Exercise and skeletal muscle blood flow Q. I thought I understood it...

[Bleepbloopblop]

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During exercise "as skeletal muscle arterioles dilate, arterioles to certain other areas help compensate by constricting. The primary organs for this sympathetic vasoconstriction are the gut, skin and inactive skeletal muscles."
Cardiovascular Response to Exercise

What causes vasoconstriction in inactive skeletal muscles? I understand that local mediators in active skeletal muscles (ie. ADP, K+, NO) cause vasodilation, but in inactive skeletal muscles, wouldn't sympathetics cause vasodilation too since they have a higher beta 2 receptor density? I understand that in other organs, like GI and skin, sympathetic stimulation affects alpha1 predominantly which is what causes vasoconstriction and redistribution of blood to active skeletal muscles, but in those organs beta 2 receptors are quickly overcome due to lower beta2 density (right?)

Thanks for any input.

 

[AnatomyGrey12]

In resting skeletal muscle the sympathetic nerves act on the alpha 1 receptors on the arterioles causing vasoconstriction.

 

[mehc012]

In resting skeletal muscle the sympathetic nerves act on the alpha 1 receptors on the arterioles causing vasoconstriction.

This. Sympathetic stimulation causes vasodilation everywhere, but in active skeletal muscles the local vasodilators overwhelm that effect.