Neurokinin A

Neurokinin A is a member of the endogenous tachykinin agonist with preference for the NK-2R (NK-2 receptor) with greater potency as a bronchoconstrictor than Substance P. The comound has shown to be identical to substance K and neuromedin L1. Neurokinin A has been reported to effect reproduction by controlling at the hypothalamus level gonadotropin and prolactin secretion along with steroid secretion at the ovarian and gonadal level. An increase in inositol 1,4,5-trisphosphate (IP3) levels along with paralleled increase in intracellular free Ca²⁺ in BHK-21 cells with the NK-2R gene were stimulated with Neurokinin A. The compound has also been observed to induce contraction in muscle strips and single cells of the human sigmoid colon circular muscle. Neurokinin A has also been used to discover the location of tachykinin receptors.