Endogenous Hormones - Cardiac Pharm Flashcards
What does ANP stand for?
Atrial Natriuretic Peptide
ANP is a natriuretic peptide released from atrial myocytes.
What triggers the release of ANP?
Stretch of atrial myocytes
What are the effects of ANP?
Promotes vasodilation, natriuresis, and diuresis; suppresses RAAS
What role does ANP play in the body?
Regulates blood pressure/volume and serves as a marker in heart failure
What may occur with excess release of ANP?
Hypotension and electrolyte imbalances
What does BNP stand for?
B-type Natriuretic Peptide
BNP is a natriuretic peptide secreted by ventricular myocytes.
What triggers the secretion of BNP?
Increased wall stress in the ventricles
What are the effects of BNP?
Similar to ANP; aids in volume regulation
What is the significance of elevated BNP levels?
Indicates cardiac stress and aids in diagnosing heart failure
What should be monitored in patients with elevated BNP?
Signs of heart failure and hypotension
What are ANP and BNP considered?
Cardiac Natriuretic Peptides
What is Endothelin?
A peptide vasoconstrictor produced by endothelial cells
very potent
What is the primary function of Endothelin?
Stimulates smooth muscle contraction
What role does Endothelin play in the body?
Contributes to vascular tone; implicated in hypertension and pulmonary arterial hypertension
What can excess Endothelin lead to?
Worsening of ischemia and hypertension; careful monitoring of blood pressure is warranted
What is Nitric Oxide (NO)?
A gaseous signaling molecule
How does Nitric Oxide (NO) affect smooth muscle cells?
Diffuses into smooth muscle cells increasing cGMP levels, resulting in vasodilation
What is the therapeutic role of Nitric Oxide (NO)?
Regulates vascular tone and blood flow; therapeutic vasodilator in pulmonary hypertension
What are potential issues with overproduction of Nitric Oxide (NO)?
May lead to hypotension and headache; monitor hemodynamic status
What are the endothelial factors? (2)
endothelin and nitric oxide
What is the function of Renin in the RAAS?
Proteolytic enzyme hormone that cleaves angiotensinogen into angiotensin I
Secreted by the juxtaglomerular cells; initiates RAAS cascade for blood pressure and fluid balance regulation. Overactivity can contribute to hypertension; monitor blood pressure and renal function.
What is Angiotensinogen?
Precursor protein hormone produced by the liver that serves as substrate for renin to generate angiotensin I
Integral to RAAS; its conversion initiates the cascade. Elevated levels can predispose to hypertension indirectly; assessed as part of RAAS evaluation.
What is Angiotensin I?
Inactive peptide precursor formed from angiotensinogen by renin
Converted to angiotensin II by ACE; serves as a marker of RAAS activation but has no direct activity.
What role does Angiotensin II play in the body?
Active vasoconstrictor peptide that binds to AT1 receptors to cause vasoconstriction and stimulates aldosterone release
Key mediator in hypertension and heart failure; excess may lead to severe hypertension, vascular damage, and cardiac strain.
What is the function of Angiotensin Converting Enzyme (ACE)?
Enzyme that converts angiotensin I to angiotensin II and degrades bradykinin
Central in RAAS regulation; target for ACE inhibitors in hypertension and heart failure. Inhibition may cause cough or angioedema due to bradykinin accumulation.
What is Aldosterone?
Mineralocorticoid hormone that acts on renal distal tubules to increase sodium reabsorption and potassium excretion
Regulates blood volume and pressure; excess contributes to edema and hypertension. High levels can cause fluid retention, edema, and hypokalemia.
True or False: Angiotensin I has direct activity in blood pressure regulation.
False
Angiotensin I is inactive until converted to angiotensin II.
Fill in the blank: Angiotensin II is a key mediator in _______ and heart failure.
hypertension
It is also used as a vasopressor in septic shock.
What can excessive levels of Angiotensin II lead to?
Severe hypertension, vascular damage, and cardiac strain
Important to monitor blood pressure and electrolytes.
What is the consequence of inhibiting ACE?
May cause cough or angioedema due to bradykinin accumulation
It is important to monitor for respiratory symptoms.
What physiological effect does Aldosterone have?
Increases sodium reabsorption and potassium excretion
This regulation is crucial for maintaining blood volume and pressure.
What is the function of Anti-diuretic Hormone (ADH)?
Binds to renal V2 receptors to promote water reabsorption and V1 receptors to induce vasoconstriction
Maintains water balance; used therapeutically in diabetes insipidus and vasodilatory shock scenarios
What can excess ADH lead to?
Water intoxication and hyponatremia
Monitor fluid intake, output, and serum sodium levels
What is Bradykinin?
Peptide mediator that induces vasodilation, increases vascular permeability, and stimulates pain receptors
Involved in fibrinolysis
What roles does Bradykinin play in the body?
Contributes to inflammation and pain; implicated in ACE inhibitor–induced cough and angioedema
Overactivity may lead to hypotension, cough, and angioedema
True or False: Bradykinin is involved in fibrinolysis.
True
What should be monitored in cases of excess ADH?
Fluid intake, output, and serum sodium levels
What are the effects of Bradykinin overactivity?
Hypotension, cough, and angioedema
What type of drug is ADH (vasopressin)?
Peptide hormone
