Human Aspects of Cardiovascular and Renal Pharmacology Deck Flashcards
Atenolol
β1 adrenoreceptor antagonist that has antihypertensive effects. Unclear exact mode of action. Also used to treat angina.
Bisoprolol
β1 adrenoreceptor antagonist that has antihypertensive effects. Unclear exact mode of action. Also used to treat angina.
Pindolol
Partial β1 adrenoreceptor agonist. Due to mild nature has little effect on cardiac output.
Prazosin
α1 adrenoreceptor antagonists. Prazosin is the archetypal example, but Doxazosin is the most commonly used. Lack of presynaptic α2 receptor block means that there is no reflex tachycardia.
Doxazosin
α1 adrenoreceptor antagonist. Doxazosin is the most commonly used and dilates resistance and capacitance vessels. Lack of presynaptic α2 receptor block means that there is no reflex tachycardia.
Phentolamine
Non-selective α adrenoreceptor antagonist. Gives vasodilation accompanied by reflex tachycardia.
Labetolol
α1, β1 and β2 antagonist (more so β than α). Antihypertensive.
Amlodipine
L-Type Ca2+ channel antagonist. Most commonly prescribed dihydropyridine. Antihypertensive effect mainly due to reduction of smooth muscle contraction.
Minoxidil
KCO used to treat hypertension. Acts on ATP-sensitive K+ channels, opening them, causing hyperpolarisation and relaxation of vascular smooth muscle. Can be used in severe refractory hypertension in combination with a β blocker and diuretic. It also causes some hirsutisms so has some use as a topical hair loss treatment.
Clonidine
Centrally acting α2 agonists. Guanfacine is more potent as α2 agonist but has lower efficacy than clonidine as an antihypertensive. Their effect originally thought to be due to decreasing NA release by acting on CNS presynaptic receptors but effect may be through I1 receptor. Clonidine withdrawal has marked effects.
Guanfacine
Centrally acting α2 agonists. Guanfacine is more potent as α2 agonist but has lower efficacy than clonidine as an antihypertensive. Their effect originally thought to be due to decreasing NA release by acting on CNS presynaptic receptors but effect may be through I1 receptor.
Moxonidine
Imidazoline drug that mimics the effects of clonidine and guanfacine. Centrally acting antihypertenive with fewer side effects than α2 agonists.
α-Methyldopa
Converted into α-methylnoradrenaline. False transmitter of NA system. It is less potent at α1 adrenoreceptors but more potent at α2 adrenoreceptors than NA. Centrally acting anti-hypertensive agent.
Hexamethonium
Antihypertensive ganglionic blocker. First used as an antihypertensive in the 1950s. Since they block all ganglionic transmission they were soon superceded by more specific agents. They are only used in certain surgical procedures to control local blood flow.
Trimetaphan
Antihypertensive ganglionic blocker. First used as an antihypertensive in the 1950s. Since they block all ganglionic transmission they were soon superceded by more specific agents. They are only used in certain surgical procedures to control local blood flow.
Sodium Nitroprusside
Directly acting vasodilator, metabolised to NO. However in solution it also hydrolyses to give cyanide, so is used intravenously in hypertensive emergencies.
Hydralazine
Arteriolar vasodilator with unknown mechanism.
Simvastatin
2nd generation statin, most widely prescribed for at risk individuals. It acts by inhibiting HMG-CoA reductase, decreasing cholesterol synthesis so liver has to take up more LDL from the blood. This decreases predisposition to atheroma formation.
Clofibrate
Fibric acid derivative which lowers VLDL and (to a lesser extent) LDL. It stimulates lipoprotein lipase, releasing triglycerides from VLDL and chylomicrons. The lipid can then be taken and stored in fat or metabolised in skeletal muscle.
Rosiglitazone
PPARγ agonist. Induces LXR transcription, leading to indirect induction of ABCA1, which controls the rate limiting step in HDL synthesis. Reported to reduce atherosclerosis in both experimental models and clinical trials.
Colestyramine
Anion exchange resin. It prevents reuptake of bile acids from the intestine by sequestering them in the gut lumen, so causes an increase in cholesterol metabolism to synthesise bile acids in the liver. Unpleasant side effect of chronic diarrhoea.
Nicotinic Acid
Inhibitor of liver triglyceride production and VLDL secretion when used in large doses. Increases levels of t-PA.
Ezetimibe
Inhibits intestinal absorption of cholesterol by targeting NPC1L1 protein which transports sterol across brush border and is also present in the liver where it helps the reabsorption of cholesterol from bile. It circulates enterohepatically so is repeatedly re-delivered to the intestine, can be used in combination with a statin or alone.
Glyceryl Trinitrate
“Nitrovasodilator”. Organic nitroderivatives. Both glyceryl trinitrate and isosorbide dinitrate are commonly used to treat angina, the former especially in acute attacks. Glyceryl trinitrate is poorly absorbed from the stomach and so is taken sub-lingually (absorbed directly into systemic circulation). Causes vasodilation by being converted to NO in vascular smooth muscle cells. The main way that nitrovasodilators work in angina is by causing venous dilation, reducing RAP and decreasing the work done by the heart. They also seems to cause vasodilation in collateral vessels of ischaemic areas preferentially. May cause headache.