Examples of cyclic nucleotides are cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate
The fourth treatment, theophylline, a phosphodiesterase inhibitor that prevents the breakdown of cyclic adenosine monophosphate
(the second messenger produced by adenylyl cyclase), was the only agent that restored cell signaling to normal or supranormal levels but did so at further cost to cell replication.
The mutation leads to a loss of guanosine triphosphatase activity and thus to adenyl cyclase overactivity and subsequent overproduction of cyclic adenosine monophosphate
While it is true that caffeine is an adenosine receptor antagonist, it also increases cyclic adenosine monophosphate
, (cAMP) which has antiproliferative and immunosuppressive effects.
Benowitz' team injected the animals' eyes with oncomodulin in slow-release capsules, along with a chemical called cyclic adenosine monophosphate
that's known to prompt nerve cells to respond to other growth factors.