The action of substance P on contraction, inositol phospholipids and adenylate cyclase in rat small intestine.

The actions of substance P and eledoisin on contraction, [3H]inositol 1-phosphate and cAMP formation in the rat ileum have been compared. Eledoisin was considerably more potent than substance P on both contraction and [3H]inositol 1-phosphate production. Neither peptide altered the cAMP levels in the tissue. These results are discussed in relation to the substance P receptor sub-type present in the rat ileum, and its second messenger.