What is one of the effects of Alpha 1 blockade by Labetalol?

Alpha 1 blockade by Labetalol leads to the promotion of dilation of arterioles and veins. Labetalol is a mixed alpha and beta blocker, which means it simultaneously affects both alpha-adrenergic and beta-adrenergic receptors. When it blocks alpha-1 receptors, the vascular smooth muscle relaxes, resulting in vasodilation. This dilation decreases systemic vascular resistance, which can help lower blood pressure.

By promoting vasodilation, Labetalol effectively reduces the constriction of blood vessels, thus facilitating improved blood flow. This property is particularly beneficial in conditions like hypertension, where reducing vascular resistance is essential for managing blood pressure levels.

In contrast, the other responses do not accurately describe the effects of Alpha 1 blockade. Increased heart rate typically occurs when beta-1 receptors are stimulated, not blocked. Decreased dilation of arterioles is contrary to the effect of alpha-1 blockade, which actually enhances dilation. Reduced capillary permeability is not a direct action of alpha-1 blockade and is more associated with other mechanisms.