Bradykinin receptor B2 (B2R) (B2R)

The Bradykinin receptor B2 (B2R) is a G protein-coupled receptor that serves as the primary mediator for the physiological and pharmacological effects of bradykinin and kallidin [UniProt P30551]. These peptides are generated endogenously from kininogens by the action of kallikrein enzymes within the kallikrein-kinin system [IUPHAR Guide to Pharmacology]. Unlike the B1 receptor, which is typically induced during tissue injury or inflammation, the B2 receptor is constitutively expressed in various tissues, including the vascular endothelium, smooth muscle, and sensory neurons [PubMed: 15128905]. Activation of the B2 receptor triggers signaling pathways that lead to potent vasodilation, increased vascular permeability, and the stimulation of nociceptors, making it a central player in the inflammatory response and blood pressure regulation [PubMed: 15128905]. In clinical pathology, the B2 receptor is a major therapeutic target for hereditary angioedema (HAE), a condition characterized by excessive bradykinin production leading to severe, potentially life-threatening localized swelling [StatPearls: Hereditary Angioedema]. Pharmacological targeting of the B2 receptor primarily involves the use of selective antagonists, such as icatibant, which provide rapid relief during acute HAE attacks by blocking the binding of endogenously generated kinins [PubMed: 21633164]. Beyond HAE, the receptor is also implicated in other inflammatory conditions, cardiovascular regulation, and the pathophysiology of certain viral infections like COVID-19 [PubMed: 32735825]. Safety concerns for B2 receptor modulation include potential hypotension and interactions with ACE inhibitors, which can exacerbate bradykinin-mediated side effects [PubMed: 11588311].

Other names

BDKRB2BK-2 receptorBK2RB2 bradykinin receptorBradykinin B2 receptorBradykinin B2 receptor – via endogenously generated kinins

Competitive antagonism of the B2 receptor to block the binding of endogenously generated bradykinin and kallidin, thereby preventing vasodilation, edema, and pain [PubMed: 21633164].