Pharmacology-Antihypertensives Flashcards
Organs responsible for regulating bp
Liver
Lungs
Kidneys
Adrenal gland
Heart
How to calculate Blood Pressure (Arterial BP) =
Cardiac Output x TPR
Systolic BP vs. Diastolic BP
Systolic = Heart contracting
Diastolic = Heart relaxing
Normal bp = 120/80
Antihypertensives
A: Ace Inhibitor, Angiotensin receptor blockers, Alpha-1 receptor Blockers
B: Beta-blockers (selective & non-selective)
C: CCB
D: Diuretics
E: Endothelin receptor antagonists
RAAS system
The liver produces angiotensinogen.
When there is a decrease in BP, the kidneys produce renin.
Renin is responsible for converting angiotensinogen to angiotensin I
Angiotensinogen circulates the body, contacting a membrane-bound enzyme (ACE) mainly residing in lung tissue.
Angiotensin I gets converted into angiotensin II. Angiotensin II is an important regulator of blood pressure.
Angiotensin II increases BP via the following mechanisms:
1. Increasing sympathetic activity
2. Vasoconstriction
3. Increase in aldosterone
How to remember ACE inhibitor medication
End in (-prils)
ACE inhibitor (CAPTOPRIL)
C -cough
A -angioedema
P-pregnancy problems
T- taste changes
O - other (rash, fatigue)
P - proteinuria
R - renal insufficiency
I - increased potassium
L - Low BP
Angiotensin receptor blockers
How can you remember Angiotensin receptor blockers medication
end in (-sartans)
Where can you find alpha-1 receptor
SMC that surround vessels of epithelial cells
What do alpha-1 receptors react to?
Adrenaline/Noradrenaline produced by adrenonergic neurons
What happens when noradrenaline/adrenaline binds to alpha 1 receptor?
Stimulates contraction of the smooth muscle cells that surround vells.
This narrows the lumen and increases BP
Alpha-1 Receptor Blocker
What do beta blocker medications end with
(~olol)
What activity are beta blockers important for?
sympathetic activity
By blocking the beta receptors you are blocking the sympathetic activity
Selective vs Non-selective beta blockers
Selective: work on heart
Non-selective: work on heart and other tissues
What is the name of the receptors found on pacemaker heart cells?
Beta 1 receptors
How can pacemaker cells increase blood pressure?
Adrenergic neurons release adrenaline/noradrenaline that bind to beta-1 receptors of pacemaker cells.
This increases heart rate and therefore blood pressure
Where can you find beta-1 receptors in the circulatory system?
Pacemaker cells
Cardiomyocytes
What is the result of noradrenaline binding to cardiomyocytes
Stimulate the beta-1 receptors of the cardiomyocytes leading to a more powerful contraction .
This increases CO -> Increase BP
Beta blockers
What do calcuim channel blocker medication end in?
(~dipine)
What is the role of calcium in the body
Excitability and muscle contraction
What calcium channels do you find in pacemaker cells?
T-Type calcium channels
What calcium channels do you find on smooth muscle cells
L-type calcium channels
Calcium Channel blocker
Contraindications include: congestive heart failure, heart block, hypotension, ventricular tachycardia
What organ to diuretics work on?
Kindeys (more specifically the nephrons)
They induce diuresis
Functional unit of kidney?
Nephron
What part of the nephron do loop diuretics work on
Ascending part in the loop of Henle
What part of nephron do thiazide work on?
Distal part of the nephron
What part of nephron do K+ sparing diuretics work on?
Distal part of nephron
How do all diuretics essentially work?
All inhibit sodium from going into the bloodstream, meaning you have more sodium being excreted. Meaning a decrease in BP
Diuretics
Side effects of taking diuretics
Endothelin receptor antagonist
Work on blood vessel of SMC containing Endothelin-1 receptor.
When endothelin binds to it, it will cause contraction and narrowing of blood vessel
ACEi should never be prescribed with
Angiotensin receptor blocker
