CALLITACHYKININ-I AND CALLITACHYKININ-III, 2 NOVEL MYOTROPIC PEPTIDESISOLATED FROM THE BLOWFLY, CALLIPHORA-VOMITORIA, THAT HAVE RESEMBLANCES TO TACHYKININS

Two peptides, related to the locust myotropic peptides locustatachykin in I-IV, were isolated from the blowfly Calliphora vomitoria. Whole, f rozen flies were used for extraction with acidified methanol. A cockro ach hindgut muscle contraction bioassay was used for monitoring fracti ons during subsequent purification steps. A series of eight different high performance liquid chromatography column systems was required to obtain optically pure peptides. Two peptides were isolated and their s equences determined by Edman degradation and confirmed by mass spectro metry and chemical synthesis as APTANGVR-NH2 and GLGNNANGVR-NH2. They were named callitachykinin I and II. The peptides have sequence simila rities to the locustatachykinins and vertebrate tachykinins. Both call itachykinins were recognized by an antiserum to locustatachykinin I in enzyme-linked immunosorbent assay (ELISA) tests and callitachykinin I I was additionally recognized by an antiserum to the Vertebrate tachyk inin kassinin, suggesting that immunolabeling of blowfly neurons with these antisera is due to neuronal callitachykinins.