“…NE has differential effects on target neurons depending on the adrenergic receptor subtype(s) present. Adrenergic receptors are G-protein-coupled receptor (GPCRs) that can be broadly classified as α1, α2, or β receptors, each of which has three subtypes (α1A-C, α2A-C, and β1-3) (for review, see (Lefkowitz, 1990;Strosberg, 1993)). Herbert & Flügge, 1995;Scheinin et al, 1994;Unnerstall, Fernandez, & Orensanz, 1985).…”