Behavioral relevance of norepinephrine is associated with neuronal processing underlying arousal, affect, attention, learning and memory, and is associated with β-adrenergic modifications of neuronal activation in the hippocampal formation. This study utilized l-isoproterenol to initiate pathway-specific activation of afferents to hippocampal CA1 pyramidal cells. The consistent effects of l-isoproterenol on the initiation of action potentials to field CA1 pyramidal neurons to single-pulse stimulation was repeatedly associated with the activation of the Schaffer collateral pathway. In contrast, l-isoproterenol plus single-pulse stimulation never elicited action potential initiation of the perforant pathway to CA1. We interpret these results as indicating that β-adrenergic modification underlies the augmentation of information processing via the Schaffer collateral pathway in the trisynaptic circuit vs the direct perforant pathway.
- hippocampal field CA1
- information processing
- β-adrenergic pathway specificity