There are several different secondary messenger systems (cAMP system, phosphoinositol system, and arachidonic acid system), but they all are quite similar in overall mechanism, although the substances involved and overall effects can vary.
Hai varios sistemas distintos de segundos mensaxeiros (AMPc, sistema do fosfatidilinositol, e do ácido araquidónico), pero todos teñen un mecanismo xeral moi similar, aínda que as substancias implicadas e os efectores son diferentes.