Table 3.

Questionable selectivity of AT2 receptor ligands

Compound	Proposed effect on AT2 receptors	Selectivity	References
PD 123177	Antagonist	Blocks AT2 receptors; selectivity for additional receptors or additional activity not studied	Chiu et al. (1990-1991), Wong et al. (1990)
CGP 42112A	Agonist	Not selective for AT2 receptors; binds to uncharacterized receptors in macrophages/microglia	Saavedra and Pavel (2006), Roulston et al. (2004, 2005), Ciuffo and Saavedra (1995), de Oliveira et al. (1994), Viswanathan et al. (1994a, b)
Compound C21	Agonist	Not selective for AT2 receptors; blocks calcium transport into the cell, stimulates AT1 receptors, and reduces affinity of thromboxane A(2) and α-adrenoceptors	Verdonk et al. (2012)

Compounds PD 123177, CGP 42112A, and C21 have been proposed as selective ligands for AT2 receptors. Their selectivity for AT2 receptors is questionable