nbme19/Block 2/Question#13

25 yo man, exercise test. Most likely physiologic changes

Arteriolar diameter increased; Tissue adenosine concentration increased; Vascular conductance increased

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submitted by ajguard26,

As the muscle works and breaks down ATP, adenosine is produced, leading to an increase in the tissues. This increased adenosine causes vasodilation, which in turn increases vascular conductance (the flow of a volume of blood through the vasculature).

Although you may think muscle contraction may lead to a decrease in flow through the vessel(s) by squeezing down on them, this mechanism is overcome by the increased cardiac output from the heart.