The isolation and identification of three diuretic kinins from the abdominal ventral nerve cord of adult Helicoverpa zea

Three novel diuretic peptides have been isolated and identified from the abdominal ventral nerve cord of the adult corn earworm, Helicoverpa zea. The peptides belong to the kinin family of myotropic and diuretic peptides and have the following sequences: YFSPWGamide, VRFSPWGamide, and KVKFSAWGamide. These peptides, which we refer to as the helicokinins, are potent stimulators of secretion by the Malpighian tubules of Manduca sexta. All three of the helicokinins stimulated secretion by M. sexta tubules at concentrations below 10 −11 M. The helicokinins are the first kinins to be identified from a lepidopteran, and the first diuretic peptides to be identified specifically from the abdominal ventral nerve cord of any insect.