QuestionSBA
QuestionChoice
This is incorrect. NO does not inhibit the action of calmodulin. Its primary mechanism of action is through the activation of guanylate cyclase and the subsequent increase in cGMP.
10026229
e
NO inhibits the action of the calcium-binding protein calmodulin, thereby reducing intracellular calcium levels
QuestionChoice
This is incorrect. NO does not directly bind to calcium ions. Its primary mechanism of action is through the activation of guanylate cyclase and the subsequent increase in cGMP.
10026226
b
NO directly binds to calcium ions, neutralizing them and preventing them from contributing to cellular processes
QuestionChoice
This is correct. Nitric oxide activates guanylate cyclase, which converts GTP to cGMP. Increased cGMP then activates protein kinase G (PKG), which acts to lower intracellular calcium through various mechanisms.
10026225
a
NO activates guanylate cyclase, which converts GTP to cGMP
QuestionChoice
This is incorrect. NO does not increase the activity of the Na+/K+ ATPase pump. Its primary mechanism of action is through the activation of guanylate cyclase and the subsequent increase in cGMP.
10026228
d
NO increases the activity of the Na+/K+ ATPase pump, indirectly leading to a decrease in intracellular calcium
QuestionChoice
This is incorrect. NO does not block calcium release from the endoplasmic reticulum. NO does not directly bind to calcium ions. Its primary mechanism of action is through the activation of guanylate cyclase and the subsequent increase in cGMP.
10026227
c
NO blocks the release of calcium from the endoplasmic reticulum, thus reducing the amount of calcium available in the cell
Concept
Chapter
2693
3809
Structure and physiology of blood vessels
Topic
159
Cardiovascular physiology
17643
A 60 year old patient with a history treatment-resistant of hypertension is reviewed in a cardiology clinic. The cardiologist explains the role of Nitric Oxide (NO) in regulating blood pressure and mentions that NO causes vasodilation by reducing intracellular calcium.

By which of the following mechanisms does NO reduce intracellular calcium?
a