Description
The α1-adrenergic receptor (AR) family consists of three closely related gene products (α1A, α1B, and α1D). They mediate the actions of norepinephrine (NE) and epinephrine in sympathetically innervated tissues and brain. α1-ARs belong to the G protein-coupled receptor family and consist of single polypeptide chains that are predicted to form seven transmembrane spanning domains. With similar pharmacological and signaling properties, α1-AR subtypes act through Gq/11 proteins to activate phospholipase C, increase inositol 1,4,5-trisphosphate production, and increase intracellular Ca2+.