Question

What is the adrenergic receptor Gaq?

Answer 1

The adrenergic receptors are mainly G protein-coupled receptors and these are targets of the catecholamines, such as norepinephrine and epinephrine. These G protein coupled receptors are categorise into two main subunits which are α and β, with several subtypes. Out of these subtypes, α receptors have the subtypes α₁ which is a G_q coupled receptor.

When norepinephrine stimulates alpha1-adrenergic receptors, it leads to the activation of a Gq coupling protein. The alpha subunit of this G protein then activates the effector- phospholipase C (PLC), which leads to the release of IP3 (inositol 1,4,5-trisphosphate) and DAG (diacylglycerol) from phosphatidylinositol 4,5-bisphosphate (PtdIns 4,5-P2). Then IP3 and DAG proceed their own pathway.

In a nutshell, Gaq is an adrenergic receptor which is stimulated by catecholamines and works by activating PLC.