Which drug class does not pertain to constricting vessel lumens?

The drug class that does not pertain to constricting vessel lumens is vasodilators. Vasodilators specifically work to relax and widen blood vessels, which leads to an increase in blood flow and a decrease in blood pressure. This action directly opposes the constriction of vessel lumens, making vasodilators unique compared to the other classes mentioned.

Adrenergic agents, beta-blockers, and alpha-agonists all involve mechanisms that can lead to the constriction of blood vessels under certain conditions. Adrenergic agents generally stimulate the sympathetic nervous system, which can result in vasoconstriction, particularly through the activation of alpha-adrenergic receptors. Beta-blockers, while primarily used to lower blood pressure and heart rate, can indirectly affect vascular tone. Alpha-agonists specifically trigger alpha receptors that lead to vasoconstriction, thereby narrowing blood vessel lumens.

In summary, vasodilators are characterized by their ability to promote the relaxation of blood vessels, which categorically distinguishes them from the other drug classes that are associated with vessel constriction.