133k views
5 votes
Activation of post-synaptic adrenergic receptors (α1) by sympathetic nerve varicosities results in which of the following?

A) Increased vasoconstriction
B) Decreased vasoconstriction
C) Increased vasodilation
D) Decreased vasodilation

1 Answer

2 votes

Final answer:

Activation of α1-adrenergic receptors by sympathetic nerves leads to increased vasoconstriction due to the triggering of smooth muscle contraction.

Step-by-step explanation:

Activation of post-synaptic adrenergic receptors (α1) by sympathetic nerve varicosities commonly results in vasoconstriction. The binding of ligands such as noradrenaline or adrenaline to these α1-adrenergic receptors, which couple to Gq proteins, leads to an increase in intracellular calcium (Ca²+). This increased Ca²+ concentration causes smooth muscle contraction, which in turn results in the vasoconstriction of arteries and veins. Thus, the specific effect of activating α1-adrenergic receptors by sympathetic nerve action is Increased vasoconstriction (A).

User Chapay
by
8.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.