Question

Which of the following effects is elicited by stimulation of the α1 receptors?

A) Hypertension
B) Hypotension
C) Increased heart rate
D) Dilation of bronchioles
E) None of the above

Answer 1

Stimulation of α1 receptors generally causes vasoconstriction of arteries, leading to an increase in blood pressure, which is why the correct effect is A) Hypertension.

Step-by-step explanation:

The stimulation of α1 receptors leads to several physiological effects, including vasoconstriction of arteries. Specifically, in response to α1 receptor activation by agonists such as noradrenaline, there is an increase in intracellular calcium within smooth muscle cells, which causes these muscles to contract. This type of receptor is coupled to the Gq protein, leading to the activation of phospholipase C (PLC), further increasing intracellular calcium levels. These events predominantly lead to the constriction of smooth muscles in blood vessels, which results in an increase in blood pressure. Therefore, the effect elicited by α1 receptor stimulation is A) Hypertension, due to the vasoconstriction of arteries.