L21 and L22 Regulation of Arterial Blood Pressure

What is the primary role of the nervous system in short-term blood pressure regulation?

Altering fluid balance to adjust blood volume
Activating the renin-angiotensin-aldosterone system (RAAS)
Modulating the heart rate and contractility through reflexes (correct)
Regulating kidney function to maintain long-term blood pressure

Which of the following is NOT a component of the short-term nervous system regulation of blood pressure?

Abdominal compression reflex
Renin-angiotensin-aldosterone system (RAAS) (correct)
Arterial chemoreceptor reflex
Arterial baroreceptor reflex

How do baroreceptors respond to an increase in arterial blood pressure?

They increase their firing rate, stimulating the cardiac acceleration center to increase heart rate and contractility
They decrease their firing rate, inhibiting the cardiac acceleration center and decreasing sympathetic tone
They decrease their firing rate, inhibiting the cardiac inhibitory center and decreasing vagal tone
They increase their firing rate, stimulating the cardiac inhibitory center to decrease heart rate (correct)

What is the primary function of the renin-angiotensin-aldosterone system (RAAS) in blood pressure regulation?

To regulate fluid balance and vascular tone over the long-term (C) Signup and view all the answers

What is the role of the kidney in the long-term regulation of arterial blood pressure?

The kidney releases renin to activate the RAAS system and regulate fluid balance (A) Signup and view all the answers

Which of the following is NOT a type of hypertension?

Resistant hypertension (A) Signup and view all the answers

What is the primary difference between primary (essential) and secondary hypertension?

Primary hypertension is more common and occurs without an underlying medical condition (A) Signup and view all the answers

Which of the following is a key mechanism by which the kidney regulates long-term blood pressure?

Modulating fluid balance and vascular tone through the renin-angiotensin-aldosterone system (C) Signup and view all the answers

Which of the following is not one of the long-term regulatory systems for arterial blood pressure?

Thyroid Hormone (B) Signup and view all the answers

What is the primary effect of angiotensin II on the body?

Stimulation of aldosterone secretion (D) Signup and view all the answers

How does Antidiuretic Hormone (ADH) help regulate long-term arterial blood pressure?

ADH increases water reabsorption, increasing blood volume (A) Signup and view all the answers

What is the primary stimulus for the release of Atrial Natriuretic Peptide (ANP)?

Increased arterial blood pressure (A) Signup and view all the answers

What percentage of hypertension cases are classified as primary (essential or idiopathic) hypertension?

90% (D) Signup and view all the answers

What is the definition of hypertension?

Persistent elevation of both systolic and diastolic blood pressure above 140/90 mmHg (B) Signup and view all the answers

Which of the following is not a cause of Antidiuretic Hormone (ADH) release?

Increase in body temperature (B) Signup and view all the answers

How does Atrial Natriuretic Peptide (ANP) help regulate long-term arterial blood pressure?

ANP increases water and sodium excretion in the kidneys, decreasing blood pressure (B) Signup and view all the answers

What is the first mechanism mentioned for the intermediate-term regulation of arterial blood pressure?

Renin-angiotensin vasoconstriction mechanism (B) Signup and view all the answers

Which enzyme converts angiotensin I into angiotensin II?

Angiotensin-converting enzyme (ACE) (C) Signup and view all the answers

What is the effect of angiotensin II on arterial blood pressure?

Vasoconstriction and increased blood pressure (B) Signup and view all the answers

What is the second mechanism mentioned for the intermediate-term regulation of arterial blood pressure?

Capillary fluid shift mechanism (B) Signup and view all the answers

What is the effect of an increase in blood volume on arterial blood pressure according to the capillary fluid shift mechanism?

Increase in capillary hydrostatic pressure, leading to increased filtration to tissue spaces and decreased blood volume, ultimately decreasing arterial blood pressure (C) Signup and view all the answers

What is the third mechanism mentioned for the intermediate-term regulation of arterial blood pressure?

Stress relaxation mechanism (D) Signup and view all the answers

Which of the following is NOT mentioned as a long-term regulation mechanism for arterial blood pressure?

Capillary fluid shift (D) Signup and view all the answers

What is the effect of an increase in blood pressure according to the stress relaxation mechanism?

Increased stretch of the arteries, leading to relaxation of the arteries and a decrease in blood pressure (A) Signup and view all the answers

What is the main reason for the lack of increase in baroreceptor discharge in chronic hypertension?

The baroreceptors have become desensitized to the elevated arterial blood pressure (C) Signup and view all the answers

Where are the arterial chemoreceptors located?

In the carotid bodies and aortic bodies (C) Signup and view all the answers

What is the effect of a decrease in arterial blood pressure below 60 mmHg on the peripheral chemoreceptors?

The peripheral chemoreceptors are stimulated, leading to an increase in sympathetic activity and catecholamine release (D) Signup and view all the answers

What is the purpose of the CNS ischemic response when arterial blood pressure drops below 60 mmHg?

To increase blood pressure and maintain cerebral blood flow (B) Signup and view all the answers

How does the abdominal compression reflex help regulate arterial blood pressure?

It increases venous return to the heart, leading to an increase in blood pressure (B) Signup and view all the answers

What is the primary difference between the short-term and intermediate-term regulation of arterial blood pressure?

The short-term mechanisms act within seconds, while the intermediate-term mechanisms act within minutes and last for days (A) Signup and view all the answers

What is the primary function of the carotid and aortic bodies in the regulation of arterial blood pressure?

To detect changes in arterial blood pressure and adjust sympathetic and parasympathetic tone accordingly (C) Signup and view all the answers

What is the main purpose of the intermediate-term regulation of arterial blood pressure?

To compensate for the fatigue and decreased effectiveness of the short-term mechanisms (A) Signup and view all the answers

In a patient with stenosis of both renal arteries, leading to severely decreased blood flow to the renal arterioles, what effect would this have on blood pressure?

Increase blood pressure (B) Signup and view all the answers

If a medication inhibits an enzymatic process that occurs in the lungs, which step of the RAAS pathway is most directly inhibited?

Conversion of angiotensin I to angiotensin II (D) Signup and view all the answers

Which of the following is primarily responsible for short-term regulation of blood pressure?

Nervous system (B) Signup and view all the answers

Which of the following is the primary mechanism for long-term regulation of blood pressure?

Renal mechanisms (C) Signup and view all the answers

Which of the following is a common secondary cause of hypertension?

All of the above (D) Signup and view all the answers

What is the primary function of aldosterone in the regulation of blood pressure?

Increase sodium and water reabsorption in the kidneys (B) Signup and view all the answers

Which of the following conditions is characterized by an increased red blood cell mass, potentially leading to increased blood viscosity and hypertension?

Polycythemia vera (A) Signup and view all the answers

What percentage of all hypertension cases are classified as secondary hypertension?

10% (A) Signup and view all the answers