cAMP shows an oscillatory pattern with odor preference conditioning in neonatal rats

Abstract

Phosphorylation of cyclic adenosine monophosphate (cAMP) response element binding protein (pCREB) is critical in early odor preference learning. However, it is not known how cAMP levels relate to learning. Here, I test cAMP expression during and after the pairing of a conditioned stimulus (CS) odor with an unconditioned stimulus (US), isoproterenol. I find when odor is paired with a dose of isoproterenol previously shown to be optimal for learning, peaks and troughs of cAMP occur at 5 minute intervals. Pairing the odor with a higher isoproterenol dose, that does not produce learning, produces only a linear increase in cAMP. The oscillations only occur when the CS and the optimal US are paired. These data demonstrate a role for cAMP signaling in the acquisition of odor preference learning, and suggest cAMP oscillatory patterns, rather than simple cAMP concentrations, may be required to initiate mammalian associative learning.