Pharmacology and CVD Flashcards
Define Hypertension
a condition where arterial BP is elevated above normal levels
in what unit is BP measured?
mmHg
what are the classification levels of hypertension?
Normal= <120/80 Prehypertensive= 120-139/80-89 Stage 1= 140-159/90-99 Stage 2=160/100+ Stage 3= 180/110+
what are the two types of hypertension?
primary hypertension- hypertension with no know cause
secondary hypertension- hypertension with a secondary cause
how prevalent is secondary hypertension?
affects 10-15% of all cases.
what are the causes of secondary hypertension?
Renal artery stenosis Chronic renal disease Hyperaldosteronism Cushing’s disease Hyperthyroidism Phaeochromocytoma Pre-eclampsia Aortic coarctation Sleep apnoea Antidepressant drugs
What are the risk factors of primary hypertension?
you should know this any way age race familial history gender obesity alcohol/tobacco use sedentary life style salt etc etc etc... (vitamin D)
what are the 5 classes of hypertensive drugs?
Diuretics Sympatholytics Directly-acting vasodilators Calcium antagonists Drugs acting on Renin-angiotensin system
What areas are tageted by antihypertensive drugs?
Sympathetic NS Heart (Cardiac output) Kidney (Blood volume) Arterioles (Peripheral resistance) Endothelial cells (NO) Renin-angiotensin system (AII) CNS (Medulla oblongata)-CNS actions to reduce sympathetic tone
what are the 3 types of diuretics?
thiazides
loop diuretics
potassium-sparing
give an example of a thiazide and briefly describe how it works
hydrochlorothiazide
inhibits Na+/CL- co-transporter on luminal membrane of early distal convoluted tubule
activation of ATP-regulated K+ channels in resistance vessels
what are the 3 types of sympatholytics?
centrally acting ganglion blockers NA store depletion adrenergic neurone blockers Alpha-blockers Beta-blockers
give an example of an alpha blocker and briefly describe how it works
prazosin
Competitively antagonises alpha-1 adrenoceptors on arterioles to cause vasodilation in resistance vessels
give an example of an beta blocker and briefly describe how it works
pindolol (partial antagonist)
binds at cardiac beta-1 adrenoceptors to reduce Cadiac output
other examples of beta blockers are:
Propranolol (non-selective)
Atenolol (beta-1 selective, water soluble)
Labetalol (alpha and beta blocker)
give an example of a direclty-acting vasodilatore and briefly describe how it works
Minoxidil
Activates ATP-sensitive K+ channels in arterial resistance vessels
Activation of NO release
Reduction of Ca2+ influx (L- type)
other examples are:
Hydralazine
Sodium nitroprusside
Diazoxide
give an example of a calcium channel blocker and briefly describe how it works
Verapamil
Interfere with inward displacement of Ca2+
Through slow channels of arterial muscle (L-type channels)
give an example of an ACE inhibitor and briefly describe how it works
Captopril (an ACE inhibitor) a drug which acts on the renin-angiotensin system
Angiotensin converting enzyme (ACE) is a carboxypeptidase which cleaves off 2 amino acids at the leucine terminal of Angiotensin 1 (Active site has a Zn atom)
ACE inhibitors have a sulphydryl group which attaches to the Zn atom
Inhibition of Kininase II which breaks down bradykinin
what are the 3 types of drugs which act on the renin-angiotensin system?
ACE inhibitor
AT1 antagonist
Renin inhhibitor
give an example of an AT1 antagonist and briefly describe how it works
Losartan
Antagonist at AT1 receptors
give an example of a renin inhibitor and briefly describe how it works
Aliskiren
Orally active non-peptide inhibitor of Renin
