β-Adrenoceptor activation enhances L-type calcium channel currents in anterior piriform cortex pyramidal cells of neonatal mice: implication for odor learning

Early odor preference learning occurs in one-week-old rodents when a novel odor is paired with a tactile stimulation mimicking maternal care. beta-Adrenoceptors and L-type calcium channels (LTCCs) in the anterior piriform cortex (aPC) are critically involved in this learning. However, whether beta-adrenoceptors interact directly with LTCCs in aPC pyramidal cells is unknown. Here we show that pyramidal cells expressed significant LTCC currents that declined with age. beta-Adrenoceptor activation via isoproterenol age-dependently enhanced LTCC currents. Nifedipine-sensitive, isoproterenol enhancement of calcium currents was only observed in post-natal day 7-10 mice. APC beta-adrenoceptor activation induced early odor preference learning was blocked by nifedipine coinfusion.