Description
Adrenoceptors are 7-transmembrane receptors which mediate the central and peripheral actions of the neurotransmitter, noradrenaline (norepinephrine), and the hormone and neurotransmitter, adrenaline (epinephrine). Based on both pharmacological and molecular evidence, they are divided into three major types – α1, α2, and β. The α2 adrenoceptors include 3 subtypes – α2A, α2B, and α2C – each of which couples to Gi/o protein primarily.
The α2B adrenoceptors (ADRA2B) is expressed in the kidney, liver, brain, lung, heart, and skeletal muscle. The development of α2B and α2C knock-out mice has shown that these two subtypes are not involved in the central hypotensive response to α2 agonists.