There are three known mammalian tachykinin receptors termed NK₁, NK₂ and NK₃. All are members of the 7 transmembrane G-protein coupled receptor family and induce the activation of phospholipase C, producing inositol triphosphate (so called G_q-coupled).

Inhibitors of NK-1, known as NK-1 receptor antagonists, can be used as antiemetic agents, such as the drug aprepitant.^[1]

The genes and receptor ligands are as follows:^[2]

(Hökfelt et al., 2001; Page, 2004; Pennefather et al., 2004; Maggi, 2000)

• Substance P
• G protein coupled receptors