Sympathetic Nervous System and Vasoconstriction / Vasodilation

[esob]

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I was going over my notes and realize I have a discrepancy. My impression, at least for the MCAT, is that during a fight or flight response the sympathetic nervous system would cause vasoconstriction to the organs. A couple of answers in similar threads seem to reiterate this. However, an explanation offered in the AAMC biopack 2 states that the sympathetic NS "causes dilation of the vessels that supply the internal organs".

So which is it?

PS: the last thread I could find about this topic was a couple years old so I figured I would post a new one instead of necro'ing an old one.

 

[CommyO]

I was going over my notes and realize I have a discrepancy. My impression, at least for the MCAT, is that during a fight or flight response the sympathetic nervous system would cause vasoconstriction to the organs. A couple of answers in similar threads seem to reiterate this. However, an explanation offered in the AAMC biopack 2 states that the sympathetic NS "causes dilation of the vessels that supply the internal organs".

So which is it?

PS: the last thread I could find about this topic was a couple years old so I figured I would post a new one instead of necro'ing an old one.

Think about it;
the sympathetic NS would cause vasocontriction in those organs responsible for parasympathetic functions such as salivary glands, vessels responsible for peristalsis in the digestive tract, and even erectile tissues

however; blood flow increases to organs such as the limbs, heart, and lungs to replenish oxygenated blood (also skin sweat glands)

In summary; it's not a all-or-nothing answer and depends on what process the organ facilitates

 

[esob]

Think about it;
the sympathetic NS would cause vasocontriction in those organs responsible for parasympathetic functions such as salivary glands, vessels responsible for peristalsis in the digestive tract, and even erectile tissues

however; blood flow increases to organs such as the limbs, heart, and lungs to replenish oxygenated blood (also skin sweat glands)

In summary; it's not a all-or-nothing answer and depends on what process the organ facilitates

That's about what I figured but AAMC made the blanket statement that it caused dilation to the internal organs and I had read that not all the organs would be affected the same. I just wanted to verify that.