Firing of carotid sinus and aortic arch

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Firing of carotid sinus and aortic arch

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Bela
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04/27/04 - 12:52 AM

1) Scientist stimulates the afferent portions of CN 9 & 10. What is the outcome of this manipulation?
a) Brady w/ HTN
b) Brady w/hypoT
c) Tachy w/HTN
d) Tachy w/hypoT
e) Sinus arrhythmia w/hypoT

Please explain ur reasoning! Thnx!

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Colombia
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04/27/04 - 08:02 AM

Brady and hypot 'cause increase firing rate of the carotid sinus which carries information to the vasomotor center of the brain stem. As a result, trher an increase in the parasymphatetic stimulation.

canstep1
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04/27/04 - 05:40 PM

b) brady with hypo/t

rubensssss
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04/30/04 - 10:03 PM

Answer B

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mjl1717
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10/10/04 - 12:35 AM

To clarify this:

Its the GVA component of CN IX and
*the GVE component of CN X that causes this carotid sinus reflex!
(bradycardia with possible hypotension)
*CN X does not have an afferent connection to the heart
As stated the medulla oblongata AND the nucleus solitarius come into play here with this reflex. The actual cardioinhibitory center is in the nucleus ambiguus. :idea:

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