Characterization and Amino Acid Composition of a Hypertrehalosaemic Neuropeptide from the Corpora cardiaca of the Cockroach, Nauphoeta cinerea

Institut für Zoologie IV der Universität Düsseldorf, Universitätsstraße 1, D-4000 Düsseldorf 1, Bundesrepublik Deutschland Z. Naturforsch. 42c, 225—230 (1987); received October 17, 1986 Corpora cardiaca, Hypertrehalosaemic Neuropeptide, Nauphoeta cinerea, Blood Carbohydrates, Fat Body Glycogen Phosphorylase Nauphoeta cinerea corpora cardiaca contain peptide material which is capable of eliciting strong hypertrehalosaemia (maximum increase: 27 mg carbohydrates/ml haemolymph) and fat body glycogen phosphorylase-activation (maximal: 70% of the total phosphorylase activity in the a-form) in the American cockroach, Periplaneta americana. It appears that comparable amounts of bioactive material are stored in the corpora cardiaca of N. cinerea and P. americana. Purifica­ tion of a methanolic extract of corpora cardiaca from N. cinerea by reversed-phase HPLC revealed that the hypertrehalosaemic phosphorylase-activating activity is concentrated in a single peak. The amino acid composition of the purified neuropeptide material was determined after acid hydrolysis with HC1 and methanesulfonic acid. The analyses demonstrated that the N. cinerea hypertrehalosaemic factor is a decapeptide which contains the following amino acid residues: Asp, Thr, Ser, Glu, Pro, Gly (2), Val, Phe, and Trp.