A CLONED NK2 RECEPTOR MEDIATES PHOSPHATIDYLINOSITOL HYDROLYSIS IN A TRANSFECTED MURINE FIBROBLAST

Transfection of a bovine stomach cDNA encoding for an NK2 receptor into murine fibroblasts produced a clone that exhibited specific binding of NKA, a selective NK2 agonist. In these transfected cells, NKA mediated hydrolysis of phosphatidyl-inositol (PI) with an EC50 value of 10 nM and an Emax value 7.2 times basal level. Dose response curves of IP1 accumulation by two other neurokinin agonists demonstrated a rank order of potency of NKA>SP>>senktide. This suggests that the de novo receptor expressed in these transfected cells is functionally coupled to the PI hydrolysis pathway. Stable in vitro expression of NK2 receptors in a eukaryotik cell line can provide a means of correlating the structurally defined receptor with its ligand binding properties and its functional coupling mechanisms. © 1990.