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Old 08-25-2016
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Default please explain ans pharma

which receptors are not involved in reflex bradycardia or tachycardia due to increase or decrease in bp respectively? i am not able to understand why only some receptors are involved in the reflex? please explain which ones are and which ones aren't? and why is that so?
thank you
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Old 09-04-2016
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Stethoscope

Quote:
Originally Posted by lavenderfreesia View Post
which receptors are not involved in reflex bradycardia or tachycardia due to increase or decrease in bp respectively? i am not able to understand why only some receptors are involved in the reflex? please explain which ones are and which ones aren't? and why is that so?
thank you

The ones present in the blood vessels. If u constrict/dilate a blood vessel that will be perceived by the baroreceptors which will send this signal to the vasomotor center in the brain, which will then trigger the SANS or PANS that will work in the heart by either causing tachycardia or bradycardia.
So to answer your question the only receptors INVOLVED will be: alpha 1 (constriction) and beta 2 (dilation)
I hope i cleared that up for you
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Old 09-06-2016
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Star thank you

thankyou so much! it helped a lot
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Old 09-07-2016
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Previous answer is incomplete:
Bradycardia and tachycardia are autonomic system responses. First of all, there has to be an initiating event like hypotension or hypertension; the receptors that are involved in DETECTING changes in pressure are the BARORRECEPTORS, the most important ones are the carotid ones which communicate to the brainstem through CN IX, then the aortic ones which communicate through CN10, the solitary nucleus senses this signals and then the ambiguus and dorsal nucleus of vagus send signals through the sympathetic system to activate the heart via norepinephrine on BETA 1 receptors, some of this norepinephrine goes systemic and activates ALPHA 1 on the blood vesses.
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Old 09-08-2016
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Quote:
Originally Posted by zamoramed View Post
Previous answer is incomplete:
Bradycardia and tachycardia are autonomic system responses. First of all, there has to be an initiating event like hypotension or hypertension; the receptors that are involved in DETECTING changes in pressure are the BARORRECEPTORS, the most important ones are the carotid ones which communicate to the brainstem through CN IX, then the aortic ones which communicate through CN10, the solitary nucleus senses this signals and then the ambiguus and dorsal nucleus of vagus send signals through the sympathetic system to activate the heart via norepinephrine on BETA 1 receptors, some of this norepinephrine goes systemic and activates ALPHA 1 on the blood vesses.
Everything you have written here is correct but all the details u added are anatomic ones which wasn't the point in his question (ans pharma). And i am pretty sure he was asking about the receptors triggering the reflex (those in the vessels) so the only missing detail in my response would be the M3 receptor found in the vessels (nothing to activate it physiologically)
Anyway, great anatomic detail
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