Angiotensin II receptor type 2 (IPR000147)
Short name: ATII_AT2_rcpt
Overlapping homologous superfamilies
Angiotensin II is a blood-borne hormone produced in the circulation, it is also formed in many tissues such as the brain, kidney, heart, and blood vessels, where angiotensin II functions as a paracrine and autocrine hormone. The known actions of angiotensin II are mediated through two angiotensin receptor subtypes, Angiotensin II receptor 1 and angiotensin II receptor 2, which are members of the seven transmembrane rhodopsin-like G-protein coupled receptor family. These subtypes are important in the renin-angiotensin system, as they are responsible for the signal transduction of the vasoconstricting stimulus of the main effector hormone, angiotensin II [PMID: 17346243]. They also stimulate increased fluid intake and regulate the neuroendocrine system [PMID: 17346243].
This entry represents angiotensin II receptor type 2 (AT2), which plays an important role in the CNS and cardiovascular functions mediated by the renin-angiotensin system. The AT2 receptor is highly expressed in various foetal tissues, with lower levels in the brain and reproductive tissues [PMID: 8725391]. It appears to be up-regulated after vascular injury, myocardial infarction, cardiac failure or wound healing [PMID: 9851935, PMID: 10024335, PMID: 10395402, PMID: 8809509]. Depending on the tissue type, activation of the AT2 receptor also appears to stimulate intracellular mechanisms involving Tyr and Ser/Thr phosphatases, which leads to the inactivation of the AT1 and growth factor activated kinases [PMID: 10652498, PMID: 10339618, PMID: 8552595, PMID: 9228085, PMID: 11116149, PMID: 11566906, PMID: 11714657, PMID: 11910305]. However, when inducing cell differentiation, the AT2 receptor can also stimulate MAP kinases Erk1/Erk2 [PMID: 10891597]. As a consequence, there is an inactivation of MAP kinase, promotion of apoptosis, repolarization trough opening of delayed-rectifier K+ channels and calcium and voltage activated potassium channel, closing of T -type Ca2+ channels and vasodilation [PMID: 7829501, PMID: 11723025, PMID: 8552595, PMID: 7840157]. Through its phosphatase activity, the AT2 receptor regulates the NF-kappaB pathway [PMID: 10864905, PMID: 14500552] and interferes with the inflammatory process [PMID: 11723025, PMID: 11788460]. The AT2 receptor does not require receptor phosphorylation or heterotrimeric G alpha/beta/gamma protein to be active [PMID: 12221292].
GO:0004945 angiotensin type II receptor activity
GO:0016021 integral component of membrane