10. What are some metabolic and myogenic controls of LOCAL blood flow? (fig 19.15).
Why is angiogenesis important to local tissue perfusion long-term? (p.713) (Why are
smokers at higher risk of death from heart attack than non-smokers? Hint: recall effect
on RBC, and on angiogenesis)
Give this one a try later!
, Metabolic controls of local blood flow is nitric oxide.
Myogenic controls of local blood flow are caused by stretch so blood
pressure goes up LOCALLY and the vessels constrict locally to try and stop
blood flow but instead BP goes up even more.
Angiogenesis is important to local tissue profusion because this is when the
number if blood vessels in the region increses and existing vessels enlarge.
Angiogenesis is common in the heart when a coronary vessel is partially
occluded.
One example is blood flow in the heart tissue, such as collateral formation
so the heart tissue doesn't die.
Smokers are at higher risk of death from heart attack than nonsmokers
because they can't get angiogenesis to happen (so they don't have
collateral routes when another is blocked). Also oxygen cannot bind to
RBC's because carbon monoxide binds to the oxygen site.
8. Spend a little time on Figure 19.11. Be able to predict what will happen if there is a)
fluid loss, b) excess sweating, c) exercise or other sympathetic activation, d) someone
puts on a lot of weight.
Give this one a try later!
If there is fluid loss the blood volume will go down, blood pressure goes
down, venous return goes down, heart rate may increase (but it will be a
thready pulse) and then it goes back to very low and your kidneys will try to
increase blood volume by retaining salt and water.
If you have excess sweating, your blood volume goes down, BP goes
down, venous return goes down, and heart rate goes down.
Exercise or other sympathetic activation, will decrease blood Ph, oxygen
goes down, CO2 goes up, which will stimulate cardioacceleratory centers
(from chemoreceptors) so HR goes up, diameter constriction overall
occurs (exception is in skeletal muscles because it will demand oxygen),
and overall resistance goes up and CO goes up.
If someone puts on a lot of weight, blood vessels length goes up and so
does resistance (CO would go down and stroke volume would go down,
heart rate would go up.)
, 9. Be able to trace the action potential of an autorhythmic cell, and also a cardiac
contractile cell. What ions are involved in the depolarization and repolarization in
each cell type? What event and what structures connect the depolarization of these
two cell types? (Use IP-10!!!)
Give this one a try later!
Autorhythmic cell:
Na+ is leaking in (pacemaker potential)
Ca2+ channels open, flows in from extracellular fluid
Causes a depolarization that goes through the gap junctions with positive
ions to the contractile cells.
Repolarization occurs, K+ flows out
Contractile cell:
Autorhythmic cell sends depolarization and positive ions through gap
junction
Na+ channels open, LOTS and LOTS of Na+ comes in
Depolarization occurs
Contraction occurs
Plateau phase occurs as calcium channels open and more calcium comes
in
Repolarization occurs, K+ goes out
9. What are hypotension and hypertension? Sometimes, they are simply normal
effects of daily activity: When are they potentially problems? What is the difference
between primary (essential) Hypertension and secondary hypertension? What are
some causes? (p. 710-711)
Give this one a try later!
Why is angiogenesis important to local tissue perfusion long-term? (p.713) (Why are
smokers at higher risk of death from heart attack than non-smokers? Hint: recall effect
on RBC, and on angiogenesis)
Give this one a try later!
, Metabolic controls of local blood flow is nitric oxide.
Myogenic controls of local blood flow are caused by stretch so blood
pressure goes up LOCALLY and the vessels constrict locally to try and stop
blood flow but instead BP goes up even more.
Angiogenesis is important to local tissue profusion because this is when the
number if blood vessels in the region increses and existing vessels enlarge.
Angiogenesis is common in the heart when a coronary vessel is partially
occluded.
One example is blood flow in the heart tissue, such as collateral formation
so the heart tissue doesn't die.
Smokers are at higher risk of death from heart attack than nonsmokers
because they can't get angiogenesis to happen (so they don't have
collateral routes when another is blocked). Also oxygen cannot bind to
RBC's because carbon monoxide binds to the oxygen site.
8. Spend a little time on Figure 19.11. Be able to predict what will happen if there is a)
fluid loss, b) excess sweating, c) exercise or other sympathetic activation, d) someone
puts on a lot of weight.
Give this one a try later!
If there is fluid loss the blood volume will go down, blood pressure goes
down, venous return goes down, heart rate may increase (but it will be a
thready pulse) and then it goes back to very low and your kidneys will try to
increase blood volume by retaining salt and water.
If you have excess sweating, your blood volume goes down, BP goes
down, venous return goes down, and heart rate goes down.
Exercise or other sympathetic activation, will decrease blood Ph, oxygen
goes down, CO2 goes up, which will stimulate cardioacceleratory centers
(from chemoreceptors) so HR goes up, diameter constriction overall
occurs (exception is in skeletal muscles because it will demand oxygen),
and overall resistance goes up and CO goes up.
If someone puts on a lot of weight, blood vessels length goes up and so
does resistance (CO would go down and stroke volume would go down,
heart rate would go up.)
, 9. Be able to trace the action potential of an autorhythmic cell, and also a cardiac
contractile cell. What ions are involved in the depolarization and repolarization in
each cell type? What event and what structures connect the depolarization of these
two cell types? (Use IP-10!!!)
Give this one a try later!
Autorhythmic cell:
Na+ is leaking in (pacemaker potential)
Ca2+ channels open, flows in from extracellular fluid
Causes a depolarization that goes through the gap junctions with positive
ions to the contractile cells.
Repolarization occurs, K+ flows out
Contractile cell:
Autorhythmic cell sends depolarization and positive ions through gap
junction
Na+ channels open, LOTS and LOTS of Na+ comes in
Depolarization occurs
Contraction occurs
Plateau phase occurs as calcium channels open and more calcium comes
in
Repolarization occurs, K+ goes out
9. What are hypotension and hypertension? Sometimes, they are simply normal
effects of daily activity: When are they potentially problems? What is the difference
between primary (essential) Hypertension and secondary hypertension? What are
some causes? (p. 710-711)
Give this one a try later!
