycoprotein IIb/IIIa receptor, needed for fibrinogen bridging between platelets and between platelets and foreign surfaces
- Non-peptide
- Can be used for prevention of myocardial infarction in patients with unstable angina/those who have recently suffered certain types of myocardial infarction
-
Abciximab
2 mechanisms
- Anti-clotting agent
- Monoclonal antibody against glycoprotein IIb/IIIa receptor (needed for fibrinogen bridging between platelets and between platelets and foreign surfaces)
- Also binds to vitronectin receptors on endothelial cells, vascular smooth muscle cells and platelets (involved in cell adhesion and homeostasis)
- Used with coronary angioplasty for coronary artery thrombosis
-
Heparin
mech
use
- Anticoagulant
- Activates antithrombin III via a conformational change
- -> Inactivation of thrombin and proteases inc factor Xa
- Produced by basophils and mast cells
- Used for unstable angina, after MI, DVT, to prevent clots during and after surgery
- Has to be given via injection
-
Warfarin
- Anticoagulant
- Inhibits synthesis of clotting factors II, VII, IX, X and regulatory protein factors protein C, protein S, protein Z
- Prophylactic to protect against thrombosis (eg with increased tendency/history/prosthetic heart valves)
- Given orally
- Interacts with food/drink/other drugs
- Also used as a rodenticide
-
Dabigatran
- Anticoagulant
- Thrombin inhibitor
- Reduces risk of atrial fibrillation/stroke by 40% compared with warfarin
-
Aminocaproic acid
Competitvely inhibits plasminogen activation to prevent sever bleeding
-
Tranexamic acid
- Competitvely inhibits plasminogen activation to prevent sever bleeding
- Analogue of aminocaproic acid
-
Furosemide
- Loop diuretic
- Blocks NKCC in Thick AL
- Also venodilation -> reduced atrial filling pressure
- Potentiates action at nephron by increasing renal blood flow without a change in GFR (reducing the fraction of the blood flow filtered at the glomerulus)
-
Bumetanide
- Loop diuretic
- Blocks NKCC in Thick AL
-
Probenecid
- Competes for uric acid carrier in proximal tubule
- -> Inhibits uric acid reabsorption
- Used to treat gout (depositon of sodium urate crystals in synovial joints)
-
Hydrochlorothiazide
- Thiazide diuretic
- Block Na/Cl cotransport in early distal tubule/cortical segment of Thick AL
- Some carbonic anhydrase inhibition
- Thiazide diureticBlock Na/Cl cotransport in early distal tubule/cortical segment of Thick AL
-
Bendroflumethiazide
- Thiazide diuretic
- Block Na/Cl cotransport in early distal tubule/cortical segment of Thick AL
- Some carbonic anhydrase inhibition
- Vasodilatory effects: initially relieve hypertension through diuretic effects, then through direct effects on blood vessels
-
Diazoxide
- Vasodilator, non-diuretic thiazide
- Opens K sensitive ATP channels
- Used in hypertensive emergencies
-
Amiloride
- Potassium sparing diuretic
- Blocks apical Na channels in late distal tubule
-
Triamterene
- Potassium sparing diuretic
- Blocks apical Na channels in late distal tubule
-
Spironolactone
- Potassium sparing diuretic
- Aldosterone antagonist in late distal tubule
- Reduced upregulation of Na channels and Na/K ATPase
-
Canrenone
- Metabolite of spironolactone - responsible for some of its effects?
- (K sparing diuretic via aldosterone antagonist)
-
Potassium canrenoate
K sparing diuretic
-
Acetazolamide
- Carbonic anhydride inhibitor
- Not potent enough for appreciable diuresis - would need >99% of channels blocked
- Used for glacoma: supresses HCO3- secretion, inhibiting aqueous humour production
- Can be used for altitude sickness due to changes in blood acid/base balance that increase the respiratory drive
-
Mannitol
- Polysaccharide osmotic diuretic
- Reduces intracranial and intraocular pressure - useful in cerebral oedema due to head injuries
-
Captopril
ACE inhibitor, for hypertension and heart failure
-
Enalapril
- ACE inhibitor, for hypertension and heart failure
- Needs to be converted to enalaprilat in liver
-
Enalaprilat
- ACE inhibitor, for hypertension and heart failure
- Converted from enalapril in liver
-
Saralasin
- Angiotensin II partial agonist
- Peptide - not suitable for oral administration
-
Losartan
- Angiotensin II antagonist
- Non-peptide
- an ARB: angiotensin receptor blocker, acting on AT1 receptors
-
Aliskiren
Renin inhibitor
-
Atenolol
- Beta 1 blocker
- Hypertension
-
Doxazosin
- alpha-1 antagonist
- used for hypertension: dilates resistance and capacitance vessels
- Lack of tachycardia (lack of block of alpha-1 receptors?)
- In CNS, decrease SNS by modulating baroceptor reflex mechanisms
-
Prazosin
- alpha-1 antagonist
- used for hypertension, but more usually a veterinary sedative
- reflex fall in BP on first dose -> fainting
-
Phentolamine
- non selective alpha-antagonist
- used for hypertension
- vasodilatation, reflex tachycardia
- increased SNS activity -> increased renin release
-
Nifedipine
- L type Ca channel antagonist
- Reduce hypertension - cardiovascular and mild diuretic effect
- Usually combined with a beta blocker to combat reflex tachycardia
- May inhibit Angiotensin II induced aldosterone release
- May antagonise baroceptor responses - unimportant long term
-
Minoxidil
- K+ channel opener (ATP sensitive channels)
- Used for hypertension (and severe refractory forms)
- Causes hyperpolarisation and relaxation of vascular smooth muscle
- Used with a beta blocker (to stop reflex tachycardia) and a diuretic (to increase blood volume)
-
Nicorandil
- K+ channel opener (ATP sensitive channels)
- Used for hypertension, sometimes angina
- Causes hyperpolarisation and relaxation of vascular smooth muscle
-
Clonidine
- Decreases BP when injected into ventrolateral medulla
- Works on either alpha-2 receptors, or imidazoline I2 receptors
- Antihypertensive
-
Moxonidine
- Centrally acting antihypertensive
- Imidazoline - acts on I-1 receptors in ventrolateral medulla
- Fewer side effects than alpha-2 agonists
-
Guanfacine
- alpha-2 agonist (more specific than clonidine)
- lower antihypertensive efficacy - alpha-2 receptors less important than I-1?
-
Guanethidine
- Sympatholytic antihypertensive
- Acts on synthesis and processing of transmitter
- Can cause postural hypertension
-
Reserpine
- Sympatholytic antihypertensive
- Acts on synthesis and processing of transmitter
- Can cause severe depression
-
Hexamethonium
- Antihypertensive ganglion blocker
- IV, rapid onset
- Blocks all ganglionic transmission - has been superceded
-
Trimetaphan
- Antihypertensive ganglion blocker
- IV, rapid onset
- Blocks all ganglionic transmission - has been superceded
-
Sodium Nitroprusside
- Antihypertensive
- Metabolised -> NO
- In solution, hydrolyses -> cyanide
- Used IV in hypertensive emergencies
-
Hydralazine
- Antihypertensive
- Arteriolar vasodilator
- Mechanism unknown
- Cheap - used quite a lot in 3rd world
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