The function of ADRB1 (adrenoceptor beta 1, Ensembl gene identifier ENSG00000043591) is as follows. G protein-coupled receptor for catecholamines that couples to G(s) proteins to activate adenylate cyclase and cAMP-dependent pathway (PubMed:10212248, PubMed:12391161, PubMed:15358775). Binds epinephrine and norepinephrine with approximately equal affinity (PubMed:33093660). Mediates the activation of Ras via binding with cAMP-dependent RAPGEF2 (PubMed:12391161). As part of the sympathetic nervous system, plays a role in the physiologic regulation of cardiac functions such as stimulation of cardiomyocyte contraction (PubMed:11052857). Also delivers proapoptotic signals in cardiomyocytes (By similarity). Involved in the regulation of sleep/wake behaviors (PubMed:11854867, PubMed:31473062). {ECO:0000250|UniProtKB:P34971, ECO:0000269|PubMed:10212248, ECO:0000269|PubMed:11052857, ECO:0000269|PubMed:11854867, ECO:0000269|PubMed:12391161, ECO:0000269|PubMed:15358775, ECO:0000269|PubMed:31473062, ECO:0000269|PubMed:33093660}.