JBL EMT Practice Exam

Stimulation of alpha-adrenergic receptors results in the constriction of blood vessels. Alpha-adrenergic receptors are predominantly located in the walls of blood vessels. When these receptors are stimulated, it causes smooth muscle contraction in the blood vessel walls, leading to vasoconstriction. This constriction of blood vessels helps in increasing blood pressure by reducing the diameter of the vessels, consequently increasing systemic vascular resistance.

While choices C and D may also be effects of adrenergic stimulation, they are primarily mediated by beta-adrenergic receptors rather than alpha-adrenergic receptors. Choice B is incorrect as stimulation of alpha-adrenergic receptors does not result in the dilation of blood vessels, but rather their constriction.