participates in norepinephrine-epinephrine vasoconstriction involved in regulation of systemic arterial blood pressure phospholipase C-activating G protein-coupled receptor signaling pathway positive regulation of cytosolic calcium ion concentration cell population proliferation positive regulation of MAPK cascade positive regulation of vasoconstriction alpha-1B adrenergic receptor Homo sapiens protein alpha-1B adrenergic receptor (human) alpha-1B adrenoreceptor (human) UniProtKB:P35368 alpha-1B adrenoceptor (human) Category=organism-gene. Reactome:R-HSA-390661 hADRA1B DTO:02100028 protein PR:P35368 ADRA1B An alpha-1B adrenergic receptor that is encoded in the genome of human.