β1-Adrenoceptor or α1-adrenoceptor activation initiates early odor preference learning in rat pups: Support for the mitral cell/cAMP model of odor preference learning

摘要

We proposed that mitral cell β1-adrenoceptor activation mediates rat pup odor preference learning. Here we evaluate β1-, β2-, α1-, and α2-adrenoceptor agonists in such learning. The β1-adrenoceptor agonist, dobutamine, and the α1-adrenoceptor agonist, phenylephrine, induced learning, and both exhibited an inverted U-curve dose-response relationship to odor preference learning. Phenylephrine-induced learning occurred in the presence of propranolol to prevent indirect activation of β-adrenoceptors. α1-Adrenoceptor mediation may represent a novel mechanism inducing learning or may increase cAMP in mitral cells via indirect activation of GABA_B receptors. Neither the β2-adrenoceptor agonist, salbutamol, nor the α2-adrenoceptor agonist, clonidine, induced learning.