Viagra, Cialis and other drugs known to alleviate 'erectile dysfunction' increase blood flow by:

Question

Viagra, Cialis and other drugs known to alleviate 'erectile dysfunction' increase blood flow by:

Increasing the concentration of cyclic GMP in smooth muscle

Increasing phosphodiesterase (PDE-5) activity in smooth muscle

Increasing the concentration of the enzyme guanylate cyclase in smooth muscle

Answer 1

Increasing the concentration of cyclic GMP in smooth muscle is the correct answer. Viagra, Cialis, and similar drugs are phosphodiesterase type 5 (PDE-5) inhibitors. By inhibiting the action of PDE-5, these drugs prevent the breakdown of cyclic GMP, which is responsible for relaxing smooth muscle and increasing blood flow to the erectile tissue of the , thus helping to achieve and maintain an erection.