-2
$\begingroup$

Recently I studied that cAMP which is a 2° messenger can cause various physiolocal changes under the action of proper hormones. Now cAMP is degraded by phosphodiesterase and this ceases the actions. Viagra drugs like sildenafil are phophodiesterase inhibitors and therefore prolong cAMP action. Also caffeine inhibits phosphodiesterase and therefore it should cause a similar phenomenon. But does it actually happen? Or some other mechanism stop it from happening. What are those mechanisms?

$\endgroup$
2
  • 2
    $\begingroup$ Is sildenafil a "phophodiesterase inhibitor"? Or is it a specific inhibitor of a particular phophodiesterase? If the latter, which one? How potent is it vs. caffeine? $\endgroup$ – Bryan Krause Feb 24 at 20:12
  • $\begingroup$ To put it in everyday terms: caffeine raises blood pressure, and this is pretty much the same effect as that of viagra, just less specific and less long-lasting. $\endgroup$ – Vadim Feb 25 at 1:53
1
$\begingroup$

Not much luck there. Although caffeine, sildenafil and cGMP share a basic ring structure, the specificity and potency of caffeine for PDE5 is rather underwhelming:

On the basis of comparative IC50 values, the potency of sildenafil is about 1 million times higher than that of caffeine (Corbin and Francis, 1999).

$\endgroup$
1
  • $\begingroup$ This is a lot of coffee. $\endgroup$ – Winston Feb 24 at 21:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.