Local control of Blood Flow and Resistance Vasculature Quiz

Play an AI-generated podcast conversation about this lesson

Which molecule is responsible for the relaxation of blood vessels in response to shear stress?

cGMP

Endothelin

cGTP

NO (correct)

What is the main action of cGMP-dependent protein kinase?

Formation of blood clots

Relaxation of blood vessels (correct)

Vasoconstriction

Increase in blood flow

Which substance is released from damaged endothelium and acts as a powerful vasoconstrictor?

Endothelin (correct)

NO

cGMP

cGTP

What happens to vascularity when the metabolism in a tissue is increased for a prolonged period?

Angiogenesis occurs Signup and view all the answers

What is the main mechanism for long-term local blood flow regulation?

Changes in tissue vascularity Signup and view all the answers

What is the term for the increase in vascularity of trained muscles in response to chronic exercise training?

Angiogenesis Signup and view all the answers

What is the main effect of inward eutrophic remodeling?

Decrease in the lumen diameter Signup and view all the answers

What is the main effect of hypertrophic remodeling in larger arteries?

Increase in the cross-sectional area of the vascular wall Signup and view all the answers

Which of the following is NOT a specific need for local control of blood flow in tissues?

Delivery of glucose to tissues Signup and view all the answers

What are the two phases of local blood flow control?

Acute and chronic Signup and view all the answers

What is the main action of endothelin released from damaged endothelium?

Vasoconstriction Signup and view all the answers

What is the main action of NO in vascular smooth muscle cells?

Relaxation of blood vessels Signup and view all the answers

Which blood vessels are involved in the acute control of blood flow?

Arterioles, metarterioles, and precapillary sphincters Signup and view all the answers

What happens to blood flow in a local tissue when the rate of metabolism increases up to 8 times normal?

It increases by fourfold Signup and view all the answers

Which condition can cause an increase in tissue blood flow due to reduced oxygen availability?

High altitudes Signup and view all the answers

What does the second figure in the text show?

The effect of reduced arterial oxygen saturation on blood flow Signup and view all the answers

What is the main characteristic of long-term control of blood flow?

Slow, controlled changes over a period of days, weeks, or months Signup and view all the answers

Which of the following is NOT a condition that can cause an increase in tissue blood flow due to reduced oxygen availability?

Asthma Signup and view all the answers

What is the approximate effect on blood flow when the arterial oxygen saturation decreases to about 25% of normal?

It increases by threefold Signup and view all the answers

How long does the chronic phase of local blood flow control typically last?

Weeks to months Signup and view all the answers

Which of the following substances is NOT suggested as a vasodilator in the vasodilator theory for acute local blood flow regulation?

Oxygen Signup and view all the answers

What is the name of the theory that suggests that blood vessels dilate in the absence of adequate oxygen?

Oxygen Demand Theory Signup and view all the answers

What is the term used to describe the cyclical opening and closing of precapillary sphincters and metarterioles?

Vasomotion Signup and view all the answers

What is the term for the increase in blood flow through a tissue that occurs when the blood supply is blocked and then unblocked?

Reactive hyperemia Signup and view all the answers

What is the primary factor that mediates myogenic regulation of tissue blood flow?

Stretch-activated calcium channels Signup and view all the answers

Which of the following is NOT a role of endothelial cells in the control of tissue blood flow?

Regulating neural influence Signup and view all the answers

What is the half-life of nitric oxide in the blood?

6 seconds Signup and view all the answers

What is the name for the enzyme responsible for synthesizing nitric oxide from arginine and oxygen?

eNOS Signup and view all the answers

What is the term used to describe the immediate rise in blood flow that occurs in most tissues when arterial pressure is rapidly increased?

Auto regulation Signup and view all the answers

What is the role of vasodilator substances in the vasodilator theory for acute local blood flow regulation?

They cause dilation of blood vessels Signup and view all the answers