ISOLATION AND PRIMARY STRUCTURE OF 2 PEPTIDES WITH CARDIOACCELERATORY AND HYPERGLYCEMIC ACTIVITY FROM THE CORPORA CARDIACA OF PERIPLANETA-AMERICANA

Two cardioacceleratory peptides from the corpora cardiaca of P. americana were purified by gel filtration and reversed-phase liquid chromatography. Analysis of the intact factors and their chymotryptic fragments, assigned the primary structure of these octapeptides as pGlu-Val-Asn-Phe-Ser-Pro-Asn-Trp-NH2, designated periplanetin CC-1 and pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-NH2, designated periplanetin CC-2. They represent new members of a family of invertebrate peptides that includes locust adipokinetic hormone and crustacean red-pigment concentrating hormone. Bothe peptides show adipokinetic activity in grasshoppers and hyperglycemic activity in cockroaches. One of these peptides (CC-2) has provocative sequence homology with the NH2-terminal portion of glucagon.