simple cardiovascular/nervous question

[miringains]

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So the sympathetic nervous system increases your blood pressure, but causes Vasodilation.

I was doing a TPR test and one of the questions kept going on about how vasoconstriction is actually what causes blood pressure increases..... which makes sense since there is less area.

How does the sympathetic nervous system increase blood pressure while causing vasodilation? Or is the vasdoilation only to skeletal muscles, whereas vasocosntriction also occurs during sympathetic stimulation, but occurs in places like the gut and stuff? 😳


MCAT in 2 weeks!... haha 🙁 you would think being a bio major this would be my easiest section, but nope PS ftw

Or is the increase in blood pressure due to the SA node being stimulated faster? And nothing to do with vasodilation/constriction?



mind = blown

 

[shaboobly]

the muscles need more oxygen because sympathetic (fight or flight) readies your body for strenuous activity. this results in vasodilation for more oxygen transport and the hormones associated with the response will cause the heart to beat faster, also increasing the amount of oxygen transferred and increasing the bp.

the digestive system is innervated by parasympathetic nerves which are inhibited during the response and causes constriction of the "non essential" parts of your body during a time to fight.

 

[miringains]

the muscles need more oxygen because sympathetic (fight or flight) readies your body for strenuous activity. this results in vasodilation for more oxygen transport and the hormones associated with the response will cause the heart to beat faster, also increasing the amount of oxygen transferred and increasing the bp.

the digestive system is innervated by parasympathetic nerves which are inhibited during the response and causes constriction of the "non essential" parts of your body during a time to fight.

thanks, so the incrase in blood pressure is actually due mainly due to the hormones / more oxygen transport, rather than the vasdilation itsself? Because generally speaking take a human, vasoconstrict the arteries of one, and vasodilate the other. The vasoconstricted human would theoretically have a higher bp correct? That is what my book is teaching me

 

[shaboobly]

yes constriction increases bp.

 

[JaBoomDay]

thanks, so the incrase in blood pressure is actually due mainly due to the hormones / more oxygen transport, rather than the vasdilation itsself? Because generally speaking take a human, vasoconstrict the arteries of one, and vasodilate the other. The vasoconstricted human would theoretically have a higher bp correct? That is what my book is teaching me

The contractility of the heart becomes stronger/more forceful which is what increases the blood pressure. This is due to the effect of hormones like adrenaline.

During fight or flight (sympathetic nervous response), there is vasoconstriction and vasodilation happening simultaneously but in different parts of the body. There is vasodilation to the muscles to allow for increased oxygen transport but there's vasoconstriction to the digestive system to shunt blood away to flow to more vital organs and the muscles to prepare for flight.

 

[JaBoomDay]

How does the sympathetic nervous system increase blood pressure while causing vasodilation? Or is the vasdoilation only to skeletal muscles, whereas vasocosntriction also occurs during sympathetic stimulation, but occurs in places like the gut and stuff? 😳

👍 That's correct.

Or is the increase in blood pressure due to the SA node being stimulated faster? And nothing to do with vasodilation/constriction?

SA node being stimulated faster (increased conduction between SA and AV node) would only increase the heart rate.

 

[miringains]

i love you guys <3

 

[flashlightpen]

i love you guys <3

We love you, too! 😍

 

[JaBoomDay]

i love you guys <3

Aww you gave me a warm fuzzy inside! 😀