The mechanism of action of sodium nitroprusside is?
Increased cAMP
Increased guanylate cyclase
Calcium channel blockage
IC channel opener
Ans. is 'b' i.e., Increases Guanyl Cyclase o "Nitroprusside dilates both aerial and venous vessels, resulting in reduced peripheral vascular resistance and venous return. The action occurs as a result of activation of guanylyl cyclase, either release of nitric oxide or by direct stimulation of enzyme. The result is increased intracellular cGMP, which relaxes vascular smooth muscle".