Lecture 7: Drugs to treat high blood pressure I Flashcards
What is blood pressure
- is generated by beating of the heart, and resistance of the circulatory system
- blood in the circulatory system is under pressure in order distribute through the system
How does blood pressure change during the cardiac cycle
- pressure at the peak of ventricular contraction is called systolic pressure
- minimum pressure during ventricular relaxation is called diastolic pressure
What are the different types of blood pressure?
- less that 120/80 - normal
- 120-139/80-89 - prehypertension
- greater than 140/90 - hypertension
- 140-159/90/99 - stage 1
greater than 160/100 - stage 2
How is high blood pressure a bad thing
- most common cardiovascular disease
- risk of renal failure, coronary disease, heart failure, stroke, dementia
What two main factors regulate blood pressure
cardiac output and peripheral vascular restriction
- harder the heart is working, or higher the resistance of the vasculature, the higher the blood pressure
What are some critical sites where drugs regulate blood pressure?
- heart
- resistance vessels
- RAAS (renin-angiotensin-aldosterone system)
What is method of action of thiazide diuretics
- inhibit NaCl reabsorption in distal convoluted tubule
- mechanism of action is to block Na+/Cl- transporter (NCC)
- reabsorption of sodium is the main driver for water reabsorption in the kidney, which controls water volume as when water is in the tubule, peeing helps reduce blood pressure
What is commonly used thiazide
bendroflumethiazide
What are adrenergic receptors?
g-protein coupled receptors (GPCRs) that are activated by catecholamines like adrenaline, noradrenaline
What adrenergic receptors are in the heart
beta1 receptors are the predominant adrenergic receptor. These are responsible for acceleration of heart rate and pump heart for fight or flight response
