Diuretics Flashcards
T/F: Water will follow Na during resorption/secretion.
True
What happens to water if you block Na resorption into the blood?
More water will leave in the urine
How will the resorption of less Na effect blood pressure?
Less Na resorbed = less H2O resorbed.
If less H2O in the blood -> blood volume decreases
Decrease in blood volume = decrease in blood pressure
T/F: Most of the filtered plasma gets excreted as urine.
False
Out of 180 liters only 1.5 is excreted per day
Where do carbonic anhydrase inhibitors act?
Proximal convoluted tubule
What is the goal of carbonic anhydrase?
To facilitate the shuttling of Na+ from the lumen back into the blood.
(Bicarbonate comes with it as well)
What is the overall effect of CA inhibitors?
Inhibits Na+ resorption -> enhances fluid loss -> lowers blood volume/pressure
Where do osmotic diuretics work?
Proximal convoluted tubule and proximal straight tubule
____________ diuretics work by increasing the osmolarity of blood and renal filtrate.
Osmotic
Mannitol is an example of a ___________ diuretic. It is not well resorbed back into the blood, and thus water will stick with it and not be resorbed.
Osmotic
Where do loop diuretics act?
Thick ascending limb
T/F: Loop diuretics are most effective in patients with impaired kidney function.
True
How do loop diuretics work?
Block a transporter that brings Na+, Cl-, and K+ in from the lumen.
What are some possible side effects from loop diuretics?
Mg and Ca imbalances
________________ are sulfonamide derivatives, and therefor could cause allergic reactions.
Loop diuretics
Where do thiazides diuretics work?
Distal convoluted tubule
_________ diuretics inhibit a Na+ Cl- symporter from the lumen to tubular cells.
Thiazide
Which two types of diuretics can cause K+ loss and lead to ion imbalances?
Thiazides and loop diuretics
Where do K+ sparing diuretics work?
Cortical collecting tubule
In what two ways do K+ sparing diuretics work?
- Na+ channel from lumen into cell
2. Aldosterone receptor antagonist
______________ are used as adjunctive therapy, together with other drugs, in the treatment of hypertension and management of CHF.
K+ sparing diuretics
T/F: Diuretics make you pee more.
True
What are the two blood pressure regulatory system?
Short term = sympathetic nervous system
Long term = renal system
Describe the baroreflex regulation of blood pressure.
Baroreceptors send BP info to medulla -> symp nerves adjust to regulate vasoconstriction, heart beat, cardiac output
Where are baroreceptors found in the kidney?
JG cells
What is released from the juxtaglomerular apparatus when blood pressure decreases?
Renin
What is the role of renin in regulating BP?
Renin turns angiotensinogen into angiotensin I
Angiotensin I is then converted into angiotensin II by ACE
Where is angiotensinogen secreted?
Liver
Where is angiotensin I converted to angiotensin II?
In the lung capillaries by ACE
What are the effects of angiotensin II?
Direct and indirect vasoconstriction, sodium resorption and water retention
Long term: can produce structural remodeling
INCREASE BP
Which angiotensin II receptor is important for pharm intervention?
AT1 receptor (GPCR)
T/F: Angiotensin II stimulates aldosterone release.
True
What are the four classes of drugs used to treat hypertension?
- Diuretics - reduce blood volume
- Sympathoplegic - reduce vascular resistance and CO
- Direct vasodilators - relax smooth muscle
- Block angiotensin II - reduce vascular resistance and blood volume
___________ diuretics are favored for patients with mild to moderate hypertension and normal renal and cardiac function.
Thiazide
Which type of diuretics are used with more severe hypertension?
Loop
What is the most common side effect of diuretics for hypertension?
K+ depletion
What are the three ways sympathoplegic agents work?
- Act on CNS
- Reduce epinephrine release
- Block adrenoreceptors
Use diuretics in conjunction to prevent Na retention
Sympathoplegic agents that act on the CNS activate _____ receptors, reducing cardiac output.
alpha2
Sympathoplegic drugs that selectively block adrenoreceptors are aiming to block beta1 receptors having what effect?
Diminish CO and renin production
What are the four methods that direct vasodilators use to treat hypertension?
- NO drugs
- Reduce Ca+ influx
- Hyperpolarize (activate K+ channel)
- Activate dopamine
What is one of the negative aspects of direct vasodilators?
The body senses the changes and tries to compensate
Often have to take more drugs to oppose compensation
Which dopamine receptor do some direct vasodilators effect?
D1
T/F: ACE inhibitors would inhibit angiotensin I production.
False
Angiotensin II
How do ACE inhibitors promote vasodilation?
ACE normally degrades bradykinin which is a vasodilator
Inhibit ACE -> more bradykinin, more vasodilation
What class of drugs end in -pril?
ACE inhibitors
T/F: Lisinopril is a prodrug.
False
T/F: ACE inhibitors decrease cardiac output and heart rate.
False
Decrease peripheral vascular resistance
No effect on heart
Useful if kidney is compromised
What class of drugs end in -sartan?
Antagonists for angiotensin receptor
Angiotensin antagonists bind to _____ receptors.
AT1
T/F: Angiotensin antagonists affect bradykinin metabolism.
False
ACE inhibitors do
