Comparative potencies of substance P, substance K and neuromedin K on brain substance P receptors.
The relative potency of substance P, substance K and neuromedin K on [3H]substance P binding has been compared in rat brain membrane preparations. Substance K and neuromedin K, two newly isolated substance P-related mammalian peptides, are very weak competitors for [3H]substance P binding sites. It suggests that these two neuropeptides are not acting on the same receptor type as substance P. Moreover, previous substance P receptor classifications are unlikely to be applicable to brain tachykinin receptor sub-types.
D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D008297:Male; D015288:Neurokinin A; D015287:Neurokinin B; D009842:Oligopeptides / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism*; D018040:Receptors, Neurokinin-1; D013373:Substance P / Q000378:metabolism*
D009842:Oligopeptides; D011956:Receptors, Cell Surface; D018040:Receptors, Neurokinin-1; D013373:Substance P; D015288:Neurokinin A; D015287:Neurokinin B