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  #1  
Old 06-28-2011
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Vascular Supine to standing; Cardiovascular physiology

A healthy 30 y/o woman stands up from a supine position. Moving from a supine to a standing position results in a transient decrease in arterial pressure that is detected by arterial baroreceptors located in the aortic arch and carotid sinuses. Which of the following sets of cardiovascular changes is most likely to occur in response to activation of the baroreceptors?

Supine to standing; Cardiovascular physiology-screen-shot-2011-06-28-7.12.15-pm.png
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A) A
B) B
C) C
D) D
E) E
F) F
G) G
H) H
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  #2  
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I would say G.
When the person stands up from supine position low pressure is detected by the baroreceptors. Due to which filling pressure would go down, strength of cardiac contraction would increase to compensate cardiac output and the sympathetic activity increases which will increase heart rate.
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  #3  
Old 06-28-2011
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yap..i"ll also go for G)...
DUE TO MORE VENOUS POOLING OF BLOOD MEAN FILLING PRESSURE GOES DOWN...TO COMPENSATE THIS CO & SYMPATHETIC ACTIVITY GOES UP...
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most likely to occur in response to activation of the baroreceptors?....the answer is not G)...
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Old 06-28-2011
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I will go with A..
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Quote:
Originally Posted by kjain View Post
I will go with A..
Im thinking A) too

but have no idea what Mean Circulating Filling Pressure is
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  #7  
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Quote:
Originally Posted by patelMD View Post
Im thinking A) too

but have no idea what Mean Circulating Filling Pressure is
The mean circulatory filling pressure is defined as the mean pressure that exists in the vascular system if the cardiac output stops and the pressure within the vascular system redistributes. It is an indicator of how full the circulatory system is (i.e. the volume of blood in the system compared to the capacity of the system), and is influenced by the volume of circulating blood and the smooth muscle tone in the walls of the venous system (which determines the capacity of the system).
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Old 06-28-2011
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Quote:
Originally Posted by bebix View Post
The mean circulatory filling pressure is defined as the mean pressure that exists in the vascular system if the cardiac output stops and the pressure within the vascular system redistributes. It is an indicator of how full the circulatory system is (i.e. the volume of blood in the system compared to the capacity of the system), and is influenced by the volume of circulating blood and the smooth muscle tone in the walls of the venous system (which determines the capacity of the system).
is it A???
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I will go with A
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I am going with A.. I think I hav solved similar kind of ques..!!
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i think A too
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Post answer is A

the answer is(A) .....because when changing the body posture form lying to standing ....there will be a sudden drop in the arterial blood pr. this will lead to activation of baroreceptors...and the baroreceptors in turn will lead to sympathetic activation... wich will lead to increase in the strenght of cardiac contraction and circulatory filling pressure ....is that correct....??????

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I go with A
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Correct Answer correct answer

The correct answer is A)

Activation of the baroreceptors leads to an increase in sympathetic activity, which in turn increases heart rate, strength of cardiac contraction, and constriction of arterioles and veins. The increase in venous constriction results in an increase in mean circulatory filling pressure, venous return and cardiac output.
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  #15  
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great question
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I am a fan of bebix`s questions.Its always the first thing i see.
Thanks once again.
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great my answer was true ....
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Warning! I think its [A]

As "the smooth muscle tone in the walls of the venous system" increases with increased sympathetic tone so mean circulatory filling pressure should go up.
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  #19  
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yes, his qs are fun to do..and tough..makes me think!
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Quote:
Originally Posted by bebix View Post
A healthy 30 y/o woman stands up from a supine position. Moving from a supine to a standing position results in a transient decrease in arterial pressure that is detected by arterial baroreceptors located in the aortic arch and carotid sinuses. Which of the following sets of cardiovascular changes is most likely to occur in response to activation of the baroreceptors?

Attachment 1628
click image to enlarge

A) A
B) B
C) C
D) D
E) E
F) F
G) G
H) H
i will go with A..because in response to pooling of blood in veins,..there is also compensatory venoconstriction..i read it somewhere..so the effective volume in the circulation will also increase..
i hope i am not wrong..
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