The dopamine receptors are a class of G-protein coupled receptors with dopamine as their endogenous ligand.
The D1 receptor is coupled to adenylate cyclase via a stimulatory G protein
The D2 receptor is negatively coupled to adenylate cyclase via an inhibitory G protein
The D3 receptor is negatively coupled to adenylate cyclase via an inhibitory G protein
The D4 receptor is negatively coupled to adenylate cyclase via an inhibitory G protein
The D5 receptor is coupled to adenylate cyclase via a stimulatory G protein
