Quantification of adipokinetic hormones I and II in the corpora cardiaca of Schistocerca gregaria and Locusta migratoria

1. 1. A method is described to quantify the amounts of adipokinetic hormones I and II (AKHI and AKHII) in the corpora cardiaca (CC) of Schistocerca gregaria and Locusta migratoria. These two hormones can be separated in a single reversed-phase high-performance liquid chromatography step with 0.1% trifluoroacetic acid and acetonitrile as the solvent system. The peaks were identified by their retention times with reference to synthetic and/or natural peptides. The peaks were detected at 206 nm, their area integrated and compared with a series of areas obtained for known amounts of synthetic AKHI chromatographed under the same conditions. 2. 2. The first quantification data for AKHI and AKHII are presented for 5th instar larvae and adult S. gregaria and L. migratoria 3. 3. At any given time during the period studied it was found that the CC always contained more AKHI than AKHII; the molar ratio AKHI: AKHII ranged from 2:1 to 6:1. 4. 4. S. gregaria contained more of the two peptides than L. migratoria. 5. 5. In most of the developmental stages studied more hormone was found in females than in males.